Expression Of CD43 Gene In Peripheral Blood Mononuclear Cells Of Patients With SLE

PrefaceCD43 (leukosialin) , which is also called sialophorin, is a heavily glycosylated surface molecule on T - lymphocyte and thymocytes, some B - lymphocytes, monocytes, neutrophils and platelets in human and rat. cDNA sequence of CD43 in human has been coloned and it locates in chromosome 16p11.2.CD43 seems to have multiple physiological function including its role in cell - cell repulsion and in signal transduction pathways of activated lymphocytes, monocytes and granulocyte. It may also function as intercell adhesion molecule 1 (ICAM - 1) .Since CD43 described by Williams, further study has been doing and it is found abnormal in various immunological defeciency diseases. Resently the relationship between CD43 and SLE was noted. In this paper, expression of CD43 gene in peripheral blood mononuclear cells of SLE patients and normal individuals was examined by using RT - PCR to investigate the relationship between SLE and CD43, then further learn the immunological cause of SLE and the role of CD43 in autoimmunity disease.Materials and MethodsPeripheral blood mononuclear cells were isolated from SLE patients and normal individuals as standard procedures, then total RNA was extracted with Trizol. After that, by means of RT - PCR, products of CD43 were obtained and analyzed with Chemi Imager 5500, Alpa Innotech, Inc. T -test treated data.Results1. Amply ing result of RT - PCR; 318bp amply ing band of β - actin and 496bp band of CD43 appear in all products.2. Expression level of CD43 gene in PBMC of patients with SUE; CD43 gene expression in PBMC of patients is significantly higher than in controls, t = 7.109, p<0.01.DiscussionSystemic lupus erythematosus ( SLE) , which is due to interaction between genetic, hormone and enviroment, is immunodeficiency disease.CD43, characterized by large transmembrane glycoprotein, is on leukocytes surface except rest B cell, bone marrow cell of embryonic phase and fetus liver cell. The mucin - like 234 amino acid extracellular domain is extensively 0 -glycosylated with 70-85 0 - linked carbohydrate chains and several N - linked carbohydrate chains. So far, we don't understand its function clearly, but the earlier study reported if its gene was broken, CD43 expression was interferred. During B cell activation and differentiating to immunoglobulin - producing cells, its expression is increased and played a role in terminal B cell activation. We studied the expression of CD43 gene in PBMC of active SLE patient and found its expression is higher than normal individuals. As we know, CD43 only expresses on active B cell surface, so our study suggested B cell in active SLE patients mainly remains active state. In murine model NZB/NZW F1 mice, Lp - 3 ( CD43 in murine) expresses on the B cells that produce rather anti - DNA IgG than anti - DNA IgM. So CD43 + cells contribute to auto - antibody in SLE. In peripheral blood of patients with SLE, CD45 " CD43+ B cells produce anti -DNA antibody with high dilution. In addition, the expression of CD40L on the active T cells in SLE patients was higher than in normal individuals. Usually, CD43 induces expression of CD40L on T cells. We predict the higher expression of CD43 results in CD40L rising.