Does Neospora caninum cause reproductive problems in pigs?

Neospora caninum is known to cause reproductive disturbances in several animal species, such as cattle, sheep, and goats. However, research on the effects of N. caninum on reproduction in pigs is limited. The objective of this study was to verify the transplacental transmission of N. caninum in pigs during several gestational stages. Twelve healthy Toxoplasma gondii and N. caninum seronegative female pigs were selected and separated into four groups of three animals each. Group A was maintained as a control group. Groups B, C, and D were inoculated intravenously with 2.9 × 107 tachyzoites of the N. caninum strain Nc1, 30 days before conception and at 45 and 90 days of gestation, respectively. Blood samples were collected from females periodically through IFAT for IgG and IgM screening to confirm the infection. At birth, after blood samples were collected from the piglets, they were then euthanized for the collection of the brain, heart, lung, liver, and diaphragm, which were then subjected to PCR. All inoculated gilts seroconverted (IgG) from the seventh day after inoculation. Nine of the 12 females expelled 24 mummified fetuses at the time of delivery, two in group A (eight), two in group B (four), three in group C (nine), and two in group D (three). Of the 24 mummified fetuses, nine were positive for N. caninum (one (25%) fetus of group B, seven (77.8%) of group C, and one (33.3%) of group D). A total of 126 live piglets were born. When the organs of the piglets from the inoculated females were analyzed by PCR for N. caninum, 88 (93.61%) were positive. All gilts inoculated produced at least one positive piglet. This demonstrates that there is transplacental transmission of N. caninum in all phases of gestation, regardless of the time of infection.

Colostrum and amniotic fluid from different species exhibit similar immunomodulating effects in bacterium-stimulated dendritic cells.

The fetus and newborn are immunologically immature. Bioactive compounds in amniotic fluid (AF) and maternal milk therefore play a key role in the immunological development of the infant intestine. We hypothesized that colostrum and AF exert similar immunomodulatory effects on the developing immune system. Hence, bone marrow-derived murine dendritic cells (BMDCs) were co-incubated with Clostridium perfringens A or Escherichia coli Nissle 1917 and porcine, bovine, or human AF, colostrum/milk whey fractions. Interleukin (IL) 10, IL-12, IL-6, and tumor necrosis factor-? (TNF-?) production was measured. IL-12 production was reduced with all AFs and wheys, and IL-6 and TNF-? were also reduced by porcine AF. Porcine and bovine whey both reduced TNF-? production. Overall, the reductions were most pronounced with the porcine fluids. Only bovine fluids caused strong induction of IL-10. Overall, effects of AF and whey from same species were similar. Viability of stimulated BMDCs was not significantly affected by the fluids. Neutralization of IL-10, transforming growth factor ?, and epidermal growth factor (EGF) did not remove the IL-12-inhibiting effect, but EGF neutralization increased IL-10 production. Addition of EFG to DCs enhanced the bacterium-induced cytokine production contrary to the effect of AF and colostrums, ruling out EGF as the inhibitory component in the fluids.

Perinatal period cytokines related to increased risk of future allergy development.

Testing of cytokine levels in colostrum, cord blood and amniotic fluid of healthy and allergic mothers and their newborns (using protein microarrays and quantitative analysis by ELISA) revealed differences in the levels of IL-5, IL-10, TGF-beta, TNF-alpha, EGF and eotaxin between healthy and allergic groups. Significantly higher concentration of IL-5 and IL-10 in the colostrum of allergic mothers and cord blood of their children and also tendency to a higher level of IL-4 found at allergic mothers and their children (but without statistical significance) indicate a bias to T(H)2 response in this group. The higher level of TGF-beta in the colostrum of healthy mothers should be involved in beneficial immunological tuning of their children including enhanced IgA formation and better intestine maturation. In amniotic fluid, concentration of TGF-beta was higher in children of allergic mothers. A significantly higher level of EGF was proved in the colostrum of healthy mothers and in cord blood of their children in comparison with allergic group. EGF deficiency in the allergic group could impair or delay intestine maturation and support thus allergy development.

Role of TNF-alpha in prenatal alterations in dams of mice under thermal stress.

The possible involvement of cytokines such as tumour necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta) and interferon-gamma (IFN-gamma) that are suspected of causing pregnancy loss and miscarriage has been investigated in dams of mice subjected to hyperthermia. Thermal stress was induced by exposing mice dams at 40+/-2 degrees C for 4 h every day during the different phases of the gestation period whereas the normothermic animals were housed at 22+/-2 degrees C. The effect of maternal thermal stress was measured in pregnant mice at different phases of the gestation period namely, blastogenesis-implantation phase (days 0-5 postconceptionem [p.c.]), organogenesis or embryogenesis phase (days 6-15 p.c.) and fetogenesis phase (days 16-20 p.c.). Uterine examination of dams subjected to hyperthermia on days 6-15 p.c. showed maximum reduction in live fetus number, gestational index and maximum pre and postimplantation loss in comparison with dams housed in normothermic environment and dams exposed to thermal stress between days 0-5 and 16-20 p.c. Maximum resorption rate and number of non-viable fetuses were observed in dams exposed to hyperthermia during days 6-15 p.c. Elevated levels of TNF-alpha and IL-1 beta were observed in the amniotic fluid of dams subjected to hyperthermia during days 6-15 p.c. but IFN-gamma levels remained unaltered. Single intraperitoneal (i.p.) administration of recombinant mouse TNF-alpha at a dose of 1 and 0.5 ng/mice in dams on day 6 in normothermic condition resulted in a reduced number of live fetuses. Administration of anti-TNF-alpha antibody i.p. at a dose of 10 microg/dam on day 6 p.c. and subjected to thermal stress between days 6-15 p.c. increased marginally the number of fetuses but failed to attain statistical significance in comparison with days 6-15 p.c. thermally stressed dams without antibody treatment. It is concluded that the induction of TNF-alpha, in the amniotic fluid is associated with thermal stress during pregnancy and may be linked to the reproductive performances of dams. This study will help in understanding the mechanism of thermal injury in pregnant subjects.

Concentration of anti-D antibodies in Rh(D) alloimmunized pregnant women, as a predictor of anemia and/or hyperbilirubinemia in their newborn infants.

OBJECTIVES: To define a simple, safe and reliable program for the monitoring of anti-D alloimmunized pregnancies by analysis of the covariation between antenatal values of the titer and the concentration of anti-D antibodies in maternal serum, the deltaOD(450 nm) in amniotic fluid samples, and the levels of B-hemoglobin and S-bilirubin in the newborns at birth. SUBJECTS: Ninety-three Rh(D) negative women with anti-D antibody titers > or = 16 who, after the completed 34th gestational week, gave birth to Rh(D) positive babies with a positive direct antiglobulin test. METHODS: The titers and the concentrations of anti-D antibodies in maternal serum were determined by standard procedures every second week from the 25th week of gestation. In 47 of the 93 women, deltaOD(450 nm) in amniotic fluid was determined at least once. All antenatal values used in the study were determined within 14 days before delivery. RESULTS AND CONCLUSION: Maternal serum antibody titers < or = 32 or > or = 1000 could in themselves well predict unaffected and affected newborns. Antibody titers between 64 and 512 could not accurately predict newborns with or without hemolytic disease. As a complementary monitoring test, determination of the deltaOD(450 nm) was found to be less accurate when compared to determination of the concentration of anti-D antibodies. In order to monitor Rh(D) alloimmunized pregnancies, determination of the concentration of anti-D antibodies may possibly replace determination of deltaOD(450 nm).

Soluble CD46 (membrane cofactor protein, MCP) in human reproductive tract fluids.

CD46 (membrane cofactor protein, MCP) is a cell surface complement regulatory protein which may have an additional role in human sperm-egg interaction. A soluble form (sCD46) has also been detected in a number of biological fluids, most notably seminal plasma. The present study has employed a monoclonal antibody-based ELISA to assay sCD46 in reproductive tract fluids in normal and pathological conditions. Large amounts of sCD46 were detected in seminal plasma of both fertile and infertile men (combined mean, 4859 ng/ml). Vasectomized men had lower levels (mean, 2421 ng/ml), indicating contributory sources both before and after the vas deferens ligation site. Pre-colostrum also contained relatively high quantities (mean, 445 ng/ml), whereas breast milk (mean, 117 ng/ml), peritoneal fluid (mean, 154 ng/ml) and follicular fluid (mean, 107 ng/ml), as well as uterine (mean, 208 ng/ml), umbilical (mean, 166 ng/ml) and peripheral (mean, 206 ng/ml) blood plasma, had sCD46 levels within a comparable range. Amniotic fluid had low sCD46 concentrations (mean, 22 ng/ml). In endometriosis, peritoneal fluid levels of sCD46 were significantly raised (mean, 199 mg/ml). These results indicate distinctive fluid compartmentalisation of sCD46 consistent with a biological function in human reproductive tract fluids.

Evaluation of standard parameters to predict exchange transfusions in the erythroblastotic newborn.

During the time period 1983-90, 91,300 consecutive pregnancies were monitored for red cell alloimmunization. Once revealed, the immunizations were followed by means of repeated maternal antibody titers, maternal anti-D quantitation in D-immunized women, amniotic fluid bilirubin levels and fetal hemoglobin concentrations. High dose intravenous immunoglobulin and/or intrauterine intravascular transfusion was given to prevent or treat fetal anemia. Delivery was induced for all before term when antibody titers were > or = 16. Nevertheless, exchange transfusions were performed in 41 newborns with mothers alloimmunized to Rh(D), Rh(c), Rh(E) and Kell antigens. Eight of the mothers were Rh(D) positive. Phototherapy alone was given to 35 newborns. Both maternal antibody titers and amniotic fluid bilirubin levels were found to be unreliable to predict the need of exchange transfusions in the newborns. Quantitation of maternal anti-D concentration was found to be significantly better predicting 62% at a cut-off level of 0.7 microgram/mL. Analysis of fetal hemoglobin concentration by cordocentesis is the only direct method to evaluate the degree of fetal affection, and should probably be performed when maternal antibody titers are > or = 64, anti-D concentration is > or = 0.7 microgram/mL and data indicate an aggravation of the immunization.

Inorganic phosphorus and zinc concentrations in amniotic fluid: correlation with intra-amniotic infection and bacterial inhibitory activity.

Concentrations of zinc and inorganic phosphorus were determined in amniotic fluid from 41 patients with intra-amniotic infection and from 40 uninfected, control patients. Also determined was amniotic fluid inhibitory activity to an Escherichia coli test organism. Compared to amniotic fluid from control patients, that from patients with intra-amniotic infection had significantly higher mean concentrations of phosphorus. In specimens free of meconium, the mean concentrations of phosphorus were still significantly higher. Assays for inhibitory activity were performed with 62 samples of fluid (25 noninhibitory, 37 inhibitory). Although noninhibitory fluid had higher mean concentrations of phosphorus and zinc, these differences did not hold after meconium-stained samples were excluded. No correlation was found between phosphorus-to-zinc ratio and either intra-amniotic infection or inhibitory activity. However, there are important differences in population and techniques between this and related studies.

Human immunoglobulin D in colostrum, saliva and amniotic fluid.

An antiserum raised to a partially purified preparation of secretory IgA isolated from human colostrum was shown to contain antibodies directed against human IgD. The inferred presence of IgD in the human colostrum was confirmed and also its association with antibody activity, as demonstrated by the presence of anti-E. coli antibodies. IgD was also shown to be present in whole saliva, parotid saliva and amniotic fluid, but could not be detected in jejunal juice.

Hepatitis B (surface) antigen in mothers and their infants.

Hepatitis B (surface) antigen (HBSAg) was found in the serum of 8 out of 4 245 women attending the antenatal clinic of the Queen Victoria Maternity Hospital Seven (0, 16%) were asymptomatic carriers of the antigen, while the eigth suffered from polyarteritis nodosa. Seven of the 8 babies born to these mothers were followed-up over periods of up to 18 months, and 1 has become a chronic carrier of HBSAg. The antigen was not detected in the colostrum (breast milk) of the 6 positive mothers tested, but it was present in amniotic fluid, placenta and cord blood of some of the mother-infant couples. The possible routes of transmission of the hepatitis B virus from mother to baby are discussed in the light of these findings. No cases of acute virus B hepatitis occurred in the latter months of pregnancy nor in the puerperium, among 4 088 women delivered at the hospital during this period.

Feline immunoglobulins.

Immunoglobulins (Ig) in feline sera and secretions were identified by immuno-electrophoresis and immunodiffusion with rabbit antisera prepared to feline IgG, IgA, IgM, and whole serum. Adult cat sera, colostral whey, postcolostral sera, tears, and nasal secretions contained IgG, IgA, and IgM. IgG was the only Ig identified in precolostral sera and cerebrospinal fluid. Milk, intestinal contents, pooled allantoic and amniotic fluids, and saliva from adult cats and urine from suckling kittens contained IgG and IgA. Ig were not detected in urine from adult cats. Bile was unique in that IgA and IgM were the predominant Ig.