S. Pillet et al., Monocyte expression of adhesion molecules in HIV-infected patients: Variations according to disease stage and possible pathogenic role, LAB INV, 79(7), 1999, pp. 815-822
We used flow cytometry to study the expression of adhesion molecules at the
cell surface and actin polymerization of whole-blood monocytes in 35 HIV-i
nfected patients at different stages of the disease. Monocytes were activat
ed in vivo, as demonstrated by increased expression of the adhesion molecul
e CD11b/CD18, reduced L-selectin antigen expression, and increased actin po
lymerization. These abnormalities were present in asymptomatic patients wit
h CD4+ cell counts greater than 500/mu l and did not increase with disease
progression or Viral load. Sialyl-Lewis x and CD31 expression at the monocy
te surface was normal in asymptomatic and symptomatic non-AIDS patients. In
contrast expression of both molecules was strongly reduced in patients wit
h AIDS. This change, despite normal maximal CD11b/CD18 expression and norma
l maximal actin polymerization, could contribute to the increased susceptib
ility to bacterial infections in AIDS. In contrast enhanced monocyte activa
tion may promote their transendothelial migration in non-AIDS patients, pos
sibly explaining the macrophage infiltration that can occur early in the di
sease.