Resting blood lymphocytes in vitro undergo transformation into large, blastlike, dividing cells following incubation with phytohemagglutinin (PHA), a plant lectin from Phaseolus vulgaris (1). Farnes et al. (2) found another phytomitogen in saline extracts of the plant Phytolacca americana (pokeweed). Although both PHA and the pokeweed mitogen (PWM) induce nonspecific transformation of lymphocyt...

Cellular immunity was investigated in 43 patients with multiple myeloma (MM) by assessing ,HTdR uptake induced by monocyte-dependent [CD3 monoclonal antibodies (MoAbs), phytohemagglutinin (PHA)] and monocyte-independent (CD2 MoAbs, ionomycin + phorbolester) stimulations. The former were evaluated in peripheral blood mononuclear cells (PBMNC) and purified T cells; the latter were evaluated in pu...

Human immunodeficiency virus 1 (HIV-1) isolation from peripheral blood mononuclear cells (PBMCs) allows retrieval of replication-competent viral variants. In order to impose the smallest possible selective pressure on the viral isolates, isolation must be carried out in primary cultures of cells and not in tumor derived cell lines. The procedure involves culture of PBMCs from an infected patien...

Interferon (IFN)-gamma, interleukin (IL)-10, IL-6, and tumor necrosis factor (TNF)-alpha were significantly increased in sera from Sicilian patients with acute boutonneuse fever (BF) compared with those of healthy controls. IFN-gamma levels dropped sharply within the second week after infection. IL-6, IL-10, and TNF-alpha levels gradually declined; in convalescent patients only were they in the...

BACKGROUND Cell proliferation is associated with the pathogenesis of cancer because it provides opportunities for accumulating genetic mutations. However, biomarkers of cell proliferation in response to environmental stimuli have not been adequately explored for breast cancer risk. METHODS In a case-control study of 200 breast cancer patients and 360 healthy controls, we investigated the asso...

The lymphocytes from eight patients with active visceral leishmaniasis (VL), a disease associated with marked immunologic dysfunction, were examined for ability to produce interleukin 2 (IL-2) and gamma interferon during in vitro cultivation. It was found that both IL-2 and gamma interferon production, in response to leishmania antigen, was absent during the active disease, but was restored aft...

Accessory cells and/or soluble factors, together with interleukin 2 (lL2). are required for the proliferation and differentiation of phytohemagglutinin (PHA)-activated T lymphocytes. Human T-lymphotropic virus. type I (HTLV-l). a human retrovirus isolated from patients with adult T cell leukemia. can transform T cells in vitro. We investigated the role of HTLV-l-transformed T cell lines as acce...

Colour polymorphism in vertebrates is usually under genetic control and may be associated with variation in physiological traits. The melanocortin 1 receptor (Mc1r) has been involved repeatedly in melanin-based pigmentation but it was thought to have few other physiological effects. However, recent pharmacological studies suggest that MC1R could regulate the aspects of immunity. We investigated...

Marrow stem cell lines from old donors and those from young controls gave equally rapid rates of colony growth on spleens of irradiated mice. Old and young stem cell lines competed equally well with chromosomally marked marrow stem cells from a young donor in producing cell types that are stimulated by bleeding; old cells competed 70% as well as young in producing cell types stimulated by phyto...

The effect of donor age on the rate of cell entry into the proliferating pool and subsequent cell cycle duration for peripheral lymphocytes stimulated by phytohemagglutinin (PHA) were examined by using the bromodeoxyuridine incorporation-differential staining technique. Distribution curves for the appearance of metaphase cells in successive generations as a function of culture time were obtaine...