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Transfusion and Apheresis Science :... Oct 2021
Spotlight on the latest trends on CoV-2 Alpha and Delta variants in the UK; Targeting blood donor population for assessing the effect of the mRNA vaccines on the seroprevalence of CoV-2 Delta variant antibodies and reflections on the management of alloimmunisation in transfused patients with...
Topics: Anemia, Hemolytic, Autoimmune; Blood Donors; COVID-19; Humans; RNA, Messenger; SARS-CoV-2; Seroepidemiologic Studies; United Kingdom; Vaccines
PubMed: 34483033
DOI: 10.1016/j.transci.2021.103255 -
International Journal of Molecular... Sep 2023Red blood cell (RBC) transfusion remains a critical component in caring for the acute and chronic complications of sickle cell disease (SCD). Patient alloimmunisation is...
Red blood cell (RBC) transfusion remains a critical component in caring for the acute and chronic complications of sickle cell disease (SCD). Patient alloimmunisation is the main limitation of transfusion, which can worsen anaemia and lead to delayed haemolytic transfusion reaction or transfusion deadlock. Although biological risk factors have been identified for immunisation, patient alloimmunisation remains difficult to predict. We aimed to characterise genetic alloimmunisation factors to optimise the management of blood products compatible with extended antigen matching to ensure the self-sufficiency of labile blood products. Considering alloimmunisation in other clinical settings, like pregnancy and transplantation, many studies have shown that HLA Ib molecules (HLA-G, -E, and -F) are involved in tolerance mechanism; these molecules are ligands of immune effector cell receptors (LILRB1, LILRB2, and KIR3DS1). Genetic polymorphisms of these ligands and receptors have been linked to their expression levels and their influence on inflammatory and immune response modulation. Our hypothesis was that polymorphisms of genes and of their receptors are associated with alloimmunisation susceptibility in SCD patients. The alloimmunisation profile of thirty-seven adult SCD patients was analysed according to these genetic polymorphisms and transfusion history. Our results suggest that the alloimmunisation of SCD patients is linked to both and genetic polymorphisms located in their regulatory region and associated with their protein expression level.
Topics: Adult; Female; Pregnancy; Humans; Leukocyte Immunoglobulin-like Receptor B1; Ligands; Genes, MHC Class I; Anemia, Sickle Cell; Anemia, Hemolytic, Autoimmune; Antigens, CD
PubMed: 37686397
DOI: 10.3390/ijms241713591 -
The Veterinary Clinics of North... Jun 2024Alloimmune disorders occur in foals when pregnant mares produce antibodies against antigens on the foal's cells or tissues, and concentrate them within colostrum. Once... (Review)
Review
Alloimmune disorders occur in foals when pregnant mares produce antibodies against antigens on the foal's cells or tissues, and concentrate them within colostrum. Once foals nurse and absorb colostral antibodies, they can develop hematologic or cutaneous manifestations that can occur individually or in combination. These include neonatal isoerythrolysis, a hemolytic anemia directed against factors on the foal's erythrocytes, alloimmune thrombocytopenia when the antibodies are directed against platelet antigens, alloimmune neutropenia when they are directed against neutrophil antigens, and a combination of suspected alloimmune ulcerative dermatitis, neutropenia and thrombocytopenia. Foals can also develop neutrophilic dermatitis which is suspected to be alloimmune.
PubMed: 38852013
DOI: 10.1016/j.cveq.2024.05.001 -
Current Opinion in Hematology Nov 2020The purpose of this review is to summarize the role of complement in regulating the removal of a target alloantigen following an incompatible red blood cell (RBC)... (Review)
Review
PURPOSE OF REVIEW
The purpose of this review is to summarize the role of complement in regulating the removal of a target alloantigen following an incompatible red blood cell (RBC) transfusion, the formation of alloantibodies following RBC alloantigen exposure, and the development of hyperhemolysis in patients with sickle cell disease (SCD).
RECENT FINDINGS
Recent studies demonstrate that complement can accelerate alloantibody-mediated removal of target alloantigens from the RBC surface following incompatible transfusion. Complement also influences alloantigen availability during developing alloimmune responses and serves as a unique mediator of CD4 T-cell-independent alloantibody formation following RBC alloantigen exposure. Finally, alternative complement pathway activation appears to play a key role in the development of acute hemolytic episodes in patients with SCD, providing a potential druggable target to prevent acute complications in patients with this disease.
SUMMARY
Recent studies suggest that complement can regulate a wide variety of processes germane to hematology, from transfusion complications to baseline hemolysis in patients with SCD. As the role of complement in various disease processes becomes more fully understood, the ability to leverage recently developed complement modulating drugs will only continue to enhance providers' ability to favorably intervene in many hematological diseases.
Topics: Anemia, Hemolytic, Autoimmune; Animals; Blood Group Incompatibility; Complement System Proteins; Erythrocyte Transfusion; Erythrocytes; Hemolysis; Humans; Isoantibodies; Isoantigens
PubMed: 32889827
DOI: 10.1097/MOH.0000000000000610 -
Current Opinion in Organ Transplantation Dec 2019The microbiota in mammalian hosts can affect maturation and function of the immune system and has been associated with health and disease. We will review new findings on... (Review)
Review
PURPOSE OF REVIEW
The microbiota in mammalian hosts can affect maturation and function of the immune system and has been associated with health and disease. We will review new findings on how this dynamic environmental factor impacts alloimmunity and therapy in transplant hosts.
RECENT FINDINGS
The microbiota changes after transplantation and immunosuppressive therapy. New data indicate that different microbial community structures have distinct impact on graft outcome, from promoting, to inhibiting or being neutral to transplant survival. In addition, we will address reciprocal interactions between the microbiota and immunosuppressive drugs, as well as the suitability of the microbiota as a predictive biomarker and its utility as adjunct therapy in transplantation.
SUMMARY
Advances in microbiome sequencing and wider availability of gnotobiotic facilities are enabling mechanistic investigations into the commensal communities and pathways that modulate allograft outcome, responsiveness to immunosuppression and side effects of drugs. A better understanding of the functions of the microbiota may help mitigate drug toxicity, predict drug dosage and dampen alloimmunity in transplant patients.
Topics: Graft Survival; Humans; Microbiota; Organ Transplantation
PubMed: 31577594
DOI: 10.1097/MOT.0000000000000702 -
Transfusion Medicine (Oxford, England) Jun 2022To demonstrate the feasibility and effectiveness of extended matching of red blood cells (RBC) in practice.
OBJECTIVE
To demonstrate the feasibility and effectiveness of extended matching of red blood cells (RBC) in practice.
BACKGROUND
At present, alloimmunisation preventing matching strategies are only applied for specific transfusion recipient groups and include a limited number of RBC antigens. The general assumption is that providing fully matched RBC units to all transfusion recipients is not feasible. In this article we refute this assumption and compute the proportion of alloimmunisation that can be prevented, when all donors and transfusion recipients are typed for A, B, D plus twelve minor blood group antigens (C, c, E, e, K, Fy , Fy , Jk , Jk , M, S and s).
METHODS
We developed a mathematical model that determines the optimal sequence for antigen matching. The model allows for various matching strategies, issuing policies and inventory sizes.
RESULTS
For a dynamic inventory composition (accounting for randomness in the phenotypes supplied and requested) and an antigen identical issuing policy 97% and 94% of alloimmunisation events can be prevented, when respectively one and two RBC units per recipient are requested from an inventory of 1000 units. Although this proportion decreases with smaller inventory sizes, even for an inventory of 60 units almost 50% of all alloimmunisation events can be prevented.
CONCLUSION
In case antigen of both donors and recipients are comprehensively typed, extended preventive matching is feasible for all transfusion recipients in practice and will significantly reduce transfusion-induced alloimmunisation and (alloantibody-induced) haemolytic transfusion reactions.
Topics: Anemia, Hemolytic, Autoimmune; Blood Grouping and Crossmatching; Blood Transfusion; Erythrocytes; Humans; Isoantibodies; Transfusion Reaction
PubMed: 34845765
DOI: 10.1111/tme.12831 -
Transfusion and Apheresis Science :... Dec 2021Transfusion is a lifesaving treatment for lots of patients. However, in chronic blood recipients such as thalassemia patients, there are high concerns about alloantibody...
BACKGROUND
Transfusion is a lifesaving treatment for lots of patients. However, in chronic blood recipients such as thalassemia patients, there are high concerns about alloantibody production that affects the quality of their life. Therefore, research on risk factors of alloimmunization has been started and followed. This study aimed at the determination of correlation probability between some HLADRB1 alleles and alloimmunization in Iranian thalassemia patients.
MATERIALS AND METHODS
The present study was conducted on 60 alloimmunized and 60 non-alloimmunized transfusion-dependent thalassemia patients. Antibody screening and identification tests were carried out using the tube method, and HLA-DRB1 genotyping was done using a single specific primer-polymerase chain reaction (PCRSSP).
RESULTS
The results of antibody screening showed that the most prevalent alloantibodies were Anti-K (46.7 %), and followed by Anti-E (32.5 %), Anti-C (15.8 %), Anti-D (13.3 %), Anti-e (8 %), and Anti-c (5.8 %), respectively. DRB1*07:01 was detected more in non-responder patients (28.3 %). However, data analysis showed that there is no significant relationship between DRB1*07:01, *10, *13:01 frequency among responder and non-responder groups (p = 0·195, 0.648, 0.402, respectively). There was not any significant correlation between HLA-DRB1*10 and *13:01 allele and alloimmunization. There was a significant association between HLA-DRB1*12 and alloimmunization (p < 0·05, OR = 2.071, CI: 1.716-2.501).
CONCLUSION
The findings of this study represented that there is a significant relationship between HLADRB1*12 and Kell and E alloantibodies. Although more developed studies on other HLA alleles are demanded, these findings can be valuable in determining important alloimmunization risk factors to better management of transfusion complications.
Topics: Alleles; Blood Transfusion; HLA-DRB1 Chains; Humans; Isoantibodies; Prognosis; Thalassemia
PubMed: 34535395
DOI: 10.1016/j.transci.2021.103271 -
World Journal of Gastroenterology Jul 2019The transplanted liver can modulate the recipient immune system to induce tolerance after transplantation. This phenomenon was observed nearly five decades ago.... (Review)
Review
The transplanted liver can modulate the recipient immune system to induce tolerance after transplantation. This phenomenon was observed nearly five decades ago. Subsequently, the liver's role in multivisceral transplantation was recognized, as it has a protective role in preventing rejection of simultaneously transplanted solid organs such as kidney and heart. The liver has a unique architecture and is home to many cells involved in immunity and inflammation. After transplantation, these cells migrate from the liver into the recipient. Early studies identified chimerism as an important mechanism by which the liver modulates the human immune system. Recent studies on human T-cell subtypes, cytokine expression, and gene expression in the allograft have expanded our knowledge on the potential mechanisms underlying immunomodulation. In this article, we discuss the privileged state of liver transplantation compared to other solid organ transplantation, the liver allograft's role in multivisceral transplantation, various cells in the liver involved in immune responses, and the potential mechanisms underlying immunomodulation of host alloresponses.
Topics: Allografts; Graft Rejection; Graft Survival; Humans; Immune Tolerance; Liver; Organ Transplantation; Transplantation, Homologous
PubMed: 31333306
DOI: 10.3748/wjg.v25.i25.3123 -
Biomedicines Jun 2022The polymorphic human leukocyte antigen (HLA) system has been considered the main target for alloimmunity, but the non-HLA antibodies and autoimmunity have gained... (Review)
Review
The polymorphic human leukocyte antigen (HLA) system has been considered the main target for alloimmunity, but the non-HLA antibodies and autoimmunity have gained importance in kidney transplantation (KT). Apart from the endothelial injury, secondary self-antigen exposure and the presence of polymorphic alloantigens, respectively, auto- and allo- non-HLA antibodies shared common steps in their development, such as: antigen recognition via indirect pathway by recipient antigen presenting cells, autoreactive T cell activation, autoreactive B cell activation, T helper 17 cell differentiation, loss of self-tolerance and epitope spreading phenomena. Both alloimmunity and autoimmunity play a synergic role in the formation of non-HLA antibodies, and the emergence of transcriptomics and genome-wide evaluation techniques has led to important progress in understanding the mechanistic features. Among them, non-HLA mismatches between donors and recipients provide valuable information regarding the role of genetics in non-HLA antibody immunity and development.
PubMed: 35884811
DOI: 10.3390/biomedicines10071506 -
Transfusion Medicine Reviews Oct 2020Despite significant advancements in the production of platelet products, storage, and transfusion, transfusion refractoriness remains a significant clinical problem,... (Review)
Review
Despite significant advancements in the production of platelet products, storage, and transfusion, transfusion refractoriness remains a significant clinical problem, affecting up to 14% of hematological patients receiving platelet transfusions. Human leukocyte antigen (HLA) alloimmunization is a major cause of immune platelet refractoriness, and its rate can be significantly reduced by implementation of leukoreduction. Despite promising preclinical results, pathogen reduction does not reduce HLA alloimmunization. Patients with HLA alloimmune refractoriness are usually managed with HLA-selected platelet transfusions. In this review, we describe the pathophysiology of HLA alloimmunization and alloimmune refractoriness, as well as options to prevent and treat these transfusion complications. We discuss the evidence supporting these options and point out the outstanding gaps. Finally, we review the possible future directions for prevention and treatment of alloimmune refractoriness.
Topics: Blood Platelets; HLA Antigens; Humans; Isoantibodies; Platelet Count; Platelet Transfusion; Thrombocytopenia; Treatment Failure
PubMed: 33127210
DOI: 10.1016/j.tmrv.2020.09.010