No difference in natural-killer-T cell population, but Th2/Tc2 predominance in peripheral blood of recurrent aborters.

PROBLEM: The aim of this study was to assess the natural-killer-T (NKT) cell population and cytokine expression in the peripheral blood of women with a history of recurrent spontaneous abortion (RSA).

METHOD OF STUDY: The percentages of CD3+ CD4- CD8- TCRValpha24+ Vbeta11+-NKT cells and cells expressing intracellular interferon (IFN)-gamma, interleukin (IL)-4, and tumor necrosis factor (TNF)-alpha either with CD4+ or CD8+ cells were measured by flow cytometry at the midluteal phases in 15 RSA women and 15 fertile control women.

RESULTS

No significant differences in the NKT cell percentages were found between RSA and control women. However, in RSA women, the CD4+ IL-4+ cell and CD8+ IL-4+ cell percentages were significantly higher, and the Th1/Th2 and Tc1/Tc2 cell ratios were significantly lower, than those in the control.

CONCLUSIONS

Th2/Tc2 dominance was found in the general circulation of RSA women; this finding provokes a new controversy on the Th1/Th2 balance concerning RSA etiology.