[Up-regulation of the sHLA-G5 level by human-mouse chimeric anti-IL-2R monoclonal antibody treatment in kidney transplantation].

Objective: To find whether the up-regulation of soluble human leucocyte antigen-G5 (sHLA-G5) levels is a new function mechanism of anti-interleukin-2 receptors (anti-IL-2R) monoclonal antibody treatment in kidney transplantation.

Methods: A total of 215 recipients at our centre from January 2006 to December 2007 were divided into antibody use group (n = 141) and antibody non-use group (n = 74) and another healthy group (n = 69). The sHLA-G5 level in peripheral blood was detected by enzyme-linked immunosorbent assay (ELISA). And the expression of HLA-G5 was confirmed by Western blot and Real-time polymerase chain reaction (PCR).

Results: sHLA-G5 levels was (56 ± 30) µg/L in using anti-IL-2 receptor monoclonal antibody before transplantation, It was higher than that before use antibody [(34 ± 20) µg/L], also higher than healthy group [(35 ± 17) µg/L] and antibody non-use group [(36 ± 19) µg/L, P < 0.05, respectively]. At Day 1, Day 4, Week 1, Week 2 post-transplantation, the level of sHLA-G5 of recipients with antibody use was significantly higher than that of those with antibody non-use. The values were as follows: (95 ± 35) µg/L vs (54 ± 16) µg/L, (131 ± 24) µg/L vs (75 ± 22) µg/L, (167 ± 44) µg/L vs (62 ± 17) µg/L, (172 ± 35) µg/L vs (45 ± 16) µg/L (all P < 0.01). And the results of Western blot and RT-PCR corresponded to those of ELISA.

Conclusion: The preoperative use of first dose of anti-IL-2R monoclonal antibodies results in the up-regulated level of sHLA-G5. Thus it is beneficial for protecting the kidney survival and reducing the risks of acute rejection.