PERIPHERAL-BLOOD FROM HUMAN-IMMUNODEFICIENCY-VIRUS TYPE 1-INFECTED PATIENTS DISPLAYS DIMINISHED T-CELL GENERATION CAPACITY

An organ culture chimera system was used to assess the effect of human immunodeficiency virus type 1 (HIV-1) infection on the T cell-generat ion capacity of precursors derived from human peripheral blood. Periph eral blood mononuclear cells from HIV-1-infected patients and uninfect ed controls were placed on fetal thymus lobes of NOD/LtSz-scid/scid mi ce. Blood from the HIV-1-infected patients consistently produced fewer CD4 and CD8 cells compared with blood from controls (P < .01). Additi on of zidovudine to the cultures did not alter this profile. Limit dil ution experiments suggested that there were fewer functional precursor s in the infected patients. These results were not dependent on the pa tient's level of peripheral CD4 cells; even samples from patients with normal CD4 cell counts were unable to generate T cells in organ cultu res. The results are consistent with a loss in the capacity of HIV-1-i nfected patients to produce functional T cell progenitors in their per ipheral blood.