LAUSR

Abstract Polysaccharides are closely related to immune regulation, however, the effects of polysaccharides from different sources may be different. Therefore, the impact of a pectic heteropolysaccharides (TFPS) from the flowers of tea (Camellia sinensis L.) plant on immunoregulation and possible mechanisms were investigated by using cyclophosphamide (Cy)-induced BALB/c mice in the present study. TFPS especially at the dosage of 200 mg/kg·BW/d could stimulate the immunoreaction. TFPS could activate the colonic TLR4/MyD88/NF-κB p65 and JAK2/STAT3 pathways and enhance the expression of intestinal mucosal integrity genes including Claudin1, Claudin5 and Occludin1 at mRNA level, and histologically improve the intestinal barrier. TFPS remarkably reversed 69 of total 80 genera and 17 of 20 bacterial functional KEGG pathways related to immune system, and promoted the production of short-chain fatty acids in Cy-induced immunocompromised mice. The results indicate that gut health is crucial to host’s immunoreaction.