Analysis Of HLA Mismatch Rate In Renal Transplantation And The Clinical Study Of The Relationship With Acute Rejection

Histocompatibility antigen, refered to the main related antigen when the transplanted graft was tolerated by the recipients after organ transplantation between different individuals, played the leading role which named main organization compatible antigen, for HLA (Human leukocyte antigens, Human HLA) in human. HLA played an important role in these respects such as antigen identification, presentation, immune response and regulation and so on, as the material base of mediated transplant rejection reaction, also as the important molecules to adjust immune response, called transplantation antigen. Immune rejection has a very important influence on the success of clinical organ transplants and it is the main reason causing the graft loss of function. HLA matching in organ transplantation has been developed from the traditional method of serology, cytology method to the technology of polymerase chain reaction (PCR). By using these methods for HLA matching between the donors and recipients can prevent and reduce immunological rejection.HLA is a group genes which located on the short arm of the 6th chromosome, HLA antigen should be classified according to product from different gene loci and its features. HLA genes can be divided into typeⅠ(HLA-A, B, C), typeⅡ(HLA-DR, DQ, DP), typeⅢ(C4A, C4B, C2, Bf) and other complement components. A large number of researches showed that HLAⅠandⅡantigens, especially HLA-A, B, DR had an important role in organ transplantation. In this paper, we just do the statistics of the HLA-A, B and DR antigen mismatch rate, because there were many researches about the relationship among the HLA-A, B and DR antigens, acute rejection and long-term graft survival, but few studies about relation with HLA-C antigens and acute rejection and long-term graft survival.For chronic renal failure and uremia patients, renal transplantation is an important method of clinical treatment for such diseases. However, rejection is still the major field of transplantation which is difficult to overcome in kidney transplantation, acute rejection (AR) is the most common complication after surgery, which usually occurs in 3 months after operation, the most in 1 to 3 weeks after operation, it also occurred in a few years. If you can get early diagnosis and proper treatment to AR, more than 90% of patients with AR can be reversed. AR is a high risk factor of chronic rejection (CR), and one of the most important risk factor, which leading to long-term graft survival failure and graft function loss. The importance of HLA matching on organ transplantation has been recognized by the international transplant community, the degree of HLA mismatches between donor and recipient is one of the main factors impacting long-term of graft survival. Good HLA matching helps preventing rejection and improving the successful rate of transplantation and graft survival. HLA antigen mismatch (MM) between donor and recipient is significantly affected the short-term results and postoperative long-term patient/graft survival. The lower HLA MM rate between donor and recipient, the lower of incidence of postoperative rejection,immunosuppressive drug consumption,postoperative infection and a low incidence of cancer, also the quality of life and patient/graft long-term survival is improved. At present,1-year survival rate of patient/graft after renal transplantation is 95%, and has reached the international advanced level, but lower long-term survival than abroad, higher HLA-MM rate between donor and recipient is one of the reasons for this. In this paper, we took polymerase chain reaction sequence specific primer amplification genotyping technique (polymerase chain reaction-sequences specific primer, PCR-SSP) to detect HLA-A,B,DR genetype of donor and recipient, to analysis HLA mismatch rate between donor and recipient of a large sample data in order to find a solution of the high mismatch rate in the clinical transplant centers, also to provide a clinical instruction significance. This study is divided into two chapters. (1) The analysis of human leukocyte antigen mismatch rate between donor and recipient in kidney transplant. (2) Clinical study of the relationship between HLA mismatch and acute rejection after renal transplantation.Chapter I The analysis of human leukocyte antigen mismatch rate between donor and recipient in kidney transplant.ObjectionTo analyse the HLA mismatch rate between donor and recipient in renal transplantation.Material and method1 Clinical material:6025 cases of renal transplant donors and recipients were divided into two groups:The first group is unknown group:3916 patients were waiting for kidney transplant recipients,2530 males patients,1386 females patients, aged from 7 to 81 years old; 1914 cases of renal transplant cadaveric donor, all of whom were healthy males, aged from 19 to 35 years old. The second group is known group:kidney transplant surgery has been accepted by 127 patients,90 males and 37 females, aged from 15 to 65 years; and 68 cadaveric donors, all healthy females, aged from 19 to 35 years old. The inclusion of the kidney transplant donors and recipients selected from the years 2000-01～2008-12, from organ transplant centers of total 36 hospitals, such as Nanfang Hospital, First Affiliated Hospital of Zhongshan university, Second Affiliated Hospital of Zhongshan university, and so on.2 Detect HLA-A, B, DR genetype of donor and recipient by taking polymerase chain reaction sequence specific primer amplification genotyping technique (polymerase chain reaction-sequences specific primer, PCR-SSP).3 Method of mismatch rate:According to the principles of HLA 6 antigen match: The two genes on the same antigen loci of the donor and recipient was identical, namely OMM; one of the genes on the same antigen loci is the same and the other is not, namely 1MM; the two genes on the same antigen loci were not the same, namely 2MM. The first group is unknown group, without considering basically on the matching of blood type,3916 cases of recipients and 1914 cases of donors for the composition of the maximum possible, N=3916* 1914, Statistics the probability of HLA-MM rate; The second group is known group,127 donor and recipient pairs which have accepted transplantation operation, N=127, MM between donor and recipient is the actual probability of transplant HLA-MM. Calculated HLA-A, B, DR 0 MM rate between donor and recipient at single site for the number of all 0 MM on the site of the donor and recipient pairs/N;1 MM rate is the number of the 1 MM between the donor and recipient/N;2 MM rate is the number of the 2MM between the donor and recipient/N. Calculation:0～2MM rate at HLA-A locus,0～2MM rate at B locus,0～2MM rate at DR locus in unknown group.0～2MM rate at HLA-A locus,0～2MM rate at B locus,0～2MM rate at DR locus and 0～6 MM rate of A,B,DR locus 6 antigens in known group.4 Statistical analysis:The direct calculation of 0～2 MM rate between donor and recipient at HLA-A,B,DR antigen locus;Comparison among the groups was calculated by chi-square test, P<0.05 indicated that there was significant difference between the groups, if the P value was less than 0.001, recorded as <0.001. All statistical calculations were performed by SPSS 13.0 statistical software to complete.ResultIn the Unknown group, the rates of 0 MM at HLA-A,B,DR locus were 9.14%. 2.19% and 3.69%.0 and 1 MM rate between the donor and recipient at HLA-A locus was 59.57%; 35.87% at HLA-B locus; 44.66%at HLA- DR locus. the rates of 0-6MM of HLA-A+B+DR 6 antigens in the known group between donor and recipient were 0,0.79%.5.51%.23.62%,27.56%.29.92% and 12.60%.0 to 2 MM rates were 6.30%(8/127), the 0 MM rate of HLA-A,B and DR locus were 9.45% 6.30% and 7.87%. The comparison of 0.1.2 MM rate at HLA-A locus between two groups has significant difference, all P<0.05. The difference of 0 MM and 2 MM rate at HLA-B locus between the two groups was significant (P<0.05), but there was no significant difference about 1 MM rate(P> 0.05); 0 and 2 MM rates at HLA-DR locus, there were significant difference between the two groups (P<0.05), but no significant difference in 1 MM (P> 0.05). Compared with UNOS data, random group had significant differences. In addition to 1MM at A sites and OMM at B sites, there were significant differences between the UNOS data and the known group.ConclusionThe rate of 0 mismatch Between unrelated donor and recipient at HLA-A,B,DR locus is very low, to find no HLA mismatch donor and recipient pairs is very difficult, the less HLA antigen mismatch numbers, the less numbers of donor and recipient pairs. Who will be randomly selected for the recipient would take a adverse effect.At present, there is still insufficient exist in HLA matching in renal transplantation in our country, the number of patients with better HLA matching is extremely scarce.The reason may be that kidneys had not allocated through the computer network by the center of the kidney transplantation in our country. For a single center, the numbers of donors and recipients were very limited, not sharing of resources, renal transplant recipients were difficult to get a good HLA matching. HLA mismatch rate between donor and recipient was high, to reduce the rate of HLA mismatch, it is necessary to establish national or regional organ sharing and distribution centers. The first time for the analysis of clinical practice of multi-center, a large random sample of study about HLA MM rate of kidney transplant recipient will provide some help.Chapter II Clinical study of the relationship between HLA mismatch and acute rejection after renal transplantation.Objective To analyse the relationship between HLA mismatch and acute rejection after renal transplantation.Material and method1 Clinical material:127 cases of patients which had accepted renal transplantation surgery, all were cadaveric renal transplantation.90 male patients and 37 females patients, aged from 15 to 65 years old. There were 114 cases of primary chronic glomerulonephritis,8 cases of hypertensive nephropathy,2 cases of poly cystic kidney and 3 cases of diabetic nephropathy in this group. There were 124 cases of fist time transplantation patients and 3 cases of second time transplantation patients. The warm ischemia time were 5-8 minutes, the cold ischemia time were 6-15h. Donors and recipients had the same blood type, CDC<5%.2 HLA matching:127 patients were performed strict HLA matching, in some sensitized patients, the HLA antigen of donors should be avoided the specific antibodies. All patients had HLA cross match,0 mismatch in 0 case,1 mismatch in 1 case,2 mismatch in 7 cases,3 mismatch in 30 cases,4 mismatch in 35 cases,5 mismatch in 38 cases,6 mismatch in 16 cases.3 Immunosuppresive protocol:Use of triple immunosuppressive regimen, CSA+ MMF/Rapa+Pred or FK506+MMF/Rapa+Pred.100ml 0.9% NaCl with 1.0g methylprednisolone (MP) was intravenously dripped during transplantation. And 0.5g, 0.25g,0.25g was give on the first,second,third day after transplantation.30mg prednisone was given orally and daily from the second day on, the does were reduced gradually. 100mg of ATG was used daily,3-5 consecutive days after transplantation. Mycophenolate mofetil(MMF) was used from the first day after transplantation, 0.5-0.75g MMF, twice a day. CSA or FK506 was used from the first day after transplantation, the trough CSA and FK506 blood concentration was 250-300ug/L and 8-12ug/L in the first month after operation.0.5g of MP was intravenously dripped for 3 consecutive days when AR occurred.5mg of OKT3 pulse treatment daily for consecutive days if the AR could not be reversed, maintain 3-5 days.4 The diagnostic standard of AR:AR should be considered when the following symptoms and examine results present:fever, hypourocrinia, elevated blood pressure, transplantation renal swelling or tenderness, renal pyramids swelling and/or vascular resistance index>0.8. Biopsy is needed to get pathological diagnosis when necessary.5 Method of statistics:The x2 tests were done to the rates of samples by SPSS 13.0 soft ware.ResultThe patients were followed up by 3 months, there were 23 cases patients in 127 patients occurred acute rejection in 1 month after renal transplantation. In HLA-OMM, 1MM and 2MM recipients, there were no AR occurred, While in 3MM 30 cases, 4MM 35 cases,5MM 38 cases and 6MM 16 cases, there were 3 patients (10%),5 cases (14.29%),9 cases (23.68%) and 6 cases (37.5%) occurred acute rejection in each group. As HLA mismatches between 0 to 3 for better matching as the first group, whereas HLA mismatch between 4 to 6 for poor matching as the second group. The incidence of acute rejection within 3 months after renal transplantation in first group were significantly higher than the second group (P=0.039).The incidence of the last two groups of acute rejection between the 0～2MM group,3～4MM group and 5～6MM group was significant difference.ConclusionFor a single transplant center, there was a lower chance to get a good HLA matching for kidney transplantation recipients. The patients who received a good HLA matching were significantly lower acute rejection than the matching lower group. The higher level of HLA mismatch between donor and recipient, the greater likelihood acute rejection occurred. Between donor and recipient, HLA MM was 3 can be used as the reference value of zero bound of selection of donor HLA matching.For the first transplant should be paid attention to HLA mismatch, lower rates of HLA MM, can significantly reduce the incidence of AR, improves the recovery of early graft function and improve graft survival and long-term survival.