Interferon and tumor necrosis factor responses of HIV+ patients as markers for monitoring of the AIDS progression.

The blood samples taken from 31 HIV+ and AIDS patients were used to study interferon (IFN) and tumor necrosis factor (TNF) responses. The IFN and TNF levels in plasma were determined. In the whole blood assay (whole blood diluted 1:10 with culture medium) Newcastle disease virus (NDV) and phytohemagglutinin (PHA) were used as cytokine inducers. Blood leukocytes of HIV+ patients produced significantly less IFN-alpha after NDV stimulation than the cells of healthy (HIV-) individuals. On the other hand, the production of IFN-gamma in response to PHA was impaired only in AIDS patients with stage CDC IV and CD4+ cell number < 200/microliters. These patients had also increased IFN levels in plasma. Particularly, the high level of IFN in plasma was frequently detected in patients with progressing AIDS with CD4+ cell number < 50/microliters. This type of IFN was identified as a mixture of acid-labile and acid-stable IFN-alpha. The IFN responses of HIV+ patients may be considered as markers for monitoring progression of AIDS and therapy.