sq-23377 and Cat-Diseases

Unstimulated lymphocytes from FIV-infected cats undergo spontaneous apoptosis in vitro as indicated by internucleosomal DNA fragmentation and hypodiploid DNA content of nuclei. Unlike what is reported in HIV-infected individuals, we observed that cell death of cat lymphocytes was inhibited by activation. Spontaneous apoptosis was reduced by the addition of cat serum and after activation by phorbol ester (PMA), superantigens (SEB, SEA), and to a lesser extent by mitogens such as concanavalin A and pokeweed mitogen. In contrast, apoptosis of lymphocytes from FIV-infected, but not from control cats was increased in the presence of calcium ionophore (ionomycin). Analysis of the phenotype of cells undergoing apoptosis revealed that cell death is not restricted to a cell subpopulation but involved all lymphocyte subsets. These data suggest that the mature lymphocytes of FIV-infected cats appear programmed to die by apoptosis unless rescued by specific agents, such as protein kinase C activators or mitogens.

Topics: Animals; Apoptosis; Bacterial Proteins; Cat Diseases; Cats; Concanavalin A; Exotoxins; Flow Cytometry; Immunodeficiency Virus, Feline; In Vitro Techniques; Ionomycin; Ionophores; Kinetics; Lentivirus Infections; Lymphocyte Activation; Lymphocyte Subsets; Lymphocytes; Membrane Proteins; Phenotype; Pokeweed Mitogens; Superantigens; Tetradecanoylphorbol Acetate