Tissue Pharmacologic and Virologic Determinants of Duodenal and Rectal Gastrointestinal-Associated Lymphoid Tissue Immune Reconstitution in HIV-Infected Patients Initiating Antiretroviral Therapy

Plasma, duodenal, and rectal tissue antiretroviral therapy (ART) drug concentrations, human immunodeficiency virus (HIV) RNA and HIV DNA copy numbers, and recovery of mucosal immunity were measured before and 9 months after initiation of 3 different ART regimens in 26 subjects. Plasma and tissue HIV RNA correlated at baseline and when 9-month declines were compared, suggesting that these compartments are tightly associated. Antiretroviral tissue:blood penetration ratios were above the 50% inhibitory concentration values in almost 100% of cases. There were no correlations between drug concentrations and HIV DNA/RNA. Importantly, no evidence was found for residual viral replication or deficient tissue drug penetration to account for delayed gastrointestinal-associated lymphoid tissue immune recovery.

Tissue-specific HIV-1 infection: why it matters

The human immunodeficiency virus displays a narrow tropism for CD4⁺ mononuclear cells, and activated CD4⁺ T lymphocytes are the main target. When these cells are depleted by viral replication, bystander apoptosis and increased cell turnover mediated by immune activation, there is a progressive immunodeficiency (i.e., AIDS). Despite this specific cell tropism, HIV-infected persons demonstrate pathology in nearly every organ system. This article reviews current understanding of tissue-specific HIV-1 infection in the CNS, the genital tract, and gastrointestinal-associated lymphoid tissue.