thymosin and AIDS-Related-Complex

The in vitro effects of thymosin fraction 5 (TF5) and lithium chloride (LiCl) on the ability of peripheral blood mononuclear cells (PBMC) obtained from 37 normal male donors and 33 male patients with AIDS-related complex (ARC) to respond to alloantigenic stimulation (mixed leukocyte reaction, MLR) and to produce interleukin 2 (IL-2) in response to mitogens were studied. TF5 significantly increased MLR responses in normal donors (P less than 0.01) and in a group of 33 ARC patients with depressed cellular immunity (P less than 0.05). Similar effects were observed when LiCl was added to the MLR assays in both the normal and the ARC patient groups. Furthermore, TF5 and LiCl exhibited additive immunoenhancing properties. In 10 normal donors TF5 enhanced phytohemaggutinin (PHA)-induced IL-2 production as well as IL-2 production in response to pokeweed mitogen (PWM) (P less than 0.02). TF5-mediated enhancement of IL-2 production by PBMC obtained from ARC patients was observed in response to both mitogens, i.e., PHA and PWM. Additionally, LiCl increased PHA-induced IL-2 production in both normal subjects and ARC patients. LiCl and TF5 together had an additive effect in the enhancement of IL-2 production in both groups of subjects. Our data extend previous observations regarding the immunoregulatory activities of TF5 and LiCl and provide evidence that PBMC obtained from ARC patients have the potential to respond in vitro to these agents. The significance of these findings is discussed.

Topics: Adult; AIDS-Related Complex; Cells, Cultured; Chlorides; Drug Synergism; Homosexuality; Humans; Interleukin-2; Lithium; Lithium Chloride; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Male; Middle Aged; Monocytes; Phytohemagglutinins; Pokeweed Mitogens; Stimulation, Chemical; Thymosin

A monoclonal antibody (anti-Tac) that appears to bind the receptor for interleukin-2 (IL-2) was used to quantitate lymphocytes that express IL-2 receptors (IL-2R) in response to phytohemagglutinin (PHA) stimulation. 62 +/- 4% of the cells expressed IL-2R in response to PHA in twelve normal subjects compared to 22 +/- 4% in fourteen patients with acquired immune deficiency syndrome (AIDS) (P less than 0.001) and 50 +/- 6% in six patients with AIDS-related complex (P less than 0.1). There was no effect on IL-2R expression, when lymphocytes from seven controls were incubated with IL-2 (20 mu/ml) or thymosin fraction V (10 mu/ml) for 72 h. However, when the lymphocytes from seven patients with AIDS were incubated with IL-2, the IL-2R rose from 18 +/- 3% to 31 +/- 3% (P less than 0.005) and with a fraction V to 29 +/- 3% (P less than 0.001). In addition, IL-2 augmented the PHA-induced proliferative responses in patients with AIDS-related complex and AIDS and normal controls, whereas thymosin fraction V had no significant effect. Thymosin fraction V also enhanced the IL-2 production of PHA-stimulated mononuclear cells obtained from six patients with AIDS and six normal controls. These results suggest that both IL-2 and thymosin fraction V can modulate in vitro T-cell function in patients with AIDS.

Topics: Acquired Immunodeficiency Syndrome; Adjuvants, Immunologic; AIDS-Related Complex; Humans; Interleukin-2; Lymphocyte Activation; Lymphocytes; Opportunistic Infections; Phytohemagglutinins; Receptors, Immunologic; Receptors, Interleukin-2; Thymosin