Abstract: Domestic and foreign researches showed that the expression level of TLR4 was up-regulated in the patients with psoriasis and henoeh-schonlein purpura. Over activated signals of TLRs can lead to inflammatory response in the body, cause infiltration of large number of inflammatory cells and over release of cell factors, which may interfere with the self immune tolerance mechanism of body and lead to immune function disorder, including the imbalance of Th1/Th2 immune response. The immune response induced by TLR4 in the development of psoriasis and henoeh-schonlein purpura was reviewed.

Key words: TLR4, psoriasi, henoeh-schonlein purpura