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1.  Degree of modification of Ro60 by the lipid peroxidation by-product 4-hydroxy-2-nonenal may differentially induce Sjögren's syndrome or systemic lupus erythematosus in BALB/c mice 
Free radical biology & medicine  2010;50(10):1222-1233.
Our previous work showed that immunization of rabbits with 4-hydroxy 2-nonenal-modified Ro60 (HNE-Ro60) accelerates autoimmunity. We extended this model into mice, hypothesizing that the severity of autoimmunity would be dependent on degree of HNE-modification of Ro60. Five groups of BALB/c mice (ten/group) were used. Group I was immunized with Ro60. Groups II to IV were immunized with Ro60 modified with 0.4 mM (low), 2 mM (medium) and 10 mM (high) HNE respectively. Group V controls received Freund's adjuvant. A rapid abrogation of tolerance to Ro60/La antigens occurred in mice immunized with HNE-modified Ro60, especially in the low and medium HNE-Ro60 groups. Lymphocytic infiltration and significantly high decrement in salivary flow (37%) compared to controls was observed only in high HNE-Ro60 group, suggesting induction of a SS-like condition in this group. Anti-dsDNA occurred only in mice immunized with medium HNE-Ro60. This group did not have significant decrement in salivary flow, suggesting induction of SLE-like manifestation in this group. Significantly high antibodies to Ro60 were found in saliva of mice in low and medium HNE-Ro60, and Ro60 groups as well as anti-HNE Ro60 in low and medium HNE-Ro60 groups. Understanding the mechanism of this differential induction may help delineate between these two autoimmune diseases.
PMCID: PMC3591494  PMID: 20946951
Sjögren's syndrome; SLE; autoimmunity; epitope spreading; autoantibodies; antigens; 4-hydroxy-2-nonenal; oxidative damage
2.  Heat-solubilized curry spice curcumin inhibits antibody-antigen interaction in in vitro studies: A possible therapy to alleviate autoimmune disorders 
Molecular nutrition & food research  2010;54(8):1202-1209.
Chronic and complex autoimmune diseases, currently treated palliatively with immunosuppressives, require multi-targeted therapy for greater effectiveness. The naturally occurring polyphenol curcumin has emerged as a powerful “nutraceutical” that interacts with multiple targets to regress diseases safely and inexpensively. Upto 8 g/day of curcumin for 18 months was non-toxic to humans. However, curcumin's utility is limited by its aqueous insolubility. We have demonstrated a heat-mediated 12-fold increase in curcumin's aqueous solubility. Here we show by, SDS-PAGE and SPR, that heat-solubilized curcumin binds to proteins. Based on this binding we hypothesized that heat-solubilized curcumin or turmeric would prevent autoantibody targeting of cognate autoantigens. Heat-solubilized curcumin/turmeric significantly decreased binding of autoantibodies from Sjögren's syndrome (SS) (up to 43/70 % respectively) and SLE (up to 52/70 % respectively) patients as well as an animal model of SS (up to 50/60 % respectively) to their cognate antigens. However, inhibition was not specific to autoimmunity. Heat-solubilized curcumin/turmeric also inhibited binding of polyclonal anti-spectrin to spectrin (50/56 % respectively). Thus, we suggest that the multifaceted heat-solubilized curcumin can ameliorate autoimmune disorders. In addition, the non-toxic curcumin could serve as a new protein stain in SDS-PAGE even though it is less sensitive than the Coomassie system which involves toxic chemicals.
PMCID: PMC3545698  PMID: 20146265
Curry spice; curcumin; turmeric; Curcuma longa; nutraceutical; autoimmunity; antioxidant; solubility; SDS-PAGE; protein staining
3.  Male only Systemic Lupus 
The Journal of rheumatology  2010;37(7):1480-1487.
Systemic lupus erythematosus (SLE) is more common among women than men with a ratio of about 10 to 1. We undertook this study to describe familial male SLE within a large cohort of familial SLE. SLE families (two or more patients) were obtained from the Lupus Multiplex Registry and Repository. Genomic DNA and blood samples were obtained using standard methods. Autoantibodies were determined by multiple methods. Medical records were abstracted for SLE clinical data. Fluorescent in situ hybridization (FISH) was performed with X and Y centromere specific probes, and a probe specific for the toll-like receptor 7 gene on the X chromosome. Among 523 SLE families, we found five families in which all the SLE patients were male. FISH found no yaa gene equivalent in these families. SLE-unaffected primary female relatives from the five families with only-male SLE patients had a statistically increased rate of positive ANA compared to SLE-unaffected female relatives in other families. White men with SLE were 5 times more likely to have an offspring with SLE than were White women with SLE but there was no difference in this likelihood among Black men. These data suggest genetic susceptibility factors that act only in men.
PMCID: PMC2978923  PMID: 20472921
Systemic lupus erythematosus; men; autoantibodies; genetics
4.  Location of Immunization and Interferon-γ Are Central to Induction of Salivary Gland Dysfunction in Ro60 Peptide Immunized Model of Sjögren's Syndrome 
PLoS ONE  2011;6(3):e18003.
Anti-Ro antibodies can be found in the serum of the majority of patients with Sjögren's syndrome (SS). Immunization with a 60-kDa Ro peptide has been shown to induce SS-like symptoms in mice. The aim of this study was to investigate factors involved in salivary gland (SG) dysfunction after immunization and to test whether the induction of SS could be improved.
Ro60 peptide immunization was tested in Balb/c mice, multiple antigenic peptide (MAP)-Ro60 and Pertussis toxin (PTX) were tested in SJL/J mice. In addition, two injection sites were compared in these two strains: the abdominal area and the tailbase. Each group of mice was tested for a loss of SG function, SG lymphocytic infiltration, anti-Ro and anti-La antibody formation, and cytokine production in cultured cells or homogenized SG extracts.
Ro60 peptide immunization in the abdominal area of female Balb/c mice led to impaired SG function, which corresponded with increased Th1 cytokines (IFN-γ and IL-12) systemically and locally in the SG. Moreover, changing the immunization conditions to MAP-Ro60 in the abdominal area, and to lesser extend in the tailbase, also led to impaired SG function in SJL/J mice. As was seen in the Balb/c mice, increased IFN-γ in the SG draining lymph nodes accompanied the SG dysfunction. However, no correlation was observed with anti-MAP-Ro60 antibody titers, and there was no additional effect on disease onset or severity.
Effective induction of salivary gland dysfunction after Ro60 peptide immunization depended on the site of injection. Disease induction was not affected by changing the immunization conditions. However, of interest is that the mechanism of action of Ro60 peptide immunization appears to involve an increase in Th1 cytokines, resulting in the induction of SG dysfunction.
PMCID: PMC3065457  PMID: 21464925
5.  SLE and C1q: A quantitative ELISA for determining C1q levels in serum 
Biotechnology journal  2009;4(8):1210-1214.
C1q is of interest in SLE research due to deficiencies in its activity being associated with the disease. Current published protocols for measuring C1q vary greatly in their results and ease of reproducibility. Due to this, average C1q concentrations have been reported between 56 and 276 µg/ml in non-SLE serum. We present an improved method for quantifying C1q concentrations that employs a sandwich ELISA. This method has improved precision, cost efficiency, up-scaling, reproducibility, and uses significantly lesser volumes of serum sample when compared to RID and other methods for quantifying C1q. We report an average concentration of 113±40 µg/ml for C1q in non-SLE serum. The assay designed here will be useful in the high-throughput measurement of serum C1q in SLE cases.
PMCID: PMC2829988  PMID: 19370710
C1q; ELISA; Serum; Systemic lupus erythematosus
6.  46,X,del(X)(q13) Turner's Syndrome Female with Systemic Lupus Erythematosus in a Pedigree Multiplex for SLE 
Genes and immunity  2009;10(5):478-481.
Systemic lupus erythematosus (SLE) disproportionately affects females. Recent work demonstrates that men with Klinefelter's syndrome (47,XXY males) have a similar risk of developing SLE as do genotypic females. We present an unusual case of an African American family with two SLE affected individuals in which one of the SLE patients also has Turner's syndrome [46,X,del(X)(q13)]. While not definitive, this family raises interesting questions regarding the role of genes located on the X chromosome in the development of SLE. The paucity of case reports documenting the overlap of SLE with Turner's syndrome while there is and association of male SLE with Klinefelter's syndrome suggests a lower risk of SLE in Turner's females. These observations are consistent with a gene dose effect at X with two X chromosomes (46,XX or 47,XXY) conferring higher risk and one X chromosome (46,XY or 45,XO) conferring lower risk of SLE.
PMCID: PMC2722751  PMID: 19458623
7.  Detection of Catalase as a major protein target of the lipid peroxidation product 4-HNE and the lack of its genetic association as a risk factor in SLE 
BMC Medical Genetics  2008;9:62.
Systemic lupus erythematosus (SLE) is a multifactorial disorder characterized by the presence of autoantibodies. We and others have implicated free radical mediated peroxidative damage in the pathogenesis of SLE. Since harmful free radical products are formed during this oxidative process, including 4-hydroxy 2-nonenol (4-HNE) and malondialdehyde (MDA), we hypothesized that specific HNE-protein adducts would be present in SLE red blood cell (RBC) membranes. Catalase is located on chromosome 11p13 where linkage analysis has revealed a marker in the same region of the genome among families with thrombocytopenia, a clinical manifestation associated with severe lupus in SLE affected pedigrees. Moreover, SLE afflicts African-Americans three times more frequently than their European-American counterparts. Hence we investigated the effects of a genetic polymorphism of catalase on risk and severity of SLE in 48 pedigrees with African American ancestry.
Tryptic digestion followed by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) analysis was used to identify the protein modified by HNE, following Coomassie staining to visualize the bands on the acrylamide gels. Genotyping analysis for the C → T, -262 bp polymorphism in the promoter region of catalase was performed by PCR-RFLP and direct PCR-sequencing. We used a "pedigree disequilibrium test" for the family based association analysis, implemented in the PDT program to analyze the genotyping results.
We found two proteins to be HNE-modified, migrating around 80 and 50 kD respectively. Tryptic digestion followed by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) analysis of the Coomassie stained 80 kD band revealed that the target of HNE modification was catalase, a protein shown to associate with RBC membrane proteins. All the test statistics carried out on the genotyping analysis for the C → T, -262 bp polymorphism in the promoter region of catalase were non-significant (p > 0.05) in our data, which suggested that this SNP is not associated with SLE.
Our results indicate that catalase is one of the proteins modified due to oxidative stress. However, catalase may not be a susceptibility gene for SLE. Nonetheless, catalase is oxidatively modified among SLE patients. This suggests a possible role between oxidative modification of catalase and its affects on enzymatic activity in SLE. An oxidatively modified catalase could be one of the reasons for lower enzymatic activity among SLE subjects, which in turn could favor the accumulation of deleterious hydrogen peroxide. Furthermore, HNE-products are potential neoantigens and could be involved in the pathogenesis of SLE. Decrease in catalase activity could affect the oxidant-antioxidant balance. Chronic disturbance of this balance in patients with SLE may work favorably for the premature onset of atherogenesis with severe vascular effect.
PMCID: PMC2474584  PMID: 18606005
8.  Improved detection of small deletions in complex pools of DNA 
Nucleic Acids Research  2002;30(12):e52.
About 40% of the genes in the nematode Caenorhabditis elegans have homologs in humans. Based on the history of this model system, it is clear that the application of genetic methods to the study of this set of genes would provide important clues to their function in humans. To facilitate such genetic studies, we are engaged in a project to derive deletion alleles in every gene in this set. Our standard methods make use of nested PCR to hunt for animals in mutagenized populations that carry deletions at a given locus. The deletion bearing animals exist initially in mixed populations where the majority of the animals are wild type at the target. Therefore, the production of the PCR fragment representing the deletion allele competes with the production of the wild type fragment. The size of the deletion fragment relative to wild type determines whether it can compete to a level where it can be detected above the background. Using our standard conditions, we have found that when the deletion is <600 bp, the deletion fragment does not compete effectively with the production of the wild type fragment in PCR. Therefore, although our standard methods work well to detect mutants with deletions >600 bp, they do not work well to detect mutants with smaller deletions. Here we report a new strategy to detect small deletion alleles in complex DNA pools. Our new strategy is a modification of our standard PCR based screens. In the first round of the nested PCR, we include a third PCR primer between the two external primers. The presence of this third primer leads to the production of three fragments from wild type DNA. We configure the system so that two of these three fragments cannot serve as a template in the second round of the nested PCR. The addition of this third primer, therefore, handicaps the amplification from wild type template. On the other hand, the amplification of mutant fragments where the binding site for the third primer is deleted is unabated. Overall, we see at least a 500-fold increase in the sensitivity for small deletion fragments using our new method. Using this new method, we report the recovery of new deletion alleles within 12 C.elegans genes.
PMCID: PMC117294  PMID: 12060690

Results 1-8 (8)