Gilbert A. Hill

Latex agglutination reactions between human chorionic gonadotropin and rabbit antibody.

Summary It has been shown that rabbit antibody may be formed to the antigen, Human Chorionic Gonadotropin (Antuitrin S). Polystyrene latex particles were found to serve as an agglutinable carrier for this antigen-antibody system. The possibility of using this agglutination test for HCG as a suitable test for pregnancy is being explored.

Immunization of Mice with polysaccharides of Histoplasma capsulatum.

Summary H. capsulatum strain G17 (M) polysaccharide was capable of producing active resistance against intravenously induced histoplasmosis in mice. However, mice immunized with a H. capsulatum whole yeast cell antigen showed greater resistance when the H. capsulatum polysaccharide immunized, whole cell immunized and nonimmunized control mice were challenged by the intravenous injection of known numbers of viable H. capsulatum yeast phase organism.

ANTIGENS OF BLASTOMYCES

The material to be reported stems from interest in the hypothesis that reagents more specific than those available might be prepared for use in serologic and skin test reactions involving systemic mycotic pathogens. The problem of specificity of skin test reagents is of prime importance because of evidence demonstrating that cross reactions may occur among individuals sensitive to histoplasmin, blastomycin, coccidioidin, and Emmonsin.l-K* Martin has presented the results of wide-ranging studies on various Blastomyces dermatitidis antigens.6-8 Soluble antigen, obtained by sonic vibration of yeast-phase cells of B. dermatitidis, yielded as satisfactory a complementfixation test antigen as entire yeast-phase cells, but had the advantage of solubility and ease of storage. A polysaccharide precipitated from yeast-phase cell extract was found to be serologically active as well as capable of stimulating a limited degree of resistance to disease in mice. The crude extracts, however, were not found to be of significant value as skin test antigens. We have further explored these areas and, in this report, present aspects of strain variation in B. dermatitidis and the comparison of serologic, skin-reactive, and immunogenic properties of polysaccharides prepared from different strains of this organism.

Effects of Cortisone, Ascorbic Acid and Piromen on Phagocytosis in Mice.∗†

Summary Cortisone, ascorbic acid and Piromen were tested in mice for their effect upon macrophage activity as determined from the splenic uptake of colloidal ThO2 and upon the phagocytic activity of leukocytes in the peritoneal cavity against Micrococcus aureus. Cortisone in high doses (0.1 to 1 mg every 12 hours) significantly enhanced phagocytic activity of both macrophages and leukocytes. Ascorbic acid in doses as high as 1 mg every 12 hours had no effect on the activity of macrophages but this dose did significantly enhance the phagocytic ability of leukocytes in the peritoneal cavity. Piromen (0.1 μg every 12 hours) significantly increased the phagocytic activity of both types of cells. However, doses above or below this value were without significant effect in either type of experiment. The more potent auxophagocytic agents (cortisone and Piromen) were without salutary effect when tested singly and in combination in protection experiments in mice challenged with predetermined doses of Klebsiella pneumoniae.

Serologic Analysis of Ehrlich Tumor-Cell Induced Ascites Fluid.∗

Summary Ascites fluid induced in mice by intraperitoneal injection of Ehrlich tumor cells contained specific antibody to S. typhimurium when mice were immunized against this organism. The serum and ascites were identical in their anticomplementary properties and neither contained detectable complement. The serum had normal properdin levels. but the ascites did not contain detectable properdin under the assay conditions employed.