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.

Fetal membrane biomarker network diversity and disease functions induced by intra-amniotic pathogens.

PROBLEM: Intra-amniotic pathogens and by-products activate innate immune responses encompassing multitudes of signaling molecules and pathways that can result in spontaneous preterm birth (PTB). This study investigates fetal membrane response to bacterial stimulation using a bioinformatics approach. METHOD OF STUDY: Dysregulated biomarker (IL1-ß, IL-2, IL-8, IL-10, and TNF-α) data from fetal membranes at term stimulated with Ureaplasma urealyticum, Ureaplasma parvum, Mycoplasma hominis, E. coli, Group B Streptococci, Polyporhans gingivalis, or Gardnerella vaginalis with 50% (v/v) amniotic fluid (AF) were analyzed by Ingenuity Pathway Analysis. RESULTS: In racially stratified analysis, networks representing late-stage immune inflammation were seen in African-Americans in AF absence. Inflammation was dominant in AF presence as well. In Caucasians, late-stage immune response was dominant with AF, but not in its absence. CONCLUSIONS: Fetal membrane biofunctions in response to bacteria reflect early- and late-stage innate immune defenses that vary based on the presence of AF and subject race.

Amniotic fluid and maternal race influence responsiveness of fetal membranes to bacteria.

Spontaneous preterm birth (PTB) and preterm prelabor rupture of membranes (pPROM) occur more frequently in African-American women than in other racial groups. This may be due to an enhanced inflammatory response to pathogens associated with the condition. It is also possible that amniotic fluid (AF) has different immunomodulatory properties in African-American women that increase their risk of PTB and pPROM. To test this, we cultured fetal membranes from European-American and African-American women with sterile medium (control), Escherichia coli, Gardnerella vaginalis, Group B streptococci (GBS), Polyporphorans gingivalis, Mycoplasma hominis, Ureaplasma urealyticum or Ureaplasma parvum in the presence and absence of 50% autologous AF. Cytokine concentrations were quantified in the conditioned medium. All bacterial species increased IL-8 production. IL-1ß and TNF-α production were stimulated by LPS, E. coli, and G. vaginalis compared with control, but responses to Group B streptococci and P. gingivalis were limited to IL-1ß and TNF-α respectively. Genital mycoplasmas stimulated TNF-α and IL-10 but had no effect on IL-1ß production. African-Americans had twice the IL-1ß response to E. coli as European-Americans (P=0.031). Conversely, European-Americans produced more IL-8 in response to LPS than African-Americans (P=0.026). AF had both pro- and anti-inflammatory properties that varied between races and pathogens. These results suggest that the host response to fetal membrane infections is complex and not generalizable. Interventions to prevent PTB and pPROM may need to be customized based on a patient's race, type of bacterial infection and factors in her AF.

Periodontal disease and preterm birth.

Preterm birth (delivery at fewer than 37 weeks' gestation) is the most common cause of infant morbidity and mortality among nonanomalous infants in the United States. Increasing evidence has focused on associations between clinical infection, inflammation, and preterm birth. Maternal periodontal disease, which is associated with systemic inflammation, has been associated with preterm birth. Intervention trails for treatment of periodontal disease during pregnancy, however have not consistently shown a reduction in preterm birth rates. Despite the lack of reduction in preterm birth, oral health maintenance is an important part of preventive care and should be supported during pregnancy.

The nature of secretory agglutinins and aggregating factors. II. Biochemical and immunochemical properties of factors in human saliva and amniotic fluid.

Secretory conglutinin-like factor (SKF) and secretory bacterial aggregating factors (SBAF) of saliva and amniotic fluid were characterized as high molecular weight non-mucin glycoproteins. Most biochemical tests or procedures used in previous investigations did not permit an unequivocal distinction among immunoglobulins, non-mucin glycoprotein, or mucin factors. Partitioning with hot phenol enabled the separation of a high molecular weight non-mucin glycoprotein fraction from saliva and amniotic fluid with SKF and SBAF activity that was distinct from mucins and antibodies. Non-mucin glycoproteins, immunoglobulins and mucins represent three classes of secreted molecules capable of clumping bacteria.

The nature of secretory agglutinins and aggregating factors. IV. Complexing between non-mucin glycoproteins, immunoglobulins and mucins in human saliva and amniotic fluid.

By themselves the non-mucin glycoproteins of saliva and amniotic fluid produce secretory conglutinin-like factor (SKF) and secretory bacterial aggregating factor (SBAF) activity. These glycoproteins also bind immunoglobulins; a secretory binding factor for immunoglobulins (SBFI) with EDTA-reversible activity is found in amniotic fluid. Agglutination of particles by very small amounts of secretory antibody is facilitated by reversible and irreversible binding of antibody to SKF/SBAF active glycoproteins. EDTA effects on the carrier glycoproteins make the bound antibody activity EDTA-sensitive. The SKF/SBAF glycoproteins also have EDTA-sensitive interactions with each other and possibly with mucins. These complex interactions of secretory glycoproteins and immunoglobulins are of importance in mucosal protection.

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.

A rapid alpha-fetoprotein radioimmunoassay.

A simple, reliable and inexpensive alpha-fetoprotein radioimmunoassay is described, in which polyethylene-glycol (PEG) is used as a precipitating agent of antibody-bound AFP. The concentrations of AFP found in amniotic fluid, newborn and maternal sera are in agreement with those reported by others. This assay fulfills the requirements of a screening test for fetal abnormalities and other clinical applications.

Allergens in cow hair and dander. Origin of cow allergens in the environment.

Quantitative immunoelectrophoretic methods were used for the analysis of the allergens in cow hair and dander and for comparison with related preparations. The immunoelectrophoretic precipitation pattern of an extract from cow hair and dander showed 17 precipitates. Crossed radioimmunoelectrophoresis showed four of these to be major allergens of the extract, and these allergens are common major allergens in four investigated cow breeds. The allergens are associated predominantly with hair and dander, but they were also demonstrated in cow saliva, urine, whey, amniotic fluid and beef, as well as in cow-hide products. Allergens displaying partial immunological identity with the major allergens of cow hair and dander were found in extracts from goat and sheep pelts, in products made of these materials such as carpet and knitting wool, and in carpets made of animal hair.

Secretory IgA and IgM antibodies to E. coli O and poliovirus type I antigens occur in amniotic fluid, meconium and saliva from newborns. A neonatal immune response without antigenic exposure: a result of anti-idiotypic induction?

Antibodies to E. coli O-antigens and poliovirus type I antigen as well as total SIgA were analysed using enzyme-linked immunosorbent assay (ELISA), in amniotic fluid and in meconium, urine and saliva from neonates. Secretory IgA and IgM antibodies to E. coli and poliovirus antigens were found in saliva as well as in most meconium samples taken during the first day of life. SIgA could be quantified in all types of samples including amniotic fluid. The finding of secretory IgA and IgM antibodies to E. coli and poliovirus type I antigens in early samples from an infant of a hypogammaglobulinaemic mother, given regular intravenous (i.v.) immunoglobulin prophylaxis, but still lacking IgA and IgM antibodies, supports a fetal origin for at least part of the secretory antibodies detected in the different samples. Since it is unlikely that the fetus has been exposed to poliovirus, which is rare in Sweden, it is hypothesized that the stimulus inducing the SIgA and IgM antibodies found in the neonate could be anti-idiotypic antibodies from the mother.

Quantitation of soluble HLA-DR antigens in human serum and other body fluids.

The existence of soluble forms of MHC class II molecules is well established. To quantify soluble HLA-DR antigens (sHLA-DR) in human serum and other body fluids, we developed an enzyme immunoassay using two non-overlapping HLA-DR-specific monoclonal antibodies (RoDR, BL-la/5) and an immunoaffinity chromatography-purified sHLA-DR standard. In serum of healthy individuals, sHLA-DR levels were found in the range between 0.6 and 3 ng/ml (median 0.85 ng/ml) whereas EDTA plasma samples showed concentrations about 20 times higher (median 21 ng/ml). In tears, saliva, sweat, urine, amniotic fluid, cerebrospinal fluid, and bronchoalveolar lavage, sHLA-DR could also be detected. No association was found between sHLA-DR serum levels and distinct HLA specificities. In the sera of patients with autoimmune diseases, slightly enhanced sHLA-DR values were found (juvenile rheumatoid arthritis: median 2.0 ng/ml, lupus erythematosus: 1.5 ng/ml, diabetes mellitus: 2.1 ng/ml).

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.

The nature of secretory agglutinins and aggregating factors. III. Secretory conglutinin-like factor SKF detects a cross-reaction between bacteria and complement component C3.

Secretory conglutinin-like factor (SKF) reacts directly with an unknown surface component of some, but not all, oral gram-positive organisms. The absorption of SKF by bacteria is EDTA-sensitive and cannot be blocked with immunoglobulins. High levels of SKF in EDTA extracts of washed salivary sediment reveal the direct in vivo reaction of SKF with oral bacteria. Mixed aggregation with alexinated erythrocytes showed the SKF corresponds to the secretory bacterial aggregating factor (SBAF) for Streptococcus mutans serotype c and also that for Streptococcus mitis. These reactions represent a cross-reaction between bacteria and complement component C3. SKF/SBAF non-mucin glycoproteins and immunoglobulins possess receptors for bacterial components while mucins are passive carriers of blood group determinants.

Structure and biological functions of human IgD. XIV. The development of a solid-phase radioimmunoassay for the quantitation of IgD in human sera and secretions.

A simple but sensitive radioimmunoassay method for the quantitation of IgD in sera and body fluids has been developed. Specifically purified chicken anti-delta was covalently coupled to cyanogen bromide activated filter paper discs and the discs were incubated together with the samples to be analyzed. The washed discs were next incubated with 125-I-labeled specifically purified chicken or rabbit anti-human delta-antibodies. IgD on the disc was quantified by reference to a standard curve prepared with purified human IgD. The sensitivity of this assay was approximately 10 ng/ml IgD. IgD was demonstrable in cord sera (18 of 18), hypogammaglobulinemic sera (15 of 15), amniotic fluids (6 of 6), salivas (8 of 10), normal cerebrospinal fluids (12 of 13) and cerebrospinal fluids from patients with subacute sclerosing panencephalitis (5 of 5). The finding of IgD in human secretions raises the interesting possibility that IgD may be a secretory antibody.

Human complement: onset and site of synthesis during fetal life.

The site and onset of synthesis of the various components of complement (C), in man and other mammals, has been studied by incubating fetal tissues in media containing labelled amino acid, and by the analysis of the culture fluids for the presence of newly synthesised proteins. Another useful approach has been that of detecting genetic variants of single components in pairs of maternal and fetal samples. These investigations have shown that all components of human C are produced at an early stage of fetal development and that, in cord blood, the mean level of most components is about half the value detected in samples from normal adults. In agreement with the results observed in man, the maturation of C occurs at an early stage of life in many other mammals.

The nature of secretory agglutinins and aggregating factors. I. Secretory conglutinin-like factor, secretory bacterial aggregating factors and secretory IgA antibody in human saliva and amniotic fluid.

Secretory conglutinin-like factor (SKF), secretory bacterial aggregating factors (SBAF) and 11S secretory IgA antibodies of human saliva and full term amniotic fluid were quantitated by microtitration and partially characterized. The SBAF of both saliva and amniotic fluid aggregated a variety of oral streptococci, but no secretory IgA antibodies were found in amniotic fluid. The SKF and SBAF are distinguished from 11S IgA antibodies by being inhibited with EDTA and by being more susceptible to inhibition with reducing agents. These active factors are also distinguished from submaxillary mucins. Components of normal serum inhibit both SKF and SBAF, but blood-group reactive sugars cannot block either SKF or SBAF.