Immunological profile of periapical endodontic infections from HIV − and HIV + patients

Aim To evaluate CD 4 + CD 28 + and CD 8 + T‐cell genes and the gene expression of IFN ‐γ, TNF ‐α, IL ‐1‐β, IL ‐17A, IL ‐10, CCL ‐2/ MCP ‐1, CCL ‐4, CCL ‐5 ( RANTES ), CXCR 4, CCR 5 and RANKL from cells in the periapical interstitial fluid from root canal infections in healthy patients ( HIV −) and HIV ‐positive individuals ( HIV +). Methodology Subjects included 20 HIV − and 23 HIV + patients referred to the School of Dentistry at the Universidade Federal de Minas Gerais (Belo Horizonte, MG , Brazil). Almost all HIV + patients were undergoing highly active antiretroviral therapy ( HAART ). Clinical samples were taken from teeth with pulp necrosis, and no patients had acute periapical symptoms at the time of the appointments. After cleaning and drying, 3 paper points were introduced into the root canal, passing passively through the root apex (2 mm) into the periapical tissues for 1 min. The samples were collected immediately after root canal cleaning and 7 days later (restrained root canal bacterial load) to characterize those gene expressions using real‐time PCR . Results Significantly higher levels of CD 4 + CD 28 + and CD 8 + T cells in teeth with restrained bacterial loads (second collection) compared with the first collection were observed in both HIV − and HIV + samples. In HIV − patients, an increase in IL ‐10 and CXCR 4 expression was demonstrated as well as a decrease in pro‐inflammatory cytokines such as RANKL , IFN ‐γ, IL 1‐β and CCL 5. However, in HIV + patients an increase in cytokines IFN ‐γ, IL ‐1‐β, TNF ‐α and IL ‐17A, and chemokines CCL ‐2, CXCR 4 and CCR 5 were observed. The chemokine CCL ‐5 was not detected in HIV + individuals. Conclusions These findings suggest that after reducing the root canal bacterial load in HIV − individuals an anti‐inflammatory response is generated whilst in HIV + patients a pro‐inflammatory response is sustained in the periapical area.