Preeclampsia before fetal viability in women with primary antiphospholipid syndrome- materno-fetal outcomes in a series of 7 cases.

INTRODUCTION: Preeclampsia complicates about 10-17 % of pregnancies with antiphospholipid syndrome (APS). It is often severe and might occur sometimes at early gestation. The development of preeclampsia before fetal viability is a huge challenge for obstetricians and demands an intensive discussion regarding the therapeutical options. PATIENTS AND METHODS: We retrospectively reviewed the data of 7 women with primary APS who developed preeclampsia before 24 weeks of gestation. Plasma exchange had been performed in four of the cases and two women received corticosteroids. One of the women had received 20 mg of pravastatin daily, starting at 18 weeks of gestation. Neonatal outcome was: live birth in four cases and IUFD in three cases. The main pediatric complications were noted in a 28-week-old premature born boy, who developed severe IRDS and thrombocytopenia. At the present time, the boy continues to have a retarded status. DISCUSSION: This retrospective analysis revealed that women with APS can develop severe preeclampsia even before 20 weeks of gestation. Several management options for prolongation of pregnancy such as plasma exchange, pravastatin, LMHW, hydroxychloroquine/HCQ, or TNF-alpha blocker should be discussed with the patients. Optimal management of preeclampsia before 24 weeks of gestation usually depends on weighing the maternal and fetal complications from expectant management with prolongation of pregnancy versus the predominant fetal and neonatal risks of extreme prematurity from "aggressive" management with immediate delivery.

Immunoregulation of fetal and anti-paternal immune responses.

Immunological tolerance to the fetus is essential for fetal survival during pregnancy. The semi-allogeneic fetus expresses genes foreign to the mother that can be recognized by maternal T cells. Under times of stress or infection, deleterious immune responses can result in fetal destruction and/or maternal death. Exposure to non-maternal antigens begins as early as insemination and some of the mechanisms required to prevent maternal priming against these antigens are in place before sexual encounter. Continuous and overlapping regulatory mechanisms must cooperate to allow the best chances for fertilization, implantation, and healthy gestation, simultaneously protecting the fetus from maternal immune attack yet making minimal compromises in resistance to infection. Several types of immune cell from both the innate and adaptive arms of the immune system help protect both the mother and fetus during pregnancy. It's the intricate communication and interplay between the immune system and the endocrine system that will ultimately decide the success or fate of the developing fetus.

Adoptive transfer of paternal antigen-hyporesponsive T cells induces maternal tolerance to the allogeneic fetus in abortion-prone matings.

The embryo expresses paternal Ags foreign to the mother and therefore has been viewed as an allograft. It has been shown that anergic T cells generated by blocking of the CD28/B7 costimulatory pathway with anti B7-1 and anti B7-2 mAbs can be transferred as suppresser cells to prevent allograft rejection. Little is known, however, about the in vivo function of anti-B7-treated T cells after their transfer into abortion-prone mice in the maintenance of materno-fetal tolerance. In the present study, abortion-prone CBA/J females mated with DBA/2 males were administered anti-B7-1 and anti-B7-2 mAbs on day 4 of gestation (murine implantation window). The anti-B7-treated T cells subsequently were adoptively transferred into abortion-prone CBA/J mice. We demonstrated that costimulation blockade with anti-B7 mAbs at the time of implantation resulted in altered allogeneic T cell response and overcame increased maternal rejection to the fetus in the CBA/JxDBA/2 system. The transferred anti-B7-treated T cells appeared to be regulatory, decreasing responsiveness and generating clonal deviation in maternal recipient T cells. The transferred CFSE-labeled T cells were found to reside in the spleen and uterine draining lymph nodes, and a few were localized to the materno-fetal interface of the maternal recipient. Our findings suggest that the anti-B7-treated T cells not only function as potent suppresser cells, but also exert an immunoregulatory effect on the maternal recipient T cells, which cosuppresses maternal rejection to the fetus. This procedure might be considered potentially useful for fetal survival when used as an immunotherapy for human recurrent spontaneous abortion.

Preferential survival of mice expressing the Qa-2 antigen.

The Ped gene, a gene that influences the rate of embryonic cleavage division, birth weight, litter size and weaning weight, is at least partially encoded by gene(s) that specify the Qa-2 antigen. Two congenic strains of mice, B6.K1 (Qa-2 negative) and B6.K2 (Qa-2 positive), which differ only at the Q region of the mouse major histocompatibility complex (MHC), were tested for the effect of the presence or absence of Qa-2 antigen on litter size, duration of gestation and embryo survival. It was confirmed that B6.K1 (Qa-2 negative) mice have smaller litters than do B6.K2 (Qa-2 positive) mice. In addition, the duration of gestation for the B6.K1 mice was found to be longer than the duration of gestation for the B6.K2 mice. Finally, a comparison of the relative survival of Qa-2-positive and Qa-2-negative mice in a single uterine environment showed the preferential survival of mice expressing the Qa-2 antigen. Thus, the presence of Qa-2 antigen appears to be advantageous for reproductive success.