Effects of HLA mismatch on cytomegalovirus reactivation in cord blood transplantation.

Although human leukocyte antigen (HLA) mismatch is often thought to be associated with a high incidence of cytomegalovirus (CMV) reactivation, it is not clear whether this process is mediated by HLA mismatch or other factors, such as acute graft-versus-host disease (aGVHD). Here we focused on cord blood transplantation (CBT) and examined the effects of HLA mismatch on the incidence of CMV reactivation while minimizing the effects of aGVHD. In a multivariate analysis considering aGVHD as a time-dependent covariate, a significant effect on the incidence of CMV reactivation was noted for HLA disparity (hazard ratio [HR]: 0.54 for 8/8 match compared with 3-allele mismatch) and development of aGVHD (HR: 1.26). Next, in an analysis excluding cases that developed aGVHD, the incidences of CMV reactivation for 8/8 match and 1-allele mismatch were low compared with those for other mismatches. These findings were supported by the multivariate analysis (HR: 0.49 for 8/8 match and 0.64 for 1-allele mismatch compared with 3-allele mismatch). Together, these results suggested that HLA mismatch was involved in CMV reactivation and was associated with high morbidity of opportunistic infection after CBT.

Biological significance of HLA locus matching in unrelated donor bone marrow transplantation.

We hypothesized that the compatibility of each HLA loci between donor and patient induced divergent transplant-related immunologic responses, which attributed to the individualized manifestation of clinical outcomes. Here, we analyzed 7898 Japanese pairs transplanted with T-cell-replete marrow from an unrelated donor with complete HLA allele typing data. Multivariable competing risk regression analyses were conducted to evaluate the relative risk (RR) of clinical outcomes after transplantation. A significant RR of HLA allele mismatch compared with match was seen with HLA-A, -B, -C, and -DPB1 for grade III-IV acute graft-versus-host disease (GVHD), and HLA-C for chronic GVHD. Of note, only HLA-C and HLA-DPB1 mismatch reduced leukemia relapse, and this graft-versus-leukemia effect of HLA-DPB1 was independent of chronic GVHD. HLA-DRB1 and HLA-DQB1 double (DRB1_DQB1) mismatch was revealed to be a significant RR for acute GVHD and mortality, whereas single mismatch was not. Thus, the number of HLA-A, -B, -C, -DPB1, and DRB1_DQB1 mismatches showed a clear-cut risk difference for acute GVHD, whereas the number of mismatches for HLA-A, -B, -C, and DRB1_DQB1 showed the same for mortality. In conclusion, we determined the biological response to HLA locus mismatch in transplant-related immunologic events, and provide a rationale for use of a personalized algorithm for unrelated donor selection.

Association of Takayasu arteritis with HLA-B 67:01 and two amino acids in HLA-B protein.

OBJECTIVE: Takayasu arteritis (TAK) is a rare autoimmune arteritis that affects large arteries. Although the association between TAK and HLA-B 52:01 is established, the other susceptibility HLA-B alleles are not fully known. We performed genetic association studies to determine independent HLA-B susceptibility alleles other than HLA-B 52:01 and to identify important amino acids of HLA-B protein in TAK susceptibility. METHODS: One hundred patients with TAK and 1000 unrelated healthy controls were genotyped for HLA-B alleles in the first set, followed by a replication set containing 73 patients with TAK and 1000 controls to compare the frequencies of HLA-B alleles. Step-up logistic regression analysis was performed to identify susceptibility amino acids of HLA-B protein. RESULTS: Strong associations of susceptibility to TAK with HLA-B 52:01 and HLA-B 67:01 were observed (P = 1.0 × 10(-16) and 9.5 × 10(-6), respectively). An independent susceptibility effect of HLA-B 67:01 from HLA-B 52:01 was also detected (P = 1.8 × 10(-7)). Amino acid residues of histidine at position 171 and phenylalanine at position 67, both of which are located in antigen binding grooves of the HLA-B protein, were associated with TAK susceptibility (P ≤ 3.8 × 10(-5)) with a significant difference from other amino acid variations (ΔAIC ≥ 9.65). CONCLUSION: HLA-B 67:01 is associated with TAK independently from HLA-B 52:01. Two amino acids in HLA-B protein are strongly associated with TAK susceptibility.

Stable renal engraftment in a patient following successful tandem autologous/reduced-intensity conditioning allogeneic transplantation for treatment of multiple myeloma with del(17p) that developed as a post-transplantation lymphoproliferative disease following renal transplantation.

Multiple myeloma (MM) developing after renal transplantation is rare. From January 1972 to December 2011, a total of 1,485 patients underwent renal transplantation in Nagoya Daini Red Cross Hospital; 14 (0.9%) of these recipients developed post-transplantation lymphoproliferative disorders (PTLDs) including two plasma cell neoplasms. Here, we report the clinical course of a 35-year-old male with immunoglobulin G k-type MM of recipient origin that developed 5 years after renal transplantation from a human leukocyte antigen (HLA)-haploidentical female sibling donor, which was performed to address dialysis-dependent chronic glomerulonephritis. Cytogenetic analysis revealed significant del(17p) abnormalities in myeloma cells. After non-response to bortezomib treatment, the patient achieved partial response with a thalidomide-containing salvage regimen and underwent successful tandem autologous/reduced-intensity conditioning allogeneic hematopoietic stem cell transplantation (HSCT) from an unrelated male donor matched for seven of eight HLAs. At the 8-month follow-up time point, the patient's performance status remained good, and the transplanted kidney remains functional without rejection. To the best of our knowledge, this is the first report of a successful use of allogeneic HSCT for a patient who developed MM as a PTLD after renal transplantation. This patient has a transplanted kidney and transplanted hematopoietic cells that currently coexist without rejection.

ACPA-negative RA consists of two genetically distinct subsets based on RF positivity in Japanese.

HLA-DRB1, especially the shared epitope (SE), is strongly associated with rheumatoid arthritis (RA). However, recent studies have shown that SE is at most weakly associated with RA without anti-citrullinated peptide/protein antibody (ACPA). We have recently reported that ACPA-negative RA is associated with specific HLA-DRB1 alleles and diplotypes. Here, we attempted to detect genetically different subsets of ACPA-negative RA by classifying ACPA-negative RA patients into two groups based on their positivity for rheumatoid factor (RF). HLA-DRB1 genotyping data for totally 954 ACPA-negative RA patients and 2,008 healthy individuals in two independent sets were used. HLA-DRB1 allele and diplotype frequencies were compared among the ACPA-negative RF-positive RA patients, ACPA-negative RF-negative RA patients, and controls in each set. Combined results were also analyzed. A similar analysis was performed in 685 ACPA-positive RA patients classified according to their RF positivity. As a result, HLA-DRB1*04:05 and *09:01 showed strong associations with ACPA-negative RF-positive RA in the combined analysis (p = 8.8×10(-6) and 0.0011, OR: 1.57 (1.28-1.91) and 1.37 (1.13-1.65), respectively). We also found that HLA-DR14 and the HLA-DR8 homozygote were associated with ACPA-negative RF-negative RA (p = 0.00022 and 0.00013, OR: 1.52 (1.21-1.89) and 3.08 (1.68-5.64), respectively). These association tendencies were found in each set. On the contrary, we could not detect any significant differences between ACPA-positive RA subsets. As a conclusion, ACPA-negative RA includes two genetically distinct subsets according to RF positivity in Japan, which display different associations with HLA-DRB1. ACPA-negative RF-positive RA is strongly associated with HLA-DRB1*04:05 and *09:01. ACPA-negative RF-negative RA is associated with DR14 and the HLA-DR8 homozygote.

A large-scale association study identified multiple HLA-DRB1 alleles associated with ACPA-negative rheumatoid arthritis in Japanese subjects.

BACKGROUND: HLA-DRB1 is associated with rheumatoid arthritis (RA). However, it has recently been suggested that HLA-DRB1 is only associated with patients with RA who have anticitrullinated peptide/protein antibodies (ACPA), which are specific to RA. OBJECTIVE: To elucidate whether specific HLA-DR alleles are associated with ACPA-negative RA development. METHODS: HLA-DRB1 typing was carried out in 368 Japanese ACPA-negative patients with RA and 1508 healthy volunteers as the first set, followed by HLA-DRB1 typing of 501 cases and 500 controls as the second set. The HLA-DRB1 allele frequency and diplotype frequency were compared in each group, and the results of the two studies were combined to detect HLA-DRB1 alleles or diplotypes associated with ACPA-negative RA. RESULTS: HLA-DRB1*12:01 was identified as a novel susceptibility allele for ACPA-negative RA (p=0.000088, OR=1.72, 95% CI 1.31 to 2.26). HLA-DRB1*04:05 and *14:03 showed moderate associations with ACPA-negative RA (p=0.0063, OR=1.26, 95% CI 1.07 to 1.49 and p=0.0043, OR=1.81, 95% CI 1.20 to 2.73, respectively). The shared epitope was weakly associated with ACPA-negative RA, but no dosage effect was detected (p=0.016, OR=1.17, 95% CI 1.03 to 1.34). A combination of HLA-DRB1*12:01 and DRB1*09:01 showed a strong association with susceptibility to ACPA-negative RA (p=0.00013, OR=3.62, 95% CI 1.79 to 7.30). Homozygosity for HLA-DR8 was significantly associated with ACPA-negative RA (p=0.0070, OR=2.16, 95% CI 1.22 to 3.82). It was also found that HLA-DRB1*15:02 and *13:02 were protective against ACPA-negative RA (p=0.00010, OR=0.68, 95% CI 0.56 to 0.83 and p=0.00059, OR=0.66, 95% CI 0.52 to 0.84, respectively). CONCLUSIONS: In this large-scale association study multiple alleles and diplotypes were found to be associated with susceptibility to, or protection against, ACPA-negative RA.

Anti-citrullinated peptide antibody-negative RA is a genetically distinct subset: a definitive study using only bone-erosive ACPA-negative rheumatoid arthritis.

OBJECTIVES: ACPA is a highly specific marker for RA. It was recently reported that ACPA can be used to classify RA into two disease subsets, ACPA-positive and ACPA-negative RA. ACPA-positive RA was found to be associated with the HLA-DR shared epitope (SE), but ACPA negative was not. However, the suspicion remained that this result was caused by the ACPA-negative RA subset containing patients with non-RA diseases. We examined whether this is the case even when possible non-RA ACPA-negative RA patients were excluded by selecting only patients with bone erosion. METHODS: We genotyped HLA-DRB1 alleles for 574 ACPA-positive RA, 185 ACPA-negative RA (including 97 erosive RA) and 1508 healthy donors. We also tested whether HLA-DR SE is associated with RF-negative or ANA-negative RA. RESULTS: ACPA-negative RA with apparent bone erosion was not associated with SE, supporting the idea that ACPA-negative RA is genetically distinct from ACPA-positive RA. We also tested whether these subsets are based on autoantibody-producing activity. In accordance with the ACPA-negative RA subset, the RF-negative RA subset showed a clearly distinct pattern of association with SE from the RF-positive RA. In contrast, ANA-negative as well as ANA-positive RA was similarly associated with SE, suggesting that the subsets distinguished by ACPA are not based simply on differences in autoantibody production. CONCLUSIONS: ACPA-negative erosive RA is genetically distinct from ACPA-positive RA.

[Early relapse of hemophagocytic syndrome after reduced-intensity cord blood transplantation for relapsed acute lymphoblastic leukemia].

We report a 4-year-old girl who presented with acute onset of hemophagocytic syndrome (HPS) after induction therapy and HPS relapsed immediately after reduced-intensity cord blood transplantation (RI-CBT) for relapse of acute lymphoblastic leukemia. The patient underwent CBT from 2 locus-mismatched donor, after reduced-intensity conditioning therapy consisting of fludarabine, melphalan, and total body irradiation 4Gy. Prednisolone and cyclosporine were administered for prophylaxis against graft-versus-host disease. Bone marrow examination on day 20 revealed activated macrophages displaying hemophagocytosis. The origin of macrophages was 2(nd) donor derived. After administration of steroids, intravenous immunoglobulin and VP-16, the patient exhibited complete chimerism and remained in complete remission for over one year.

Impact of highly conserved HLA haplotype on acute graft-versus-host disease.

Although the effects of human leukocyte antigen (HLA) locus matching on clinical outcome in unrelated hematopoietic stem cell transplantations have been characterized, the biologic implications of HLA haplotypes have not been defined. We demonstrated the genetic fixity of Japanese conserved extended haplotypes by multi-single nucleotide polymorphism analysis in 1810 Japanese donor-recipient pairs matching with HLA-A, -B, -C, -DRB1, and -DQB1 alleles. Three major Japanese conserved extended haplotypes (named HP-P1, HP-P2, and HP-P3) were essentially completely conserved at least in the 3.3-Mb HLA region from HLA-A to -DPB1, and extended far beyond HLA-A. The risk of acute graft-versus-host disease (GVHD) of these HLA haplotypes was assessed with multivariate Cox regression in 712 patients transplanted from HLA fully (HLA-A, B, C, DRB1, DQB1, and DPB1) matched unrelated donors. HP-P2 itself reduced the risk of grade 2 to 4 acute GVHD (hazard ratio [HR] = 0.63; P = .032 compared with HP-P2-negative), whereas HP-P3 tended to increase the risk (HR = 1.38; P = .07). Among 381 patients with HP-P1, HP-P1/P3 (HR = 3.35; P = .024) significantly increased the risk of acute GVHD compared with homozygous HP-P1. This study is the first to demonstrate that a genetic difference derived from HLA haplotype itself is associated with acute GVHD in allogeneic hematopoietic stem cell transplantation.

Donor killer immunoglobulin-like receptor (KIR) genotype-patient cognate KIR ligand combination and antithymocyte globulin preadministration are critical factors in outcome of HLA-C-KIR ligand-mismatched T cell-replete unrelated bone marrow transplantation.

We previously reported the potent adverse effects of killer immunoglobulin-like receptor (KIR) ligand mismatch (KIR-L-MM) on the outcome of T cell-replete unrelated hematopoietic stem cell transplantation (UR-HSCT) through the Japan Marrow Donor Program. Other UR-HSCT studies have yielded inconsistent results. To address this discrepancy, we evaluated candidate factors contributing to the effects of KIR-L-MM on transplantation outcomes in retrospectively selected hematologic malignancy cases with uniform graft-versus-host disease (GVHD) prophylaxis (n = 1489). KIR-L-MM in the graft-versus-host direction (KIR-L-MM-G) was associated with a higher incidence of acute GVHD (aGVHD; P < .002) and a lower overall survival (OS; P < .0001) only without the preadministration of antithymocyte globulin (ATG). Furthermore, in KIR-L-MM-G, the donor KIR2DS2 gene with the patient cognate C1 ligand was associated with a higher incidence of aGVHD (P = .012). Multivariate analysis by Cox proportional hazard models suggested that donor 2DS2 and ATG preadministration were critical factors in grade III-IV aGVHD (hazard ratio = 1.96; 95% confidence interval = 1.01-3.80; P = .045, and hazard ratio = 0.56; 95% confidence interval = 0.31-0.99; P = .047, respectively). These results indicate that the adverse effects of KIR-L-MM-G depend on combination of donor-activating KIR genotype-patient cognate KIR ligand type and no ATG preadministration, thereby suggesting the importance of these factors in UR-HSCT and in leukemia treatment using natural killer (NK) cell alloreactivity.

Human leukocyte antigen haploidentical hematopoietic stem cell transplantation: indications and tentative outcomes in Japan.

The stem cell banking system in Japan by the Japan Marrow Donor Program (JMDP) and Japan Cord Blood Bank Network (JCBBN) has provided increased opportunities for patients who might benefit from stem cell transplant from allogeneic sources but who lack human leukocyte antigen (HLA)-matched related donors. Nevertheless, most patients probably do not undergo transplantation because of the absence of suitable stem cell sources. To fulfill this potential need, the outcomes of transplants from HLA-mismatched relatives with or without T-cell depletion were retrospectively analyzed: the rates of engraftment and survival were insufficient in transplants with T-cell depletion, and the actual increase in transplantable donor numbers was small because only a single locus mismatched donor was the realistic choice in those without T-cell depletion. Since prophylaxis with tacrolimus reduced the incidence of grade I-IV acute graft-versus-host disease (GVHD) in HLA class I allele mismatched unrelated donors, we studied transplantation from HLA one haploidentical family donors who showed microchimerism of noninherited maternal antigens, without T-cell depletion but with tacrolimus prophylaxis. The rates of engraftment and survival in this circumstance were similar to those obtained with transplantation from HLA-matched sibling donors.

Human leukocyte antigens in Japanese patients with biliary atresia: retrospective analysis of patients who underwent living donor liver transplantation.

Biliary atresia (BA) is a neonatal obstructive cholangiopathy characterized by a fibrosclerosing obliteration of the extrahepatic bile duct. The aim of this study was to investigate the relationship between human leukocyte antigens (HLA) and susceptibility to BA. We retrospectively analyzed 392 Japanese patients with BA and without extrahepatic anomalies who underwent living donor liver transplantations at our institute. Healthy Japanese volunteers (n = 828) served as normal controls. A significant positive association was observed between BA and HLA-DR2 (39.0% of patients vs. 30.4% of controls, odds ratio = 1.46, p = 0.029). Two-locus analyses disclosed that DR2 was not independently associated with BA, but the increased frequency of HLA-A24 and -B52 reflected the linkage disequilibrium between -A24, -B52, and -DR2. Moreover, the frequency of the haplotype HLA-A24-B52-DR2 was significantly higher in patients with BA than in the general Japanese populations described in the literature (odds ratio = 2.20, p = 0.00124). These results indicate that the gene for BA susceptibility is in close linkage disequilibrium with the HLA-A24-B52-DR2 haplotype observed in the Japanese population. We speculate that a gene at the locus close to HLA plays an important role in the pathogenesis of BA.