Expression profile of human defensins in tonsils

Abstract

Defensins are cysteine-rich peptides with broad-spectrum antimicrobial activity by producing channels or micropores in the membrane, and expressed in plants, insects, birds, and mammals. They play an important role in innate immune systems because of their antimicrobial activity to fungi and enveloped viruses as well as bacteria. The human palatine tonsil is thought of as an important immune barrier. Both innate and adaptive immune systems cooperate in rejection of microorganisms. We hypothesized that defensins are expressed and play some role in the tonsil. However, the expression of human defensins in tonsils has hardly been studied. In the present study, the expression profile of six human alpha defensins (hαD) and three human beta defensins (hβD) was determined by reverse transcription-polymerase chain reaction (RT-PCR) assay in 20 tonsils, 2 jejunum mucosa and 1 peripheral blood sample. The transcripts of hαD-1 through 4, hβD-1, -2, and -3 were expressed in tonsils. This result suggests that these defensins play an important role in the innate defense mechanisms in tonsils.