Heart transplant candidates that are highly sensitized against human leukocyte antigens (HLA) face ongoing challenge in finding immunologically compatible donors. Desensitization strategies aimed at reducing HLA antibody...Heart transplant candidates that are highly sensitized against human leukocyte antigens (HLA) face ongoing challenge in finding immunologically compatible donors. Desensitization strategies aimed at reducing HLA antibody titers have variable success rates. Imlifidase, a novel immunoglobulin G-degrading enzyme derived from Streptococcus pyogenes has been successfully used to eliminate pre-formed antibodies in sensitized kidney transplant recipients. We present the first case of imlifidase use for depleting antibodies in a highly and broadly sensitized heart/liver transplant candidate allowing for transplantation to proceed. Overall, our case demonstrates the feasibility of imlifidase use for the purpose of opening a donor-specific antibody-free window to transplantation in patients who are otherwise not transplantable, due strong sensitization refractory to conventional desensitization approaches.
Current approaches used for pediatric liver transplant (LT) surveillance have diagnostic limitations. We used pleximmune™ immune reactivity index (IRI) and anti-HLA donor specific antibody (DSA) to predict the adequacy o...Current approaches used for pediatric liver transplant (LT) surveillance have diagnostic limitations. We used pleximmune™ immune reactivity index (IRI) and anti-HLA donor specific antibody (DSA) to predict the adequacy of immunosuppression (IS) relative to risk of acute cellular rejection (ACR) at 1-year post LT. This is a retrospective chart review of children who underwent LT between January 1, 2016, through December 31, 2020, and had at least one pleximmune measurement performed within 60-days of a liver biopsy. There were 45 liver biopsies with accompanying pleximmune in 31 children. An inverse correlation was observed between tacrolimus level and IRI (R = -0.34; p = 0.039). The sensitivity, specificity, positive and negative predictive values of IRI for diagnosis of ACR was 55 %, 65 %, 33 % and 81 % respectively. The combination of DSA and IRI had a specificity of 92 % and negative predictive value of 89 % for ACR. In conclusion, a high IRI identifies recipients with low tacrolimus levels. Thus, the associations observed in this non-standardized cohort support the use of pleximmune IRI in combination with DSA, for hypothesis generation in future studies involving post liver transplant graft immune surveillance.
Transfusion support for sensitized patients is an important function of blood centers and HLA laboratories. However, access to widely available software to facilitate matching patients with compatible donor units is limi...Transfusion support for sensitized patients is an important function of blood centers and HLA laboratories. However, access to widely available software to facilitate matching patients with compatible donor units is limited. We developed vendor-supported and integrated software that interfaces with the laboratory informatics system, sourcing typing data from our platelet donor registry and retrieving patient HLA typing and unacceptable antibody specificities. The application filters antigen-negative donors and ranks them using an algorithm that incorporates HLA match, donor homozygosity, and cross-reactive group comparison for mismatched antigens, and generates a customizable report of ranked donors for the blood center. Low, moderate, and high antibody reactivities can be filtered to better support highly sensitized patients. Implementing vendor-supported software ensures continued maintenance, support, and the opportunity for updates with evolving platelet matching protocols. This customizable solution reduces transcription errors and streamlines data retrieval, allowing provision of timely and efficient transfusion support for patients.
Single Antigen Bead (SAB) assays are the cornerstone of HLA antibody detection in transplant immunology. However, discrepancies in mean/median fluorescence intensity (MFI) values between the two commercially available as...Single Antigen Bead (SAB) assays are the cornerstone of HLA antibody detection in transplant immunology. However, discrepancies in mean/median fluorescence intensity (MFI) values between the two commercially available assays raise concerns about result interpretation and assay interoperability. Using 281 well-characterized serum samples positive for a broad range of HLA antibodies, we evaluated 118 core HLA antibody specificities for MFI concordance across platforms. Cell-binding ability of specific HLA antibodies was evaluated by T- and B-cell flow cytometric crossmatch (FCXM) in 613 single antibody-targeted pairings. Strong correlations were observed for HLA-A, -B, and -DR antibodies between platforms. Correlations for HLA-C, -DQ and -DP were moderate to poor. Discordance often linked to differences in allele composition-particularly for DQ and DP, which use distinct α/β chain pairings. FCXM correlated well with MFI for Class I antibodies, but correlation was limited for Class II antibodies. Despite design differences, the assays were largely concordant for most HLA specificities. Used together, they offer complementary insights, particularly for challenging loci such as HLA-C, -DQ, and -DP. However, for antibody profiling in transplant candidates, the lack of correlation for the latter loci could make accurate data interpretation difficult if the bead sets and vendor kits were used interchangeably.
Non-syndromic hearing loss (NSHL) is a common sensory disorder with a multifactorial origin, involving both genetic and environmental components. Its genetic basis shows significant variability and incomplete penetrance...Non-syndromic hearing loss (NSHL) is a common sensory disorder with a multifactorial origin, involving both genetic and environmental components. Its genetic basis shows significant variability and incomplete penetrance across populations. Environmental factors, especially TORCH infections and sterile inflammation, may contribute to NSHL by triggering inflammatory cascades. Cytokines, secreted proteins crucial in immune regulation, play a central role in mediating these inflammatory responses. This study investigates whether genetic variants in cytokine genes contribute to NSHL susceptibility. A case-control genetic association study was conducted in the Malayalam-speaking Dravidian population, focusing on both pro- and anti-inflammatory cytokine gene variants. The findings reveal, for the first time, a strong association between NSHL and variants in pro-inflammatory cytokines IL1A, IFNG, IL3, and IL12B, along with the anti-inflammatory cytokine IL4. These risk variants were associated with increased pro-inflammatory activity and reduced anti-inflammatory responses. Interactome analysis showed interactions among cytokine genes IL6, IL1B, and TNF with key candidate genes such as GSDME, DIABLO, and GJA1. The results suggest an alternative NSHL pathogenesis mechanism, where environmental influences may act through cytokine gene variants to affect gene expression, possibly via a "Goldilocks effect." This study underscores the complex interplay of genetic and environmental factors in NSHL development.
Fujioka M, Itonaga H, Sawayama Y
… +11 more, Aibara N, Kojima A, Kirino Y, Watanabe H, Yamada Y, Sakamoto H, Taguchi M, Kato T, Horai M, Ohyama K, Miyazaki Y
Chronic graft-versus-host disease (cGVHD) is an alloimmune disease characterized by inflammation, immune dysregulation, and pathogenic fibrosis after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Donor-...Chronic graft-versus-host disease (cGVHD) is an alloimmune disease characterized by inflammation, immune dysregulation, and pathogenic fibrosis after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Donor-derived B cells have a significant role of cGVHD development; however, the proteins targeted by B cell-mediated cGVHD remain unclear. To identify cGVHD-associated antigens, we investigated immune complexes (ICs) in the serum of patients who underwent allo-HSCT. Of the 26 patients examined, 17 developed cGVHD, and the 1-year cumulative incidence of cGVHD was 57.7%. A comprehensive analysis of ICs identified 89 distinct IC-associated antigen candidates, including significantly enriched clusters associated with "regulation of secretion by cell", "regulation of protein kinase activity", "positive regulation of organelle organization", and "positive regulation of synaptic transmission". Regarding overlap between the tissue specificity of proteins and cGVHD-affected organs, ten proteins were identified as organ-specific antigen candidates. In summary, the immune complexome analysis identified antigen candidates in patients with cGVHD, suggesting that the heterogeneity of target proteins might lead to, at least in a part, diverse clinical manifestations of cGVHD. The results of this study provide important insights into immune dysregulation in cGVHD.
BACKGROUND/OBJECTIVES: Chemokines and their receptors are key mediators of inflammation and immune cell migration in atherosclerosis and coronary artery disease (CAD). This study examines the association of MCP-1-2518A/G...BACKGROUND/OBJECTIVES: Chemokines and their receptors are key mediators of inflammation and immune cell migration in atherosclerosis and coronary artery disease (CAD). This study examines the association of MCP-1-2518A/G (rs1024611), MCP-1-362G/C (rs2857656), and CCR2-V64I (rs1799864) polymorphisms with CAD susceptibility and severity in a Tunisian population. METHODS: A total of 302 participants were included: 200 CAD patients and 102 healthy controls matched by age and sex. CAD was confirmed by coronary angiography, and severity assessed via the Gensini score. Genotyping was performed using PCR and RFLP analysis. RESULTS: The MCP-1-2518G allele was significantly associated with increased CAD risk (p = 0.02; OR = 1.49 (1.09-2.48)), with stronger effects under the dominant model and after adjustment for confounders. This association was more pronounced in patients with myocardial infarction, obesity, and dyslipidemia. In contrast, the CCR2-V64I variant was associated with reduced CAD severity (p = 0.011; RD = 2.48 (2.01 to -2.95)), particularly in individuals without smoking habit, obesity, or dyslipidemia. CONCLUSION: MCP-1-2518A/G and CCR2-V64I polymorphisms may serve as genetic markers for CAD susceptibility and severity, offering potential for improved risk stratification and personalized therapeutic approaches.
Solid-phase immunoassays (SPIs) are the current standard of care for detecting and identifying anti-HLA antibodies in transplantation. However, whether SPIs with different configurations provide comprehensive antigen and...Solid-phase immunoassays (SPIs) are the current standard of care for detecting and identifying anti-HLA antibodies in transplantation. However, whether SPIs with different configurations provide comprehensive antigen and eplet coverage has not been documented in the literature. We systematically compared four commercial SPI panels - Mixed, PRA (Panel Reactive Antibody), SAB (Single Antigen Bead), and ExPlex - to assess their coverage of antigens and eplets cataloged in the HLA Eplet Registry. Our results show overlapping and variable antigen and eplet representation across these assays. Out of a total of 252 class I and 260 class II eplets in the HLA Eplet Registry, 251 (99.6 %) and 260 (100 %) were covered by one or more assays; 209 (82.9 %) class I and 189 (72.7 %) of class II eplets were covered by all four assays. All antibody-verified eplets in Class I antigens are represented in three or more assays, whereas two Class II eplets were exclusive to SAB. Although ExPlex did not significantly increase the number of eplets represented beyond the SAB panel, it expanded the diversity of eplets within unique antigenic contexts. We also examined the relationship between eplet dose per bead and antibody reactivity in the PRA assay. Positive correlations were observed between bead-level eplet numbers and mean fluorescence intensity (MFI) in a collection of sera with 82LR (Bw4) or 80 N (Bw6) eplet patterns. Our findings indicate broad coverage of HLA eplets by current SPIs, which offer acceptable antigenic coverage for pre-transplant immune risk screening. We also share the R script to enable ongoing analyses and monitoring of antigen and eplet coverage in future screening reagents.
BACKGROUND: Treatment failure in triple-negative breast cancer (TNBC) primarily stems from chemotherapy resistance. Doxorubicin (DOX) is a commonly used therapeutic agent for TNBC; however, the role and mechanisms of imm...BACKGROUND: Treatment failure in triple-negative breast cancer (TNBC) primarily stems from chemotherapy resistance. Doxorubicin (DOX) is a commonly used therapeutic agent for TNBC; however, the role and mechanisms of immune regulation in DOX resistance remain unclear. METHODS: In this study, we analyzed single-cell data from public databases comparing DOX-resistant and sensitive TNBC patients, focusing on cell subpopulations, enriched pathways, and cell communication. We then explored the expression of glutathione peroxidase 1 (Gpx1) in macrophages and its impact on their polarization. Subsequently, we established co-culture systems of M0 macrophages and DOX-resistant TNBC cells to elucidate the specific effects of Gpx1-induced M2 polarization on the cancerous characteristics of TNBC. A xenograft nude mouse model was constructed to investigate the effect of Gpx1 expression on the sensitivity of TNBC to DOX. RESULTS: Our findings indicated a significant increase in macrophage proportion within TNBC DOX patient samples, with high expression of Gpx1 in the Macrophage_Gpx1+ cells of the DOX-resistant group. Enrichment analysis revealed that Gpx1 was primarily associated with immune response-related pathways, and strong interactions between Macrophage_Gpx1+ cells and other immune cells were observed. In vitro experiments confirmed that Gpx1 induced M2 polarization of macrophages, enhancing the proliferation, migration, and invasion capabilities of DOX-resistant TNBC cells. Animal experiments revealed that knocking down Gpx1 suppressed macrophage M2 polarization and enhanced the sensitivity of TNBC to DOX. CONCLUSION: This study unveiled a novel avenue for immune regulation in TNBC during DOX treatment. Inhibiting Gpx1 expression to prevent macrophage polarization towards the M2 phenotype may enhance the sensitivity of TNBC to DOX.
BACKGROUND: The clinical link between psoriasis (PsO) and cardiovascular diseases (CVDs) is well-established, yet the genetic underpinnings of their comorbidity remain unclear. This study aimed to systematically map the...BACKGROUND: The clinical link between psoriasis (PsO) and cardiovascular diseases (CVDs) is well-established, yet the genetic underpinnings of their comorbidity remain unclear. This study aimed to systematically map the shared genetic architecture between PsO and CVDs to identify key risk loci, effector genes, and biological pathways. METHODS: We analyzed large-scale genome-wide association study data for PsO and 11 CVDs to assess their genetic correlation. We then identified pleiotropic loci-variants associated with both PsO and CVDs-and applied colocalization analysis to test whether a single causal variant at each locus could explain the shared association. To interpret these findings, we performed functional annotation to map variants to genes and conducted heritability enrichment analysis to identify critical tissues. Finally, we performed an immune-specific colocalization analysis to investigate the role of distinct immune cell types in driving the shared disease risk. RESULTS: The findings revealed significant shared genetic risk between PsO and seven major CVDs (e.g., hypertension, myocardial infarction, and coronary artery disease). We identified 58 pleiotropic loci at the level of genome-wide significance (P < 5 × 10). Of these, 11 loci passed causal colocalization tests, indicating a high probability of a shared causal variant. Gene-level analysis pinpointed 97 candidate genes, and through multi-evidence integration, we prioritized four (SLC22A5, LMAN2, HSD3B7, and ZNF668) as high-confidence therapeutic targets. Enrichment analyses showed these shared genes are highly expressed in blood and immune-related tissues and are involved in key pathways such as immune activation and cytokine signaling. Furthermore, our findings suggest that T-cell-mediated immune dysregulation is a key mechanism underlying the comorbidity of PsO and at least five of the studied CVDs. CONCLUSION: Our systematic genetic analysis identifies shared loci and candidate genes for psoriasis and several cardiovascular diseases. The findings point toward immune-mediated pathways as potential links between these conditions and provide a prioritized list of targets warranting future functional study and therapeutic evaluation.
HLA compatibility between patients and donors is a determining factor for the success of stem cell and solid organ transplantations. However, finding suitable donors remains challenging due to the highly polymorphic natu...HLA compatibility between patients and donors is a determining factor for the success of stem cell and solid organ transplantations. However, finding suitable donors remains challenging due to the highly polymorphic nature of HLA genes. Here we are describing 16 novel HLA-A, -B, -C and -DRB1 alleles identified over the period of 2 years. Fourteen differed from their closest reference allele sequence by single nucleotide substitutions detected in the coding regions and 13 contained polymorphism outside antigen recognition domains (exons 2 and 3 in class I and exon 2 in HLA class II). Two novel alleles, a non-sense substitution and a deletion of 2 bp resulted in two null alleles, while a substitution in a splice site resulted in an allele with questionable expression status. In HLA matching procedures, particularly in donor selection, it is important to determine alternatively expressed HLA alleles. Thirteen additional HLA-A, -B, -C and -DRB1 alleles detected as novel at the time of testing were already reported by other laboratories by the time of submission.
To study the impact of exosomes from Systemic lupus erythematosus (SLE) individuals on the production of inflammatory cytokines in dendritic cells (DCs) and the underlying mechanism. We extracted exosomes from SLE patien...To study the impact of exosomes from Systemic lupus erythematosus (SLE) individuals on the production of inflammatory cytokines in dendritic cells (DCs) and the underlying mechanism. We extracted exosomes from SLE patients (SLE-exo) and healthy adults (HCs-exo), then we treated exosomes by ultrasound to confirm whether the release of exosomal contents can affect the function of exosomes, finally we treated DCs with the exosomes. According to the ELISA results, comparing to control group, the release of IL-10, IL-6, IL-1β, and IL-12 was elevated by HCs-exo, while the release of IL-10, IL-6, IL-1β, IL-12 and TNF-α was markedly elevated by SLE-exo. And the increased release of cytokines was accompanied by the upregulation of p-P70S6K, p-mTOR, and p-4EBP1. Moreover, compared to SLE-exo-treated DCs, the release of IL-6, IL-12 and TNF-α was repressed by the co-administration of rapamycin, especially the release of IL-6, and the level of p-P70S6K, p-mTOR and p-4EBP1 also was repressed. The qPCR results of exosomes showed that miR-223 was upregulated while miR-25 and miR-let-7a were downregulated in SLE-exo. Even though there are some limitations in our research, but based on these results, we considered that the exosomes from SLE patients may promote the production of inflammatory cytokines in mo-DCs by regulating mTOR signaling.
BACKGROUND: There is an increasing number of biopsies with histological features of antibody mediated rejection but lacking the detection of anti-human leucocyte antigen (HLA) antibodies or C4d deposition. Anti-Human neu...BACKGROUND: There is an increasing number of biopsies with histological features of antibody mediated rejection but lacking the detection of anti-human leucocyte antigen (HLA) antibodies or C4d deposition. Anti-Human neutrophil antigens-3 (HNA-3) have been reported in severe and fatal cases of Transfusion-Related Acute Lung Injury and Neutropenia Alloimmune Neonatal, a phenomenon mediated by antibody endothelial activation. This study investigated the association between the presence of pre-formed anti-HNA-3 antibodies and the development of a recurrent episode of acute rejection (AR) after kidney transplantation. METHODS: Patients who experienced the first biopsy confirmed acute rejection (BCAR) between 2011-2019 were screened for the presence of anti-HNA-3 antibodies using pretransplant serum samples. Three techniques were used, Granulocyte Agglutination Test (GAT), Granulocyte Immunofluorescence Test (Flow-GIFT), and microsphere-based technique (LABSCreen Multi kit, One Lambda) to detect and determine the specificity of the antibodies. HNA-3 genotyping of recipients and donors was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A matched control group included patients with first BCAR but without pretransplant anti-HNA-3 antibodies. RESULTS: Of 1256 patients with first BCAR, 33 (2.6 %) had anti-HNA-3 antibodies. Compared to the matched control, survival-free of a second BCAR was lower in patients with any anti-HNA-3 antibody (p = 0.014) and in patients with donor specific anti-HNA-3 antibodies (p = 0.015). No differences were observed in histological phenotypes of the rejection episodes comparing patients with and without anti-HNA-3 antibodies. CONCLUSIONS: This matched cohort study suggests that preformed anti-HNA-3 antibodies are associated with an increased risk of recurrent BCAR. The involved mechanisms remain to be elucidated.
Diverse human leukocyte antigens (HLA) play a crucial role in adaptive immune responses via peptide presentation. Unrelated to this role, alloimmunization to mismatched HLA represents a significant barrier to allogeneic...Diverse human leukocyte antigens (HLA) play a crucial role in adaptive immune responses via peptide presentation. Unrelated to this role, alloimmunization to mismatched HLA represents a significant barrier to allogeneic transplantation. Despite the complexity of HLA structures and the diversity of alleles, advancements in recombinant HLA protein production have enabled their use in diagnostics and are paving the way for therapeutic applications. HLA-Fc fusion proteins, combining the extracellular domains of HLA molecules with the Fc region of immunoglobulins, offer a promising approach for antigen-specific immunotherapy. This review examines the engineering challenges and therapeutic potential of HLA-Fc fusion proteins in mitigating unwanted HLA alloimmunization and antibody-mediated rejection (AMR) following transplantation. HLA-Fc fusion proteins provide enhanced stability and effector functions, enabling the selective targeting and depletion of anti-HLA antibody-producing cells. Preclinical studies demonstrate their efficacy in neutralizing anti-HLA antibodies and depleting cognate antibody-producing cells, highlighting their potential to improve transplant outcomes and reduce AMR. Future research may focus on optimizing these fusion proteins, understanding their effects on primary B cells and long-lived plasma cells, and exploring combination therapies to enhance their clinical efficacy.
Human metapneumovirus (HMPV) is a leading cause of acute respiratory tract infections, particularly in pediatric, elderly, and immunocompromised populations. Despite its clinical significance, no licensed vaccine is curr...Human metapneumovirus (HMPV) is a leading cause of acute respiratory tract infections, particularly in pediatric, elderly, and immunocompromised populations. Despite its clinical significance, no licensed vaccine is currently available for HMPV. This study employed an in silico immunoinformatics-based approach to design a multi-epitope subunit vaccine candidate targeting key structural proteins of HMPV, including Matrix2-2, Matrix2-1, Matrix, and Phosphoprotein. B-cell and T-cell epitopes were systematically predicted and screened based on their immunogenicity, antigenicity, non-toxicity, and non-allergenicity. The most promising epitopes were assembled into a single construct using appropriate peptide linkers and immunostimulatory adjuvants to enhance host immune activation. Molecular docking and molecular dynamics (MD) simulations were performed to evaluate the structural stability and binding affinity of the vaccine construct with toll-like receptors TLR4, supporting its potential to trigger innate immune pathways. Additional computational analyses, including immune simulation and in silico cloning, were conducted to further assess the vaccine's immunogenic profile and expression feasibility. These findings suggest that the proposed multi-epitope vaccine candidate may offer a viable strategy for HMPV prevention and warrants further experimental validation and preclinical evaluation.
Yeung Wong ET, Balshaw R, Gibson IW
… +11 more, Ho J, Shaw J, Karpinski M, Trachtenberg A, Pochinco D, Goldberg A, Birk P, Pinsk M, Rush DN, Nickerson PW, Wiebe C
Immunosuppressive treatment is used in transplant patient management and chronic autoimmune disorders. Personalization of immunosuppression and effective management of side effects requires close monitoring of the patien...Immunosuppressive treatment is used in transplant patient management and chronic autoimmune disorders. Personalization of immunosuppression and effective management of side effects requires close monitoring of the patient's health and immune system function. An emerging immune status biomarker is torque teno virus (TTV), a non-pathogenic virus highly prevalent across different populations and age groups. Multiple studies associate rising TTV levels with increased immunosuppression. Our new qPCR test is developed to reliably quantify TTV in human blood samples. Analytical study demonstrated consistent accuracy and precision of the new assay in detecting and measuring DNA sequences from 27 most common TTV species within a range from single copy to 200 million copies of DNA per reaction. Specificity of qPCR was confirmed by negative results of the assay when tested with up to 700 ng of human genomic DNA per reaction, and in presence of up to 10 million copies of other anelloviruses. Blood samples from 80 healthy volunteers tested by the new qPCR assay demonstrated detectable levels of TTV in 80 % donors. Accuracy of qPCR data for blood samples collected in Acid Citrate Dextrose and EDTA tubes was confirmed by a strong correlation (R > 0.95) to digital PCR results.
Sera from patients with previous transplants, transfusions, and pregnancies may contain multiple Human Leukocyte Antigen (HLA)-specific antibodies recognizing various functional epitopes or eplets. The identification and...Sera from patients with previous transplants, transfusions, and pregnancies may contain multiple Human Leukocyte Antigen (HLA)-specific antibodies recognizing various functional epitopes or eplets. The identification and verification of eplets in these high Panel Reactive Antibody (PRA) cases are important for understanding HLA antigenicity and potentially improving transplantation outcomes. For a particular high PRA case, we utilized adsorption and elution techniques using cells and HLA-specific magnetic beads to identify and verify eplets. The resulting eluates confirmed seven established eplet patterns while also uncovering two novel binding patterns against A*01:01 and B*53:01. The isolation of the HLA-specific antibodies allows us to perform competition assays against monoclonal antibodies to confirm the epitope specificity. Using available HLA crystal structures, we proposed that the physicochemical properties of residues 163 and 167 are crucial for the binding of the A*01:01-targeted antibody identified in this study, as well as another A*01:01-targeted antibody previously discovered by Lima et al. [1]. Our studies demonstrate that isolating antibodies and analyzing the physicochemical properties of the eplet will lead to a more comprehensive understanding of HLA immunogenicity.
Wong ETY, Balshaw R, Gibson IW
… +11 more, Ho J, Shaw J, Karpinski M, Trachtenberg A, Pochinco D, Goldberg A, Birk P, Pinsk M, Rush DN, Nickerson PW, Wiebe C
HLA-DQ mismatch has been correlated with worse kidney allograft outcomes. However, there is linkage disequilibrium between HLA-DQ and HLA-DR, and the independent effect of HLA-DQ mismatches, particularly HLA-DQαβ heterod...HLA-DQ mismatch has been correlated with worse kidney allograft outcomes. However, there is linkage disequilibrium between HLA-DQ and HLA-DR, and the independent effect of HLA-DQ mismatches, particularly HLA-DQαβ heterodimer mismatches, on allograft outcomes after adjustment for HLA-DR mismatches has been understudied. It is also unknown whether the potential for HLA-DQ molecules to form cis- or trans-heterodimers impacts allograft outcomes. We analyzed 866 well-characterized kidney transplant recipients for the relevance of potential cis/trans-HLA-DQ⍺β heterodimers on T cell-mediated rejection, antibody-mediated rejection, death-censored allograft survival, and all-cause allograft survival. We found that including potential HLA-DQ⍺β cis/trans-heterodimer mismatches did not improve prediction models for all outcomes compared to HLA-DQ⍺β cis-heterodimers alone. We also studied the independent effect of HLA-DQ⍺β mismatch on these outcomes after adjusting for HLA-DR mismatch in multivariate models. Both HLA-DR antigen and HLA-DQ⍺β cis-heterodimer mismatch were univariate but not multivariate correlates of these outcomes when adjusted for each other. Collinearity between HLA-DRB1, HLA-DQB1, and HLA-DQA1 alleles, and the dilution of survival outcomes with non-alloimmune related events are potential reasons. This underlies the need for novel approaches to precision in alloimmune risk assessment, e.g., molecular mismatch, for use in prediction models and allocation algorithms.
Malaria, a potentially fatal disease caused by various Plasmodium species, continues to be a significant global health burden, with Plasmodium falciparum responsible for over 90% of malaria mortality worldwide (Snow, 201...Malaria, a potentially fatal disease caused by various Plasmodium species, continues to be a significant global health burden, with Plasmodium falciparum responsible for over 90% of malaria mortality worldwide (Snow, 2015). Current treatments, primarily relying on chemotherapy, face challenges due to drug resistance and severe side effects, highlighting the need for more effective and sustainable solutions. Vaccine-based approaches offer a promising alternative, providing potential long-term immunity with reduced risk of resistance. This study aims to develop a robust multi-epitope vaccine targeting four key Plasmodium falciparum 3D7 proteins: PfPHB1, PfPHB2, PfHSP70, and PfGARP. These proteins were selected based on their crucial roles in the parasite's survival and pathogenicity, as well as their conserved sequences present during the blood stage of infection. Using an array of bioinformatics tools, we identified B cell epitopes, HTL epitopes, and CTL epitopes, ensuring their antigenicity, non-toxicity, and non-allergenicity. These epitopes were then assembled into a vaccine construct, enhanced with the FliC protein of Salmonella typhimurium as an adjuvant to boost the immune response. The vaccine construct's secondary and tertiary structures were predicted and refined using PSIPRED and AlphaFold2, respectively. Molecular docking studies demonstrated strong interactions between the vaccine and TLR5, indicating potential efficacy in inducing an immune response. Codon optimization and in silico cloning in Escherichia coli K12 ensured efficient expression of the vaccine construct. Immune simulation using the C-ImmSim server predicted a robust and comprehensive immune response, further validating the vaccine's potential. This in-silico study represents a significant step towards developing a multi-epitope vaccine for malaria, addressing the limitations of current treatments and paving the way for experimental validation and future clinical trials.