CD45Exon4and6Gene Mutation Detection In Psoriatic Patients

Psoriasis is a chronic inflammatory, autoimmune diseases,which may damage theskin and joints. T-lymphocytes play an important role in the occurrence and thedevelopment process of the disease. Recent studies have shown that the CD45is the keyto normal lymphocyte signaling, which can change the expression of CD45and have asignificant impact on the immune function. Point mutations of the CD45gene canchange the composition of splice variants and involved in the occurrence of someautoimmune diseases[7]. The mutation of C�'A,at base59and C�'G, at base77inexon4of CD45gene cause the inactivation of the splicing silencer, which makeCD45RA increased and have relationship with multiple sclerosis and other autoimmunediseases[3，4]. The mutation of C�'G,at base138in exon6of CD45gene increase inactivated T cells CD45RO and secrete more IFN-γ[6],which can increase thesusceptibility of some immune-related diseases. The studies of Lecewicz-Toruń B[8]，Flytlie HA[9]，Alefacept[10]also showed the relationship between CD45RO andPsoriasis.Objective:In this study, we use DHPLC and ARMS-PCR methods to detectwhether the CD45gene exon4and6of Psoriasis patients exist the gene mutations. Wecan make clear that the gene polymorphism of CD45exon4and6of Psoriasis vulgarisand rich the content of the pathogenesis of Psoriasis.Methods:1. Collect the blood samples of Psoriasis patient and extract DNA fragments of theCD45gene.2.Design specific primers to amplify the CD45exon4and use DHPLC to analysisthe amplification products. 3. Sent the PCR amplification products to Beijing apparent Biotechnology Co.,Ltd.for DHPLC detection.4. Analysis the results of DHPLC detection.5..Design the specific primers of ARMS-PCR to amplify CD45exon6, classifythe amplification products and selected one case of each type for DNA sequenceanalysis.Results:1.PCR amplification products of CD45exon4with Psoriasis patients: Weextracted all the DNA samples and got the specific fragment of the expected size.2.DHPLC detection and DNA sequence analysis of PCR amplification products:DHPLC analysis showed that, none of the115samples have the abnormal two peaks.3.Results of ARMS-PCR: We divided the115samples into3types by gelelectrophoresis, the A138A type、the A138G typeand G138G type, the mutation rateaccount for38.2%.4.The mutation rate of A�'G, at base138in exon6of CD45gene have nosignificant difference in male an female population, in guttate psoriasis and plaquepsoriasis and the early group and later group.5.The patients with genetic family history have higher mutation rate than nogenetic family history patients, which means mutation were closely related to geneticfamily history.Conclusion:1.We found no mutation samples in exon4of Psoriasis patients’ CD45gene byDHPLC detection.2.The mutation of A�'G, at base138in exon6of Psoriasis patients’ CD45geneby ARMS-PCR method have been demonstrated, and the mutation rate account for38.2%.3. The mutation of A�'G, at base138in exon6of Psoriasis patients’ CD45genehave relationship with the patients who have family history.