Issue: Vojnosanit Pregl 2016; Vol. 73 (No. 4)
The structure of immunocompetent decidual cells in recurrent missed abortions
Authors:
Dragana Radović Janošević, Jasmina Popović, Miljan Krstić, Aleksandra Tubić Pavlović, Milan Stefanović, Sonja Pop-Trajković
AbstractBackground/Aim. Recurrent or habitual missed abortions
(RMA) are defined as three or more consecutive abortions. In the
first trimester of pregnancy habitual missed abortions occur in
about 1% of population. The aim of this immuno-histochemical
study of decidua in RMA of unknown etiology was to identify
subpopulations of decidual lymphocytes in recurrent miscarriages
and compare the distribution of immunocompetent cells in artificial
abortions and RMA. Methods. The study included 30 women
with at least 2 consecutive miscarriages in the first trimester of
pregnancy. Curettements of the third missed abortion were immunohistochemically
analyzed. The control group consisted of 20
women without loaded reproductive anamnesis, with the abortion
for social reasons. Criteria for exclusion from the study were diagnosed
uterine anomalies, positive screening for thrombophilia and
women who suffered from diabetes mellitus and disorders in the
function of the thyroid gland. Immunophenotyping was performed
by immuno-alkaline phosphatase (APAAP) using monoclonal
antibodies: CD 30, CD 45 RO, CD 56 and CD 57, CD 68.
Results. The number of missed abortions (1,223) was on the average
9.7% of all deliveriies during the test period. Among them
RMA were registered in 52 (4.2%) patients and in 30 (57%) the exact
etiology of abortions was not determined. RMA was most
common in the 25–34 years of age group. The largest number of
RMA showed the ultrasound characteristics of missed abortion in
60% of cases and was in nulliparous patients (76.7%). The number
of natural killer (NK) CD56 positive cells did not differ significantly
between the types of abortion. In the decidual tissue, a number of
NK CD57 positive cells was significantly higher in missed abortions
compared to artificial interruptions (p < 0.01). In artificial termination
of pregnancy there was an absolute predominance of CD45RO
lymphocyte subpopulations, whereas in the RMA group there was
slightly greater predominance of CD30 positive cells. The completed
analysis showed a significantly higher number of CD68 positive
macrophages in a decidual tissue of RMA pregnancy (p < 0.01).
Conclusion. The number and phenotypic structure of NK cells are
significantly different in normal pregnancy decidua and in RMA.
The NK cell dominance is present in the RMA group, in favor of
CD56+ and CD 57 of subpopulations with increased CD30 of T
lymphocyte subpopulations. Macrophages are more numerous in
the decidua of pregnancies ended in abortion, so the cause of RMA
of unknown etiology in a number of cases could be disregulation of
immunocompetent cells.
Key words:
abortion, habitual; immunohistochemistry; uterus; killer
cells, natural; abortion, missed; decidua.