Comparison of Immunomodulating Activities of Dendrobium devonianum and Dendrobium officinale In vitro and In vivo

Background and Objective: Dendrobium devonianum and Dendrobium officinale are widely used as Chinese medicinal materials and health foods.These two species have similar appearances and chemical constitutions. However, their immunomodulating activities have never been compared. This study aims to investigate and compare the immunomodulating activities of D. devonianum and D. officinale. Materials and Methods: Ten batches of D. devonianum and D. officinale were collected from different regions. The botanical origins of the species were authenticated by DNA sequence analysis and the total polysaccharide contents were determined to guarantee the quality of each batch. Their immunomodulating activities were evaluated and compared in vitro and in vivo by splenocytes proliferation and hydrocortisone-induced immunosuppressed mice, respectively. Results: The two species have significant different sequences of DNA ITS region but with very close polysaccharide contents. In vitro study showed that the aqueous extracts of the 10 batches of D. devonianum and D. officinale significantly stimulated splenocyte proliferation with no differences in efficiencies. Furthermore, oral administration of D. devonianum or D. officinale not only significantly alleviated hydrocortisone-induced leukopenia and spleen and thymus atrophy but also significantly increased macrophage phagocytosis and delayed-type hypersensitivity response (DTH) in mice. Conclusion: Dendrobium devonianum and D. officinale regulated the innate and adaptive immune responses in vitro and in vivo with no differences in efficiencies.