title: Dynamic expression of Qa-2 during acute graft rejection.
abstract: Human leukocyte antigen (HLA)-G exhibits immunotolerogenicity and is related to allograft acceptance. Qa-2 is the murine homolog of HLA-G; it has structure and functions similar to those of HLA-G. We investigated the dynamic expression of Qa-2 in skin allografts by immunohistochemistry and on peripheral blood lymphocyte subsets by flow cytometry during the entire process of acute graft rejection (AGR) with a murine skin transplantation model to determine its relationship with the pathological changes of allografts and the influence of immunosuppressive therapy. In grafts without immunosuppressive treatment, Qa-2 did not exhibit obvious changes in syngeneic and allogeneic recipients. In contrast, with immunosuppressant-treated grafts, positive expression of Qa-2 was observed. It remained at high levels in the immunosuppressant-treated syngeneic group; however, it became weakly positive and even negative in infiltrating inflammatory cells as AGR advanced, but it remained strongly positive in other skin tissues throughout the AGR process. Qa-2 expression on CD4(+) and CD8(+) peripheral blood lymphocyte subsets remained stable at a normal level in the non-immunosuppressant-treated syngeneic group. Immunosuppressive treatment can also significantly upregulate Qa-2. In the allogeneic groups, decreased expression was observed when AGR was at histological grades 1 to 2 (well before gross rejection was observed). Qa-2 was upregulated again after the graft was rejected completely. The results suggest that the increase in Qa-2 may be attributed to the use of immunosuppressive treatments. Moreover, Qa-2 expression decreased significantly with AGR progression, suggesting that it may be a potential marker for predicting AGR, especially in the presence of immunosuppressive agents.
authors.affiliation: Institute of Diagnostics, School of Medicine, Shandong University, Jinan, P R China.
authors.forename: Nan
authors.initials: N
authors.lastname: Lu
authors.forename: Chuanxin
authors.initials: C
authors.lastname: Wang
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Yang
authors.forename: Shengmei
authors.initials: S
authors.lastname: Zhao
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Li
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Jiang
authors.forename: Jinbo
authors.initials: J
authors.lastname: Feng
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiong
authors.initials: X
authors.lastname: Zou
mesh_terms: D000208:Acute Disease; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism; D062109:Dermatologic Surgical Procedures; D018450:Disease Progression; D005434:Flow Cytometry; D006084:Graft Rejection / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis*; D007150:Immunohistochemistry; D007166:Immunosuppressive Agents / Q000494:pharmacology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D012867:Skin / Q000187:drug effects / Q000378:metabolism*; D016038:Skin Transplantation / Q000009:adverse effects / Q000379:methods*; D013997:Time Factors; D014184:Transplantation, Homologous; D014185:Transplantation, Isogeneic
chemical_list: D015395:Histocompatibility Antigens Class I; D007166:Immunosuppressive Agents; C032907:Q surface antigens