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.

Genetic analysis of a Chinese pedigree with an allele dropout at the HLA-B locus / 中华医学遗传学杂志

OBJECTIVE@#To delineate a deletional mutation of the HLA-B gene in a Chinese pedigree.@*METHODS@#A female patient with acute myeloid leukemia who had visited Liuzhou People's Hospital in April 2022 was selected as the study subject. Routine human leukocyte antigen (HLA) was determined by using PCR-sequence specific oligonucleotide polymorphism (PCR-SSOP) and PCR-sequence-based typing (PCR-SBT) methods. Next generation sequencing (NGS) was used to validate the candidate variant in the HLA-B gene.@*RESULTS@#The PCR-SBT and SSOP results for the HLA-B locus were inconsistent for the patient and her daughter. The SSOP results of the two individuals were HLA-B*35:01, 40:02 and HLA-B*35:01, 40:01, respectively. However, the PCR-SBT results has indicated a mismatch with the nearest HLA-B*35:01 at exon 4. NGS results showed that the HLA-B*35:01 had a 9 bp deletion in the intron 5. The patient's husband was HLA-B*40:01, 58:01, which was normal.@*CONCLUSION@#The variant in intron 5 of the HLA-B gene in this pedigree has mapped to a primer-binding region for the SBT reagent, which has affected the accuracy of PCR-SBT results.

More than two courses of pre-transplant consolidation therapy benefits patients with acute myeloid leukemia in the first complete remission who underwent human leukocyte antigen-matched sibling allografts: a multicenter study / 中华医学杂志(英文版)

BACKGROUND@#Although the need for consolidation chemotherapy after successful induction therapy is well established in patients with acute myeloid leukemia (AML) in first complete remission (CR1), the value of consolidation chemotherapy before allogeneic hematopoietic stem cell transplantation remains controversial.@*METHODS@#We retrospectively compared the effect of the number of pre-transplant consolidation chemotherapies on outcomes of human leukocyte antigen-matched sibling stem cell transplantation (MSDT) for patients with AML in CR1 in multicenters across China. In our study, we analyzed data of 373 AML patients in CR1 from three centers across China.@*RESULTS@#With a median follow-up of 969 days, patients with ≥ 3 courses of consolidation chemotherapy had higher probabilities of leukemia-free survival (LFS) (85.6% vs . 67.0%, P < 0.001) and overall survival (89.2% vs . 78.5%, P  = 0.007), and better cumulative incidences of relapse (10.5% vs . 19.6%, P  = 0.020) and non-relapse mortality (4.2% vs . 14.9%, P  = 0.001) than those with ≤ 2 courses of consolidation chemotherapy. Pre-transplantation minimal residual disease-negative patients with AML in CR1 who received MSDT with ≥ 3 courses of consolidation chemotherapy had a higher probability of LFS (85.9% vs . 67.7%, P  = 0.003) and a lower cumulative incidence of relapse (9.6% vs . 23.3%, P  = 0.013) than those with ≤ 2 courses.@*CONCLUSION@#Our results indicate that patients with AML in CR1 who received MSDT might benefit from pre-transplant consolidation chemotherapy.

The expression of long non-coding RNA human leukocyte antigen complex P5(lncRNA HCP5) in synovial tissue of patients with rheumatoid arthritis is up-regulated and correlated with immune cell infiltration / 细胞与分子免疫学杂志

Objective To identify the potential long non-coding RNA (lncRNA) expressed in rheumatoid arthritis (RA) synovium key to RA onset and investigate its association with immune cell infiltration. Methods RA synovium data were downloaded from the GEO database and normalized. The lncRNAs key to RA onset were identified using multiple machine learning methods. Infiltration of 22 immune cell populations in RA synovium was measured by cell-type identification by estimating relative subsets of RNA transcripts (CIBER-SORT). The relationship between the key lncRNA and infiltrating immune cells was analyzed. Finally, real-time quantitative PCR was applied to validate the expression of the key lncRNA in RA synovial cells. Results lncRNA human leukocyte antigen complex P5(HCP5) was identified as the key lncRNA associated with RA onset. Infiltration analysis revealed increased abundance of CD8+ T cells, γδ T cells, and M1 macrophages while decreased abundance of M2 macrophages in RA synovial tissue. Correlation analysis demonstrated that the lncRNA HCP5 expression was positively associated with the infiltration abundance of CD8+ T cells, γδ T cells, and M1 macrophages in RA synovial tissue. Furthermore,the expression of lncRNA HCP5 in RA synovial cells was up-regulated. Conclusion lncRNA HCP5 expression is up-regulated in RA synovial tissue and potentially associated with immune cells infiltration.

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.

The relevance of a bank with genotyped platelets donors

ABSTRACT Objective: Describe the clinical and laboratory characteristics and the transfusion strategy of patients at Hospital Israelita Albert Einstein with platelet refractoriness and identify their etiological characteristics. Standardize the platelet immunofluorescence technique by flow cytometry as a test for platelet compatibility in immune platelet refractoriness in transfusion support. Methods: Review of medical records of refractory platelet patients followed at HIAE from January 2011 to May 2017. Clinical-demographic data, laboratory data and identification of the use of compatible genotyped platelets for patients in need of transfusion therapy were collected. The analyzed patients were classified according to the etiology of their platelet refractoriness. To standardize the FC-PIFT technique, blood group O platelets were incubated with serum from blood group AB donors and anti-IgG monoclonal antibody to determine the negative control. In order to verify the influence of the ABO system, monoclonal anti-IgG antibodies were incubated with blood group A or B platelets and with blood group O donor serum with isohemagglutinins below and above 1/64. Results: A total of 47 patients were evaluated, a 51% (24/47) preponderance of associated immune and non-immune factors (NIPR + IPR). The most common causes of NIPR + IPR were splenomegaly (54%) and the development of HLA antibodies (88%), consistent with the literature. For patients who required therapeutic transfusion, only a small portion received compatible genotyped platelets. Conclusion: Although 60% of patients could benefit from the therapeutic transfusion of genotyped platelets, only 10% were actually transfused with this type of blood component. This reaffirms the need for investments in a bank of genotyped platelet donors.

Platelet antibodies identification: comparison between two laboratory tests

ABSTRACT Introduction: Platelet antibody identification is indispensable for diagnosing the human platelet antigen (HPA) or human leukocyte antigen (HLA) immunization, mostly because it can restrict the compatibility and results of transfusions. Correct detection of these antibodies is of utmost importance for the diagnosis and treatment. Method: We present 16 platelet alloimmunization results, comparing two tests with different technologies: the MAIPA (monoclonal antibody immobilization of platelet antigens), as a reference technique, and a bead-based assay, the Pak-Lx. Results: Eleven samples (68.75%) showed agreement in both techniques. Two tests were false negatives in the Pak-Lx: a pan-reactivity in GPIIbIIIa and an anti-HPA-9b. On the other hand, the Pak-Lx was more sensitive to detect a decreasing anti-HPA-5b. The Pak-Lx found an anti-HPA-2b positive, but with a low median fluorescent intensity (MFI), suggesting a false-positive result. Moreover, in one case, the MAIPA was negative for a positive Pak-Lx HLA. Conclusion: Antibody platelet diagnosis can sometimes be challenging. The methods seemed similar, the Pak-Lx being faster and simpler than the MAIPA, and they can be complementary to solve clinical issues.

Aspectos técnicos y clínicos de la prueba cruzada de histocompatibilidad en el trasplante de órganos solidos / Technical and clinical aspects of the histocompatibility crossmatch assay in solid organ transplantation

La presencia de anticuerpos dirigidos contra los antígenos leucocitarios humanos (Human Leukocyte Antigens, HLA) que se expresan en las células del donante, es uno de los factores de riesgo más importantes asociados con las complicaciones clínicas después del trasplante. La prueba cruzada es una de las pruebas de histocompatibilidad más eficaces para la detección de anticuerpos específicos contra el donante en los receptores de injertos. En los primeros métodos de la prueba cruzada, se utilizaba la citotoxicidad dependiente del complemento, que es útil para detectar dichos anticuerpos responsables del rechazo hiperagudo del injerto, pero carece de la sensibilidad adecuada. Por ello, se desarrollaron métodos de pruebas cruzadas más sensibles, entre ellas, la prueba cruzada por citometría de flujo que hoy se considera el método preferido. En este artículo se revisa la evolución de la prueba cruzada y los factores más importantes que deben tenerse en cuenta al realizarla y al interpretar los resultados de esta prueba fundamental para la supervivencia a largo plazo del injerto.

The presence of antibodies directed against human leukocyte antigens (HLA) expressed on donor cells is a significant risk factor for serious clinical complications after transplantation. The crossmatch assay is one of the most important tests available for the detection of donor-specific antibodies in potential allograft recipients. Early crossmatch methods utilized complement-dependent cytotoxicity, which is useful for detecting the donor-specific anti- HLA antibodies responsible for hyperacute allograft rejection but lacks adequate sensitivity. Consequently, more sensitive crossmatch methods have been developed, ultimately leading to the flow cytometry crossmatch as the currently preferred methodology. Herein, we review the evolution of the crossmatch assay and the most important factors to consider when performing and interpreting the results of this fundamental assay for ensuring the long-term survival of the transplanted organ.

Síndrome DRESS inducido por ácido valproico en una niña que respondió a la ciclosporina con análisis de HLA / Valproic acid-induced DRESS in a child responding to cyclosporine with HLA analysis

El síndrome de erupción medicamentosa con eosinofilia y síntomas sistémicos (drug reaction with eosinophilia and systemic symptoms, DRESS), también conocido como síndrome de hipersensibilidad inducida por medicamentos, es una reacción rara potencialmente mortal que causa una erupción grave y que puede provocar insuficiencia multiorgánica. Como con otras erupciones medicamentosas graves, los linfocitos T específicos para un medicamento tienen una función crucial en el síndrome DRESS. El modelo de hapteno/pro-hapteno, el modelo de interacción farmacológica y el modelo alterado de repertorio de péptidos son tres modelos diferentes desarrollados para describir la relación/interacción entre un medicamento o sus metabolitos y el sistema inmunitario. Analizamos nuestra experiencia con el tratamiento con ciclosporina en un caso de síndrome DRESS resistente a esteroides causado por ácido valproico en una niña y sus resultados clínicos, de laboratorio y de antígeno leucocitario humano (HLA).

Drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug-induced hypersensitivity syndrome, is a potentially life-threatening rare reaction that causes a severe rash and can lead to multiorgan failure. As in other severe drug eruptions, drug-specific T lymphocytes play a crucial role in DRESS. The hapten/pro-hapten model, pharmacological interaction model, and altered peptide repertoire model are three different models developed to describe the relationship/interaction between a medication or its metabolites and the immune system. We discuss our experience with cyclosporine treatment in a steroid-resistant DRESS syndrome caused by valproic acid in a girl, as well as her clinical, laboratory, and human leukocyte antigens (HLA) study results

A retrospective comparative study of haplotype hematopoietic stem cell transplantation and human leukocyte antigen-matched sibling donor hematopoietic stem cell transplantation in the treatment of acute B-lymphocyte leukemia / 中华血液学杂志

Objective: To investigate whether haplotype hematopoietic stem cell transplantation (haplo-HSCT) is effective in the treatment of pre transplant minimal residual disease (Pre-MRD) positive acute B lymphoblastic leukemia (B-ALL) compared with HLA- matched sibling donor transplantation (MSDT) . Methods: A total of 998 patients with B-ALL in complete remission pre-HSCT who either received haplo-HSCT (n=788) or underwent MSDT (n=210) were retrospectively analyzed. The pre-transplantation leukemia burden was evaluated according to Pre-MRD determinedusing multiparameter flow cytometry (MFC) . Results: Of these patients, 997 (99.9% ) achieved sustained, full donor chimerism. The 100-day cumulative incidences of neutrophil engraftment, platelet engraftment, and grades Ⅱ-Ⅳ acute graft-versus-host disease (GVHD) were 99.9% (997/998) , 95.3% (951/998) , and 26.6% (95% CI 23.8% -29.4% ) , respectively. The 3-year cumulative incidence of total chronic GVHD was 49.1% (95% CI 45.7% -52.4% ) . The 3-year cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) of the 998 cases were 17.3% (95% CI 15.0% -19.7% ) and 13.8% (95% CI 11.6% -16.0% ) , respectively. The 3-year probabilities of leukemia-free survival (LFS) and overall survival (OS) were 69.1% (95% CI 66.1% -72.1% ) and 73.0% (95% CI 70.2% -75.8% ) , respectively. In the total patient group, cases with positive Pre-MRD (n=282) experienced significantly higher CIR than that of subjects with negative Pre-MRD [n=716, 31.6% (95% CI 25.8% -37.5% ) vs 14.3% (95% CI 11.4% -17.2% ) , P<0.001]. For patients in the positive Pre-MRD subgroup, cases treated with haplo-HSCT (n=219) had a lower 3-year CIR than that of cases who underwent MSDT [n=63, 27.2% (95% CI 21.0% -33.4% ) vs 47.0% (95% CI 33.8% -60.2% ) , P=0.002]. The total 998 cases were classified as five subgroups, including cases with negative Pre-MRD group (n=716) , cases with Pre-MRD<0.01% group (n=46) , cases with Pre-MRD 0.01% -<0.1% group (n=117) , cases with Pre-MRD 0.1% -<1% group (n=87) , and cases with Pre-MRD≥1% group (n=32) . For subjects in the Pre-MRD<0.01% group, haplo-HSCT (n=40) had a lower CIR than that of MSDT [n=6, 10.0% (95% CI 0.4% -19.6% ) vs 32.3% (95% CI 0% -69.9% ) , P=0.017]. For patients in the Pre-MRD 0.01% -<0.1% group, haplo-HSCT (n=81) also had a lower 3-year CIR than that of MSDT [n=36, 20.4% (95% CI 10.4% -30.4% ) vs 47.0% (95% CI 29.2% -64.8% ) , P=0.004]. In the other three subgroups, the 3-year CIR was comparable between patients who underwent haplo-HSCT and those received MSDT. A subgroup analysis of patients with Pre-MRD<0.1% (n=163) was performed, the results showed that cases received haplo-HSCT (n=121) experienced lower 3-year CIR [16.0% (95% CI 9.4% -22.7% ) vs 40.5% (95% CI 25.2% -55.8% ) , P<0.001], better 3-year LFS [78.2% (95% CI 70.6% -85.8% ) vs 47.6% (95% CI 32.2% -63.0% ) , P<0.001] and OS [80.5% (95% CI 73.1% -87.9% ) vs 54.6% (95% CI 39.2% -70.0% ) , P<0.001] than those of MSDT (n=42) , but comparable in 3-year NRM [5.8% (95% CI 1.6% -10.0% ) vs 11.9% (95% CI 2.0% -21.8% ) , P=0.188]. Multivariate analysis showed that haplo-HSCT was associated with lower CIR (HR=0.248, 95% CI 0.131-0.472, P<0.001) , and superior LFS (HR=0.275, 95% CI 0.157-0.483, P<0.001) and OS (HR=0.286, 95% CI 0.159-0.513, P<0.001) . Conclusion: Haplo HSCT has a survival advantage over MSDT in the treatment of B-ALL patients with pre MRD<0.1% .