Effect of sublethal X-irradiation on the follicular trapping, with special references to radiosensitivity of follicle stramata in mouse lymph nodes non-stimulated and stimulated by phytohemagglutinin

Objective: The present study is to investigate the effect of sublethal whole body X-irradiation on the capacity of immune complex trapping in the draining popliteal lymph nodes (PLN) non-stimulated and stimulated by PHA. Methods: Immunohistochemistry and enzyme histochemistry were adopted in this experiment. Results: Two days after X-irradiation, at various intervals following HRP-anti-HRP complex injection, all of the PLN were found to have the follicular trapping capacity. By 6 days of X-irradiation, HRP-anti-HRP complexes could still be found in follicular area of all the lymph node at the first 15 min∼3.5 h by complex injection, but disappeared in non-stimulated-PLN and retained in the PLN stimulated by PHA at 24 h following complex injection. Conclusion: The damage to follicular trapping caused by sublethal whole body X-irradiation developed gradually with time after irradiation (about from 1 week on). The follicle stromata stimulated by PHA display a stronger radioresistance