Intraepithelial gamma/delta T cells in duodenal mucosa are related to the immune state and survival time in AIDS

The proportion of T-cell receptor gamma/delta(+) cells and the CD4/CD8 ratio relative to all CD3(+) intraepithelial lymphocytes (IEL) were determined by immunofluorescence in duodenal mucosa of late-stage (mostly CDC IVC1/D) subjects (n = 21) infected with human immunodeficiency virus type 1 (HIV-1). The gamma/delta fraction (median, 14.2%; range, 1.7 to 59.8%) was increased (P < 0.03) compared with that in HIV- controls (n = 11; median 2.8%; range, 0.3 to 38%), Also, the number of gamma/delta(+) IEL per mucosal unit was increased (P < 0.05) in the HIV+ subjects (median, 11.1/U) compared with the controls (3.2/U), Approximately 100% of the gamma/delta(+) IEL were CD8(-), and most expressed the V delta 1/J delta 1-encoded epitope (median, 90.9%), The total number of CD3(+) IEL tended to be lower than in the controls (67.4 versus 72.9/U), Both the epithelium and the lamina propria contained mainly CD8(+) T cells, the median ratios of CD4(+) T cells being 1 and 7.6%, respectively, This result accorded with the reduced CD4 cell number in blood (median, 18 x 10(6)/liter), The HIV+ subjects had increased serum levels of neopterin and beta(2)-microglobulin (both P < 0.0001), probably reflecting immunostimulation, Serum neopterin and beta(2)-microglobulin were inversely related to duodenal gamma/delta IEL, particularly in the premortal group (r = -0.97 and r = -0.58, respectively), The increased gamma/delta IEL might reflect enhanced intestinal protection in late-phase HIV infection, Short survival expectancy (<7 months) was associated not only with high levels of neopterin and beta(2)-microglobulin but also with a reduced number of duodenal gamma/delta(+) cells (P < 0.03).