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Frontiers in Immunology 2020The risk and severity of specific infections are increased during pregnancy due to a combination of physiological and immunological changes. Characterizing the maternal... (Review)
Review
The risk and severity of specific infections are increased during pregnancy due to a combination of physiological and immunological changes. Characterizing the maternal immune system during pregnancy is important to understand how the maternal immune system maintains tolerance towards the allogeneic fetus. This may also inform strategies to prevent maternal fatalities due to infections and optimize maternal vaccination to best protect the mother-fetus dyad and the infant after birth. In this review, we describe what is known about the immunological changes that occur during a normal pregnancy.
Topics: Adaptive Immunity; Animals; Female; Histocompatibility, Maternal-Fetal; Humans; Immune System; Immunity, Cellular; Immunity, Humoral; Immunity, Innate; Maternal-Fetal Exchange; Pregnancy; Pregnancy Complications
PubMed: 33133091
DOI: 10.3389/fimmu.2020.575197 -
Targeted Disruption of HLA Genes via CRISPR-Cas9 Generates iPSCs with Enhanced Immune Compatibility.Cell Stem Cell Apr 2019Induced pluripotent stem cells (iPSCs) have strong potential in regenerative medicine applications; however, immune rejection caused by HLA mismatching is a concern. B2M...
Induced pluripotent stem cells (iPSCs) have strong potential in regenerative medicine applications; however, immune rejection caused by HLA mismatching is a concern. B2M gene knockout and HLA-homozygous iPSC stocks can address this issue, but the former approach may induce NK cell activity and fail to present antigens, and it is challenging to recruit rare donors for the latter method. Here, we show two genome-editing strategies for making immunocompatible donor iPSCs. First, we generated HLA pseudo-homozygous iPSCs with allele-specific editing of HLA heterozygous iPSCs. Second, we generated HLA-C-retained iPSCs by disrupting both HLA-A and -B alleles to suppress the NK cell response while maintaining antigen presentation. HLA-C-retained iPSCs could evade T cells and NK cells in vitro and in vivo. We estimated that 12 lines of HLA-C-retained iPSCs combined with HLA-class II knockout are immunologically compatible with >90% of the world's population, greatly facilitating iPSC-based regenerative medicine applications.
Topics: Animals; CRISPR-Cas Systems; Cell Line; Female; Gene Editing; HLA Antigens; Histocompatibility; Humans; Induced Pluripotent Stem Cells; Male; Mice; Mice, Inbred NOD
PubMed: 30853558
DOI: 10.1016/j.stem.2019.02.005 -
Acta Ophthalmologica Scandinavica Feb 2004
Topics: Corneal Transplantation; Denmark; Histocompatibility; Histocompatibility Antigens; Histocompatibility Testing; Humans; Major Histocompatibility Complex
PubMed: 14738482
DOI: 10.1111/j.1395-3907.2004.00221.x -
Current Opinion in Organ Transplantation Aug 2015
Technical and conceptual advances in histocompatibility and immunogenetics inform on mechanisms of transplant rejection and pave the way to development of novel therapies.
Topics: Graft Rejection; Histocompatibility; Humans; Immunogenetics; Periodicals as Topic; Transplantation Immunology
PubMed: 26126199
DOI: 10.1097/MOT.0000000000000219 -
Current Biology : CB Mar 2015Since ancient times, people have cut and joined together plants of different varieties or species so they would grow as a single plant - a process known as grafting...
Since ancient times, people have cut and joined together plants of different varieties or species so they would grow as a single plant - a process known as grafting (Figures 1 and 2). References to grafting appear in the Bible, ancient Greek and ancient Chinese texts, indicating that grafting was practised in Europe, the Middle East and Asia by at least the 5(th) century BCE. It is unknown where or how grafting was first discovered, but it is likely that natural grafting, the process by which two plants touch and fuse limbs or roots in the absence of human interference (Figure 3), influenced people's thinking. Such natural grafts are generally uncommon, but are seen in certain species, including English ivy. Parasitic plants, such as mistletoe, that grow and feed on often unrelated species may have also contributed to the development of grafting as a technique, as people would have observed mistletoe growing on trees such as apples or poplars.
Topics: Histocompatibility; Plant Breeding; Plant Physiological Phenomena; Plant Vascular Bundle; Transplants
PubMed: 25734263
DOI: 10.1016/j.cub.2015.01.029 -
Frontiers in Immunology 2022The transcriptional regulation of B-cell response to antigen stimulation is complex and involves an intricate network of dynamic signals from cytokines and transcription... (Review)
Review
The transcriptional regulation of B-cell response to antigen stimulation is complex and involves an intricate network of dynamic signals from cytokines and transcription factors propagated from T-cell interaction. Long-term alloimmunity, in the setting of organ transplantation, is dependent on this B-cell response, which does not appear to be halted by current immunosuppressive regimens which are targeted at T cells. There is emerging evidence that shows that B cells have a diverse response to solid organ transplantation that extends beyond plasma cell antibody production. In this review, we discuss the mechanistic pathways of B-cell activation and differentiation as they relate to the transcriptional regulation of germinal center B cells, plasma cells, and memory B cells in the setting of solid organ transplantation.
Topics: B-Lymphocytes; Germinal Center; Graft Rejection; Histocompatibility; Organ Transplantation
PubMed: 36016958
DOI: 10.3389/fimmu.2022.895157 -
Blood Dec 2011Histocompatibility testing for stem cell and solid organ transplantation has become increasingly complex as newly discovered HLA alleles are described. HLA typing...
Histocompatibility testing for stem cell and solid organ transplantation has become increasingly complex as newly discovered HLA alleles are described. HLA typing assignments reported by laboratories are used by physicians and donor registries for matching donors and recipients. To communicate effectively, a common language for histocompatibility terms should be established. In early 2010, representatives from Clinical, Registry, and Histocompatibility organizations joined together as the Harmonization of Histocompatibility Typing Terms Working Group to define a consensual language for laboratories, physicians, and registries to communicate histocompatibility typing information. The Working Group defined terms for HLA typing resolution, HLA matching, and a format for reporting HLA assignments. In addition, definitions of verification typing and extended typing were addressed. The original draft of the Definitions of Histocompatibility Typing Terms was disseminated to colleagues from each organization to gain feedback and create a collaborative document. Commentary gathered during this 90-day review period were discussed and implemented for preparation of this report. Histocompatibility testing continues to evolve; thus, the definitions agreed on today probably will require refinement and perhaps additional terminology in the future.
Topics: Allergy and Immunology; Guidelines as Topic; Histocompatibility; Humans; Terminology as Topic; Transplantation Immunology
PubMed: 22001389
DOI: 10.1182/blood-2011-05-353490 -
Revista Da Associacao Medica Brasileira... Oct 2016To review and discuss the literature on hematopoietic stem cell transplantation (HSCT) with haploidentical donors in Brazil. (Review)
Review
OBJECTIVE
To review and discuss the literature on hematopoietic stem cell transplantation (HSCT) with haploidentical donors in Brazil.
METHOD
Literature review.
RESULTS
The haploidentical hematopoietic stem cell transplantations have become a safe option in hematology since the 80s, with the possibility of ex-vivo T-cell depletion. However, its broad use worldwide occurred with the advent of haploidentical nonmyeloablative transplants using in vivo T-cell depletion with the administration of post-transplant cyclophosphamide. The results were encouraging, despite the increased risk of infection and post-transplantation recurrence. Recent publications on acute myeloid leukemia, myelodysplastic syndrome and Hodgkin's lymphoma have shown similar results among haploidentical, unrelated and related full-match transplants. Obviously, these findings of retrospective studies should be confirmed by clinical trials.
CONCLUSIONS
Transplantation with haploidentical donor has shown to be feasible in Brazil and the first publications and results are showing encouraging results.
Topics: Brazil; Donor Selection; Hematopoietic Stem Cell Transplantation; Histocompatibility; Humans; Risk Assessment; Time Factors; Tissue Donors; Treatment Outcome
PubMed: 27982315
DOI: 10.1590/1806-9282.62.suppl1.29 -
American Journal of Transplantation :... Sep 2022
Topics: Graft Rejection; Histocompatibility; Histocompatibility Antigens; Histocompatibility Antigens Class I; Histocompatibility Testing
PubMed: 36039544
DOI: 10.1111/ajt.16672 -
Frontiers in Immunology 2021Heart transplant candidates sensitized to HLA antigens wait longer for transplant, are at increased risk of dying while waiting, and may not be listed at all. The... (Review)
Review
Heart transplant candidates sensitized to HLA antigens wait longer for transplant, are at increased risk of dying while waiting, and may not be listed at all. The increasing prevalence of HLA sensitization and limitations of current desensitization strategies underscore the urgent need for a more effective approach. In addition to pregnancy, prior transplant, and transfusions, patients with end-stage heart failure are burdened with unique factors placing them at risk for HLA sensitization. These include homograft material used for congenital heart disease repair and left ventricular assist devices (LVADs). Moreover, these risks are often stacked, forming a seemingly insurmountable barrier in some cases. While desensitization protocols are typically implemented uniformly, irrespective of the mode of sensitization, the heterogeneity in success and post-transplant outcomes argues for a more tailored approach. Achieving this will require progress in our understanding of the immunobiology underlying the innate and adaptive immune response to these varied allosensitizing exposures. Further attention to B cell activation, memory, and plasma cell differentiation is required to establish methods that durably abrogate the anti-HLA antibody response before and after transplant. The contribution of non-HLA antibodies to the net state of sensitization and the potential implications for graft longevity also remain to be comprehensively defined. The aim of this review is to first bring forth select issues unique to the sensitized heart transplant candidate. The current literature on desensitization in heart transplantation will then be summarized providing context within the immune response. Building on this, newer approaches with therapeutic potential will be discussed emphasizing the importance of not only addressing the short-term pathogenic consequences of circulating HLA antibodies, but also the need to modulate alloimmune memory.
Topics: Female; HLA Antigens; Heart Transplantation; Histocompatibility; Humans; Male; Transplantation Immunology
PubMed: 34504489
DOI: 10.3389/fimmu.2021.702186