Genomic full-length sequence of the novel HLA-B*56:94 allele.

HLA-B*56:94 differs from HLA-B*56:05:01 by two non-synonymous nucleotide substitutions in exon 1 and synonymous nucleotide substitutions in exon 1 and exon 2.

Genomic full-length sequence of the novel HLA-A*02:1100 allele.

HLA-A*02:1100 differs from HLA-A*02:01:01:01 by a single non-synonymous nucleotide substitution in codon 76 of exon 2.

Discovery of the HLA-DQB1*06:465 allele, a variant of HLA-DQB1*06:04:01:01.

HLA-DQB1*06:465 differs from HLA-DQB1*06:04:01:01 by a non-synonymous nucleotide substitution in codon 38.

Genomic full-length sequence of the novel HLA-DQB1*04:01:01:04 allele.

The sequence of HLA-DQB1*04:01:01:04 differs from HLA-DQB1*04:01:01:03 by four nucleotide deletion in intron 2.

The novel HLA-C allele, HLA-C*01:02:84 allele, identified in a solid organ transplantation donor.

HLA-C*01:02:84 differs from HLA-C*01:02:01:01 by one synonymous nucleotide substitution in codon 48.

The HLA-B*58:01:43 allele identified in a Korean individual awaiting hematopoietic stem cell transplant.

HLA-B*58:01:43 differs from HLA-B*58:01:01:01 by one synonymous nucleotide substitution in codon 197.

Identification of the novel HLA-A*11:423 allele by sequencing-based typing.

HLA-A*11:423 differs from HLA-A*11:01:01:01 by a non-synonymous nucleotide substitution in codon 170, changing Arginine to Lysine.

Identification of the novel HLA allele, DQB1*06:427 by next-generation sequencing method.

HLA-DQB1*06:427 differs from HLA-DQB*06:01:01:01 by a single non-synonymous nucleotide substitution in codon 83 of exon 2.

The novel HLA-C*06:325 allele identified in a Korean individual awaiting kidney transplantation.

HLA-C*06:325 differs from HLA-C*06:02:01:01 by a non-synonymous nucleotide substitution in codon 145, changing Arginine to Histidine.

Outcome of ABO-Incompatible Kidney Transplantation According to ABO Type of Transfused Plasma: Comparative Analysis Between "Universal" AB and Donor-Type Plasma.

OBJECTIVE: We compared the clinical outcomes of recipients of ABO-incompatible (ABOi) kidney transplantation (KT) according to the blood group of the plasma transfused. MATERIALS AND METHODS: We retrospectively analyzed the data of 60 recipients of ABOi-KT with blood type O and A or B donors. Demographic and clinical characteristics were compared between 2 groups of recipients: 1 group received AB plasma regardless of the donor's blood type (n = 30), and the other group received donor-type plasma (n = 30). RESULTS: There were no significant differences between the groups in terms of demographic characteristics. Transfusion of donor-type plasma was noninferior to transfusion of type AB plasma in terms of both rejection-free survival and rejection rate (P = .455, P = .335). CONCLUSION: There was no significant prognostic difference between the 2 groups. In terms of blood supply and inventory management, we suggest that the blood group of the plasma should match the donor's type.

Rh(D) Alloimmunization Risk After Rh(D)-Incompatible Solid Organ Transplantations in Rh(D)-Negative Recipients.

OBJECTIVES: Rh(D)-incompatible (Rh-i) solid organ transplantations are not considered for organ matching, but no consensus guidelines exist regarding the need for anti-D immunoglobulin (RhIG) prophylaxis. METHODS: We reviewed 35 Rh(D)-negative patients who had received Rh-i solid organ transplantation. We divided the patients into a RhIG-administered group and a nonadministered group. All patients also underwent an antibody screening test to assess Rh alloimmunization. Graft function was monitored with serum creatinine or bilirubin and kidney or liver biopsy whenever a rejection was suspected. Overall survival was also assessed. RESULTS: The median (range) age of transplant recipients was 48.5 (4-69) years, and 73.5% of patients were male. Median (range) follow-up time after transplantation was 60 (2-246) months. In the RhIG nonadministered group (n = 16), anti-D was not detected in any of the patients. More rejection episodes occurred in the RhIG-administered group among those undergoing kidney transplant (P = .0278). CONCLUSIONS: The low rate of Rh(D) alloimmunization is associated with the immunosuppressive state of the patients. RhIG prophylaxis seems to have no clinical benefit in Rh-i solid organ transplantation.

Is Cryoprecipitate-Reduced Plasma an Efficacious Replacement Fluid for Therapeutic Plasma Exchange for Patients with Thrombotic Microangiopathy? A Single-Center Retrospective Experience.

OBJECTIVE: We designed a study to compare the efficacy of cryoprecipitate-reduced plasma (CRP) and fresh frozen plasma (FFP), at the level of individual sessions, for treating refractory thrombotic microangiopathy (TMA) with therapeutic plasma exchange (TPE). MATERIALS AND METHODS: Platelet counts (× 10³/µL) and lactate dehydrogenase (LD; IU/L) levels were measured before and after each session. We compared the mean-percentage and absolute changes in platelet count and LD after each TPE session. RESULTS: The data from 33 patients treated for TMA between 2009 and 2018 were collected for this study. Both absolute and percentage increases in the platelet count were statistically significant (P = .003 and P = .011, respectively) when CRP was used. However, when patients were divided into subgroups according to specific diagnosis, no significant differences were found among the groups, except in terms of the absolute platelet count increase in the thrombotic thrombocytopenic purpura group (P <.001). CONCLUSION: The platelet count increase was higher when patients received CRP than when they received FFP. We found that CRP may be a rescue option for patients with refractory TMA.

Microparticle-tagged image-based cell counting (ImmunoSpin) for CD4 + T cells.

Affordable point-of-care (POC) CD4 + T lymphocyte counting techniques have been developed as alternatives to flow cytometry-based instruments caring for patients with human immunodeficiency virus (HIV)-1. However, POC CD4 enumeration technologies can be inaccurate. Here, we developed a microparticle-based visual detector of CD4 + T lymphocytes (ImmunoSpin) using microparticles conjugated with anti-CD4 antibodies, independent of microfluidic or fluorescence detection systems. Visual enumeration of CD4 + T cells under conventional light microscope was accurate compared to flow cytometry. Microparticle-tagged CD4 + T cells were well-recognized under a light microscope. ImmunoSpin showed very good precision (coefficients of variation of ImmunoSpin were ≤ 10%) and high correlation with clinical-grade flow cytometry for the enumeration of CD4 + T cells (y = 0.4232 + 0.9485 × for the %CD4 + T cell count, R2 = 0.99). At thresholds of 200 and 350 cells/µL, there was no misclassification of the ImmunoSpin system compared to the reference flow cytometry. ImmunoSpin showed clear differential classification of CD4 + T lymphocytes from granulocytes and monocytes. Because non-fluorescence microparticle-tags and cytospin slides are used in ImmunoSpin, they can be applied to an automatic digital image analyzer. Slide preparation allows long-term storage, no analysis time limitations, and image transfer in remote areas.

Hyperacute rejection in ABO-incompatible kidney transplantation: Significance of isoagglutinin subclass.

INTRODUCTION: ABO-incompatible transplantation has expanded the limited donor pool for kidney transplantation. Despite the successful desensitization protocols and immunosuppression, undesirable cases of hyperacute rejection occurs. OBJECTIVE: Flow cytometry was used to measure isoagglutinin titer and its IgG subclasses in assessment of the cause of hyperacute rejection in ABO-incompatible kidney transplantation. MATERIALS AND METHODS: The recipient was admitted for kidney transplantation due to end-stage renal disease. Pre-transplantation work-up for ABO-incompatible kidney transplantation included blood group typing, HLA DNA typing and HLA antibody analyses. HLA crossmatch analysis was conducted using donor lymphocytes and anti-HLA antibody assay using Luminex panel reactive antibody test (One Lambda, Inc., Canoga Park, CA). Desensitization protocol was composed of therapeutic plasma exchange sessions and rituximab. RESULTS: Despite negative HLA crossmatch results, a case of hyperacute rejection occurred after living donor kidney transplantation. Rejection resulted in immediate removal of graft, and the patient later received a second kidney transplantation. Retrospective evaluation of isoagglutinin titer and its subclasses using flow cytometry identified the cause of rejection to increased IgG1 subclass. Desensitization protocol for ABO-incompatible kidney transplantation now implements further caution for blood group O recipients. DISCUSSION: Hyperacute rejection resulting from increased IgG1 isoagglutinin subclass has not been previously confirmed using flow cytometry. Unfortunate outcome of this rejection case provides insight to how we should approach and ensure successful ABO-incompatible kidney transplantation.

Evaluation of safety of using incompatible plasma for therapeutic plasma exchange during shortage of AB plasma.

BACKGROUND: Criteria for selection of FFP blood type has not been clearly established and use of group AB plasma is preferred by numerous transplantation protocols. AIMS: This study assesses the safety and efficacy of alternative group A or B plasma in ABO incompatible solid organ transplantation. MATERIALS & METHODS: Alternative use of group A or B plasma (incompatible plasma) was inevitable during the shortage of group AB plasma. Experience from select number of patients during the period of extreme group AB plasma shortage is described. RESULTS: The result of alternative use of group A or B plasma was within expectation, showing effective reduction of isoagglutinin titers for pre-operative desensitization and efficacy for treatment of post-operative patients. No immediate hemolytic transfusion reaction was reported. DISCUSSION: While validation in a larger cohort of patients is necessary, our limited experience have shown satisfactory clinical outcomes without adverse events. CONCLUSIONS: Use of incompatible group A or B plasma is a viable option when group AB plasma is limited.

Prediction of HLA-DQ in Deceased Donors and its Clinical Significance in Kidney Transplantation.

BACKGROUND: HLA-DQ typing in deceased donors is not mandatory in Korea. Therefore, when patients develop DQ antibodies after kidney transplantation (KT) from deceased donor, it is impossible to determine whether they are donor-specific antibodies (DSA). We developed DQ prediction programs for the HLA gene and evaluated their clinical utility. METHODS: Two HLA-DQ prediction programs were developed: one based on Lewontin's linkage disequilibrium (LD) and haplotype frequency and the other on an artificial neural network (ANN). Low-resolution HLA-A, -B, -DR, and -DQ typing data of 5,603 Korean patients were analyzed in terms of haplotype frequency and used to develop an ANN DQ prediction program. Predicted DQ (pDQ) genotype accuracy was analyzed using the typed DQ data of 403 patients. pDQ DSA agreement, sensitivity, specificity, and false-negative rate was evaluated using 1,970 single-antigen bead assays performed on 885 KT recipients. The clinical significance of DQ and pDQ DSA was evaluated in 411 KT recipients. RESULTS: pDQ genotype accuracies were 75.4% (LD algorithm) and 75.7% (ANN). When the second most likely pDQ (LD algorithm) was also considered, the genotype accuracy increased to 92.6%. pDQ DSA (LD algorithm) agreement, sensitivity, specificity, and false-negative rate were 97.5%, 97.3%, 98.6%, and 2.4%, respectively. The antibody-mediated rejection treatment frequency was significantly higher in DQ or pDQ DSA-positive patients than in DQ or pDQ DSA-negative patients (P<0.001). CONCLUSIONS: Our DQ prediction programs showed good accuracy and could aid DQ DSA detection in patients who had undergone deceased donor KT without donor HLA-DQ typing.

Identification of 8-Digit HLA-A, -B, -C, and -DRB1 Allele and Haplotype Frequencies in Koreans Using the One Lambda AllType Next-Generation Sequencing Kit.

BACKGROUND: Recent studies have successfully implemented next-generation sequencing (NGS) in HLA typing. We performed HLA NGS in a Korean population to estimate HLA-A, -B, -C, and -DRB1 allele and haplotype frequencies up to an 8-digit resolution, which might be useful for an extended application of HLA results. METHODS: A total of 128 samples collected from healthy unrelated Korean adults, previously subjected to Sanger sequencing for 6-digit HLA analysis, were used. NGS was performed for HLA-A, -B, -C, and -DRB1 using the AllType NGS kit (One Lambda, West Hills, CA, USA), Ion Torrent S5 platform (Thermo Fisher Scientific, Waltham, MA, USA), and Type Steam Visual NGS analysis software (One Lambda). RESULTS: Eight HLA alleles showed frequencies of ≥10% in the Korean population, namely, A*24:02:01:01 (19.5%), A*33:03:01 (15.6%), A*02:01:01:01 (14.5%), A*11:01:01:01 (13.3%), B*15:01:01:01 (10.2%), C*01:02:01 (19.9%), C*03:04:01:02 (11.3%), and DRB1*09:01:02 (10.2%). Nine previous 6-digit HLA alleles were further identified as two or more 8-digit HLA alleles. Of these, eight alleles (A*24:02:01, B*35:01:01, B*40:01:02, B*55:02:01, B*58:01:01, C*03:02:02, C*07:02:01, and DRB1*07:01:01) were identified as two 8-digit HLA alleles, and one allele (B*51:01:01) was identified as three 8-digit HLA alleles. The most frequent four-loci haplotype was HLA-A*33:03:01-B*44:03:01:01-C*14:03-DRB1*13:02:01. CONCLUSIONS: We identified 8-digit HLA-A, -B, -C, and -DRB1 allele and haplotype frequencies in a healthy Korean population using NGS. These new data can be used as a representative Korean data for further disease-related HLA type analysis.

A comparison of the automated blood bank system IH-500 and manual tube method for anti-blood group antibody titration: a quantitative approach.

BACKGROUND: Anti-blood group antibody titers (ABTs) reported in titer values are variable depending on the testing method used. The introduction of new test methods such as automated methods requires proper method comparison. In this study, the automated blood bank system and manual tube method for ABT were compared using a log-transformed dataset to evaluate the alternative statistical approach. METHODS: ABT was conducted using specimens referred for solid organ transplantation. Methods for comparison were conventional manual tube method and IH-500 automated blood bank system using column agglutination (CAT). Criteria for agreement were exact match and 1-titer match. Measured titer values were log-transformed into interval scale for Deming regression analysis. RESULTS: From the comparison of the tube and CAT methods using titer values and the two criteria, the exact and 1-titer match were 15.9-41.5 % and 65.9-97.6 %, respectively. Deming regression was used to demonstrate the presence of both proportional and constant difference between the two methods. CONCLUSION: The method comparison using conventional statistical approaches had limits due to the semi-quantitative value of the test. Log-transformed interval scale values for comparison were useful for interpretation of method comparison datasets. This alternative statistical approach could contribute to a more accurate comparison between assays and standardization of ABT testing.

Confirmation of the recently described HLA-DPA1 allele, HLA-DPA1*02:02:08.

The HLA-DPA1*02:02:08 allele differs from HLA-DPA1*02:02:02:01 by a synonymous nucleotide substitution at codon 194.