Immune exhaustion is associated with development of cardiopulmonary disease in a non-human primate model of HIV-infection (HUM8P.340)

Abstract

Abstract Cardiopulmonary disease remains a leading cause of morbidity and mortality in HIV infection, despite widespread use of anti-retroviral therapies. Chronic inflammation due to ongoing viral replication may lead to immune exhaustion, a potential mechanism for the development of chronic obstructive pulmonary disease (COPD) and/or pulmonary arterial hypertension (PAH). Previously, we have shown that simian immunodeficiency virus (SIV) infection of macaques results in PAH and COPD. In the current study, we examined whether lymphocyte exhaustion and/or activation is associated with cardiopulmonary disease in SIV infection. Macaques were intravenously infected with SIVΔB670 (n=6, PAH study) or SHIV89.6P (n=11, COPD study). Blood and bronchoalveolar lavage (BAL) fluid cells from S(H)IV-infected animals were analyzed by flow cytometry. Serial pulmonary function testing and right heart catheterization were performed to assess pulmonary obstruction and mean pulmonary arterial pressure (mPAP), respectively. Increased effector memory CD8+ T (Tem) cells (CD95+CD28-) (p=0.008) and expression of programmed death-1 (PD-1), a marker of exhaustion (p<0.001), in the lung correlated with increased mPAP in SIV-infected macaques. Increased peripheral blood CD8+ Tem cells correlated with worse pulmonary function (p<0.001) in SHIV-infected macaques. These results support the hypothesis that HIV-related cardiopulmonary disease is associated with chronic immune activation and exhaustion.