The fetus, not the mother, elicits maternal immunologic rejection: lessons from discordant dizygotic twin placentas.

AIMS: Our objective was to elucidate the pathogenesis of twin discordance in four dizygotic pregnancies where only one of the twins had IUGR due to chronic villitis. METHODS: We identified four cases of dizygotic twin placentas over a period of four years with evidence of chronic villitis. There was no clinical or pathologic evidence of TORCH, bacterial infection, preeclampsia or autoimmune disorders. Placentas were weighed, processed for histologic examination and stained with CD45RO (clone UCHL1) mouse monoclonal antibody, which identifies T-cells. RESULTS: All placentas were dichorionic, with two being fused. Birth weight differences were 29%, 41%, 17% and 10%. Villitis was more marked in the placenta of the twin that weighed less and correlated with the degree of weight discordance. On examining the junction between the fused dichorionic placentas, the chorionic villi from the smaller twin contained numerous T-cells, whereas the villi associated with the less affected twin, showed little to no T-cells. CONCLUSION: We describe a series of dizygotic twin placentas where the more severe the chronic villitis, the more affected the placenta and fetus. Since the maternal environment was constant for each of these twins, differences in villitis severity appears to be attributable to differences in the ability of each placenta to induce a maternal immune response.

T helper 1/t helper 2 cell immunity in preeclamptic twin pregnancy.

Preeclampsia has been classified into two types on the basis of the T helper (Th)1/Th2 balance: Th1-predominant type and Th2 predominant type. In this study, we examined the Th1/Th2 ratio in peripheral Th cells in 11 patients with preeclamptic twin pregnancies, 11 normal (nonpreeclamptic) twin pregnancies, 11 preeclamptic singleton pregnancies, and 11 normal singleton pregnancies. The average Th1/Th2 ratio in the patients with preeclamptic twin pregnancy was 8.3 +/- 3.4 (mean +/- SD), which was similar to those in patients with normal singleton and twin pregnancies and significant lower than that in patients with preeclamptic singleton pregnancies (p = 0.003). The present results suggest that the mechanisms of preeclampsia differ between singleton and twin pregnancies.

Skin disease is prevented but nephritis is accelerated by multiple pregnancies in autoimmune MRL/LPR mice.

The role of pregnancy in the progression of systemic lupus erythematosus (SLE) is still poorly understood. We analysed the effect of repeated pregnancies in MRL/lpr mice, a murine model of SLE. Seven-week old female mice were used: multiparous mice underwent three consecutive pregnancies (M); age-matched virgin mice served as controls (V). Animals were harvested at 20 weeks of age. Skin lesions were characterized by hair loss and scabs in the dorsum of the neck. Virgin skins showed thickened dermis, fibrosis and mononuclear cell infiltrates, which were practically absent in M. This was accompanied by higher IFN-gamma and lower IL-10 mRNA expression levels in V compared to M skin. Plasma IFN-gamma protein levels were also upregulated in V versus M. However, survival and kidney function were dramatically reduced and accompanied by hypertension after multiple pregnancies. Kidney histology also showed markedly increased renal lesions in M. In contrast to plasma and skin levels, both IL-10 and IFN-gamma mRNA were lower in the kidneys of V versus M mice. Concluding our findings, the pathomechanisms of lupus kidney and skin disease may be regulated differently at the organ level during pregnancy. Both IFN-gamma and IL-10 may be important regulatory cytokines at the local level.

Differential expression of immune system-related components in midtrimester amniotic fluid from singleton and twin pregnancies.

OBJECTIVE: We investigated differences between singleton and twin gestations in immune mediators in midtrimester amniotic fluid. STUDY DESIGN: Amniotic fluid from 252 singleton and 46 twin gestations were tested by enzyme-linked immunosorbent assay for interleukin-1beta, interleukin-1 receptor antagonist, interleukin-4, tumor necrosis factor-alpha, nitric oxide, Clara cell protein 16, leptin, and the 70-kDa heat shock protein. A subset of amniotic fluid was also tested for leukemia inhibitory factor, angiogenin, and migration inhibitory factor-related protein 8 and migration inhibitory factor-related protein 14. Data were analyzed by the Mann-Whitney U test and Spearman rank correlation. RESULTS: Median concentrations of interleukin-1beta, tumor necrosis factor-alpha, interleukin-4, Clara cell protein 16, leptin, and angiogenin were increased in amniotic fluid from twins; median levels of the 70-kDa heat shock protein, leukemia inhibitory factor, migration inhibitory factor-related protein 8, and migration inhibitory factor-related protein 14 were highest in amniotic fluid from singletons (P < .001). CONCLUSION: Elevated levels of immune activators may contribute to the increased rate of preterm premature rupture of membranes and spontaneous preterm birth in twin populations.

Accelerated immunosenescence in preindustrial twin mothers.

Life-history theory predicts a tradeoff between reproductive effort and lifespan. It has been suggested that this tradeoff is a result of reproductive costs accelerating senescence of the immune system, leading to earlier death. Longevity costs of reproduction are suggested for some human populations, but whether high reproductive effort leads to impaired immune function is unknown. We examined how reproductive effort affected postreproductive survival and the probability of dying of an infectious disease in women born in preindustrial Finland between 1702 and 1859. We found that mothers delivering twins had reduced postreproductive survival after age 65. This effect arose because mothers of twins had a higher probability of succumbing to an infectious disease (mainly tuberculosis) than mothers delivering singletons. The risk among mothers of twins of dying of an infectious disease was further elevated if mothers had started reproducing early. In contrast, neither female postreproductive survival nor the risk of succumbing to an infectious disease was influenced by the total number of offspring produced. Our results provide evidence of a long-term survival cost of twinning in humans and indicate that the mechanism mediating this cost might have been accelerated immunosenescence.

Maternal peripheral T helper 1-type and T helper 2-type immunity in women during the first trimester of twin pregnancy.

INTRODUCTION: This study investigated the T helper Th1:Th2 balance in twin pregnancies compared with singleton pregnancies during the first trimester. METHODS: Blood samples were taken from 24 women with a singleton pregnancy and 14 women with twin pregnancy at 8-9 weeks' gestation to examine the ratios of Th1:Th2 and serum human chorionic gonadotropin (hCG) and progesterone levels. RESULTS: The average ratio of Th1:Th2 in the twin pregnancies was significantly lower than that in singleton pregnancies (7.3+/-2.3 vs. 10.5+/-2.2, p<0.05). There were negative correlations between the Th1:Th2 ratio and serum hCG levels (mIU/ml) (Th1:Th2 ratio = 14.5-4.52 x 10(-5)xhCG, r(2)=0.41, p<0.05) and between the Th1:Th2 ratio and serum progesterone levels (ng/dl; Th1:Th2 ratio = 23.0-0.63 x progesterone, r(2)=0.36, p<0.05). CONCLUSION: Our findings show marked predominance of Th2 type cytokines occurring in twin pregnancies is related to the increase in trophoblasts during the first trimester.

Relation between plasma endothelin-1 levels and T helper-1:T helper-2 immunity in women with twin pregnancies.

The aim of this study was to investigate the relationship between plasma ET-1 levels and T helper-1 (Th1):Th2 immunity in women with twin pregnancies. The percentage of Th1 and Th2 cells and the Th1:Th2 cell ratios in peripheral blood from 13 normal singleton pregnant women and 13 patients with twin pregnancies at 29-34 weeks' gestation were calculated using flow cytometry. The plasma ET-1 was also determined using a modified radioimmunoassay. The plasma ET-1 concentrations and the cell ratios of Th1:Th2 in twin pregnancies were significantly lower than those in singleton pregnancies. A positive correlation was found between plasma ET-1 levels and the ratios of Th1:Th2 cells in the whole subjects. Our results indicate that decreased ET-1 levels are associated with Th1:Th2 immunity in twin pregnancies.

Maternal peripheral T-helper 1-type and T-helper 2-type immunity in nonpreeclamptic twin pregnancies.

The percentage of T-helper (Th)1, Th2 cells and the Th1:Th2 cell ratios in peripheral blood from 14 normal nonpregnant women, 23 normal pregnant women and 9 patients with twin pregnancies without preeclampsia at 28-32 weeks' gestation were calculated using flow cytometry. In normal pregnant women, the percentage of Th1 cells and Th1:Th2 ratios were significantly lower than those in nonpregnant women. In twin pregnancies, the percentage of Th1 cells and the Th1:Th2 ratios were significantly lower than those in non-pregnancies. In twin pregnancies; in addition, the percentage of Th1 cells was significantly lower than that in singleton pregnancies. Our findings show a markedly predominant Th2 immunity in twin pregnancies.

Effects of subclinical pregnancy toxemia on immune responses in sheep.

OBJECTIVE: To determine the effects of moderate feed restriction, single or twin pregnancy, and subclinical pregnancy toxemia (PT) on immune responses of ewes. ANIMALS: 16 Sardinian ewes. PROCEDURE: Six weeks before lambing, ewes were assigned to 1 of 2 groups (n = 8/group) matched for number of fetuses, body condition score, and plasma glucose, non-esterified fatty acids (NEFA), and beta hydroxybutyrate (BHBA) concentrations, and feed intake was restricted for 1 of the groups. Cell-mediated immunity was evaluated in vivo and in vitro. Humoral immunity was evaluated in vivo by determining production of IgG antibodies against keyhole limpet hemocyanin (KLH). RESULTS: Four ewes developed subclinical PT (plasma BHBA concentration > 0.86 mmol/L without any clinical signs of disease). Whether feed was restricted and type of pregnancy (single vs twin) did not have any significant effects on cell-mediated and humoral immune responses. Ewes with subclinical PT had significantly lower in vitro proliferation of phytohemagglutinin-stimulated peripheral blood mononuclear cells and significantly lower values for KLH-specific IgG than did healthy ewes. Plasma BHBA and NEFA concentrations were negatively correlated with in vitro proliferation of peripheral blood mononuclear cells; plasma NEFA concentration was negatively correlated with values for KLH-specific IgG. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that subclinical PT may be associated with impairments in cell-mediated and humoral immune responses in sheep.

Interleukin-1alpha, interleukin-6 and interleukin-8 in cervico/vaginal secretion for screening of preterm birth in twin gestation.

BACKGROUND: The purpose was to determine the prognostic value of interleukin (IL) 1-alpha, IL-6 and IL-8 in cervico/vaginal secretion for preterm birth (<37 weeks of gestation) in twin pregnancies. METHODS: The study included screening of 121 women with twin pregnancies with sampling at 24, 26, 28, 30, 32 and 34 weeks of gestation. IL-1alpha, IL-6 and IL-8 was analyzed with ELISA immunoassays. The detection limit was 30 pg/mL for IL-1 and IL-8 and 40 pg/mL for IL-6. Vaginal fluid was smeared and dried for later evaluation of bacterial vaginosis (presence of clue cells). RESULTS: Spontaneous preterm birth occurred in 36 women and 65 women were delivered at term. IL-8 was significantly higher (p=0.03) in samples from women delivered preterm (median 3.72 ng/g mucus, range <0.07-220.00) compared with samples from women delivered at term (median 3.03 ng/g mucus, range <0.08-378.60). At 28 weeks of gestation, IL-8 (cut off 1.75 ng/g mucus) was associated with preterm delivery (relative risk 2.2, CI 95% 1.1-4.5) with a sensitivity, specificity, positive and negative predictive value of 78.8, 45.8, 44.8 and 79.4%, respectively. The levels of IL-1alpha and IL-6 were not significantly associated with preterm birth. Bacterial vaginosis was found in 47/541 (8.7%) samples analyzed. The levels of IL-1alpha and IL-8 were significantly higher in samples positive for bacterial vaginosis than in negative samples (p<0.0001 and p<0.01, respectively). There was no significant association between the level of IL-6 and bacterial vaginosis. CONCLUSIONS: IL-8, but not IL-1alpha and IL-6, was associated with preterm delivery but the relationship was too weak to be of predictive value for preterm birth in twin pregnancies. IL-1alpha and IL-8, but not IL-6, were associated with bacterial vaginosis.

[Preventive anti-D after massive fetomaternal hemorrhage]. / Anti-D-Prophylaxe nach massiver fetomaternaler Hämorrhagie.

In the 36th week of gestation intrauterine death of both twins occurred in a 31-year old primigravida. The examination of the C- and the D-antigen of the mother's blood (result of previous testing: AB Rhesus negative) immediately before delivery showed a mixed field agglutination which pointed to a fetomaternal macrotransfusion. Fetal haemoglobin in the mother's circulation was 7.8% of her total haemoglobin, so that a fetomaternal haemorrhage of about 440 ml whole blood had to be suspected. For Rhesus-prophylaxis 17 standard doses of anti-D-immunoglobulin were administered intramuscularly distributed over 4 days. No adverse effects were seen; fetal haemoglobin dropped to 2.0% 5 days and to 0.1% 15 days after the beginning of the treatment. A control examination after 9 months showed no signs of a Rhesus-(D)-sensitisation of the patient.

IL-6 and G-CSF levels in amniotic fluid during the second trimester in normal and abnormal pregnancies.

Activity levels of cytokines were measured by stimulation of the cell lines NFS-60, 7TD1, and TF-1. In 39 samples of amniotic fluid, levels of Granulocyte-Stimulating Factor (G-CSF) were 1434 +/- 2063 (mean +/- SD) and of Interleukin (IL-6) 546 +/- 1071 pg/ml; Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) was not detectable. IL-6 was correlated to G-CSF (r = 0.3; p = 0.003). G-CSF (p = 0.0002) and IL-6 (p = 0.006) were influenced by Alpha-Fetoprotein (AFP) and G-CSF by rhesus-incompatibility (p = 0.0004). These findings suggest that cytokines such as IL-6 and G-CSF play some role in physiological and pathological pregnancy.

Immunological manipulation of ovulation rate for twinning in cattle.

Unlike in sheep, in which immunization against androstenedione causes mild and reasonably controlled increased ovulation rate, in similar studies cattle showed highly variable responses ranging from increased ovulation rate and fertility through to anovulation/anoestrous or superovulation. As a consequence, interest in manipulation of ovulation rate through this approach has declined and is now focused on immunological manipulation of endogenous inhibin following successful studies in sheep. Studies have concentrated on developing a prototype inhibin-based vaccine to be used for twinning in the Australian beef industry. The prototype vaccine (with recombinant ovine inhibin-alpha.3 fusion protein and Montanide:Marcol adjuvant) has proved to be very potent and control of the degree of ovarian stimulation has not been possible. The proportion of cattle with increased ovulation rate after inhibin immunization is affected by timing of booster vaccination within the ovarian cycle, time after vaccination, vaccine formulation and possibly genotype. Physiological studies show that cattle responding to the inhibin vaccine have increased plasma inhibin binding of native bovine inhibin, high plasma FSH concentrations, greater numbers of large (> or = 8 mm) follicles and fewer small (< 5 mm) follicles during the preovulatory wave of follicular development compared with control or non-responding animals. Significant correlations among the response parameters (i.e. inhibin binding, plasma FSH concentrations, number of large follicles and ovulation rate) have been demonstrated. The results indicate that greater understanding of the various processes of folliculogenesis will be necessary to achieve a controlled increase in ovulation rate in cattle.

Prolongación exitosa de gestación gemelar de pretérmino complicada con un feto muerto y coagulación intravascular diseminada / Succesfully prolongation of twin preterm gestation complicated with one fetal death and disseminated intravascular coagulation

Se presenta un caso clínico de embarazo gemelar con coagulación intravascular diseminada y un feto muerto in utero en la semana 24, en el cual se utilizó heparina para prolongar la gestación. Se describe el uso de heparina y su efecto en el perfil hemostático de la paciente y su importancia en la resolución del caso

[Alloimmune neonatal granulocytopenia caused by anti-NA1 antibodies]. / Alloimmunologiczna granulocytopenia noworodków wywolana przeciwcialami anty-NA1.

Two cases of neonatal alloimmune granulocytopenia due to fetomaternal incompatibility with granulocyte-specific antigen NA1 are presented. The diagnosis was based on the detection of anti-NA1 alloantibodies in maternal and neonates sera in leukoaglutination and immunofluorescence tests with granulocytes. Both children (twins) had severe granulocytopenia and unfortunately died.