Immunophenotype of peripheral T lymphocytes, NK cells and expression of CD69 activation marker in patients with recurrent spontaneous abortions, during the mid-luteal phase.

PROBLEM: Determination of subpopulations of T lymphocytes, natural killer (NK) and activation status, in peripheral blood during the mid-luteal phase from patients with unexplained recurrent spontaneous abortion (RSA). METHOD OF STUDY: Peripheral blood samples from non-pregnant women with RSA and normal multiparous were taken and evaluated for subpopulations of T lymphocytes: CD4, CD8, ('naive-like' and 'memory-like'), TCR receptor (alphabeta and gammadelta), activation status by CD69(+surface or intracellular)/CD3(+), and NK cells (CD16(+)/CD56(dim)/CD3(-), CD16(+)/CD56 (bright)/CD3(-), CD69(+surface or intracellular)/CD56(+)/CD3(-) cells). RESULTS: The evaluation of T lymphocytes only showed an increase in the expression of CD69 (surface and intracellular) in the RSA group. Additionally, we observed an increase in the total NK cells, CD56(+) NK cells percentages, CD56(dim) NK cells and CD69 NK cells in RSA group. CONCLUSION: These observations support the concept that immunological activation of T lymphocytes and NK cells could be involved in peripheral blood during the mid-luteal phase in patients with unexplained RSA.