The immunologic problem of pregnancy

Paul Russell: the transcendentalist surgeon of America

I first met Dr. Russell in the Fall of 2000 at the Massachusetts General Hospital (MGH). I entered the Russell-Round-Room which was packed with surgeons and physicians of MGH, among whom there was no shortage of self-esteem. I came across a handsome man, full of vigor and competence, standing still for nearly two hours in the corner of the room near the blackboard. He was remarkably attentive to the questions, for which he had very concise responses. He was soft-spoken with an inviting smile, and had a welcoming, modest air about him. Despite his remarkable academic achievements, he was strikingly unassuming and serene -- features likely ingrained in his very nature.

Survival of mouse ovarian tissue transplanted into the uterine horn of post-partum rats nursing pups of various numbers and sizes

Aim and background:  To investigate the effect of the number of pups being nursed on the survival of mouse ovarian tissue transplanted into the post-partum rat uterus. Methods:  Mouse ovarian tissue was transplanted into the uterine horn of post-partum rats. The number of pups nursed by each recipient rat was adjusted in a manner predetermined. Examinations were undertaken at 1-11 weeks after transplantation. Ovarian tissue containing healthy follicles was considered to have taken successfully. Results:  In rats with 12 pups, ovarian tissue remained viable at 11 weeks post-transplantation. No viable ovarian tissue remained when there were one or two pups. Viability improved as the number of pups increased. Conclusion:  When mouse ovarian tissue is transplanted into post-partum lactating rats, viability improves as the number of pups increases. We concluded that these findings may be explained in terms of progesterone levels in the recipient rats. (Reprod Med Biol 2005; 4: 149-152).

Fetal allograft survival in immunocompetent recipients is age dependent and organ specific

This study explores whether fetal allograft survival is age dependent and organ specific. Fetal rat tissue (renal, gonadal, hepatic) from the third trimester of gestation (days 15-21) was transplanted into 306 outbred adult rats for 10-30 days. Grafts were studied by morphometric and histologic analysis. Ten days after implantation, renal tissue (N = 75) from late gestation (days 19-21) showed no increase in size. In contrast, 17-day fetal grafts (N = 20) grew 6.8 +/- 3.4 times,* while 15-day fetal grafts (N = 28) grew 17.5 +/- 6.1* times. (The symbol "*" indicates p less than 0.05, compared to original size). Twenty days after implantation, these 15-day fetal grafts (N = 20) grew 48.8 +/- 17.7* times. Ten days after grafting, the younger fetal tissue showed excellent maturation of renal elements and no sign of rejection; older fetal grafts had poor renal architecture and a dense lymphocytic infiltrate. The 15-day fetal gonadal tissue (N = 18) showed a moderate 10.6 +/- 3.2* increase in size while the 15-day hepatic grafts (N = 16) were regularly rejected within 10 days. Selected fetal allografts from early in the third trimester can not only survive but can grow and mature in an immunocompetent recipient. This fetal graft growth appears to be both age dependent and organ specific. The use of fetal organs may broaden the potential pool for transplantation. However, further studies are needed to define the ontogeny of graft acceptance.

Existence of suppressor cells in the spleen of allogeneic and syngeneic primiparous pregnant mice

Mixed lymphocyte reaction (MLR) and in vitro induction of cytolytic cells against alloantigens were investigated using spleen cells from primiparous mice mated allogeneically or syngeneically. One-way MLR was reduced significantly in degree not only in allogeneic but also in syngeneic pregnant mice. MLR of virgin spleen cells was suppressed when mitomycin C-treated spleen cells taken from syngeneic or allogeneic pregnant mice were added as regulator cells. These suppressive effects disappeared when regulator cells were treated with anti-Thy 1 or anti-Lyt 2 serum plus complement. Generation of cytotoxic lymphocytes from syngeneic or allogeneic pregnancy spleen cells in MLR was depressed compared with that from virgin spleen cells. The addition of pregnancy spleen cells to MLR suppressed in vitro generation of cytotoxic lymphocytes from virgin spleen cells. These results indicated that reduction of in vitro cellular responses of pregnancy spleen cells was due to suppressor cells in the spleens. These cells suppressed non-specifically the reactions to alloantigens and could be detected both in allogeneic and syngeneic primiparous pregnancies.

Immunoglobulins and beta-1-C globulin in hydatidiform mole vesicles

Qualitative and quantitative determinations of immunoglobulins (Ig's) and beta-1-C globulin were carried out in fluid vesicles of hydatidiform moles and carrier mothers. The mean concentration of IgG was 9.9 per cent, IgA had 14.3 per cent, in relation to maternal values. No IgM concentrations were detected in molar fluid. Beta-1-C globulin showed 60.5 per cent concentration in relation to mother's serum. It is suggested that in trophoblast of molar vesicles a selective transudate migration of Ig's by a mechanism of pinocytosis takes place to the vesicular fluid.

Immunologic aspects of term pregnancy toxemia. A study of immunoglobins and complement

IgA, IgG, and IgM were measured by the single radial immunodiffusion method in umbilical cord and maternal sera in toxemia patients and in normal term pregnant cases. Complement (C' 3) levels were determined only in maternal sera. Quantitation of IgA, IgG, and IgM was performed in concentrated serial urine samples from three eclamptic and three normal control patients. Results show that there are lower IgG and IgM levels in the sera of mothers with toxemia of pregnancy; however, paradoxically higher IgM levels were detected in cord sera from their newborn infants without evidence of placental leakage or increased neonatal infection. The finding of the low IgG and IgM levels appears to be due in part to immunoglobin loss into the urine. The unchanged complement levels in toxemia, in this study, are not suggestive of an active immunologic process, but the high IgM in the newborn infants of toxemic mothers is unexplained and may represent active immunologic disease. Clearly, investigations of tissue binding and the formation of immunoglobin complexes should be carried out to better explain these abnormal findings.