Background: HIV-associated pulmonary disorders are the most frequent cause of AIDS-related deaths. Rhesus macaques infected with SIV–HIV (SHIV) recapitulate the human HIV-1 lung disease and provide an excellent working model to study the pathogenesis of the human syndrome. Lungs of macaques with SHIV-associated pneumonia have pathology involving macrophage and T cell infiltration that is often accompanied with concurrent opportunistic infections.
Objective: To explore the relationship between SHIV-associated respiratory disease and the expression of platelet-derived growth factor (PDGF) B chain (PDGF-B) and its cognate receptors, PDGF-Rα and PDGF-Rβ, which have been implicated in chronic inflammatory processes.
Methods: Lung tissues from 10 SHIV-infected rhesus macaques were evaluated for pathological changes and correlation of these lesions with PDGF-B/PDGF-R expression by real-time reverse transcriptase polymerase chain reaction and immunohistochemistry.
Results: Virus-associated pneumonia was associated with virus replication in macrophages in the lungs, enhanced recruitment of macrophages and mononuclear cells into the organ, and, occasionally, fibrosis. These changes were accompanied by upregulation of PDGF-B and its cognate receptors in the diseased tissue. Confocal microscopy identified SHIV-infected macrophages as one of the major cell types expressing PDGF-B and PDGF-Rα/β in the affected lungs.
Conclusion: These results suggest that PDGF and its cognate receptors play a critical role in the pathogenesis of pulmonary disease associated with this virus.
From the aDepartments of Microbiology, Immunology and Molecular Genetics, USA
bMolecular and Integrative Physiology, USA
cPathology & Laboratory Medicine, USA
dCenter for Biostatistics and Advanced Informatics University of Kansas Medical Center, Kansas City, Kansas, USA.
*Navneet K. Dhillon and Yongjun Sui contributed equally to the study.
Received 25 July, 2006
Accepted 27 October, 2006
Correspondence to Dr S.J. Buch, Department of Molecular and Integrative Physiology, 5000 Wahl Hall East, University of Kansas Medical Center, 3901 Rainbow Blvd, Kansas City, KS 66160. E-mail: firstname.lastname@example.org