The immunomodulatory effects of Pleurotus florida on cell-mediated immunity and secondary lymphoid tissues in Balb/c mice.

This study aimed to evaluate the immunomodulatory effects of Pleurotus florida on cell-mediated immunity in Balb/c mice. Aqueous extract of P. florida was isolated, lyophilized, and stored in refrigerator until application. Forty female Balb/c mice were randomly divided into seven test and one control groups. Four groups received 10, 20, 50, or 100 mg/kg/day of P. florida extract intraperitoneally, whereas three others received 200, 500, or 1000 mg/kg/day by oral administration. Moreover, the control group received the same volume of normal saline intraperitoneally. The treatments were continued once a day for 2 weeks. Then, delayed type hypersensitivity (DTH), viability of splenic cells, and histology of secondary lymphoid tissues were examined. The results showed that DTH responses were not affected by various doses of the P. florida in different routes. However, a significant decrease in splenic cells viability was observed in groups treated with intraperitoneal injection of 10, 20, and 50 mg/kg of the P. florida extract. In contrast, oral administration of 1000 mg/kg of the extract caused a significant increase in viability of splenic cells. Although atrophic changes in spleen and lymph nodes were observed in some peritoneal injected groups, some doses of oral administration were lead to hyperplastic changes. The results of this study indicated that the effects of P. florida on cellular responses depends on dose and route of administration.