Immune Cell Composition and Graft-Versus-Host Disease

Allogeneic hematopoietic stem cell transplantation (AHSCT) hasrevolutionized the curative approaches of malignant and non-malignanthematological disorders. The grafted cells are an amalgam of stemcells, T cells, B cells, natural killer (NK) cells, and other immune andstromal cells that can be beneficial or injurious based on the purposeof treatment. One of the most serious and pernicious complications ofAHSCT is unwanted priming of grafted allogeneic-T cells against thehost s tissues leading to graft-versus-host disease (GvHD) and has a highrate of incidence, morbidity, and mortality. A wide range of approachesto control the GvHD are currently under research among which thepreventive approaches is the most desirable to fulfill. Graft manipulationbefore transplantation is one of the interesting areas to decrease theprobability of GvHD. Whole T cell depletion was the first choice led toa dramatic decrease of GvHD incidence but the curative effects of graftversus-leukemia (GvL) were also abolished. Recent studies have focusedon manipulation or mitigation of some harmful alloreactive-T cell orother immune cell subsets such as ab T Cells, CD45RA-expressing naiveT cells, B cells, and dendritic cells while preserving the functionalityof tumor-reactive NK cells and gd T cells. Another approach is to usethe immune-modulating cells such as regulatory T cells, mesenchymalstromal cells, and tolerogenic dendritic cells as well as cytokines likeIL-22 to ameliorate the severity of GvHD. The diversity of methods andtargets and their pros and cons for preventing GvHD and preserving GvLmake an interesting and controversial era of study.

کلیدواژه ها:

Graft-versus-host disease ، Immune cell subsets ، Graft manipulation