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1.  Suppressor T cells and host resistance to tye 111 pneumococcus after treatment with antilymphocyte serum. 
Infection and Immunity  1975;12(6):1307-1312.
The antibody response to type III pneumococcal polysaccharide (SS-II) was significantly increased in mice treated with antilymphocyte serum (ALS). BALG/c mice given 0.25 ml of ALS on days -1, 0, and 1 relative to the days of immunization with 0.5 mug of SSS-II had a 20-fold increment (11,383 increased to 199,917) in the number of splenic plaque-forming cells enumerated on day 5 compared with untreated, immunized controls. This effect has been attributed to the elimination of subpopulation of thymus-derived lymphocytes (T cells) that has suppressor function. The present series of experiments relate the augmented antibody response to SSS-II in mice treated with ALS to increased host resistance after infection with Streptococcus pneumoniae, type III (Pn-II). The 50% lethal dose of Pn-III in niminnunized mice was 102 and the 100% lethal dose was 103 organisms. Mice immunized with 0.5 mug of SSS-III and challenged 5 days later with Pn-III were completely protected against a dose of up to 108 organisms. Mice treated with 0.25 ml of ALS on days -1, 0, and 1, immunized with SSS-III on day 0, and challenged with 2.5 X 10(9) Pn-III on day 5 had a mean survival time of greater than 100 h compared with 16 h for immunized non-serum-treated controls. Animals given a single injection of ALS before immunization showed no increase in resistance, whereas mice treated after immunization had significant prolongation of survival times. Untreated, immunized mice challenged with 5 X 10(9), 1 X 5 X 10(8) Pn-II survived 14 to 19 h, whereas ALS-treated animals had mean survival times of 48, 174, and 222 h, respectively. These findings suggest that immunoregulatory T cells may have a biologically significant effect in a narrow zone in which the normal host immune response is insufficient but still potentially capable of providing some additional degree of protection if suppressor cells are elimated.
PMCID: PMC415436  PMID: 1345
2.  Changes in blood pH in rats after infection with Streptococcus pneumoniae. 
Infection and Immunity  1975;11(4):724-726.
Acid-base alterations in Streptococcus pneumoniae infection were studied in 80 male albino rats. Hematocrit and concentrations of plasma electrolytes, glucose, and total protein were also measured. At 3-h intervals throughout a 27-h study, four control and four infected rats were anesthetized with ether, and blood samples were taken. Arterial blood pH, Po2, and hematocrit increased in the infected group, whereas arterial Pco2, HCO3-, and venous Po2 decreased. Plasma K+ concentration increased slightly and glucose levels decreased in the infected rats as the sepsis progressed. No significant changes were observed in venous blood pH, HCO3-, and Pco2. Plasma Na+, Cl-, and total protein remained unchanged. The increase in arterial blood pH and decrease in arterial Pco2 and HCO3- indicated respiratory alkalosis, which was present in rats infected with S. pneumoniae.
PMCID: PMC415127  PMID: 235492
3.  Factors Affecting the Production of Candicidin 
Factors affecting candicidin synthesis and mycelial growth of Streptomyces griseus IMRU 3570 were studied. Inorganic phosphate was found to inhibit candicidin synthesis but to stimulate mycelial growth. Zinc, iron, and magnesium ions stimulated candicidin synthesis at relatively high concentrations in a complex medium but not in a synthetic medium. No other factors studied, such as temperature, oxygen absorption rate, and sugar concentration, were found to differentially affect antibiotic synthesis and mycelial growth. Optimum concentration of inorganic phosphate for candicidin synthesis in a chemically defined medium was found to be between 5 × 10−5 and 5 × 10−4 M. The culture in idiophase stage can be reverted to typical trophophase growth by the addition of inorganic phosphate, suggesting the controlling role of inorganic phosphate in repression and derepression of secondary metabolic and primary metabolic activity of the culture. With a soya peptone-glucose medium, the maximum rate of candicidin production could be maintained and extended for a considerable length of time by controlling the culture pH at 8.0, using glucose to adjust the pH during the later stages of a batch fermentation. Carrying out fermentations in this way has given candicidin yields up to 4 g/liter.
PMCID: PMC429103  PMID: 806261

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