study on stress, depression and NK cytotoxic potential in women with recurrent spontaneous abortion

It has been recognized that acute and chronic stress has an impact on the immune system. Acute stress may have a stimulating effect on the immune system, while in the case of chronic stress specially depression, the immune system could be down-regulated. However, an association between depression and a higher number of circulating white blood cells with increased activity has been reported. Elevation in immune cell numbers and alteration in cytokine profiles are documented for women suffering sporadic spontaneous abortion with a high stress score. In spite of these contradictory results and to make a new approach in immunological [NK activity] as well as psychological parameters [stress/depression] in women suffering from recurrent spontaneous abortion [RSA] the present study was planned. Forty-five women with a history of RSA and a matched control group were participated in this study. A questionnaire for life events known as life change units [LCU] and the Beck Depression Inventory [BDI] outlines were used and the socio-psychological events were recorded after visiting and interview. Fresh peripheral blood lymphocytes were taken as a source of NK activity and K562 cell line were used as NK sensitive target. The experiments were performed and the cells were analyzed with a flow-cytometer. The stress and the depression scores were determined 245 +/- 83.6 and 27.6 +/- 8.8 for women with RSA and 224 +/- 79.6 and 19.4 +/- 7.1 for non-RSA group respectively. There was an association between life stress scores and depression scores with r=0.65 and P=0.000 for RSA women. A correlation with r=-0.34 and P=0.02 was found between depression scores and NK cytotoxicity. The Pearson correlation test showed a lack of relationship between high stress score and NK activity with the r=0.011 and P=0.95, but r=-0.30 and P=0.072 was obtained for high depression scores and NK cytotoxicity. Therefore, it could be suggested that in the case of women with a history of recurrent spontaneous abortion, modulation for immunological parameters [i.e immunotherapy] concurrently with managing psychological aspects [stress/depression] could be modified for the benefit of the patients

assessment of NK cytotoxicity and CD56+/CD16+ phenotype by flow cytometry in PBL isolated from women with recurrent spontaneous abortion

Human peripheral blood NK cells constitutively express CD56 and CD16 antigens. Peripheral blood NK cells seem to be strongly related with decidual NK cells, and may reflect the decidual NK cell functional status. There are varied reports concerning the relationship between NK cell cytotoxicity in women with recurrent spontaneous abortion. To study NK activity in women with history of RSA by using a non-radioactive cytotoxicity assay. Peripheral blood lymphocytes from RSA and healthy multiparous women were obtained. Lymphocytes were isolated and mixed with K562 NK-sensitive cell line. A non-radioactive method for NK cell cytotoxicity assessment was utilized. Dead K562 cell populations were detected by FACS Calibur flow cytometry, and the data obtained was analysed on cell-Quest software. The proportion of CD16+/CD56+ cells was then calculated. The proportion of NK cells were 9.21% +/- 3.06 and 13.48% +/- 4.09 in healthy women and RSA, respectively. The percentage of cytotoxicity was determined to be 19.3% +/- 3.9 in healthy group and 27.1% +/- 6.5 in RSA group with an effector:target ratio of 50:1. The data shows an increase in PBLs potential for in vitro cytotoxicity assay in RSA individuals. The analyses indicate that there is a weak positive correlation between NK cytotoxicity potential and the percentage of NK cells in PBL population. The present study demonstrates that the percentage of CD56+/CD16+ cells increases in individuals with recurrent spontaneous abortion. We conclude that NK cytotoxicity as well as NK number is partially involved in RSA