African green monkeys (AGM) and other natural hosts for simian immunodeficiency virus (SIV) do not develop an AIDS-like disease following SIV infection. To evaluate differences in the role of SIV-specific adaptive immune responses between natural and nonnatural hosts, we used SIV(agmVer90) to infect vervet AGM and pigtailed macaques (PTM). This infection results in robust viral replication in b...

Allergic contact dermatitis (ACD) is driven by the activation and proliferation of allergen-specific memory T-lymphocytes and is currently diagnosed by patch testing with a selected panel of chemical allergens. The lymphocyte transformation test (LTT) can be used to monitor ex vivo T-lymphocyte responses to antigens, including contact allergens. The LTT is not viewed as being an alternative to ...

The effect of heritable LFA-1 deficiency on T lymphocyte function was measured. After primary mixed lymphocyte stimulation, all six patients studied showed diminished allospecific T lymphocyte cytolytic and NK activity as compared with kindred and normal controls. MLR and mitogen-induced proliferative responses were consistently depressed. LFA-1-deficient, EBV-transformed B cell lines were poor...

Xenogeneic lymphocytes can induce proliferative responses in the mixed lymphocyte culture (MLC) ~ which are as strong as those induced by allogeneic lymphocytes (1). It is impossible to determine directly which lymphocyte antigens stimulate the xenogeneic MLC response. The recently described "primed lymphocyte typing" (PLT) assay (2) has made it possible to determine indirectly the genetic cont...

BACKGROUND Changes in the blood lymphocyte composition probably both mediate and reflect the effects of natalizumab treatment in multiple sclerosis, with implications for treatment benefits and risks. METHODS A broad panel of markers for lymphocyte populations, including states of activation and co-stimulation, as well as functional T cell responses to recall antigens and mitogens, were asses...

Spleen cells from mice treated with cyclophosphamide (150 mg/kg) and cultured at suboptimal concentrations do not generate a cytotoxic T-lymphocyte (CTL) response to allogeneic tumor cells. The reduced response of spleen cells from cyclophosphamide-treated mice is not due to the elimination of CTL precursors because normal responses are obtained by the addition of a helper factor(s) derived fro...

Spleen cells from mice treated with Cyclophosphamide (150 mg/kg) and cultured at suboptimal concentrations do not gen erate a cytotoxic T-lymphocyte (CTL) response to allogeneic tumor cells. The reduced response of spleen cells from cyclophosphamide-treated mice is not due to the elimination of CTL precursors because normal responses are obtained by the addition of a helper factor(s) derived fr...

Sequential in vitro lymphocyte function tests in 13 patients undergoing cardiac operation were performed to study B lymphocyte function following operation. Lymphocytes were stimulated with phytohemagglutinin (PHA), pokeweed mitogen (PWM) and Staphylococcus aureus Cowan 1 (SAC). Mitogen responses were measured by 3H-labeled thymidine incorporation. The SAC responses were significantly depressed...

We have defined roles for the hemopoietic-specific Rho guanosine triphosphatase, Rac2, in B lymphocyte development and function through examination of rac2(-/-) mice. Rac2-deficient mice displayed peripheral blood B lymphocytosis and marked reductions in peritoneal cavity B-1a lymphocytes, marginal zone B lymphocytes, and IgM-secreting plasma cells as well as reduced concentrations of serum IgM...

Cytochalasin B, at concentration between 0.02 and 0.2 mug/ml, was slightly stimulatory to lymph-node cells from normal rats and greatly potentiated their response to phytohemagglutinin and low concentrations of concanavalin A (mitogens for thymus-derived lymphocytes); it also potentiated the response of thymocytes to phytohemagglutinin. The response of lymphnode cells to lipopolysaccharide endo...