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Journal of Immunological Methods Feb 2022Antibody-mediated rejection is a major cause of graft failure in organ transplantation. For this reason, B cell responses are of particular interest to transplantation...
Antibody-mediated rejection is a major cause of graft failure in organ transplantation. For this reason, B cell responses are of particular interest to transplantation research. Rats are important model organisms for transplant studies, but B cell alloimmune assays and B cell subset markers are poorly established in rats. We alloimmunized rats by donor blood injection using the high responder rat strain combination Brown Norway (donor) and Lewis (recipient) rats. Using splenocytes from alloimmunized and control rats, we established assays to assess allospecific B cell proliferation and the capacity to generate allospecific B memory cells and alloantibody-secreting cells after antigenic rechallenge in vitro using a mixed lymphocyte reaction. Furthermore, we defined a simple gating and sorting strategy for pre- and post-germinal center follicular B cells, as well as non-switched and switched plasmablasts. Our protocols for assessing B cell alloresponses and B cell subsets in rats may help to accelerate research into the role of B cells and manipulation of humoral alloresponses in transplant research.
Topics: Animals; B-Lymphocytes; Cell Proliferation; Cells, Cultured; Graft Rejection; Immunity, Humoral; Immunologic Memory; Isoantibodies; Isoantigens; Lymphocyte Activation; Male; Memory B Cells; Phenotype; Rats, Inbred BN; Rats, Inbred Lew; Rats
PubMed: 34971633
DOI: 10.1016/j.jim.2021.113212 -
Transfusion Medicine Reviews Jan 2023RBC alloimmunization remains a significant barrier to ongoing transfusion therapy leading to morbidity, and in extreme cases mortality, due to delayed or insufficient... (Review)
Review
RBC alloimmunization remains a significant barrier to ongoing transfusion therapy leading to morbidity, and in extreme cases mortality, due to delayed or insufficient units of compatible RBCs. In addition, the monitoring and characterization of alloantibodies, often with multiple specificities in a single patient, consumes substantial health care resources. Extended phenotypic matching has mitigated, but not eliminated, RBC alloimmunization and is only logistically available for specialized populations. Thus, RBC alloimmunization remains a substantial problem. In recent decades it has become clear that mechanisms of RBC alloimmunization are distinct from other antigens and lack of mechanistic understanding likely contributes to the fact that there are no approved interventions to prevent RBC alloimmunization from transfusion. The combination of human studies and murine modeling have identified several key factors in RBC alloimmunization. In both humans and mice, immunogenicity is a function of alloantigen copy number on RBCs. Murine studies have further shown that copy number not only changes rates of immunization but the mechanisms of antibody formation. This review summarizes the current understanding of quantitative and qualitative effects of alloantigen copy number on RBC alloimmunization.
Topics: Humans; Mice; Animals; Isoantigens; DNA Copy Number Variations; Erythrocytes; Blood Transfusion; Isoantibodies
PubMed: 36725483
DOI: 10.1016/j.tmrv.2022.12.009 -
Asian Journal of Transfusion Science 2020Alloimmunization is an immune response against foreign antigens which introduced into the body through transfusion, pregnancy, or transplantation. This phenomenon is a... (Review)
Review
BACKGROUND
Alloimmunization is an immune response against foreign antigens which introduced into the body through transfusion, pregnancy, or transplantation. This phenomenon is a big challenge in patients, which require regular transfusions. In the current study, we tried to have a comprehensive review on the status of alloimmunization in Iran. For this purpose, we searched for papers investigating alloimmunization in transfusion-dependent patients and also in patients with no regular transfusions who are candidate for surgery or who need blood.
METHODS
We searched PubMed, Google Scholar, SID, and MAGIRAN databases using the following keywords: "blood transfusion," "alloimmunization," "alloantibodies," "irregular antibodies," "red cell antibodies," and "Iran." No limitation for the date of publication and language of the papers was defined. All the identified records were then screened for the relevance and duplication.
RESULTS
A total of 22 papers were included in this study. All of the studies were conducted from 1999 to 2016 and providing alloimmunization data from different cities all over of Iran. In general, the results showed that the most prevalent alloantibodies are anti-Kell (anti-K antigen) and anti-Rh system, mainly anti-E, anti-D, anti-C, and anti-c.
CONCLUSION
Anti-Kell and anti-Rh antibodies are the most prevalent antibodies responsible for alloimmunization in Iranian population.
PubMed: 33162697
DOI: 10.4103/ajts.AJTS_137_17 -
Transfusion and Apheresis Science :... Feb 2020Non-invasive fetal HPA-1a typing is a valuable tool to identify the pregnancies at risk of fetal and neonatal alloimmune thrombocytopenia (FNAIT). At present, prenatal... (Review)
Review
Non-invasive fetal HPA-1a typing is a valuable tool to identify the pregnancies at risk of fetal and neonatal alloimmune thrombocytopenia (FNAIT). At present, prenatal determination of the fetus HPA-1a type is performed for diagnostic purposes in pregnancies of HPA-1 alloimmunized women with history of a previous fetus or child with FNAIT. Different approaches have been used to determine the fetal HPA-1a genotype from cell-free fetal DNA (cffDNA) in the mother's plasma, mainly based on real-time PCR. Due to the single nucleotide polymorphism (SNP) between the HPA-1a and HPA-1b allelic sequences, a robust and accurate detection of the fetal genotype is challenging, and the sensitivity of most assays is still limited early in pregnancy. Nowadays, the availability of technologies such as next generation sequencing (NGS) or digital PCR offers unprecedented possibilities of analyzing cell-free DNA (cfDNA)-amplified sequences with very high coverage and high sensitivity. In addition, other interesting approaches using variant sequence enrichment strategies have been recently described. In particular, coamplification at lower denaturation temperature PCR (COLD-PCR) offers a simple and sensitive strategy for noninvasive fetal HPA-1 typing. These novel approaches are explained in more detail in this review. Despite no population-based FNAIT screening programs have so far been implemented, the perspectives in terms of treatment and prevention are changing and less costly high-throughput maternal HPA-1a typing methods have been developed. Altogether, this may lead to the implementation of fetal HPA-1a typing with a broader scope in the future, playing a critical role within FNAIT screening programs.
Topics: Antigens, Human Platelet; Female; Fetus; Humans; Integrin beta3; Pregnancy; Thrombocytopenia, Neonatal Alloimmune
PubMed: 31953107
DOI: 10.1016/j.transci.2019.102708 -
Journal of Clinical Medicine May 2020: Incompatibilities between the mother and unborn baby can cause complications that must be identified early to initiate the appropriate treatment. For example, neonatal... (Review)
Review
: Incompatibilities between the mother and unborn baby can cause complications that must be identified early to initiate the appropriate treatment. For example, neonatal alloimmune thrombocytopenia (NAIT), neonatal alloimmune neutropenia (NAIN), and morbus hemolyticus neonatorum affect children worldwide. : This literature review aims to depict the similarities and differences between these three disorders from a clinical and mechanistic point of view. : The current literature review entailed conducting a systematic search to locate articles on the three conditions. Different electronic databases, including PsycINFO, PubMed, Web of Science, and CINAHL, were searched using the search terms "neonatal alloimmune thrombocytopenia", "neonatal alloimmune neutropenia", "morbus hemolyticus neonatorum", "NAIT", "FNAIT", "fetal", "NAIN", and "hemolytic disease of the newborn". : This review shows that these three diseases are caused by incompatibilities between the maternal and fetal immune systems. Furthermore, these conditions can lead to severe complications that hinder fetal development and cause death if not well managed. Discussion: The current literature review shows that NAIT, NAIN, and morbus hemolyticus neonatorum are rare conditions that occur when the mother produces antibodies against the fetal immune system. Thus, there is a need for the early detection of these conditions to initiate appropriate treatment before the child experiences adverse effects. : The development of NAIT, NAIN, and morbus hemolyticus neonatorum is linked to the production of antibodies against the fetal immune system and fetal antigens. Further studies are required to determine potential interventions to reduce the risk of developing these three conditions.
PubMed: 32422924
DOI: 10.3390/jcm9051470 -
International Journal of General... 2022Sickle cell disease (SCD) and thalassemia are common inherited blood disorders in Saudi Arabia, especially in Jazan Province. Patients with these disorders require...
PURPOSE
Sickle cell disease (SCD) and thalassemia are common inherited blood disorders in Saudi Arabia, especially in Jazan Province. Patients with these disorders require multiple blood transfusions, which may lead to alloimmunization because of mismatched blood group antigens. In this study, we examined the alloimmunization and autoimmunization rates in patients with SCD and thalassemia together with the involved antibodies.
PATIENTS AND METHODS
A cross-sectional study was conducted to review the transfusion history records of patients with SCD and thalassemia at Prince Mohammed bin Nasser Hospital, Jazan Province, Saudi Arabia.
RESULTS
Four-hundred thirty-eight patients (385 with SCD, 52 with β-thalassemia, and 1 with α-thalassemia) were received leukoreduced red cell transfusions. The alloimmunization and autoimmunization rates in patients with SCD were 12.98% and 0.52%, respectively. In patients with thalassemia, the alloimmunization and autoimmunization rates were 13.21% and 3.77%, respectively. The most prevalent antibodies in the study population were anti-E (17.19%) and anti-K (14.06%).
CONCLUSION
The alloimmunization and autoimmunization rates were determined in patients with SCD and thalassemia in Jazan Province, Saudi Arabia. The results highlight the need for extended phenotyping to include ABO, RH (D, C, c, E, e), K, Fy, Fy, Jk and Jk antigens in the screening panel. This will benefit patients to ensure better transfusion practices.
PubMed: 35450032
DOI: 10.2147/IJGM.S360320 -
Annual Review of Pathology Jan 2023While red blood cell (RBC) transfusion is the most common medical intervention in hospitalized patients, as with any therapeutic, it is not without risk. Allogeneic RBC... (Review)
Review
While red blood cell (RBC) transfusion is the most common medical intervention in hospitalized patients, as with any therapeutic, it is not without risk. Allogeneic RBC exposure can result in recipient alloimmunization, which can limit the availability of compatible RBCs for future transfusions and increase the risk of transfusion complications. Despite these challenges and the discovery of RBC alloantigens more than a century ago, relatively little has historically been known regarding the immune factors that regulate RBC alloantibody formation. Through recent epidemiological approaches, in vitro-based translational studies, and newly developed preclinical models, the processes that govern RBC alloimmunization have emerged as more complex and intriguing than previously appreciated. Although common alloimmunization mechanisms exist, distinct immune pathways can be engaged, depending on the target alloantigen involved. Despite this complexity, key themes are beginning to emerge that may provide promising approaches to not only actively prevent but also possibly alleviate the most severe complications of RBC alloimmunization.
Topics: Humans; Erythrocytes; Transfusion Reaction; Isoantibodies; Erythrocyte Transfusion
PubMed: 36351365
DOI: 10.1146/annurev-pathol-042320-110411 -
Frontiers in Immunology 2023Measurement of T cell receptor (TCR) or B cell receptor (BCR) gene utilization may be valuable in monitoring the dynamic changes in donor-reactive clonal populations... (Review)
Review
BACKGROUND
Measurement of T cell receptor (TCR) or B cell receptor (BCR) gene utilization may be valuable in monitoring the dynamic changes in donor-reactive clonal populations following transplantation and enabling adjustment in therapy to avoid the consequences of excess immune suppression or to prevent rejection with contingent graft damage and to indicate the development of tolerance.
OBJECTIVE
We performed a review of current literature to examine research in immune repertoire sequencing in organ transplantation and to assess the feasibility of this technology for clinical application in immune monitoring.
METHODS
We searched MEDLINE and PubMed Central for English-language studies published between 2010 and 2021 that examined T cell/B cell repertoire dynamics upon immune activation. Manual filtering of the search results was performed based on relevancy and predefined inclusion criteria. Data were extracted based on study and methodology characteristics.
RESULTS
Our initial search yielded 1933 articles of which 37 met the inclusion criteria; 16 of these were kidney transplant studies (43%) and 21 were other or general transplantation studies (57%). The predominant method for repertoire characterization was sequencing the CDR3 region of the TCR β chain. Repertoires of transplant recipients were found to have decreased diversity in both rejectors and non-rejectors when compared to healthy controls. Rejectors and those with opportunistic infections were more likely to have clonal expansion in T or B cell populations. Mixed lymphocyte culture followed by TCR sequencing was used in 6 studies to define an alloreactive repertoire and in specialized transplant settings to track tolerance.
CONCLUSION
Methodological approaches to immune repertoire sequencing are becoming established and offer considerable potential as a novel clinical tool for pre- and post-transplant immune monitoring.
Topics: B-Lymphocytes; Immune Tolerance; Kidney Transplantation; Organ Transplantation; Humans; T-Lymphocytes; Graft Rejection
PubMed: 36865546
DOI: 10.3389/fimmu.2023.1100479 -
Circulation Research Sep 2020Transplant arteriosclerosis is the major limitation to long-term survival of solid organ transplantation. Although both immune and nonimmune cells have been suggested to...
RATIONALE
Transplant arteriosclerosis is the major limitation to long-term survival of solid organ transplantation. Although both immune and nonimmune cells have been suggested to contribute to this process, the complex cellular heterogeneity within the grafts, and the underlying mechanisms regulating the disease progression remain largely uncharacterized.
OBJECTIVE
We aimed to delineate the cellular heterogeneity within the allografts, and to explore possible mechanisms underlying this process.
METHODS AND RESULTS
Here, we reported the transcriptional profiling of 11 868 cells in a mouse model of transplant arteriosclerosis by single-cell RNA sequencing. Unbiased clustering analyses identified 21 cell clusters at different stages of diseases, and focused analysis revealed several previously unknown subpopulations enriched in the allografts. Interestingly, we found evidence of the local formation of tertiary lymphoid tissues and suggested a possible local modulation of alloimmune responses within the grafts. Intercellular communication analyses uncovered a potential role of several ligands and receptors, including and , in regulating lymphatic endothelial cell-induced early chemotaxis and infiltration of immune cells. In vivo mouse experiments confirmed the therapeutic potential of CCL21 and CXCR3 neutralizing antibodies in transplant arteriosclerosis. Combinational use of genetic lineage tracing and single-cell techniques further indicate the infiltration of host-derived c-Kit stem cells as heterogeneous populations in the allografts. Finally, we compared the immune response between mouse allograft and atherosclerosis models in single-cell RNA-seq analysis. By analyzing susceptibility genes of disease traits, we also identified several cell clusters expressing genes associated with disease risk.
CONCLUSIONS
Our study provides a transcriptional and cellular landscape of transplant arteriosclerosis, which could be fundamental to understanding the initiation and progression of this disease. CCL21/CXCR3 was also identified as important regulators of immune response and may serve as potential therapeutic targets in disease treatment.
Topics: Animals; Aorta; Arteriosclerosis; Cell Lineage; Chemokine CCL21; Disease Models, Animal; Female; Gene Expression Profiling; Graft Survival; Immunity, Cellular; Immunity, Innate; Male; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Transgenic; Proto-Oncogene Proteins c-kit; RNA-Seq; Receptors, CXCR3; Single-Cell Analysis; Time Factors; Transcriptome; Transplantation Tolerance
PubMed: 32689904
DOI: 10.1161/CIRCRESAHA.119.316470 -
IL-21-producing effector Tfh cells promote B cell alloimmunity in lymph nodes and kidney allografts.JCI Insight Oct 2023Follicular helper T (Tfh) cells have been implicated in controlling rejection after allogeneic kidney transplantation, but the precise subsets, origins, and functions of...
Follicular helper T (Tfh) cells have been implicated in controlling rejection after allogeneic kidney transplantation, but the precise subsets, origins, and functions of Tfh cells in this process have not been fully characterized. Here we show that a subset of effector Tfh cells marked by previous IL-21 production is potently induced during allogeneic kidney transplantation and is inhibited by immunosuppressive agents. Single-cell RNA-Seq revealed that these lymph node (LN) effector Tfh cells have transcriptional and clonal overlap with IL-21-producing kidney-infiltrating Tfh cells, implicating common origins and developmental trajectories. To investigate the precise functions of IL-21-producing effector Tfh cells in LNs and allografts, we used a mouse model to selectively eliminate these cells and assessed allogeneic B cell clonal dynamics using a single B cell culture system. We found that IL-21-producing effector Tfh cells were essential for transplant rejection by regulating donor-specific germinal center B cell clonal dynamics both systemically in the draining LN and locally within kidney grafts. Thus, IL-21-producing effector Tfh cells have multifaceted roles in Ab-mediated rejection after kidney transplantation by promoting B cell alloimmunity.
Topics: Mice; Animals; T Follicular Helper Cells; T-Lymphocytes, Helper-Inducer; Lymph Nodes; Kidney; Allografts
PubMed: 37870962
DOI: 10.1172/jci.insight.169793