Related Articles

Summary

Background

A variety of apheresis devices are now available on the market for plateletapheresis. We compared two apheresis instruments (Fenwal Amicus and Fresenius COM.TEC) with regard to processing time, platelet (PLT) yield and efficiency, and white blood cell (WBC) content.

Material and Methods

Donors undergoing plateletpheresis were randomly separated into two groups (either the Amicus or the COM.TEC cell separator).

Results

In the pre-apheresis setting, 32 plateletpheresis procedures performed with each instrument revealed no significant differences in donors’ sex, age, weight, height and total blood volume between the two groups. However, the pre-apheresis PLT count was higher with the COM.TEC than with the Amicus (198 × 103/μl vs. 223 × 103/μl; p = 0.035). The blood volume processed to reach a target PLT yield of ≥3.3 × 1011 was higher in the COM.TEC compared to the Amicus (3,481 vs. 2,850 ml; p < 0.001). The median separation time was also significantly longer in the COM.TEC than in the Amicus (61 vs. 44 min; p < 0.001). 91 and 88% of the PLT products collected with the Amicus and the COM.TEC, respectively, had a PLT count of >3.3 × 1011 (p = 0.325). All products obtained with both instruments had WBC counts lower than 5 ↔ 106, as required. There was no statistical difference with regard to collection efficiency between the devices (55 ± 15 vs. 57 ± 15%; p = 0.477). However, the collection rate was significantly higher with the Amicus compared to the COM.TEC instrument (0.077 ± 0.012 × 1011 vs. 0.057 ± 0.008 × 1011 PLT/min; p < 0.001).

Conclusion

Both instruments collected platelets efficiently. Additionally, consistent leukoreduction was obtained with both instruments; however, compared with the COM.TEC instrument, the Amicus reached the PLT target yield more quickly.

Summary

Background

Soluble mediators in platelet concentrates (PCs) released from contaminating white blood cells (WBCs) and platelets (PLTs) themselves are supposed to promote allergic and non-hemolytic febrile transfusion reactions in the recipient. Pathogen reduction technologies (PRTs) prevent replication and proliferation of pathogens as well as of WBCs, and may reduce cytokine accumulation in PCs during storage and prevent adverse events after PLT transfusion. On the other hand, such treatments may also lead to increased cytokine production by stimulation of WBCs or PLTs due to the photochemical or photodynamical process itself.

Material and Methods

12 triple-dose PLT apheresis collections were leukoreduced by the process-controlled leukoreduction system of the Trima Accel machine and split into 3 units undergoing Mirasol-PRT treatment (M) or gamma irradiation (X) or remaining untreated (C). During storage for up to 7 days, PLT activation, WBC-derived Th-1/2, and inflammatory as well as PLT-derived cytokines were measured by cytometric bead array and enzymelinked immunosorbent assay, respectively.

Results

Independent of treatment, all PLT products exhibited low levels of WBC-associated cytokines near or below assay detection limits. WBC-associated cytokines were not elevated by Mirasol-PRT treatment. PLT-derived cytokines were detected at higher levels and increased significantly during storage in all units. Most likely due to higher PLT activation, M units showed significantly higher levels of PLT-derived cytokines compared to untreated and gamma-irradiated units on day 5 of storage.

Conclusion

In all PCs, PLTs themselves were the main source of cytokine release. Mirasol-PRT treatment was associated with a significantly increased PLT activation and accumulation of PLT-derived cytokines during storage, without affecting WBC-derived cytokines relative to controls.

During haemodialysis (HD), platelets (PLTs) are activated and release granule contents. As HD treatment occurs three times a week, it has been demonstrated that PLTs are exhausted due to the repetitive character of the treatment. To identify PLT depletion morphologically, PLT evaluation was performed by light microscopy and electron microscopy (EM) in a chronic HD subject and a healthy reference subject. Blood samples were taken before the start of HD treatment for measurement of PLT count, PLT volume and size parameters. Blood smears were screened by light microscopy for qualitative evaluation of PLT granule containing cytoplasm, as indicated by its staining density. Morphological PLT parameters of surface area and size of dense bodies were assessed by EM. Data were compared with results of a group of 20 chronic HD subjects and a group of 20 healthy reference subjects. With respect to the percentage of PLTs with appropriate staining density (>75%), light microscopic evaluation showed that this value (9%) was within the range of a group of chronic HD subjects, but considerably below the reference range (70%). EM evaluation revealed an average PLT surface area and dense bodies area of respectively 42% and 31%, if the healthy reference subject was set on 100%. PLTs from a chronic HD subject are considerably smaller and substantially less granular than PLTs from a healthy reference subject. These findings support the hypothesis of PLT depletion in chronic HD subjects due to frequent PLT activation and/or increased urea concentrations.

Summary

Background

We compare the actual with the potential donor exposure and possible infection rates in the Hanover Medical School (MHH) platelet (PLT) transfusion recipients if the current MHH standard of apheresis PLT concentrate (A-PC) supply would be replaced by a pooled PLT concentrate (P-PC) transfusion regimen.

Donors, Patients, and Methods

The electronic records of the MHH Institute of Transfusion Medicine and the MHH Department of Medical Controlling were evaluated to assess the development of PLT needs and supply at MHH from 2003–2006. For 2006, we evaluated all PLT transfusion recipients with respect to their overall transfusion needs, classified them for low and high PLT transfusion needs, and related them to the diagnostic groups that underlie their PLT demands. We assumed a P-PC preparation procedure using 4 whole blood-derived buffy coats for all calculations for potential donor exposure. To predict the possible infection rates of an unrecognized viral infection with low prevalence in the general population to A-PC or to P-PC recipients and the influence of neutralizing agent specific antibodies (NAB), we established a mathematical contamination/infection model based on the current PLT transfusion mode and data about GBV-C virus infection among Hanover blood donors.

Results

From 2003 to 2006, the 1,300–1,400 persons comprising MHH apheresis donor pool covered a 36% increase in PC transfusions. The exclusive use of P-PCs instead of A-PC would require a total of 36,240–49,276 whole blood donations to meet MHH demands, corresponding to a more than 1 log step increase in donor exposure. For individual hematological patients, the change to P-PCs would imply an 80–125%, for individual surgical patients a 40–50% higher donor exposure. Our infection model revealed an approximately 4 times higher infection.

Conclusions

A change to P-PC would imply a more than one log step higher donor exposure, and an unrecognized infection with a prevalence around 1% leads to an up to 4 times higher infection rate. A general change in the PC transfusion policy that favors P-PCs is dangerous and must be avoided.

Summary

Background

In vitro function of stored platelet (PLT) con-centrates was analyzed after applying two different techniques of pathogen reduction technology (PRT) treatment, which could increase cellular injury during processing and storage.

Methods

Nine triple-dose PLT apheresis donations were split into 27 single units designated to riboflavin-UVB (M) or psoralen-UVA (I) treatment or remained untreated (C). Throughout 8 days of storage, samples were analyzed for annexin V release, the mitochondrial transmembrane potential (Δψ) and some classical markers of PLT quality (pH, LDH release, hypotonic shock response (HSR)).

Results

PLT count and LDH release of all units maintained initial ranges. All units exhibited a decrease in pH and HSR and an increase in annexin V release and Δψ disruption. Notably, throughout the entire storage period, annexin V release re-mained lowest in M units. Throughout 7 days of storage, M units remained comparable to C units (p > 0.05), whereas inferior values were observed with I units. Here, differences to C units reached significance by day 1 (pH: p < 0.0001), day 5 (annexin V release: p < 0.014), and day 7 (HSR, Δψ: p ≤ 0.003). After PRT treatment, annexin V release and Δψ disruption were significantly (p < 0.001) correlated with pH and HSR.

Conclusion

During storage, all units showed a de-crease in HSR and an increase in acidity, annexin V release and Δψ disruption. While M units remained comparable to C units, I units demonstrated significantly inferior values during terminal storage. This could have resulted from differences in PRT treatment or simply be due to differences in storage media and should be analyzed for clinical relevance in future investigations.

Lymphocyte cultures grown from liver allograft biopsies were shown to exhibit alloreactivity towards donor cells as measured by primed lymphocyte testing (PLT). The PLT specificity was determined in assays using HLA typed panel cells and/or by inhibition testing with HLA specific monoclonal antibodies. Certain cultures exhibited PLT specificity towards class I HLA antigens of the donor, whereas others were specific for class II HLA antigens or recognized mixtures of class I and II antigens. These PLT specificity patterns were compared with clinical, histological and laboratory findings on the liver transplant patients at the time of the biopsy. Biopsies yielding class I specific PLT cells were taken generally during the earlier posttransplant period, whereas class II specific cells were grown from later biopsies. There was no significant correlation of the PLT specificity towards class I vs II antigens with the levels of total or direct bilirubin, serum glutamate oxaloacetic transaminase (SGOT), and serum glutamate pyruvate transaminase (SGPT), although a trend towards higher values was noted for biopsies presenting with a class II specific infiltrate. However, the levels of gamma glutamyl transpeptidase (GGTP) and alkaline phosphatase (AP) were significantly increased when biopsies yielded class II specific rather than class I specific PLT cells. Biopsy histology showed more damage to bile duct epithelium in association with class II PLT specificity whereas intense but often reversible infiltrates were found in biopsies yielding class I specific cells. The elevated GGTP and AP levels are probably related to the interaction of class II specific T cells with bile duct epithelium, which has been shown to express induced class II HLA antigens on their cell surface.

Background

Rapidly available and accurate platelet counts play an important role in the evaluation of haemorrhagic status and in assessing the need for platelet transfusions. We, therefore, evaluated platelet counting performance of haematology analysers using optical, impedance and immunological methods in thrombocytopenic patients.

Materials and Methods

We considered 99 patients with a platelet (plt) count under 50x109 plt/L. We compared the platelet counts obtained using ADVIA 2120 (optical method), Cell-Dyn Sapphire (optical, impedance and immunological methods with CD61) and a reference, double staining (CD41+CD61) immunological method.

Results

The platelet counts of all the considered methods showed good correlation with those of the reference method, despite an overestimation in platelet quantification. The degree of inaccuracy was greater for platelet counts under 20 x109 plt/L.

Conclusions

Clinicians who use platelet thresholds below 20 x109 plt/L for making clinical decisions must be aware of the limitations in precision and accuracy of cell counters at this level of platelet count. Inaccurate counts of low platelet numbers could create problems if attempts are made to reduce the threshold below 20x109 plt/L.

AIM: To establish a simple model consisting of the routine laboratory variables to predict both minimal fibrosis and cirrhosis in chronic hepatitis B virus (HBV)-infected patients.

METHODS: We retrospectively investigated 114 chronic HBV-infected patients who underwent liver biopsy in two different hospitals. Thirteen parameters were analyzed by step-wise regression analysis and correlation analysis. A new fibrosis index [globulin/platelet (GP) model] was developed, including globulin (GLOB) and platelet count (PLT). GP model = GLOB (g/mL) × 100/PLT (× 109/L). We evaluated the receiver operating characteristics analysis used to predict minimal fibrosis and compared six other available models.

RESULTS: Thirteen clinical biochemical and hematological variables [sex, age, PLT, alanine aminotransferase, aspartate aminotransferase (AST), albumin, GLOB, total bilirubin (T.bil), direct bilirubin (D.bil), glutamyltransferase, alkaline phosphatase, HBV DNA and prothrombin time (PT)] were analyzed according to three stages of liver fibrosis (F0-F1, F2-F3 and F4). Bivariate Spearman’s rank correlation analysis showed that six variables, including age, PLT, T.bil, D.bil, GLOB and PT, were correlated with the three fibrosis stages (FS). Correlation coefficients were 0.23, -0.412, 0.208, 0.220, 0.314 and 0.212; and P value was 0.014, < 0.001, 0.026, 0.018, 0.001 and 0.024, respectively. Univariate analysis revealed that only PLT and GLOB were significantly different in the three FS (PLT: F = 11.772, P < 0.001; GLOB: F = 6.612, P = 0.002). Step-wise multiple regression analysis showed that PLT and GLOB were also independently correlated with FS (R2 = 0.237). By Spearman’s rank correlation analysis, GP model was significantly correlated with the three FS (r = 0.466, P < 0.001). The median values in F0-F1, F2-F3 and F4 were 1.461, 1.720 and 2.634. Compared with the six available models (fibrosis index, AST-platelet ratio, FIB-4, fibrosis-cirrhosis index and age-AST model and age-PLT ratio), GP model showed a highest correlation coefficient. The sensitivity and positive predictive value at a cutoff value < 1.68 for predicting minimal fibrosis F0-F1 were 72.4% and 71.2%, respectively. The specificity and negative predictive value at a cutoff value < 2.53 for the prediction of cirrhosis were 84.5% and 96.7%. The area under the curve (AUC) of GP model for predicting minimal fibrosis and cirrhosis was 0.762 [95% confidence interval (CI): 0.676-0.848] and 0.781 (95% CI: 0.638-0.924). Although the differences were not statistically significant between GP model and the other models (P all > 0.05), the AUC of GP model was the largest among the seven models.

CONCLUSION: By establishing a simple model using available laboratory variables, chronic HBV-infected patients with minimal fibrosis and cirrhosis can be diagnosed accurately, and the clinical application of this model may reduce the need for liver biopsy in HBV-infected patients.

The metabolic and functional alterations which occur during the acute phase of nephrotoxic nephritis (NTN) in rats, a model of immune-mediated glomerulonephritis, result from a cooperative interaction between PMNs and platelets (PLTs). In consequence, we hypothesized that fibrinogen (Fg) might play a critical role in this process and, accordingly, we found that defibrination of animals decreased both the acute phase proteinuria in NTN (approximately 70%) as well as the influx of PLTs and PMNs into the glomerulus (approximately 40-50%). In contrast, blockade of the PLT Fg receptor, alpha IIb beta 3, with the RGD peptidomimetic SC-49992 decreased proteinuria (approximately 90%) without substantially altering the influx of PMNs or PLTs. Immunocytochemistry showed a marked increase in beta 3 integrin expression in inflamed glomeruli which was prevented either by PMN or PLT depletion before disease induction. FACS and immunocytochemical analysis of glomerular cell dissociates demonstrated that beta 3 integrin expression was predominantly on intraglomerular PLTs. In vitro, activated PLTs stimulated the PMN respiratory burst, an interaction which could be inhibited by Fg receptor blockade. In sum, acute NTN is accompanied by a marked increase in glomerular beta 3 integrin expression predominantly due to the influx of PLTs which localize to the glomerulus in a PMN-dependent fashion. Fg appears to serve a major role as a coactivating stimulus for PLT-PMNs in situ via alpha IIb beta 3, potentially mediating the PMN respiratory burst which contributes to proteinuria. Fg may also play a subsidiary role in PMN/PLT comigration.

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We previously reported that ultraviolet light B (UVB)-treated human platelets (hPLTs) can cause acute lung injury (ALI) in a two-event SCID mouse model in which the predisposing event was Lipopolysaccharide (LPS) injection and the second event was infusion of UVB-treated hPLTs. To delineate contributions of host mouse platelets (mPLTs) and neutrophils in the pathogenesis of ALI in this mouse model, we depleted mPLTs or neutrophils and measured hPLT accumulation in the lung. We also assessed lung injury by protein content in bronchoalveolar lavage fluid (BALF). LPS injection followed by infusion of UVB-treated hPLTs resulted in sequestration of both mPLTs and hPLTs in the lungs of SCID mice, although the numbers of neutrophils in the lung were not significantly different from the control group. Depletion of mouse neutrophils caused only a mild reduction in UVB-hPLTs accumulation in the lungs and a mild reduction in protein content in BALF. In comparison, depletion of mPLTs almost completely abolished hPLTs accumulation in the lung and significantly reduced protein content in BALF. UVB-treated hPLTs bound to host mPLTs, but did not bind to neutrophils in the lung. Aspirin treatment of hPLTs in vitro abolished hPLT accumulation in the lung and protected mice from lung injury. Our data indicate that host mPLTs accumulated in the lungs in response to an inflammatory challenge and subsequently mediated the attachment of transfused UVB-hPLTs. Neutrophils also recruited a small percentage of platelets to the lung. These findings may help develop therapeutic strategies for ALI which could potentially result from transfusion of UV illuminated platelets.

Platelets (PLTs) act in antimicrobial host defense by releasing PLT microbicidal proteins (PMPs) or PLT kinocidins (PKs). Receptors mediating staphylocidal efficacy and PMP or PK release versus isogenic PMP-susceptible (ISP479C) and -resistant (ISP479R) Staphylococcus aureus strains were examined in vitro. Isolated PLTs were incubated with ISP479C or ISP479R (PLT/S. aureus ratio range, 1:1 to 10,000:1) in the presence or absence of a panel of PLT inhibitors, including P2X and P2Y receptor antagonists of increasingly narrow specificity, and PLT adhesion receptors (CD41, CD42b, and CD62P). PLT-to-S. aureus exposure ratios of ≥10:1 yielded significant reductions in the viability of both strains. Results from reversed-phase high-performance liquid chromatography indicated that staphylocidal PLT releasates contained PMPs and PKs. At ratios below 10:1, the PLT antistaphylococcal efficacy relative to the intrinsic S. aureus PMP-susceptible or -resistant phenotype diminished. Apyrase (an agent of ADP degradation), suramin (a general P2 receptor antagonist), pyridoxal 5′-phosphonucleotide derivative (a specific P2X1 antagonist), and cangrelor (a specific P2Y12 antagonist) mitigated the PLT staphylocidal response against both strains, correlating with reduced levels of PMP and PK release. Specific inhibition occurred in the presence and absence of homologous plasma. The antagonism of the thromboxane A2, cyclooxygenase-1/cyclooxygenase-2, or phospholipase C pathway or the hindrance of surface adhesion receptors failed to impede PLT anti-S. aureus responses. These results suggest a multifactorial PLT anti-S. aureus response mechanism involving (i) a PLT-to-S. aureus ratio sufficient for activation; (ii) the ensuing degranulation of PMPs, PKs, ADP, and/or ATP; (iii) the activation of P2X1/P2Y12 receptors on adjacent PLTs; and (iv) the recursive amplification of PMP and PK release from these PLTs.

Mean platelet volume (MPV) and platelet count (PLT) are highly heritable and tightly regulated traits. We performed a genome-wide association study for MPV and identified one SNP, rs342293, as having highly significant and reproducible association with MPV (per-G allele effect 0.016 ± 0.001 log fL; P < 1.08 × 10−24) and PLT (per-G effect −4.55 ± 0.80 109/L; P < 7.19 × 10−8) in 8586 healthy subjects. Whole-genome expression analysis in the 1-MB region showed a significant association with platelet transcript levels for PIK3CG (n = 35; P = .047). The G allele at rs342293 was also associated with decreased binding of annexin V to platelets activated with collagen-related peptide (n = 84; P = .003). The region 7q22.3 identifies the first QTL influencing platelet volume, counts, and function in healthy subjects. Notably, the association signal maps to a chromosome region implicated in myeloid malignancies, indicating this site as an important regulatory site for hematopoiesis. The identification of loci regulating MPV by this and other studies will increase our insight in the processes of megakaryopoiesis and proplatelet formation, and it may aid the identification of genes that are somatically mutated in essential thrombocytosis.

This study investigated the relationship between platelet (PLT) serotonin (5-HT) and intestinal permeability in children with pervasive developmental disorders (PDD). Differential sugar absorption and PLT 5-HT were determined in 23 children with PDD. PLT 5-HT (2.0–7.1 nmol/109 PLT) was elevated in 4/23 patients. None exhibited elevated intestinal permeability (lactulose/mannitol ratio: 0.008–0.035 mol/mol). PLT 5-HT did not correlate with intestinal permeability or GI tract complaints. PLT 5-HT correlated with 24 h urinary 5-hydroxyindoleacetic acid (5-HIAA; p = .034). Also urinary 5-HIAA and urinary 5-HT were interrelated (p = .005). A link between hyperserotonemia and increased intestinal permeability remained unsupported. Increased PLT 5-HT in PDD is likely to derive from increased PLT exposure to 5-HT. Longitudinal studies, showing the (in)consistency of abnormal intestinal permeability and PLT 5-HT, may resolve present discrepancies in the literature.

BACKGROUND

Blood group A and B antigens are expressed only weakly on platelets (PLTs) of most individuals but are very strongly expressed on PLTs from approximately 1 percent of normal subjects (Type II high expressers). The implications of this trait for transfusion medicine are undefined.

STUDY DESIGN AND METHODS

A family was studied in which two Group B infants were born with neonatal thrombocytopenia, whereas a third infant whose blood group was A2 had a normal PLT count at birth.

RESULTS

Serologic studies demonstrated a maternal antibody that reacted strongly with PLTs from the father and the two group B children in flow cytometry and with GPIIb/IIIa from their PLTs in solid-phase assays. No PLT-specific antibodies were detected in maternal serum sample, but it contained a high-titer immunoglobulin G antibody specific for blood group B. All PLT-reactive antibody in the mother’s serum was removed by absorption with pooled, washed group A and B red cells (RBCs). Studies with monoclonal anti-B and measurement of serum B-glycosyltransferase activity showed that the father and both group B children were Type II high expressers of blood group B.

CONCLUSIONS

The findings indicate that high-titer blood group antibodies acquired from the mother can cause thrombocytopenia in infants possessing the Type II high-expresser phenotype despite competition for antibody binding by blood group antigens expressed on RBCs and other tissues.

TLR9 localizes to a novel intracellular compartment called the T granule to promote immune signaling by platelets.

Human and murine platelets (PLTs) variably express toll-like receptors (TLRs), which link the innate and adaptive immune responses during infectious inflammation and atherosclerotic vascular disease. In this paper, we show that the TLR9 transcript is specifically up-regulated during pro-PLT production and is distributed to a novel electron-dense tubular system-related compartment we have named the T granule. TLR9 colocalizes with protein disulfide isomerase and is associated with either VAMP 7 or VAMP 8, which regulates its distribution in PLTs on contact activation (spreading). Preincubation of PLTs with type IV collagen specifically increased TLR9 and CD62P surface expression and augmented oligodeoxynucleotide (ODN) sequestration and PLT clumping upon addition of bacterial/viral ODNs. Collectively, this paper (a) tracks TLR9 to a new intracellular compartment in PLTs and (b) describes a novel mechanism of TLR9 organization and signaling in human PLTs.

Introduction:

Platelet concentrate (PC) remains one of the most important support measures in thrombocytopenic patients. An efficient cell separator is a prerequisite for an optimally functioning apheresis setup. Donor blood count may undergo a temporary reduction after the procedure.

Aim:

The aim was to find the extent of reduction in donor blood count (hemoglobin, hematocrit, white blood cell, and platelet) after plateletpheresis and to evaluate the cell separator for collection efficiency, processing time, and leukoreduction.

Study Design and Methods:

Two hundred and thirty seven procedures performed on the Amicus (N = 121), Fenwal CS-3000 Plus (N = 50) and Cobe spectra (N = 66) in a one year period were evaluated. The procedures performed on the continuous flow centrifugation (CFC) cell separators and donor blood counts (pre and post donation) done were included in the study.

Results:

The percent reduction in hemoglobin (HB), hematocrit (HCT), white blood cell (WBC) and platelet count ((PLT ct) was 2.9, 3.1, 9, 30.7 (Mean, N = 237) respectively after the procedure. The post donation PLT ct reduced to < 100×109/L (range 80-100) in five donors (N = 5/237, Amicus). The pre donation PLT ct in them was 150-200×109/L. Collection efficiency (percent) of Amicus (79.3) was better as compared to the other two machines (CS: 62.5, Cobe: 57.5). PC collected on Cobe spectra had <1×106 WBC. The donor pre donation PLT levels had a positive correlation to the product PLT yield (r = 0.30, P = 0.000).

Conclusion:

Monitoring donor blood counts helps to avoid pheresis induced adverse events. A cautious approach is necessary in donors whose pre donation PLT ct is 150-200×109/L. The main variable in PLT yield is donor PLT ct (pre donation). High collection efficiency is a direct measure of an optimally functioning cell separator.

BACKGROUND

The combination of granulocyte–colony-stimulating factor (G-CSF) and dexamethasone is an effective granulocyte mobilization regimen. The short-term side effects of G-CSF are well studied, but the potential long-term effects of repeated G-CSF stimulation in unrelated volunteer granulocyte donors have not been reported.

STUDY DESIGN AND METHODS

Donors who had received G-CSF three or more times for granulocytapheresis between 1994 and 2002 were identified and attempts were made to contact them if they were no longer active donors. They were matched with control platelet (PLT) donors for sex, age, and approximate number of cytapheresis donations. A health history was obtained and complete blood counts (CBCs) and C-reactive protein (CRP) determined where feasible.

RESULTS

Ninety-two granulocyte donors were identified, and 83 of them were contacted. They contributed to 1120 granulocyte concentrates, or a mean of 13.5 granulocytapheresis procedures per donor (and a mean of 87.5 plateletpheresis procedures per donor). There was no difference in CBCs between the granulocyte donors and the control PLT donors. There was no difference in CRP between the two groups, and no difference in pre- and post–G-CSF CRP in a subset of 22 granulocyte donors. Predefined health events included malignancies, coronary artery disease, and thrombosis. At a median 10-year follow-up, there were seven such events in the granulocyte donors and five in the PLT donors.

CONCLUSION

Although the number of granulocyte donors studied is small and continued surveillance of healthy individuals after G-CSF is prudent, our data suggest that G-CSF/dexamethasone stimulation appears to be safe.

Background

There are limited data on the evolution of the leukocyte and platelet counts in malaria patients.

Methods

In a clinical trial of chloroquine vs. chloroquine plus doxycycline vs. doxycycline alone against Plasmodium vivax (n = 64) or Plasmodium falciparum (n = 98) malaria, the total white cell (WCC) and platelet (PLT) counts were measured on Days 0, 3, 7 and 28 in 57 indigenous Papuans with life long malaria exposure and 105 non Papuan immigrants from other parts of Indonesia with limited malaria exposure.

Results

The mean Day 0 WCC (n = 152) was 6.492 (range 2.1–13.4) × 109/L and was significantly lower in the Papuans compared to the non Papuans: 5.77 × 109/L vs. 6.86 × 109/L, difference = -1.09 [(95% CI -0.42 to -1.79 × 109/L), P = 0.0018]. 14 (9.2%) and 9 (5.9%) patients had leukopaenia (<4.0 × 109/L) and leukocytosis (>10.0 × 109/L), respectively. By Day 28, the mean WCC increased significantly (P = 0.0003) from 6.37 to 7.47 × 109/L (73 paired values) and was similar between the two groups. Ethnicity was the only WCC explanatory factor and only on Day 0.

The mean Day 0 platelet count (n = 151) was 113.0 (range 8.0–313.0) × 109/L and rose significantly to 186.308 × 109/L by Day 28 (P < 0.0001). There was a corresponding fall in patient proportions with thrombocytopaenia (<150 × 109/L): 119/151 (78.81%) vs. 16/73 (21.92%, P < 0.00001). Papuan and non Papuan mean platelet counts were similar at all time points. Only malaria species on Day 0 was a significant platelet count explanatory factor. The mean D0 platelet counts were significantly lower (P = 0.025) in vivax (102.022 × 109/L) vs. falciparum (122.125 × 109/L) patients.

Conclusion

Changes in leukocytes and platelets were consistent with other malaria studies. The Papuan non Papuan difference in the mean Day 0 WCC was small but might be related to the difference in malaria exposure.

Background

There are multiple benefits to transfusing only ABO identical blood components. Historically our institution routinely transfused ABO non-identical platelets (PLTs) and cryoprecipitate to surgical patients. In April 2005, we implemented a policy of transfusing only ABO identical components whenever feasible, regardless of outdating/logistic considerations.

Methods

Technical staff closely monitored product usage and adjusted blood center orders based on recent utilization and planned transfusions. When unable to provide ABO identical PLTs ABO compatible platelets were washed to remove incompatible plasma. Data on outdating were collected for eighteen months before and after implementation. We compared transfusion reaction and red cell alloimmunization incidence for four years preceding (2001–2004) and subsequent (2006–2009) to implementation.

Results

In the year following implementation, only 11 of 410 surgical patients received ABO non-identical platelets (2.7%). There was a 5.6% increase in outdating of platelets. Transfusing ABO identical components was associated with significant reductions in febrile (−46%; 8.0 to 4.3 per 10,000 components; p<0.0001) and allergic transfusion reactions (−23%; from 7.0 to 5.4 per 10,000 components; p=0.025). A progressive reduction in de novo red cell alloimmunization incidence also occurred (−50% by 2009; p=0.03).

Conclusions

Providing ABO identical platelets to almost all patients was feasible in our setting by changing ordering and inventorying procedures, and making the ABO identical policy a staff priority. Unexpected and striking reductions in febrile and allergic reactions, and red cell alloimmunization were observed, of uncertain causal relationship to this ABO policy change, which will require further study.

Background

We aimed to investigate the relation of platelet count (PLT) and plateletcrit (PCT), mean platelet volume (MPV) and platelet distribution width (PDW) with other acute phase reactants and radiological extent in pulmonary tuberculosis (PTB).

Methods

One hundred patients with PTB (Group 1), 50 patients with community-acquired pneumonia (Group 2) and 28 healthy control individuals (Group 3) were included in this analytic study.

Results

WBC (White Blood Cell), ESR (Eritrocyte Sedimentation Rate), CRP (C-Reactive Protein), PLT and PCT values were both in Group 1 and Group 2 than in Group 3. PDW values were significantly higher in Group 1 than Group 3. WBC, ESR and CRP values were lower, while PLT and PCT values were higher in the Group 1 compared to Group 2 (p < 0.001). PLT was positively correlated with CRP and ESR values in the tuberculosis group (p < 0.001), while it was not correlated with CRP and ESR in the pneumonia group (p > 0.05). ESR, CRP, PLT and PCT values were found higher in radiological advanced stage (Stage 3) patients with PTB, while hemoglobin (Hb) was found lower (p < 0.05). Higher WBC, ESR, CRP and PCT values as well as radiological advanced stage were more common in PTB patients with thrombocytosis compared to the patients with normal platelet count, whereas Hb was found lower in these patients.

Conclusions

This study indicates that reactive thrombocytosis and higher PCT and PDW develop frequently in PTB and there is a relation between thrombocytosis and acute phase reactants, that is the inflammatory response. In addition, tuberculosis with radiological advanced stage is seen more frequently in the patients with thrombocytosis and higher PCT, drawing attention to the possible role of platelets in the cell-based immune process of tuberculosis.

AIM: To evaluate survival and recurrence after salvage liver transplantation (SLT) for the treatment of hepatocellular carcinoma (HCC) compared with primary liver transplantation (PLT) using a meta-analysis.

METHODS: Literature on SLT versus PLT for the treatment of HCC published between 1966 and July 2011 was retrieved. A meta-analysis was conducted to estimate pooled survival and disease-free rates. A fixed or random-effect model was established to collect the data.

RESULTS: The differences in overall survival and disease-free survival rates at 1-year, 3-year and 5-year survival rates were not statistically significant between SLT group and PLT group (P > 0.05). After stratifying the various studies by donor source and Milan criteria, we found that: (1) Living donor liver transplantation recipients had significantly higher 1-year survival rate, lower 3-year and 5-year survival rates compared with deceased-donor liver transplantation (DDLT) recipients. And in DDLT recipients they had better 1-year and 5-year disease-free survival rate in SLT group; and (2) No difference was seen in 1-year, 3-year and 5-year survival rates between two groups who beyond Milan criteria at the time of liver transplantation.

CONCLUSION: SLT can be effectively performed for patients with recurrence or deterioration of liver function after hepatectomy for HCC. It does not increase the perioperative mortality and has a similar long-term survival rates compared to PLT.

BACKGROUND

The combination of granulocyte–colony-stimulating factor (G-CSF [filgrastim]) and dexamethasone (G-CSF/dex) is an effective granulocyte mobilization regimen, but the variables that affect donor neutrophil response and granulocyte collection yield are not well characterized.

STUDY DESIGN AND METHODS

A computerized database containing records of 1198 granulocyte collections from 137 unrelated volunteer apheresis donors during a 13-year period was retrospectively analyzed. Donors were categorized by age, sex, and cumulative number of granulocyte donations. Complete blood counts at baseline and after G-CSF/dex stimulation were recorded. The outcome variables include the pre-procedure absolute neutrophil count (preANC), which reflects G-CSF/dex stimulation, and the granulocyte product yield per liter processed (BagGranYield/L).

RESULTS

Higher baseline ANC and platelet (PLT) counts were significantly associated with higher preANC while a larger number of prior granulocytapheresis procedures was associated with lower preANC. Total filgrastim dose (used in weight-based dosing) did not significantly impact preANC or the granulocyte yield; weight-based dosing at 5 μg per kg and a uniform 480-μg dose produced equivalent preANC. PreANC and weight were the key determinants of granulocyte yield (BagGranYield/L).

CONCLUSION

Apheresis donors with higher baseline PLT counts and ANCs have higher ANCs after G-CSF/dex stimulation; donor age, weight, and sex do not have a significant impact. A uniform G-CSF dose of 480 μg is as effective as weight-based dosing at 5 μg per kg. Donor ANC monitoring should be considered after serial granulocytapheresis procedures.

The paucity of lymph node T cells (plt) mutation leads to a loss of CCL21 and CCL19 expression in secondary lymphoid organs. plt mice have defects in the migration of naive T cells and activated dendritic cells into the T cell zones of lymphoid organs, suggesting that they would have defects in T cell immune responses. We now demonstrate T cell responses in plt mice are delayed but ultimately enhanced. Responses to contact sensitization are decreased at day 2 after priming but increased at day 6. After subcutaneous immunization, antigen-specific T cell proliferation and cytokine production in plt mice are increased and remain markedly elevated for at least 8 wk. Compared with wild-type mice, a proportion of T cell response in plt mice are shifted to the spleen, and prior splenectomy reduces the T cell response in draining lymph nodes. After immunization of plt mice, T cells and dendritic cells colocalize in the superficial cortex of lymph nodes and in splenic bridging channels, but not in T cell zones. These results demonstrate that plt mice mount robust T cell responses despite the failure of naive T cells and activated dendritic cells to enter the thymus dependent areas of secondary lymphoid organs.

Central memory CD8+ T cells (TCM) confer superior protective immunity against infections compared with other T cell subsets. TCM recirculate mainly through secondary lymphoid organs, including peripheral lymph nodes (PLNs). Here, we report that TCM, unlike naive T cells, can home to PLNs in both a CCR7-dependent and -independent manner. Homing experiments in paucity of lymph node T cells (plt/plt) mice, which do not express CCR7 ligands in secondary lymphoid organs, revealed that TCM migrate to PLNs at ∼20% of wild-type (WT) levels, whereas homing of naive T cells was reduced by 95%. Accordingly, a large fraction of endogenous CD8+ T cells in plt/plt PLNs displayed a TCM phenotype. Intravital microscopy of plt/plt subiliac lymph nodes showed that TCM rolled and firmly adhered (sticking) in high endothelial venules (HEVs), whereas naive T cells were incapable of sticking. Sticking of TCM in plt/plt HEVs was pertussis toxin sensitive and was blocked by anti-CXCL12 (SDF-1α). Anti-CXCL12 also reduced homing of TCM to PLNs in WT animals by 20%, indicating a nonredundant role for this chemokine in the presence of physiologic CCR7 agonists. Together, these data distinguish naive T cells from TCM, whereby only the latter display greater migratory flexibility by virtue of their increased responsiveness to both CCR7 ligands and CXCL12 during homing to PLN.

BACKGROUND

Hemolytic transfusion reactions (HTRs) can occur with transfusion of platelets (PLTs) containing ABO-incompatible plasma. Reported cases have involved group O donors. Two cases of PLT-mediated HTRs associated with the same group A plateletpheresis component, collected from a donor taking high doses of probiotics are reported.

CASE REPORT

Case 1 was a 40-year-old 69-kg group B stem cell transplant patient who received one-half of a group A plateletpheresis component. Severe back pain occurred 10 minutes into the transfusion, accompanied by anemia and hyperbilirubinemia. Case 2 was a 5-year-old 26-kg group B male with aplastic anemia who received the other half of the same plateletpheresis component, volume reduced to 37 mL. Syncope occurred immediately after the transfusion, with laboratory evidence of hemolysis a few hours later.

RESULTS

Serologic investigation of posttransfusion samples from both patients revealed positive direct anti-globulin tests: C3d only for Case 1 and immunoglobulin (Ig)G and C3d for Case 2; the eluates contained anti-B. The group A donor’s anti-B titer was 16,384 at saline and IgG phases. Donor lookback revealed that the donor had donated 134 apheresis PLTs over many years. For 3 years, he had intermittently taken probiotics; 3 weeks before the index donation, he began taking three tablets of probiotics every day. Lookback of prior group B recipients uncovered a case of acute hemolysis that was not recognized at the time. The solubilized probiotic inhibited anti-B in vitro.

CONCLUSION

Non–group O PLT donors can have high-titer anti-A or anti-B that might mediate HTRs, and probiotic ingestion in blood donors represents a novel mechanism of stimulating high-titer anti-B.