Differences in viral distribution and cell adhesion molecule expression in the intestinal tract of rhesus macaques infected with pathogenic and nonpathogenic SIV.

We investigated SIV infection and expression of adhesion molecules in the small intestine of rhesus macaques infected with pathogenic SIV (SIVmac) or nonpathogenic clone (SIV1A11). There was a wider dissemination and marked difference in tissue localization of SIVmac relative to SIV1A11. Our results also indicate that viral pathogenicity is associated with increased migration of inflammatory cells expressing VLA-alpha 4, LFA-1 alpha, Mac-1 alpha, ICAM-1, and beta 2 integrin into the intestinal mucosa.