Waiting time for kidney transplantation based on calculated panel reactive antibodies: experience of a southern Brazilian center / Tempo de espera para transplante renal com base em painel de reatividade de anticorpos calculado: experiência de um centro do sul do Brasil

ABSTRACT Introduction: The aim of this study was to analyze the waiting list for kidney transplantation in our hospital according to candidate's panel reactive antibodies (cPRA) and its outcomes. Methods: One thousand six hundred forty patients who were on the waiting list between 2015 and 2019 were included. For the analysis, hazard ratios (HR) for transplant were estimated by Fine and Gray's regression model according to panel reactivity and HR for graft loss and death after transplantation. Results: The mean age was 45.39 ± 18.22 years. Male gender was predominant (61.2%), but the proportion decreased linearly with the increase in cPRA (p < 0.001). The distribution of patients according to panels were: 0% (n = 390), 1% - 49% (n = 517), 50% - 84% (n = 269), and ≥ 85% (n = 226). Transplantation was achieved in 85.5% of the sample within a median time of 8 months (CI 95%: 6.9 - 9.1). The estimated HRs for transplantation during the follow-up were 2.84 (95% CI: 2.51 - 3.34), 2.41(95%CI: 2.07 - 2.80), and 2.45(95%CI: 2.08 - 2.90) in the cPRA range of 0%, 1%-49%, and 50%-84%, respectively, compared to cPRA ≥ 85 (p < 0.001). After transplantation, the HR for graft loss was similar in the different cPRA groups, but the HR for death (0.46 95% CI 0.24-0.89 p = 0.022) was lower in the 0% cPRA group when adjusted for age, gender, and presence of donor specific antibodies (DSA). Conclusion: Patients with cPRA below 85% are more than twice as likely to receive a kidney transplantation with a shorter waiting time. The risk of graft loss after transplantation was similar in the different cPRA groups, and the adjusted risk of death was lower in nonsensitized recipients.

RESUMO Introdução: O objetivo foi analisar a lista de espera para transplante renal em nosso hospital segundo o painel de reatividade de anticorpos (PRAc) do candidato e seus desfechos. Métodos: Incluímos 1.640 pacientes em lista de espera entre 2015 e 2019. Para a análise, estimou-se a razão de risco (HR) para transplante pelo modelo de regressão de Fine e Gray conforme o painel de reatividade e HR para perda do enxerto e óbito após o transplante. Resultados: A idade média foi 45,39 ± 18,22 anos. Sexo masculino foi predominante (61,2%), mas a proporção diminuiu linearmente com o aumento do PRAc (p < 0,001). A distribuição de pacientes conforme os painéis foi: 0% (n = 390), 1% - 49% (n = 517), 50% - 84% (n = 269), e ≥85% (n = 226). O transplante foi realizado em 85,5% da amostra em tempo mediano de 8 meses (IC 95%: 6,9 - 9,1). As HRs estimadas para transplante durante o acompanhamento foram 2,84 (IC 95%: 2,51 - 3,34), 2,41 (IC 95%: 2,07 - 2,80) e 2,45 (IC 95%: 2,08 - 2,90) no intervalo de PRAc de 0%, 1%-49% e 50%-84%, respectivamente, comparadas com PRAc ≥ 85 (p < 0,001). Após o transplante, a HR para perda do enxerto foi semelhante nos diferentes grupos de PRAc, mas HR para óbito (0,46 IC 95% 0,24-0,89 p = 0,022) foi menor no grupo PRAc 0% quando ajustada para idade, sexo e presença de anticorpos doador específico (DSA). Conclusão: Pacientes com PRAc abaixo de 85% têm mais que o dobro de probabilidade de receber transplante renal com tempo de espera menor. Risco de perda do enxerto após o transplante foi semelhante nos diferentes grupos PRAc, e risco ajustado de óbito foi menor em receptores não sensibilizados.

Relación entre la compatibilidad del HLA y la pérdida del injerto en trasplante renal de donante cadavérico: Un análisis por propensity score matching en Colombia / Relationship between HLA compatibility and graft loss in renal transplant from a deceased donor: An analysis by propensity score matching in Colombia

Introducción. En Colombia, solo un 24 % de los pacientes en lista recibieron un trasplante renal, la mayoría de donante cadavérico. Para la asignación de órganos se considera el HLA A-B-DR, pero la evidencia reciente sugiere que el HLA A-B no está asociado con los desenlaces del trasplante. El objetivo de este estudio fue evaluar la relevancia del HLA A-B-DR en la sobrevida del injerto de los receptores de trasplante renal. Métodos. Estudio de cohorte retrospectivo que incluyó pacientes trasplantados renales con donante cadavérico en Colombiana de Trasplantes, desde 2008 a 2023. Se aplicó un propensity score matching (PSM) para ajustar las covariables en grupos de comparación por compatibilidad y se evaluó la relación del HLA A-B-DR con la sobrevida del injerto renal por medio de la prueba de log rank y la regresión de Cox. Resultados. Se identificaron 1337 pacientes transplantados renales, de los cuales fueron mujeres un 38,7 %, con mediana de edad de 47 años y de índice de masa corporal de 23,8 kg/m2. Tras ajustar por PSM las covariables para los grupos de comparación, la compatibilidad del HLA A-B no se relacionó significativamente con la pérdida del injerto, con HR de 0,99 (IC95% 0,71-1,37) para HLA A y 0,75 (IC95% 0,55-1,02) para HLA B. Solo la compatibilidad por HLA DR fue significativa para pérdida del injerto con un HR de 0,67 (IC95% 0,46-0,98). Conclusión. Este estudio sugiere que la compatibilidad del HLA A-B no influye significativamente en la pérdida del injerto, mientras que la compatibilidad del HLA DR sí mejora la sobrevida del injerto en trasplante renal con donante cadavérico

Introduction. In Colombia, only 24% of patients on the waiting list received a renal transplant, most of them from cadaveric donors. HLA A-B-DR is considered for organ allocation, but recent evidence suggests that HLA A-B is not associated with transplant outcomes. The objective of this study was to evaluate the relevance of HLA A-B-DR on graft survival in kidney transplant recipients. Methods. Retrospective cohort study that included kidney transplant recipients with a cadaveric donor in Colombiana de Trasplantes from 2008 to 2023. A propensity score matching (PSM) was applied to adjust the covariates in comparison groups for compatibility, and the relationship of HLA A-B-DR with kidney graft survival was evaluated using the log rank test and Cox regression. Results. A total of 1337 kidney transplant patients were identified; of those, 38.7% were female, with median age of 47 years, and BMI 23.8 kg/m2. After adjusting the covariates with PSM for the comparison groups, HLA A-B matching was not significantly related to graft loss, with HR of 0.99 (95% CI 0.71-1.37) and 0.75 (95% CI 0.55-1.02), respectively. Only HLA DR matching was significant for graft loss with an HR of 0.67 (95% CI 0.46-0.98). Conclusions. This study suggests that HLA A-B matching does not significantly influence graft loss, whereas HLA DR matching does improve graft survival in renal transplantation with a cadaveric donor.

Avanços no entendimento da patogenia da covid-19: uma revisão / Advances in understanding covid-19 pathogenesis: a review / Avances en la comprensión de la patogenia de la covid-19: una revisión

Introdução: O SARS-CoV-2, causador da pandemia por Doença por Coronavirus 2019 (COVID-19) gerou desafios à saúde pública, principalmente pelo conhecimento escasso de sua patogênese, e de estratégias terapêuticas e preventivas eficazes. Diversas lacunas de conhecimento sobre a doença envolvem a contribuição de fatores de risco, as doenças concomitantes, os fatores genéticos e imunogenéticos, no direcionamento da resposta imune, bem como a hiperinflamação, a imunidade antiviral e os alelos dos antígenos leucocitários humanos (HLAs) dos pacientes, que estão relacionados ao desfecho da doença. Objetivo: Esta revisão integrativa objetivou aprofundar os conhecimentos sobre os mecanismos de imunidade relacionada aos fatores de risco, da hiperinflamação e da tempestade de citocinas decorrente da infecção por SARS-CoV-2, bem como os avanços de associação dos HLAs nos agravos da doença. Metodologia: A revisão integrativa foi realizada utilizando os descritores nas bases de dados PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, Portal periódicos CAPES e Open Journal System, sem limites de janela cronológica. Resultados: Os efeitos da pandemia e os esforços na busca do conhecimento sobre a patogênese da COVID-19 resultaram em avanço no combate da doença. Conseguiu-se relacionar fatores de risco como obesidade, hipertensão, diabetes, doenças renais crônicas, idade, gênero, e outras condições predisponentes ao agravo da doença. Sob o aspecto da patogênese, também houveram progressos no entendimento dos mecanismos celulares e humorais em resposta à doença, bem como conseguiu vincular a resposta da hiperinflamação e o perfil dos HLAs dos pacientes à evolução da doença ao óbito ou à convalescência. Conclusão: Os esforços científicos conjuntos e os avanços na compreensão dos mecanismos da doença conseguiram estabelecer estratégias de combate a COVID-19, resultando no fim da pandemia, porém ainda há avanços que devem ser alcançados para o combate das sequelas dos pacientes convalescentes e para minimização da COVID longa e seus prejuízos.

Introduction: SARS-CoV-2, which causes the Coronavirus Disease 2019 (COVID-19) pandemic, has generated challenges to public health, mainly due to the limited knowledge of its pathogenesis and effective therapeutic and preventive strategies. Several gaps in knowledge about the disease involve the contribution of risk factors, concomitant diseases, genetic and immunogenetic factors, in directing the immune response, as well as hyperinflammation, antiviral immunity and human leukocyte antigen (HLAs) alleles of patients, which are related to the outcome of the disease. Aim: This integrative review aimed to deepen knowledge about the mechanisms of immunity related to risk factors, hyperinflammation and the cytokine storm resulting from SARS-CoV-2 infection, as well as advances in the association of HLAs in diseases. Methodology: The integrative review was carried out using the descriptors in the databases PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, CAPES periodical portal and Open Journal System, without chronological window limits. Results: The effects of the pandemic and efforts to seek knowledge about the pathogenesis of COVID-19 resulted in progress in combating the disease. It was possible to relate risk factors such as obesity, hypertension, diabetes, chronic kidney disease, age, gender, and other conditions predisposing to the worsening of the disease. From the aspect of pathogenesis, progress has also been made in understanding the cellular and humoral mechanisms in response to the disease, as well as linking the hyperinflammation response and the patients' HLA profile to the progression of the disease to death or convalescence. Conclusion: Joint scientific efforts and advances in understanding the mechanisms of the disease managed to establish strategies to combat COVID-19, resulting in the end of the pandemic, but there are still advances that must be achieved to combat the sequelae of convalescent patients and to minimize of long COVID and its losses.

Introducción: El SARS-CoV-2, causante de la pandemia de la Enfermedad del Coronavirus 2019 (COVID-19), ha generado desafíos a la salud pública, principalmente por el limitado conocimiento de su patogénesis y estrategias terapéuticas y preventivas efectivas. Varios vacíos en el conocimiento sobre la enfermedad involucran la contribución de factores de riesgo, enfermedades concomitantes, factores genéticos e inmunogenéticos, en la dirección de la respuesta inmune, así como la hiperinflamación, la inmunidad antiviral y los alelos del antígeno leucocitario humano (HLA) de los pacientes, que están relacionados con el resultado de la enfermedad. Objetivo: Esta revisión integradora tuvo como objetivo profundizar el conocimiento sobre los mecanismos de inmunidad relacionados con los factores de riesgo, la hiperinflamación y la tormenta de citocinas resultante de la infección por SARS-CoV-2, así como los avances en la asociación de los HLA en las complicaciones de la enfermedad. Metodología: La revisión integradora se realizó utilizando los descriptores de las bases de datos PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, portal periódico CAPES y Open Journal System, sin límites de ventana cronológica. Resultados: Los efectos de la pandemia y los esfuerzos por buscar conocimiento sobre la patogénesis de la COVID-19 resultaron en avances en el combate de la enfermedad. Se logró relacionar factores de riesgo como obesidad, hipertensión, diabetes, enfermedad renal crónica, edad, sexo y otras condiciones que predisponen al agravamiento de la enfermedad. Desde el punto de vista de la patogénesis, también se ha avanzado en la comprensión de los mecanismos celulares y humorales de respuesta a la enfermedad, así como en la vinculación de la respuesta de hiperinflamación y el perfil HLA de los pacientes con la progresión de la enfermedad hasta la muerte o la convalecencia. Conclusión: Los esfuerzos científicos conjuntos y los avances en la comprensión de los mecanismos de la enfermedad lograron establecer estrategias para combatir el COVID-19, teniendo como resultado el fin de la pandemia, pero aún quedan avances que se deben lograr para combatir las secuelas de los pacientes convalecientes y para Minimizar el COVID prolongado y sus pérdidas.

Banco de donantes voluntarios de células progenitoras hematopoyéticas. Proyecto Panama Dono

Introducción; El Trasplante de Células Progenitoras Hematopoyéticas es actualmente un tratamiento para diferentes desordenes hematológicos malignos y no malignos, que se efectúa cuando existe un receptor con un donante idéntico o haploidéntico para los genes del Complejo Mayor de Histocompatibilidad. En ausencia de donante familiar compatible, hemos creado el Programa de Donantes Voluntarios con tipificación del Sistema HLA. que han expresado su consentimiento de ser donantes y comparten los alelos del Sistema de linfocitos humanos codificados en el brazo corto del cromosoma seis. Materiales y métodos: El presente estudio es un estudio descriptivo, observacional y transversal que presenta los resultados de la búsqueda de donantes voluntarios para receptores sin donante familiar en el Programa Panamá Dono y su aplicación en Panamá. Resultado: De los grupos familiares estudiados que incluye receptor y donantes familiares, un total de 783 personas estudiadas aceptaron voluntariamente ser donantes no relacionados y sus tipificaciones HLA incorporadas al Programa Panamá Dono. Un total de 321 pacientes sin donante idéntico o haploidentico en su grupo familiar, se les ha buscado donante no relacionado en el Programa y se logró Trasplantar el primer receptor con un donante voluntario compatible en 16 genes del Complejo Mayor de Histocompatibilidad en el Hospital del Niño. Conclusión: El Laboratorio Nacional de Trasplante de la Caja de Seguro Social ha logrado crear el Programa de Donantes Voluntarios de Células Progenitoras Hematopoyéticas denominado PANAMA DONO, que consta de 788 panameños que han expresado su consentimiento. En la actualidad una paciente del Hospital del Niño fue trasplantada en 2022 con esta modalidad de donante compatible no relacionado. La compatibilidad idéntica de la receptora con el donante voluntario fue de 16 alelos idénticos del Complejo Mayor de Histocompatibilidad. (provisto por Infomedic International)

Introduction: Hematopoietic Progenitor Cell Transplantation is currently a treatment for different malignant and non-malignant hematological disorders, which is performed when there is a recipient with an identical or haploidentical donor for the genes of the Major Histocompatibility Complex. In the absence of a compatible family donor, we have created the Volunteer Donor Program with HLA System typing, who have expressed their consent to be donors and share the alleles of the human lymphocyte system encoded on the short arm of chromosome six. Materials and methods: The present study is a descriptive, observational, and cross-sectional study that presents the results of the search for volunteer donors for recipients without a family donor in the Panama Dono Program and its application in Panama. Results: Of the family groups studied, which included recipients and family donors, a total of 783 persons studied voluntarily accepted to be unrelated donors and their HLA typing incorporated into the Panama Dono Program. A total of 321 patients without an identical or haploidentical donor in their family group have been searched for unrelated donors in the Program and the first recipient was transplanted with a voluntary donor compatible in 16 genes of the Major Histocompatibility Complex in the Hospital del Niño. Conclusion: The National Transplant Laboratory of the Social Security Fund has managed to create the Program of Voluntary Donors of Hematopoietic Progenitor Cells called PANAMA DONO, which consists of 788 Panamanians who have expressed their consent. Currently a patient from the Hospital del Niño was transplanted in 2022 with this unrelated compatible donor modality. The identical compatibility of the recipient with the volunteer donor was 16 identical alleles of the Major Histocompatibility Complex. (provided by Infomedic International)

Role of HLA alleles polymorphism in systemic lupus erythematosus: A prospective study from North India

Background: Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder and has complex etiopathogenesis. The most appropriate hypothesis states that genetic susceptibility in the presence of environmental risk factors predisposes to SLE. HLA class II alleles are critical to immune response and are highly polymorphic. Various alleles in HLA-DR and -DQ regions were analyzed in SLE patients and healthy controls to see their role in susceptibility or protection to SLE. Materials and Methods: This was a prospective observational study, in which a total of 100 SLE patients and 100 controls were analyzed. HLA typing was done by polymerase chain reaction (PCR)-sequence-specific oligonucleotide (SSO) method (SSO probe). Results: DR?1*0301 was significantly increased in SLE patients when compared to controls and had the highest odds ratio. Other risk factor alleles found to be increased were DR?1*0701, DQ?1*0202, and DQ?1*0301, which had a significant positive association with SLE, suggesting their role in susceptibility to SLE. In contrast, DR?1*0401, DR?1*1401, DR?1*1404, DR?1*1501, DQ?1*0501, and DQ?1*0201 showed statistically significant reduction in SLE patients, while these were much more common in controls, suggesting their protective role. Conclusion: This study is only the second study in patients from North India and it determines the role of DR?1*0301, DR?1*0701, DQ?1*0202, and DQ?1*0301 alleles as risk factors in SLE patients.

Analysis of Gene Recombination between HLA-B and -DRB1, HLA-DQB1 and -DPB1 Loci / 中国实验血液学杂志

OBJECTIVE@#To investigate the recombinations within the human leukocyte antigen (HLA) region in two families.@*METHODS@#Genomic DNA was extracted from the peripheral blood specimens of the different family members. HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 loci were genotyped using polymerase chain reaction-sequence specific oligonucleotide probing technique (PCR-SSO) and next-generation sequencing technique. HLA haplotype was determined by genetic analysis of the pedigree.@*RESULTS@#The haplotypes of HLA-A*11:01~C*03:04~B*13:01~DRB1*12:02~DQB1*03:01~DPB1*05:01:01G and HLA-A*03:01~C*04:01~B*35:03~DRB1*12:01~DQB1*03:01~DPB1*04:01:01G in the family 1 were recombined between HLA-B and HLA-DRB1 loci, which formed the haplotype of HLA-A*11:01~C*03:04~B*13:01~DRB1* 12:01~DQB1*03:01~DPB1*04:01:01G. The haplotypes of HLA-A *02:06~C*03:03~B*35:01~DRB1*08:02~DQB1*04:02~ DPB1*13:01:01G and HLA-A *11:01~C*07:02~B*38:02~DRB1*15:02~DQB1*05:01~DPB1*05:01:01G in the family 2 were recombined between HLA-DQB1 and HLA-DPB1 loci, which formed the haplotype of HLA-A*02:06~C*03:03~B*35:01~ DRB1*08:02~DQB1*04:02~DPB1*05:01:01G.@*CONCLUSION@#The gene recombination events between HLA-B and -DRB1, HLA-DQB1 and -DPB1 loci were found respectively in two Chinese Han families.

Platelet Transfusion Strategies for MASPAT-Matched Platelet Transfusion Failed Patient with Allogeneic Hematopoietic Stem Cell Transplantation / 中国实验血液学杂志

OBJECTIVE@#To investigate the causes of ineffectiveness of platelet transfusion with monoclonal antibody solid phase platelet antibody test (MASPAT) matching in patients with allogeneic hematopoietic stem cell transplantation and explore the strategies of platelet transfusion.@*METHODS@#A case of donor-specific HLA antibodies (DSA) induced by transfusion which ultimately resulted in transplantation failure and ineffective platelet transfusion with MASPAT matching was selected, and the causes of ineffective platelet transfusion and platelet transfusion strategy were retrospectively analyzed.@*RESULTS@#The 32-year-old female patient was diagnosed as acute myeloid leukemia (high risk) in another hospital with the main symptoms of fever and leukopenia, who should be admitted for hematopoietic stem cell transplantation after remission by chemotherapy. In the course of chemotherapy, DSA was generated due to platelet transfusion, and had HLA gene loci incompatible with the donor of the first transplant, leading to the failure of the first transplant. The patient received platelet transfusion for several times before and after transplantation, and the results showed that the effective rate of MASPAT matched platelet transfusion was only 35.3%. Further analysis showed that the reason for the ineffective platelet transfusion was due to the missed detection of antibodies by MASPAT method. During the second hematopoietic stem cell transplantation, the DSA-negative donor was selected, and the matching platelets but ineffective transfusion during the primary transplantation were avoided. Finally, the patient was successfully transplanted and discharged from hospital.@*CONCLUSIONS@#DSA can cause graft failure or render the graft ineffective. For the platelet transfusion of patients with DSA, the platelet transfusion strategy with matching type only using MASPAT method will miss the detection of antibodies, resulting in invalid platelet transfusion.

Using Next-Generation Sequencing Technology to Confirm the HLA Rare Alleles Detected by PCR-SSOP / 中国实验血液学杂志

OBJECTIVE@#To confirm the HLA genotypes of the samples including 4 cases of magnetic bead probe HLA genotyping result pattern abnormality and 3 cases of ambiguous result detected by PCR sequence-specific oligonudeotide probe (SSOP) method.@*METHODS@#All samples derived from HLA high-resolution typing laboratory were detected by PCR-SSOP. A total of 4 samples of magnetic bead probe HLA genotyping result pattern abnormality and 3 samples of ambiguous result were further confirmed by PCR sequence-based typing (SBT) technology and next-generation sequencing (NGS) technology.@*RESULTS@#A total of 4 samples of magnetic bead probe HLA genotyping result pattern abnormality were detected by PCR-SSOP method. The results of SBT and NGS showed that the HLA-A genotype of sample 1 did not match any known genotypes. NGS analysis revealed that the novel allele was different from the closest matching allele A*31:01:02:01at position 154 with G>A in exon 2, which resulting in one amino acid substitution at codon 28 from Valine to Methionine (p.Val28Met). The HLA-C genotype of sample 2 was C*03:119, 06:02, sample 3 was C*03:03, 07:137, and sample 4 was B*55:02, 55:12. A total of 3 samples with ambiguous result were initially detected by PCR-SSOP method. The re-examination results of SBT and NGS showed that the HLA-B genotype of sample 5 was B*15:58, 38:02, sample 6 was DRB1*04:05, 14:101, and sample 7 was DQB1*03:34, 05:02. Among them, alleles C*03:119, C*07:137 and DRB1*14:101 were not included in the Common and Well-documented Alleles (CWD) v2.4 of the Chinese Hematopoietic Stem Cell Donor Database.@*CONCLUSION@#The abnormal pattern of HLA genotyping results of magnetic probe by PCR-SSOP method suggests that it may be a rare allele or a novel allele, which needs to be verified by sequencing.

HLA-B27 did not protect against COVID-19 in patients with axial spondyloarthritis - data from the ReumaCov-Brasil Registry

Abstract Background Some studies have suggested the HLA-B27 gene may protect against some infections, as well as it could play a benefit role on the viral clearance, including hepatitis C and HIV. However, there is lack of SARS-CoV-2 pandemic data in spondyloarthritis (SpA) patients. Aim To evaluate the impact of HLA-B27 gene positivity on the susceptibility and severity of COVID-19 and disease activity in axial SpA patients. Methods The ReumaCoV-Brasil is a multicenter, observational, prospective cohort designed to monitor immunemediated rheumatic diseases patients during SARS-CoV-2 pandemic in Brazil. Axial SpA patients, according to the ASAS classification criteria (2009), and only those with known HLA-B27 status, were included in this ReumaCov-Brasil's subanalysis. After pairing them to sex and age, they were divided in two groups: with (cases) and without (control group) COVID-19 diagnosis. Other immunodeficiency diseases, past organ or bone marrow transplantation, neoplasms and current chemotherapy were excluded. Demographic data, managing of COVID-19 (diagnosis, treatment, and outcomes, including hospitalization, mechanical ventilation, and death), comorbidities, clinical details (disease activity and concomitant medication) were collected using the Research Electronic Data Capture (REDCap) database. Data are presented as descriptive analysis and multiple regression models, using SPSS program, version 20. P level was set as 5%. Results From May 24th, 2020 to Jan 24th, 2021, a total of 153 axial SpA patients were included, of whom 85 (55.5%) with COVID-19 and 68 (44.4%) without COVID-19. Most of them were men (N = 92; 60.1%) with mean age of 44.0 ± 11.1 years and long-term disease (11.7 ± 9.9 years). Regarding the HLA-B27 status, 112 (73.2%) patients tested positive. There were no significant statistical differences concerning social distancing, smoking, BMI (body mass index), waist circumference and comorbidities. Regarding biological DMARDs, 110 (71.8%) were on TNF inhibitors and 14 (9.15%) on IL-17 antagonists. Comparing those patients with and without COVID-19, the HLA-B27 positivity was not different between groups (n = 64, 75.3% vs. n = 48, 48%, respectively; p = 0.514). In addition, disease activity was similar before and after the infection. Interestingly, no new episodes of arthritis, enthesitis or extra-musculoskeletal manifestations were reported after the COVID-19. The mean time from the first symptoms to hospitalization was 7.1 ± 3.4 days, and although the number of hospitalization days was numerically higher in the B27 positive group, no statistically significant difference was observed (5.7 ± 4.11 for B27 negative patients and 13.5 ± 14.8 for B27 positive patients; p = 0.594). Only one HLA-B27 negative patient died. No significant difference was found regarding concomitant medications, including conventional or biologic DMARDs between the groups. Conclusions No significant difference of COVID-19 frequency rate was observed in patients with axial SpA regarding the HLA-B27 positivity, suggesting a lack of protective effect with SARS-CoV-2 infection. In addition, the disease activity was similar before and after the infection. Trial registration This study was approved by the Brazilian Committee of Ethics in Human Research (CONEP), CAAE 30186820.2.1001.8807, and was registered at the Brazilian Registry of Clinical Trials - REBEC, RBR-33YTQC. All patients read and signed the informed consent form before inclusion.

HLA-B27 positivity in a large miscegenated population of 5,389,143 healthy blood marrow donors in Brazil

Abstract Background The prevalence of HLA-B27 gene positivity in healthy Caucasian communities varies between 8 and 14%. However, there is a lack of information in countries with a high rate of miscegenation, such as Brazil. Aim To estimate the frequency of HLA-B27 in the Brazilian general population using a large national registry database. Methods This is a cross-sectional ecological study using the Brazilian Registry of Volunteer Bone Marrow Donors (REDOME) database on HLA-B27 allelic frequency and proportion of positives of healthy donors (18-60 years old). Data were analyzed according to sex, age, race (by self-reported skin color recommended by the Brazilian Institute of Geography and Statistics - IBGE), and geographic region of residence. Results From 1994 to 2022, a total of 5,389,143 healthy bone marrow donors were included. The overall positivity for HLA-B27 was 4.35% (CI 95% 4.32-4.37%), regardless of sex and age (57.2% were women, mean age was 41.7yo). However, there was a difference between races: 4.85% in Whites; 2.92% in Blacks; 3.76% in Pardos (Browns i.e. mixed races); 3.95% in Amarelos (Yellows i.e. Asian Brazilians); and 3.18% in Indigenous. There was also a difference regarding geographic region of residence (North: 3.62%; Northeast: 3.63%; Southeast: 4.29%; Midwest: 4.5% and 5.25% in South). The homozygosity rate for the HLA-B27 was 1.32% of all the positives and only 0.06% in the general population. Conclusions Our findings provide the first Brazilian national prevalence for HLA-B27 in 4.35%. There is a gradient gene positivity from North to South, suggesting that the genetic background related to the miscegenation due to colonization, slavery, and some later waves of immigration together with internal migratory flows, could explain our findings.

Ambiguous results of the HLA-DPB1 genotyping results: Based on AllType NGS 11-loci sequencing reagent / 中国输血杂志

【Objective】 To statistically analyze the characteristics of ambiguous results of HLA-DPB1 genotyping given by AllType NGS 11-loci sequencing reagent via two next generation sequencing platforms, i. e. Ion Torrent S5 and Illumina Miseq. 【Methods】 A total of 434 samples from patients or donors were genotyped for HLA-DPB1 locus using AllType NGS 11-loci sequencing reagent from One Lambda company; 336 samples of them were sequenced via the Ion Torrent S5 platform and other 98 samples were sequenced via the Illumina Miseq platform. All 434 samples were genotyped for HLA-DPB1 gene simultaneously using PCR-SSO flow fluorescent bead method. The ambiguous genotypes of HLA-DPB1*13∶01∶01/107∶01 were distinguished by Sanger sequencing. The HLA-DPB1 genotype results by NGS method were assigned by TypeStream Visual professional software, and the ratio of ambiguous combination was calculated by direct count method. 【Results】 Ambiguous results were found in 357 out of 434 samples, accounting for 82.3% (357/434) when HLA-DPB1 allele was assigned to the third field using NGS method. Ambiguous results with 45 types were given in 275 out of 336 samples by the Ion Torrent S5 platform, accounting for 81.8% (275/336) and 82(with 27 types) out of 98 samples by the Illumina Miseq platform, accounting for 83.7% (82/98). All samples were re-genotyped for HLA-DPB1 gene by PCR-SSO, and none HLA-DPB1 allele had been missed by NGS. A total of 43 ambiguous alleles in HLA-DPB1*13∶01∶01/107∶01 involving 41 samples were distinguished by Sanger sequencing; HLA-DPB1*13∶01∶01 were detected in 25 (58.1%, 25/43) and HLA-DPB1*107∶01 in 18 (41.9%, 18/43). 【Conclusion】 There were still a high proportion of HLA-DPB1 ambiguous combinations using the AllType NGS 11-loci sequencing reagent. Sequencing exon 1 of HLA-DPB1 gene by Sanger sequencing can resolve part of the ambiguous results in HLA-DPB1*13∶01∶01/107∶01 alleles.

Molecular genetics research of a Chinese family carrying triple HLA-A alleles / 中国输血杂志

【Objective】 To determine molecular basis of a rare HLA-A typing results carrying triple A alleles in potential allo-HSCT donor and her family. 【Methods】 HLA-A, -B, -C, -DRB1, -DQB1, -E, -F, -G of 5 members in the family were genotyped at a high-resolution level using next-generation sequencing (NGS). HLA-A of probosita was re-checked using polymerase chain reaction-sequence-based typing (PCR-SBT), and SNP oligonucleotide probes (SNP-array)were scanned with genomic DNA of probosita. 【Results】 There was 162.9Kb duplication in 6p22.1(29, 803, 377-29, 966, 301)of probosita who carried triple A alleles A*02∶01∶01, A*11∶01∶01, A*24∶02∶01. Other two family members were found to carry this haplotype: A*02∶01∶01, A*24∶02∶01, B*54∶01∶01, C*01∶02∶01, DRB1*04∶05∶01, DQB1*04∶01∶01, E*01∶01∶01∶03, F*01∶01∶01, G*01∶01∶01∶01, which as a Mendelian gene was segregated and stably transmitted through two generations. 【Conclusion】 Tiny gene duplication induces one haplotype carries two HLA-A alleles in a potential healthy donor for allo-transplantaion and stably transmits through two generations.Routine HLA typing laboratories should pay more attention to this situation and accurately report.

Causes of HLA-A2 reactive antibodies and analysis of their eplets / 中国输血杂志

【Objective】 To analyze differences of eplets between the patient who generated HLA allele-specific antibodies after platelet transfusion with donors. 【Methods】 The HLA genotypes of the patient and donors were detected by PCR-SBT, and the Luminex single antigen beads coating was used to screen HLA-Ⅰ antibodies in the patient’s serum. HLA Matchmaker was utilized to analyze different amino acids and eplets. 【Results】 The patient carried HLA-A*02∶03 allele, and HLA-A2 antibodies were found in his serum after platelet transfusion (A*02∶01, A*02∶06, and A*02∶07). Sequence alignment showed that the patient′s A*02∶03 has a difference in position 149, which resulted in a different eplet between A*02∶03 and A*02∶01, A*02∶06, A*02∶07 and then induced the production of antibodies. 【Conclusion】 HLA antibodies are specific for HLA epitopes that have structural differences due to amino acid differences between HLA alleles, suggesting that high-resolution typing of HLA-A, -B need to be conducted in patients and donors, and the acceptable mismatch of HLA should be determined based on epitopes rather than antigens, so as to reduce alloimmune response and improve platelet count after transfusion.

Matching strategy for patients with platelet transfusion refractoriness caused by compound antibodies against HLA and CD36 / 中国输血杂志

【Objective】 To search compatible and suitable platelets for platelet transfusion refractoriness (PTR) patient caused by compound antibodies against HLA and CD36. 【Methods】 ELISA method was used to detect the antibody against platelet antigens and the specificity of HLA-I antibody in PTR patients. The specificity of HLA-I antibody and corresponding epitopes of patients were analyzed using MATCH IT! and HLA Matchmaker software. The HLA genotype of both donor and patient was obtained by HLA-SSO method. Compatible or suitable donor platelets for PTR patients were searched through cross-reactive group (CREG) of HLA-I and HLA epitope-matched approach (Eplet). The matching degree was identified using monoclonal antibody-specific immobilization of platelet antigens (MAIPA) and the platelet suspension immunofluores-cence test (PIFT). Finally, the transfusion effect was evaluated according to the corrected count increment (CCI). 【Results】 Compound antibodies against both CD36 and HLA-I antigens were detected in two PTR patients, and their phenotype of CD36 was conformed to be type I deficient. Through LSA testing, high-frequency of HLA -I antibodies was found in these two patients, and the panel reactive antibody in patients 1 and 2 was 56% (54/96) and 53% (51/96), respectively. According to HLA-CREG and Eplet matching strategies, one donor of grade C-matching with patient 1 and one donor of grade D-matching with patient 2 were screened from the CD36 deficiency donor bank, respectively. And the selected donors avoided the antigen of HLA-I antibody epitope. These results of MAIPA and PIFT also confirmed that no immune response was detected between the patient and the donor. And a CCI of >4.5 within 24 hour of transfusion of compatible platelets was obtained in patient 2. 【Conclusion】 For PTR patients caused by HLA and CD36 compound antibodies, a combination strategy including serological cross-matching, HLA-CREG and Eplet approach should be used to select the CD36 deficient donor platelets which evaded the antigen corresponding to HLA-I antibodies and had the compatible HLA epitopes.

Study on the extensibility of platelet donor gene database in Shaanxi / 中国输血杂志

【Objective】 To analyze the commonality and characteristics between voluntary blood donors and hematopoietic stem cell donors in this region, and explore the potential for integration and development between China Marrow Donors Program (CMDP) and voluntary blood donors, especially platelet donor databases, so as to improve recruitment success rate and inventory rate. 【Methods】 The database modeling and comparison methods were used to screen and stratify the matching and integration degree between the voluntary blood donors in recent 10 years and the marrow donors in the Shaanxi Branch of CMDP. The frequencies of HLA-A,-B alleles, HPA alleles and haplotypes were calculated with Arlequin 3. 5. 2. 2 software, and the matching probability of different platelet donor reserve pools was conducted according to the phenotypic frequencies. 【Results】 Among the voluntary donors with known HLA genotypes in this region, according to their blood donation behavior,the active blood donors excavated were divided into the first, second, third and fourth echelons of platelet donor reserve pools, with 696, 2 752, 9 092 and 12 028 donors, respectively. The first echelon had the highest proportion of 10-50 times of platelet donations and 10-20 times of whole blood donations, with 13.65% and 26.01%, respectively. The second echelon had 10-20 times of whole blood donations and 10-50 times of platelet donations, accounted for 15.04% and 1.38%, respectively, which were significantly different from other echelons' blood donation characteristics (P<0.05). With a database size of the existing platelet donor bank adding the first and second echelons (n=4 955), there was a 69.02% probability of matching at least one donor with matching HLA-A-B phenotype. When considering the matching ABO and HPA phenotypes, the probability of finding at least one donor with fully matching HLA, HPA and ABO isotype (type B as an example) was 48. 73%. 【Conclusion】 The three groups of whole blood donation, apheresis platelet donation and marrow donation in Xi'an area have a large cross-distribution. Compared with expanding the storage capacity from scratch, the active blood donors in CMDP database are the largest back-up force of platelet donors. While expanding the effective storage capacity, it can minimize the cost of building platelet donor bank and the demand for resources.

Viral selection pressure and CD4+T cell epitope in HLA-DRB1 * 11:01 of HCV infected patients / 中国输血杂志

【Objective】 HLA-DRB1 * 11:01, as a class HLA-Ⅱ gene, was reported to be associated with spontaneous clearance of HCV in Han and Li population. Our study was to investigate the effects of viral selection pressure and CD4+T cell epitope on the natural outcome of HCV infection in HLA-DRB1 * 11:01 positive infected patients. 【Methods】 The positive selection sites and population growth of E1E2 and NS3 genes of common HCV 6a in HLA-DRB1 * 11:01 positive and negative groups in Guangdong were respectively analyzed. The peptide library covering the conserved regions of common HCV genotypes was used to stimulate HCV spontaneous clearance group and chronic infection group using ELISPOT method. Reactive peptides were obtained according to the number of spot-forming cells per well and the frequency of occurrence in different groups. 【Results】 The positive selection sites (PSSs) of E1E2 and NS3 of common HCV 6a in HLA-DRB1 * 11:01 negative group were greater than those in HLA-DRB1 * 11:01 positive group. Furthermore, the number of PPSs in CD4+T cell peptide in HLA-DRB1 * 11:01 negative group were also greater than those in HLA-DRB1 * 11:01 positive group; Both groups of HCV 6a had a population growth in Guangdong, and the expansion trend of HLA-DRB1 * 11:01 negative group was significantly higher than that of HLA-DRB1 * 11 :01 positive group. Compared to HCV chronic infection group, the response rate of HCV spontaneous clearance group to five peptides (C-52 E2691-707, C-119 NS31545-1560, C-134 NS4A1669-1684, C-154 NS4B1912-1927, C-159 NS4B1929-1944) was higher. However, the HCV chronic infection group showed a higher response rate to two of the peptides(C-111 NS31497-1512, C-130 NS31650-1665). When HLA-DRB1 * 11:01 typing was considered, there was no significant difference in HCV-specific immune response generated by PBMCs between HLA-DRB1 * 11:01 positive and HLA-DRB1 * 11:01 negative groups. 【Conclusion】 This study revealed the relationship between viral selection pressure of HLA-DRB1 * 11:01 HCV infected persons and CD4+T cell antigen epitopes. At the same time, CD4+ T cell antigen epitopes of HCV pan-genotype were obtained, providing basic data for the development of T cell vaccine suitable for HCV pan-genotype.

Study on relationship between platelet transfusion efficacy and KIR-HLA receptor-ligand compatibility / 中国输血杂志

【Objective】 To study the correlation between platelet transfusion efficacy and KIR receptor-HLA ligand. 【Methods】 Thirty-three leukemia patients with positive HLA antibody were tested for cross-matching with donor platelets. Platelets from suitable donors were selected for transfusion, and the 24-hour platelet corrected count increment (CCI) was used to determine the transfusion effect. KIR and ligand genotyping were performed on blood samples from patients and donors by PCR-SSP method, and the relationship between platelet transfusion effects and KIR receptor-HLA ligand was analyzed. 【Results】 In 74 occasions of platelet transfusion, 42 were ineffective and 32 were effective. When the donor had C2 gene and HLA-B Bw4-80T gene, the frequency of ineffective platelet transfusion in the recipient was 69.0% (29/42) and 52.4% (22/35), respectively, which was significantly higher than that in the effective group [25.0% (8/32) and 25.0% (8/32)]. When the donor had C1 gene, and the frequency of effective platelet transfusion in the recipient was 100.0%(32/32), which was higher than that in the ineffective group [83.3%(35/42)]. When the recipient-donor matching mode was KIR2DL1-C2 and KIR3DL1-(HLA-B Bw4-80T), the frequency of ineffective platelet transfusion was 69.0%(29/42) and 40.5%(22/42),higher than that of the effective group [25% (8/32) and 18.8% (6/32)]. When the recipient-donor matching model was KIR2DL3-C1, the rate of effective platelet transfusion in 32 patients (100.0%), which was higher than that (35 patients 83. 3%) in the ineffective group. When the mismatch mode of recipient iKIR+donor HLA ligand receptor was KIR2DL1-C2, the frequency of effective platelet transfusion in the recipient was 78.1% (25/32), which was much higher than that in the ineffective group [31.0% (13/42)]. When the mismatch mode was KIR3DL1-(HLA-B Bw4-80T), the rate of effective platelet transfusion in the recipient was 68.8% (22/32), which was higher than that in the ineffective group (42.9%, 18/42). The difference between the above groups was statistically significant(P<0.05). 【Conclusion】 HLA-C1 and HLA-C2 genes are the key factors affecting the efficacy of platelet transfusion.For platelet refractorines, HLA-C1 is the protective gene, while HLA-C2 and HLA-B Bw4-80T are the susceptible genes. The recipient iKIR+donor HLA ligand receptor model may play an important role in platelet refractoriness.

Study on transfusion-related acute lung injury caused by HLA-Ⅱ antibody / 中国输血杂志

【Objective】 To explore the risk factors of transfusion-related acute lung injury (TRALI). 【Methods】 The clinical symptoms, signs, imaging examinations, and laboratory test results of two patients with TRALI after blood transfusion were retrospectively analyzed, and human leukocyte antigen (HLA) genotyping of the patient and HLA antibodies typing of the plasma donors were performed. 【Results】 The clinical manifestations and laboratory parameters of two patients were consistent with those of TRALI after blood transfusion. After timely clinical respiratory support treatment, all patients were improved. Blood donors produced high titers of HLA-Ⅱ antibodies after pregnancy, including antibodies that specifically recognize the patient′s HLA antigen. 【Conclusion】 Two patients developed TRALI after platelet transfusion from a female blood donor, which was caused by HLA-Ⅱ antibodies.

Factors affecting the efficacy of platelet transfusion and specificity of HLA-Ⅰ antibodies in tumor patients / 中国输血杂志

【Objective】 To analyze the factors affecting the efficacy of platelet transfusion and the specificity of HLA-Ⅰ antibodies in tumor patients. 【Methods】 Tumer patients applied for platelet transfusion from November 2019 to July 2021 in Sichuan Cancer Hospital province were screened for platelet antibodies. The transfusion efficacy was evaluated and its influencing factors were analyzed, Antibody positive patients were detected for HLA-Ⅰ antibodies. 【Results】 The positive rates of platelet antibody and HLA-Ⅰ antibody, as well as the platelet transfusion refractoriness rate were 35.2%(50/142), 32.4%(46/142) and 16.9%(24/142), respectively. The platelet refractoriness rate of platelet antibody positive patients was higher than that of platelet antibody negative patients [30.0%(15/50) vs 9.8%(9/92)] (χ2=9.428, P<0.05). Multivariate logistic results showed that gender (χ2=12.608, P<0.001, OR=3.800, 95%CI: 1.819-7.940) was an independent risk factor for platelet antibody production, and platelet antibody(χ2=8.648, P<0.05, OR=3.952, 95%CI: 1.581~9.878) was the independent risk factor for transfusion efficacy. The detection rates of strong positive, positive and weak positive HLA-I antibodies were 69.6% (32/46), 80.4% (37/46) and 97.8% (45/46), respectively. The antibodies with high detection rate were anti-B*15∶12, anti-B*57∶03, anti-B*57∶01, anti-B*13∶02, anti-B*49∶01, anti-B*50∶01, anti-A*25∶01, anti-B*15∶01, anti-B*15∶02 and anti-B*44∶02. There were 19 kinds of HLA-Ⅰ antibodies with MFI≥10 000, including anti-A*02∶01, anti-A*02∶03 and anti-A*02∶06. The CCI values were lower in HLA-Ⅰ antibody positive patients(n=46) than in HLA-I antibody negative patients(n=96) by Wilcoxon test (P<0.05). 【Conclusion】 Among tumor patients who received platelet transfusion, gender(female) was the risk factor for platelet antibody production. Platelet antibody positive patients were prone to platelet transfusion refractoriness. HLA-Ⅰ antibodies were the main platelet antibodies, suggesting that HLA-Ⅰ gene matching platelets could improve the efficacy of platelet transfusion.

HLA-B 15:13 Positive in an Indonesian Patient with PhenytoinInduced SJS/TEN

@#Steven-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are severe forms of delayed hypersensitivity reaction with an underlying immunologic mechanism involving the interaction between HLA and drug molecules. A-35-year-old Javanese-Indonesian-male, with a history of seizures, presented with skin peeling, mucosal erosions, and purulent eye discharges. He was clinically diagnosed as overlapping SJS/TEN, and both phenytoin and valproic acid became the suspected drugs. Unfortunately, the seizure relapsed and alternative antiepileptic drugs were urgently needed. HLA typing was then performed, revealing the presence of HLA-B*15:13, which has been proven to be correlated with phenytoin adverse reaction by previous study. Thus, phenytoin was totally discontinued and he only prescribed monotherapy valproic acid. Given the high prevalence and common use of phenytoin in clinical practice, HLA evaluation before phenytoin prescription in Indonesia is important. Further studies are recommended to provide more evidence regarding the role of HLA-B*15:13 in phenytoin-induced severe hypersensitivity reactions in Indonesia.