Barcellini W, Sacerdote P, Borghi M O, Rizzardi G P, Fain C, De Giuli Morghen C, Manfredi B, Lazzarin A, Meroni P L, Panerai A E
Institute of Internal Medicine, University of Milan, Italy.
Peptides. 1994;15(5):769-75. doi: 10.1016/0196-9781(94)90028-0.
We investigated beta-endorphin (BE) content in an HIV-infected cell line and in peripheral blood mononuclear cells (PBM) from HIV-positive subjects. HIV infection increased BE content in HuT78 cell line compared to uninfected cells. Accordingly, BE content was greater in HIV-positive subjects than in healthy controls, both in fresh PBM and in mitogen-stimulated or unstimulated cultured cells. Further, in PHA-stimulated cultures, BE increase was correlated with disease progression. Opioids are known to decrease immune responsiveness in vivo, and it may be that the increased BE concentrations contribute to HIV-associated immune deficiency. In HIV-positive subjects, but not in healthy controls, intracellular BE concentration was positively correlated with PHA-induced PBM proliferation. The latter data suggest an alternative explanation: that the increased BE content represents a paradoxical response of the host in an attempt to balance virus-induced immunodepression. Thus, BE may be important in fine-tuning of the immune response with its up- and downregulation dependent upon differences in immune status.
