HLA-A2 class I antigens in couples with recurrent spontaneous abortions.

Class I human leukocyte antigen (HLA) antigens, locus A and B, were typed in fertile and infertile couples in cases where one of the spouses carried the HLA-A2 antigen. HLA-class I typing data were obtained from 282 participants, 63 fertile couples and 78 infertile couples with recurrent spontaneous abortions (RSA). Locus A antigens were grouped into eight broad specificities (A1, A2, A3, A9, A10, A11, A19, A28) and locus B antigens were grouped, according to HLA epitopes, in two classes (BW4 and BW6). Although the number of cases is small, significant differences in the distribution of locus A antigens were found between HLA-A2-positive (A2+) women from fertile and infertile couples. HLA-A3, A11 and A28 cross-reacting antigens were absent in women from fertile couples and present in women from infertile couples. HLA-A19, which is associated with amino acid triplets of low immunogenicity, was significantly more often observed in A2+ fertile than in infertile women. An excess of the BW4 epitope was found in A2(-) husbands from infertile couples compared to fertile ones. The results of this study support the idea that in the presence of the HLA-A2 molecule the distribution of HLA-A and B loci antigens may be different in fertile couples compared to couples with recurrent spontaneous abortions. It can be suggested that the HLA-A2 molecule, in context with specific genotypes, may contribute to the overall maternal immune response in normal and disturbed pregnancy.

CD14 receptor expression and lipopolysaccharide-induced cytokine production in preterm and term neonates.

CD14 expression and the capacity of mononuclear cells (MC) from preterm and term neonates to secrete the proinflammatory cytokines interleukin (IL) 1 beta, tumor necrosis factor alpha and IL-6 in response to lipopolysaccharide (LPS) was investigated and compared to that of adults. MC were incubated with various doses of LPS, and the cytokine level in the supernatants was tested. CD14 receptors on MC and the intensity of their expression were analyzed. MC of preterm and term neonates and adults responded to LPS with low, medium and high proinflammatory cytokine production, respectively. CD14 expression was lowest in preterm infants, intermediate in term infants and highest in adults. The difference between term and preterm neonates for both parameters was significant. The results suggest a possible correlation between the lower expression of CD14 receptor on neonatal cells and the reduced secretion of proinflammatory cytokines by these cells. This decreased production may possibly contribute to the low ability of neonates to develop fever.

In vitro modulation of activation antigens on human lymphocytes by beta-estradiol.

PROBLEM: The possible in vitro immunomodulating effect of beta-estradiol on phytohemagglutinin-stimulated human lymphocyte cultures was studied. METHOD OF STUDY: Lymphocyte cultures from 12 healthy men and women aged 25-35 years were set up for 12 hr in the presence and in the absence of beta-estradiol, and the expression of the activation markers CD25, CD69, and CD71 was examined by flow cytometric analysis with specific fluorescent conjugated antibodies. RESULTS: Although the number of cases is small, in 10 of 12 cases in the presence of beta-estradiol in two different concentrations, a significantly decreased expression of CD69 could be observed. A slight decrease could also be observed for the Interleukin-2 receptor expression; however, the difference, in the presence or absence of beta-estradiol, was not significant. CONCLUSIONS: The results suggest that in vitro addition of beta-estradiol can inhibit, to a certain degree, specific activation markers on phytohemagglutinin-stimulated lymphocytes from young men and women. The present study could not define the role of sex differences because of the small number of samples. A comparison between men and women at various ages in a greater number of cases, as well as studies on activation markers after treatments with estrogens, would be useful.

Possible sex-correlated transmission of maternal class I HLA haplotypes.

Forty-seven alleles of class I HLA-AB loci (14 for locus A and 33 for locus B) were identified in 787 participants in two groups of unrelated families. Group I included parents and children typed for bone marrow transplantation. Group II included families typed for renal transplantation. Before statistical evaluation, the A locus alleles were grouped into eight classes according to broad specificity, and the B locus alleles were grouped according to HLA epitopes into two classes. Significant differences in HLA-AB haplotype frequencies were found between male and female offspring. When families with children of both sexes were analysed, the frequencies of maternally inherited HLA-AB haplotypes were found to be significantly different in brothers and sisters. The results suggest the possibility that the transmission of specific AB haplotypes from mother to offspring may be correlated to children's sex. The major histocompatibility complex has been shown to be involved in the expression of H-Y male-specific minor histocompatibility antigens. The possible selection in the transmission of specific maternal HLA-AB haplotypes to male offspring may contribute to the avoidance of maternal cytotoxic reactions toward the male foetus.

Mixed maternal-paternal lymphocyte cultures before and after immunotherapy for recurrent spontaneous abortions.

PROBLEM: The increased reactivity of maternal lymphocytes in reciprocal mixed-maternal-paternal lymphocyte cultures (MMPLC), observed in the presence of control serum after immunotherapy, suggests that immunization with paternal lymphocytes may induce a highly significant cell mediated immune response in specifically alloactivated maternal lymphocytes. METHOD: Reciprocal one-way MMPLC were set up with responding maternal or paternal lymphocytes and mitomycin C-treated stimulating lymphocytes. Cultures were set up for 6 days in the presence of 15% maternal or control serum. The degree of lymphocyte stimulation was measured by tritiated thymidine uptake. RESULTS: In maternal serum, after immunotherapy, a highly significant blocking effect on MMPLC was observed in both directions. The extent of the blocking effect in maternal serum and the stimulation in control serum was much higher, after immunotherapy, in two cases of abortions, as compared to cases with normal pregnancy outcome. CONCLUSIONS: Although the number of cases is very small, it may be that in abortions, in the presence of maternal serum, disturbances in the balance of cytokines or/and specific antibodies could have cytotoxic effects on MMPLC and down regulate, or "block" the specific response. For a possibly better utilization of the MMPLC test in the prediction of pregnancy outcome after immunotherapy, it may be important to examine specific antibodies in maternal serum, to investigate specifically induced cytokines in MMPLC and to evaluate T cell subsets in MMPLC in the presence of maternal and control serum.

Contribution of class I HLA-A2 antigen in immune reactions.

The involvement of the Class I HLA-A2 antigen is briefly reviewed in relation to allograft rejection, the feto-maternal relationship, viral cytotoxic reactions and tumor immunity. It is suggested that the HLA-A2 molecule may have, as compared to other HLA Class I alleles, a dominant role as a restricting element in cytotoxic T-cell recognition in the feto-maternal relationship to male fetuses, in specific viral infections and in tumors. As compared to other HLA Class I alleles, its reduced expression or loss in a variety of tumors suggests its possible important role in tumor immune surveillance. The disappearance of HLA-A2 from tumor cells may eventually contribute to the escape from T-cell recognition of malignant cells.

IN vitro cell-mediated immune reactions in herpes zoster patients treated with cimetidine.

In a double-blind placebo-control study the immunomodulating effect of cimetidine treatment for one week and placebo was investigated for cell-mediated immune reactions of 22 patients with herpes zoster (HZ). The mitogen induced leukocyte migration inhibition test (LMIT) and the in vitro proliferation of the patients' lymphocytes to exogenous IL-2 were used. Before any treatment, the mitogen induced leukocyte migration inhibition capacity (LMIC) of HZ patients was found to be significantly reduced (p < 0.02) as compared to healthy blood bank donors (controls). After one week, within the same treatment, the LMIC was significantly improved (p < 0.01). The patients' lymphoproliferative response to IL-2, before any treatment, was not significantly different from that of controls (p < 0.05). However, significantly higher values (p < 0.001) were found in patients tested 7 days after the disease onset as compared to those tested after 12 days. One-week cimetidine treatment significantly improved (p < 0.05) the lymphoproliferative response to IL-2 of initially low responders and had no effect on higher responder patients. In contrast to this, after one week of placebo treatment, a significant decrease in the patients' lymphoproliferative response to IL-2 could be observed as compared to patients' initial responses (p < 0.05) or to those of controls (p < 0.05). Although the number of cases is very small. The data suggest that after cimetidine treatment, as compared to placebo, healing from skin rash and pain was achieved in a significantly shorter time (p < 0.01).

Distortion in the parental transmission of HLA-A2 haplotypes (locus A,B).

The parental transmission of HLA-2 antigen in association with the epitopes BW4 and BW6 (class I HLA haplotypes locus A,B) was analyzed in sons and daughters from 42 families in which one of the parents carried the HLA-A2 antigen. When the parental transmission of A2 BW4 and A2 BW6 was compared, it was observed that a significantly higher number of siblings inherited the haplotype A2 BW4 from the paternal than from the maternal haplotype. Although the number of cases is small, the mode of inheritance of haplotype A2 BW6 was completely different. The genetic distortion in the transmission of HLA-2 BW4 and HLA-2 BW6 was observed in children of both sexes.

Mode of inheritance of HLA haplotypes locus A,B in siblings of different sexes.

METHOD: Forty-eight parents and 172 children were typed for class I HLA antigens, locus A,B. RESULTS: Although the number of cases is small, we observed: (1) a significantly decreased number of sons born after a first delivery of a son, as compared to a first delivery of a daughter; (2) significantly increased sharing of maternal class I HLA antigens between the firstborn son and his brothers from higher birth orders, as compared to his sisters; and (3) HLA-A2 antigen, which is known to be involved in HLA restricted cytotoxic reactions in the recognition of minor histocompatibility antigens, was inherited in subsequent deliveries of sons as compared to daughters in a significantly higher frequency from the paternal than from maternal HLA haplotype. The results suggest that sharing of identical maternal HLA haplotypes between brothers may aid to decrease the degree of maternal sensitization to fetal antigens, and lack of HLA-2 antigen in maternal cells from sons as compared to daughters may avoid maternal HLA-A2 restricted cytotoxic reactions toward the male fetus.

Sialic acid level in maternal and neonatal lymphocytes and sera correlated to birth order and sex of the neonate.

Sialic acid (N-acetylneuraminic acid) was determined 1 h after normal term deliveries on peripheral blood lymphocytes from 42 mother-neonate pairs and in 29 maternal and neonatal sera. Results were evaluated according to maternal parity and sex of the neonate. The cases were divided into two groups: primiparae, and secundi- and multiparae. In primiparae the sialic acid level on lymphocytes from male neonates and from their mothers was by 23-30% decreased as compared to female neonatal and maternal cells. In the higher parity group, a significantly increased sialic acid level was found on lymphocytes from male as compared to female neonates, and maternal serum sialic acid concentration, unrelated to the newborns' sex, was by 17-20% increased as compared to primiparae. The results suggest that with increasing parity higher levels of sialic acid on male neonatal cells may possibly contribute to mask fetal male-specific histocompatibility antigens. Increased sialic acid levels in maternal sera from secundi- and multiparae suggest its possible contribution to an increased serum blocking effect.

Expression of transferrin receptor on human maternal and neonatal peripheral blood lymphocytes.

The levels of peripheral blood lymphocytes expressing the receptor for transferrin (TSR) on untreated and phytohemagglutinin (PHA)-stimulated cell samples from maternal-neonate pairs were evaluated 4-12 h postpartum. Significantly increased levels of TSR+ cells were observed on fresh, unstimulated neonatal and maternal cells, as compared to control cells from young adult males and females, and the values seemed to correlate with the sex of the neonate and with birth order. The level of TSR+ cells in culture was found to be increased on neonatal cells and decreased on maternal cells.

The effect of serum from patients with acute myocardial infarction on in vitro lymphocyte reactivity. II. Inhibition of IL-2 production.

Culture supernatants from concanavalin-A (con-A)-activated peripheral blood lymphocytes from healthy controls grown in the presence of sera from 20 patients 24 hours and 1 week after acute myocardial infarction (AMI) were tested for their mitogenic activity and for the presence of interleukin-2 (IL-2). Binding of exogenous IL-2 to activated lymphocytes from 10 patients was also determined. In supernatants prepared in the presence of patients' as compared to control sera, a significantly decreased mitogenic activity and IL-2 content were found. The mitogenic activity and IL-2 content in culture supernatants prepared with patients' sera collected 24 hours after the AMI (AMI I) and one week thereafter (AMI II) were significantly suppressed, and the degree of suppression in the 24-hour sera was significantly higher than in those collected after one week. No significant differences were observed in the binding capacity to exogenous IL-2 of activated patients' and control lymphocytes. The possibility is that immunosuppressive factors in the patients' sera, including cortisol, may suppress the patients' immune response acting through inhibition of IL-2 production.

The effect of serum from patients with acute myocardial infarction on in vitro lymphocyte reactivity. I. Inhibition of mitogen stimulation.

Sera from 20 patients obtained within 24 hours and one week after acute myocardial infarction (AMI) were tested for their immunomodulating effect on concanavalin-A (con-A) stimulated lymphocyte cultures from 11 healthy unrelated donors. Individual control sera from 21 healthy donors and 5 pools of control sera were used for comparison. Cortisol levels were tested in patients' and controls' sera. A significantly higher suppressive effect was seen in the presence of patients' sera taken at 24 hours than corresponding sera taken one week later. However, the suppressive effect after one week was increased as compared to control sera. A significant correlation between the degree of suppression and the cortisol level in corresponding sera was observed. An increased immunosuppression was observed with increased cortisol levels.

Role of children's sex in mixed mother-child lymphocyte culture reactivity.

One-way mixed mother-child lymphocyte cultures (MMCLC) 4 to 20 years after the last delivery were studied with maternal responding and children's or fathers' stimulating cells (MMFLC) in 14 multiple child families with 18 sons and 20 daughters. HLA antigen typing locus A, B, DR was performed for all family members. As reported previously for newborn cells, a significantly increased maternal response could be observed in MMCLC with male as compared to female children's stimulating cells. Although the number of cases studied was small, it seems that the increased stimulating effect of male children's cells could also be observed when MMCLC values from children of different sex, and identical A,B,DR haplotypes were compared. In contrast to this, A,B,DR haploidentical children of the same sex seem to have a similar stimulating effect on the maternal response in MMCLC. The results suggest that male children's Y-chromosome-correlated minor histocompatibility antigens may additionally stimulate the maternal immune response in MMCLC.

Changes in maternal and newborn lymphocyte reactivity in reciprocal mixed lymphocyte cultures during the postpartum period.

Reciprocal one-way mixed mother-newborn lymphocyte cultures (MMNLC) containing alternatively maternal or newborn responding (R) or stimulating (S) cells were investigated in both directions in primiparae at three different times: a few hours after delivery, and at 4 and at 16 weeks. Cultures were grown in the presence of maternal and pooled control serum prepared from the blood of five to eight unrelated healthy donors. Four weeks after delivery in maternal and in control serum a significant increase in MMNLC reactivity could be observed, which disappeared at 16 weeks when a pronounced decline in MMNLC values in both directions was found. The suppressive effect of maternal serum was more pronounced at delivery, still evident 4 weeks later, and insignificant after 16 weeks. The results of this study suggest that 4 weeks after delivery, maternal sensitization to fetal histocompatibility antigens can be detected in primiparae with MMNLC; and that 16 weeks later, this was no longer detectable with the same test.

Thrombocytopenia associated with hypersensitivity to ranitidine: possible cross-reactivity with cimetidine.

A rare case of thrombocytopenia associated with ranitidine is described. The thrombocytopenia was accompanied by eosinophilia and slightly elevated serum IgE. The platelet and eosinophilic counts returned to normal as soon as the drug was stopped. Cell-mediated immunity (CMI) determined in vitro by the leukocyte migration inhibition factor test was found against ranitidine and cimetidine. IgE antibody response against both drugs was also found by the mast cell degranulation test. These data suggest an association between the ranitidine-induced thrombocytopenia and both humoral antibody response and CMI. Cross-reactivity between the two H2-receptor antagonists is suggested, as well.

Role of the newborn's sex in mixed maternal-newborn lymphocyte culture reactivity.

One-way-stimulated mixed mother-newborn lymphocyte cultures (MMNLC) from male and female newborns were evaluated and compared shortly after delivery. Newborn sex-correlated differences were observed in the strength of the MMNLC reactivity with responding maternal as well as newborn cells. The reactivity of MMNLC with responding maternal cells from male as compared to female newborns was significantly less inhibited in maternal and newborn serum. The inhibitory effect of maternal serum on maternal and male newborn lymphocytes in MMNLC seems to be correlated to the sex of the previous child delivered and was significantly lower when the present as well as the previous baby were of the same sex, e.g. 2 boys. The results suggest that fetal-male-specific Y-chromosome-correlated histocompatibility antigens may specifically influence the maternal immune response to her fetus.

Lymphocyte subpopulations in mother and newborn: correlation with sex of the newborn and number of pregnancies.

T cell subsets were defined with monoclonal antibodies of the OKT series, OKT3, OKT4 and OKT8, in 23 male and 22 female newborns and in their mothers 4-10 h after delivery. The data were compared and statistically evaluated between mother and newborn, between male and female newborns as well as between parity groups. The results indicate that the distribution of OKT4 and OKT8+ cells is different in mother and newborn and a significantly increased percentage of OKT4+ cells and a significantly decreased percentage of OKT3+ cells was observed in newborns as compared to their mothers after the first and second delivery. For maternal cells from male as compared to female newborns the percentage of OKT4+ was significantly decreased after the second delivery. OKT8+ cells in the mother were significantly decreased after the second as well as after three or more deliveries of male as compared to female newborns. With increasing parity the percentage of OKT3+, OKT4+ and OKT8+ cells decreased slowly for both sexes and the difference was significant between primi- and multiparae. The present findings suggest a possible role of the newborn sex and of parity in the distribution of specific T cell subsets in mother and newborn shortly after delivery.

Primary tissue cultures of benign and malignant human thyroid tumors: effect of TSH.

Many thyroid carcinomas seem to be dependent upon the thyroid growth-promoting properties of the thyroid stimulating hormone (TSH). The purpose of the present investigation was to compare the in vitro effect of TSH on tissue cultures derived from malignant and benign thyroid tumors. The results indicate that TSH can affect the morphology and protein synthesis of primary tissue cultures derived from benign and malignant thyroid tumors differently. The addition of TSH to cultures derived from benign tumors resulted in a reorganization of follicle-like structures of the monolayer and in a reduction of protein synthesis. In contrast to this, monolayers derived from carcinomas of the thyroid were not able to reorganize and their protein synthesis was not inhibited in the presence of TSH. For a better understanding of TSH suppressive therapy, we suggest testing the influence of TSH on a large number of tissue cultures derived from benign and malignant tumors of the thyroid.

Sialic acid content and sialyltransferase activity in human lymphocytes with advancing age.

Sialic acid and sialyltransferase activity were determined in lymphocytes obtained from the blood of 78 healthy male volunteers aged 20-80 years. When grouping was made in double decades, statistical evaluation using the Duncan procedure indicates that sialic acid did not show significant differences between groups, whereas the sialyltransferase activity was significantly higher in the group aged 41-60 years as compared to the group aged 20-40 years and the group aged 61-80 years, both at the 0.05 level.