Infectious pathogens may trigger specific allo-HLA reactivity via multiple mechanisms

• Published in: Immunogenetics (New York) Vol. 69; no. 8-9; pp. 631 - 641
• Main Authors: D’Orsogna, Lloyd, van den Heuvel, Heleen, van Kooten, Cees, Heidt, Sebastiaan, Claas, Frans H.J.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2017; Springer Nature B.V
• Subjects: Allergology; Antigen Presentation; Antigen-presenting cells; Antigens; B-Lymphocytes - immunology; Biomedical and Life Sciences; Biomedicine; Blood transfusion; Cell activation; Cell Biology; Cross Reactions; Cross-reactivity; Effectors; Exposure; Gene Function; Graft rejection; Herpesvirus 4, Human - immunology; Histocompatibility antigen HLA; HLA Antigens - immunology; Human Genetics; Humans; Immune response; Immune system; Immunity; Immunity, Innate; Immunologic Memory; Immunological memory; Immunology; Innate immunity; Lymphocyte Activation; Lymphocytes; Lymphocytes B; Lymphocytes T; Memory cells; Pathogens; Pregnancy; Receptors, Antigen, T-Cell - physiology; Rejection; Review; T cell receptors; T-Lymphocytes - immunology; Topical Collection on MHC/KIR in Health and Disease; Transplantation; Transplants & implants; Viruses; Infection; Alloreactivity; B cells; HLA; T cells; Heterologous immunity
• ISSN: 0093-7711; 1432-1211; 1432-1211
• DOI: 10.1007/s00251-017-0989-3

Transplant recipients can be sensitized against allo-HLA antigens by previous transplantation, blood transfusion, or pregnancy. While there is growing awareness that multiple components of the immune system can act as effectors of the alloresponse, the role of infectious pathogen exposure in triggering sensitization and allograft rejection has remained a matter of much debate. Here, we describe that exposure to pathogens may enhance the immune response to allogeneic HLA antigens via different pathways. The potential role of allo-HLA cross-reactivity of virus-specific memory T cells, activation of innate immunity leading to a more efficient induction of the adaptive alloimmune response by antigen-presenting cells, and bystander activation of existing memory B cell activation will be discussed in this review.