Objective: To study the activation-induced cell death (AICD) in peripheral blood T-lymphocytes (PBL-T) from patients of hemorrhagic fever with renal syndrome (HFRS) and the effect of AICD on the pathogenesis of HFRS.
Methods: The PBL-T of patients with HFRS were isolated by negative selection with magnetic beads and cultured with or without phytohemagglutinin (PHA) and ionomycin. The apoptotic ratio of PBL-T was detected with TUNEL staining and assessed with flow cytometry. The level of caspase-3 of PBL-T in patients with HFRS was detected with Western blot. Characteristic gene fragment of Hantaan virus and Seoul virus was detected with reverse transcription polymerase chain reaction.
Results: In HFRS patients, the apoptotic ratio (27.79 +/- 0.99)% of PBL-T activated with PHA and ionomycin was significantly higher than that without activation (17.16 +/- 1.14)%, (P < 0.01). The apoptotic ratio of PBL-T in HFRS patients was higher than that of healthy control (P < 0.01), no matter with or without activation. The expression level of caspase-3 increased in the induced group of patients with HFRS and the expression level of 17 000 (the active component of caspase-3) increased significantly. The results of sequencing showed that amplification production from the serum are positive in 19 cases, seven being Hantaan virus and twelve Seoul virus.
Conclusions: AICD in PBL-T was found in patients of with HFRS. The high expression rate of caspase-3 in the PBL-T of patients with HFRS was related with AICD in the patients with HFRS. In the HFRS patients with specific IgM antibody positive, characteristic fragments can be obtained with RT-PCR from 79.2% patients. AICD of T lymphocytes may play an important role in the pathogenesis of HFRS.