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Biomedical subjects

S D Chaparas

Publications and source records attributed to S D Chaparas.

At least 73 records · Page 4Linked to original sources
PubMed1973

Comparison of strains of BCG. I. Antigenic analysis and tuberculin reactivity.

At least 10 of 11 demonstrable antigens in unheated culture filtrates of 12 vaccine strains of BCG were shared as determined in a reference antigen-antibody immunoelectrophoresis system. Filtrates from each of the BCG strains gave equivalent skin test reactions in homologously and heterologously sensitized guinea pigs. By these immunological parameters, the 12 BCG strains were remarkably similar.

Animals↗
PubMed1973

Virulence of six strains of Mycobacterium bovis (BCG) in mice.

The abilities of six strains of Mycobacterium bovis strain BCG to replicate in vivo and to cause spleen enlargement in the CDF(1) male mouse were compared. The strains were grown in synthetic medium and harvested soon after complete pellicles were produced on liquid medium. In addition, two freeze-dried commercially available preparations were tested. The comparisons were made on the basis of injecting equal numbers of colony-forming units. Strain differences were marked. The Brazil strain was most effective in stimulating spleen enlargement, and the Japan strain was the least effective. This correlated with the number of colony-forming units isolated from the spleen.

Animals↗
PubMed1970

Tuberculin-active carbohydrate that induces inhibition of macrophage migration but not lymphocyte transformation.

A tuberculin carbohydrate fraction, GAE, in sensitized animals induced a delayed type of skin reactivity and inhibited the migration of macrophages but failed to stimulate lymphocyte transformation in vitro. Tuberculin protein-containing fractions were active in each test. These results show that in vitro lymphocyte transformation is not necessarily a corollary of delayed type hypersensitivity.

Animals↗