Determination of soluble HLA-G serum levels in patients with adenomyosis and uterine fibroids before and after surgery

Adenomyosis is a benign gynaecological disease caused by the growth of endometrial tissue in the myometrium that affects approximately 30 % of child-bearing-age women. We evaluated the levels of soluble human leukocyte antigen G (sHLA-G) in the serum of patients with adenomyosis before and after treatment. Serum samples of 34 patients with adenomyosis and 31 patients with uterine fibroids were collected before and after the operation and were analysed for sHLA-G levels byELISAassay. The preoperative levels of serum sHLA-G in the adenomyosis group (28.05 ± 2.466 ng/ml) were significantly higher than those in the uterine fibroid group (18.53 ± 1.435 ng/ml) (P < 0.05). Serum sHLA-G levels in the adenomyosis group showed a decreasing trend at different time points after surgery (28.05 ± 14.38 ng/ml, 18.41 ± 8.34 ng/ml, and 14.45 ± 5.77 ng/ml). Adenomyosis patients who underwent total hysterectomy (n = 20) had a more significant decrease in sHLA-G levels in the early postoperative period (2 days post-operative) than those who underwent partial hysterectomy (n = 14). These results suggest that immunologic dysfunctions may be detected in patients with adenomyosis.

10-Year Experience with HLA-G in Heart Transplantation

The Human Leukocyte Antigen-G (HLA-G) is a MHC-class Ib molecule with robust immunomodulatory properties; in transplant, it inhibits cytotoxic activity of immune cells and thus has a pivotal role in protecting the allograft from immune attack. The present review details a 10-year experience investigating the influence of HLA-G on heart transplantation, allograft rejection and cardiac allograft vasculopathy development. Exploration of HLA-G in transplantation began with the initial findings of its increased expression in allograft hearts. Since then, HLA-G has been recognized as an important factor in transplant immunology. We discuss inducers of HLA-G expression, and the importance of HLA-G as a potential biomarker in allograft rejection and heart failure. We also highlight the importance of polymorphisms and how they may influence both HLA-G expression and clinical outcomes. There remains much to be done in this field, however we hope that findings from our group and other groups will ignite interest and facilitate further expansion of HLA-G research in transplantation.

Soluble Human Leukocyte Antigen-G in the Bronchoalveolar Lavage of Lung Cancer Patients

BACKGROUND

The main function of the HLA-G molecule in its membrane-bound and soluble forms is to inhibit the immune response by acting on CD4+ T cells, cytotoxic T cells, NK cells and dendritic cells. Lung cancer is a leading cause of death worldwide, and annual incidence is high in both women and men. Some studies have reported an increase of HLA-G serum levels in lung cancer, probably generated by tumor cells escaping the antitumor immune response. In this study the concentration of soluble HLA-G in bronchoalveolar lavage (BAL) in patients with primary and metastatic lung cancer was measured to determine its relation with tumor histological type and overall patient status according to the Karnofsky scale.

METHODS

Thirty-one lung cancer patients were included. A tumor biopsy was obtained by bronchoscopy and the tumor type was determined by hematoxylin and eosin staining. BAL samples were obtained to measure soluble HLA-G concentrations in an ELISA sandwich assay.

RESULTS

The average value of soluble HLA-G was 49.04ng/mL. No correlation between soluble HLA-G levels and age, gender or smoking was observed. A highly significant difference was observed in the levels of soluble HLA-G in BAL from patients with different histological types of lung cancer, especially in metastatic tumors. The Karnofsky index showed a significant and inverse correlation with soluble HLA-G levels in BAL.

CONCLUSIONS

Soluble HLA-G protein is significantly associated with metastatic tumors and patients with lower Karnofsky index and may be useful as a prognostic marker in lung cancer.

New Developments in HLA-G in Cardiac Transplantation

Human Leukocyte Antigen-G (HLA-G) is a non-classical class 1b protein, whose gene is located on chromosome 6 (6p21.31). HLA-G inhibits the immune cells' cytotoxic activity by interacting with specific receptors on their membranes. Since it is a naturally occurring immune modulator, HLA-G has been investigated in transplantation. Indeed, a number of investigations reveal that HLA-G expression is influenced by genetic polymorphisms and in turn, those polymorphisms are associated with detrimental or beneficial outcomes in various pathological situations. The present review introduces the HLA-G molecule, the gene and its polymorphisms. It focuses on the expression of HLA-G and the role of polymorphisms primarily in heart transplant outcomes, secondarily in other transplant organs, as well as the role of the allograft and effect of medical therapy. We discuss the limitations in HLA-G transplant investigations and future directions. The immune inhibiting activity of HLA-G has a great deal of potential for its utilization in enhancing diagnostic, preventive and therapeutic strategies against rejection in the setting of transplantation.