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Biomedical subjects

J R David

Publications and source records attributed to J R David.

At least 253 records · Page 14Linked to original sources

The compartmentalization of antigen-reactive lymphocytes in desensitized guinea pigs.

A single injection of epsilon,DNP-Lys(7-10) can render previously sensitized guinea pigs specifically unreactive to subsequent intradermal challenge with that antigen. Antigen-reactive lymphocytes, as assayed by macrophage-migration in-inhibition or thymidine incorporation, were depleted from the peritoneal exudates of those animals. In contrast, it was intriguing to find that lymph node lymphocytes from such animals responded normally in the antigen-induced thymidine incorporation assay. These studies demonstrate a compartmentalization of antigen-reactive lymphocytes in desensitized animals which may account for the short-lived nature of this phenomenon.

Animals↗

Alterations of macrophage functions by mediators from lymphocytes.

Sensitized lymphocytes were incubated in vitro with the specific antigen Supernatants from these cultures were chromatographed on Sephadex G-100 columns. Supernatant fractions containing MIF, chemotactic factor, and lymphotoxin, but free of antigen and antibody, were incubated with normal peritoneal exudate macrophages. Macrophage adherence, phagocytosis, spreading, motility, and direct hexose monophosphate oxidation were enhanced, while protein synthesis was unaffected. Thus, antigen-stimulated lymphocytes secrete a factor or factors which enhance certain macrophage functions. Implications for models of cellular immunity and cellular hypersensitivity are discussed.

Amino Acids↗