ABSTRACT
Major histocompatibility complex class Ⅰ chain related gene A(MICA) is located within the MHC class Ⅰ region of chromosome 6,including six exons.The MICA locus encodes membrane-bound polypeptides,similar with the classic class Ⅰ molecules,including three extracellular domains (α1,α2 and α3),a transmembrane domain,and a cytoplasmic tail,but is not associated with β2-microglobulin.MICA gene is expressed on endothelial cells,epithelial cells as well as most epithelial tumor cells surfaces,and are involved in the process of cell differentiation,proliferation and infiltration in a variety of tumor cells.Soluble MICA (sMICA) can be used as the prognosis predicting factor for some tumors.MICA gene plays an important role in the pathogenesis of a variety of malignant tumors,which might bring new ideas in prevention and treatment for malignant tumors.
ABSTRACT
Objective To study the influence of human leucocyte antigen(HLA) and major his-tocompatibility complex class Ⅰ chain-related gene A (MICA) specific antibodies on renal allograft function and graft rejective reaction by monitoring their changes from preoperative to postoperative pe-riods. Methods Twenty-seven patients with renal aliografts were tested with the specificity of anti-HLA antibodies (anti-HLA class Ⅰ and anti-HLA class Ⅱ) and anti-MICA antibodies and their posi-tive value changes by flow PRATM beads. The HLA genotype was integrated to distinguish donor specific antibody(DSA) and non-donor specific antibody(NDSA). Their serum creatinine levels and clinical data were analyzed simultaneously. Results Of the 27 patients, 22 cases accepted renal transplantation from dead bodies and 5 eases accepted from live donors. Except 1 failed patient, the other 26 patients had good functional renal allografts. Twenty-four survival patients were followed up on month 1, 3, 6 and 12 after transplantation. Seven out of 27 patients had pre-exist antibody before transplantation. Among them, 2 patients had anti-HLA antibody; 3 patients had anti-MICA antibody; 2 patients had both anti-HLA and anti-MICA antibody. Three patients with no anti-HLA and anti-MICA antibodies before transplantation created antibodies after transplantation from 3 to 6 months. One patient created NDSA after transplantation and appeared chronic rejection. There were 3 patients who had anti-MICA antibodies before transplantation. The expression levels of antibodies had changed from high to low, but the specific anti-MICA antibody had not changed during the follow-up on month 1, 3, 6 and 12 after transplantation. The patient with pre-transplantation low level of anti-HLA class Ⅱ antibody appeared acute rejection with fever and his CMV was positive as well. The patient's SCr levels changed from 171 μmol/L to 236 μmol/L after I to 3 months post-transplantation. Twenty-four patients were divided into positive and negative groups according to the specific antibody. There was significant difference of SCr levels between the 2 groups 1 month and 1 year after transplantation(P= 0.03, 0.05). Conclusions It is important to detect the specificity and positive value of anti-HLA antibodies and anti-MICA antibody regularly during the post transplantation follow-up. This will make an effective therapy for decreasing the occurrenee and development of acute or chronic rejection and hy-pofunction on renal allograft.
ABSTRACT
The (GCT)o polymorphism of the MICA gene was investigated in 100 patients with latent autoimmune diabetes in adult (LADA) and 145 healthy controls by PCR and denaturing polyacrylamide gel electrophoresis.The A5.1 allele was present at a significantly higher frequency in LADA group (0.340) than that in control group (0.183) (P