Large granular lymphocytes (LGLS) activity in women with spontaneous abortions during the 1st trimester of gestation.

BACKGROUND

Despite increasing knowledge about the cell subsets that exist in the decidua in normal early pregnancy, little is known about the decidual cell subsets in women with spontaneous pregnancy failure. Decidual large granular lymphocytes (LGLs) are the most abundant lymphoid cell type found in 1st trimester maternal decidua. The function of LGLs remains controversial although freshly isolated LGLs have been shown to exert a weak natural killer cell (NK) activity.

METHODS

Decidual leukocytes were investigated in 15 cases of spontaneous abortion and 15 cases of voluntary miscarriage, at 8th, 10th and 12th gestational week using a panel of monoclonal antibodies against Granzyme B (GRAN-B), CD2, CD38, CD56, and CD57 antigens and the immunoperoxidase technique. LGLs were demonstrated with the phloxine-tartazine stain.

RESULTS

There was a statistically significant increase in the number of CD56 and CD57 positive cells (33.3%) to the advantage of spontaneous abortions (p<0.0001). No statistically significant difference was found in the number of GRAN-B, CD2 and CD38 positive cells in normal early pregnancy and in spontaneous abortion (overall gestational age p=0.22, 8th gestational week p=0.18, 10th and 12th gestational week, p=0.091).

CONCLUSIONS

Our findings confirm previous studies referring that LGLs may have a cytotoxic activity similar to the NK activity and suggest an adverse pregnancy outcome.