title: Soluble major histocompatibility complex class I chain-related antigen A level in chronic allograft dysfunction.
abstract: BACKGROUND
  Soluble major histocompatibility complex class I chain-related antigen A (soluble MICA) has recently been considered as an inhibitory molecule which is shed from tumors and protects them against natural killers and some subgroups of T cells' cytolysis. In transplantation, soluble MICA is also a foreign antigenic molecule that can induce allospecific responses. This study aimed to clarify its possible role in long-term kidney allograft outcome.
  
  
  METHODS
  Thirty patients with biopsy-proven chronic allograft dysfunction (CAD) were pair-matched with kidney allograft recipients with 30 stable graft function. Fifteen healthy individuals were enrolled as controls. Soluble MICA antigen and anti-HLA antibodies were measured in their serum.
  
  
  RESULTS
  There was no significant difference between CAD patients, stable recipients, and healthy volunteers in frequency or titer of soluble MICA; however, soluble MICA-positive patients were more frequent in the stable group was than the CAD group (43.4% versus 33.3%). In addition, a high level of soluble MICA was accompanied by enhanced humoral responses. No significant difference was found in anti-HLA antibodies production between the CAD and stable groups.
  
  
  CONCLUSIONS
  Our data suggest that soluble MICA, at least in a defined range, can protect the allograft against natural killers and T cell cytolysis; nonetheless, its excessive amounts might stimulate immune system to exert enhanced humoral response. In order to confirm the protective or detrimental role of soluble MICA in kidney transplantation, conducting larger studies is necessary.
authors: Sara
authors: S
authors: Assadiasl
authors: Pedram
authors: P
authors: Ahmadpoor
authors: Mohsen
authors: M
authors: Nafar
authors: Mahboob
authors: M
authors: Lesan Pezeshki
authors: Peyman
authors: P
authors: Mohammadi Torbati
authors: Mohammad Hosein
authors: MH
authors: Nicknam
authors: Department of Immunology, Medical school, Tehran University of medical sciences, Pour Sina Ave, Tehran, Iran. amirzara@sina.tums.ac.ir.
authors: Aliakbar
authors: A
authors: Amirzargar
mesh_terms: D000368:Aged; D064591:Allografts / Q000276:immunology*; D000906:Antibodies / Q000097:blood*; D016022:Case-Control Studies; D005260:Female; D006084:Graft Rejection / Q000097:blood / Q000276:immunology*; D006085:Graft Survival / Q000276:immunology; D006680:HLA Antigens / Q000276:immunology*; D015395:Histocompatibility Antigens Class I / Q000097:blood*; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects* / Q000379:methods; D008297:Male; D008875:Middle Aged
chemical_list: D000906:Antibodies; D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A