Antifilarial and anti PPD IgM antibodies in cord blood

Tuberculosis and Filariasis are commonly encountered in South India, more so in the low socio-economic group. This study was undertaken to find out the fetal immune response to maternal filariasis and tuberculosis. The presence of anti-filarial and anti-PPD IgG and IgM antibodies in the mother and cord blood at the time of delivery was identified by ELISA. Six out of 29 cases showed IgM against PPD in the cord blood and 7 out of 29 cases showed IgM againstBrugia malayi antigen in the cord blood. In both instances, 6 out of 29 for PPD and 7 out of 29 for B.malayi, the maternal blood too showed the presence of IgM to these two antigens. Comparison with anti-Ascaris lumbricoides IgM antibodies in mother and cord blood in these (6 out of 29 against PPD and 7 out of 29 against S.malayi) cases did not show a similar distribution of IgM antibodies in mother and cord blood, indicating that there is a fetal response to maternal filariasis and tuberculosis.     

Study of anti tetanus IgG and IgM levels in maternal and cord sera by enzyme linked immunosorbent assay (ELISA)

The study was done to determine IgG and IgM antitetanus antibodies in mothers after antenatal immunization, and extent of transfer to the baby as measured by cord levels of tetanus specific IgG and IgM by ELISA using enzyme penicillinase and to study the effect of nutritional status of mothers on antibody response to tetanus toxoid and corresponding cord levels also to determine the number of doses required for protective antibody levels in cord blood. The results obtained in sera of 100 mothers at the time of delivery and their respective cord sera and results of 43 different control sera are discussed using ELISA technique.     

Superoxide dismutase activity in the maternal and cord blood.

Superoxide dismutase (SOD) activity was measured in the maternal and cord blood by the modified method of Beauchamp and Fridovich, using a carbonate-buffered (pH 10.2) xanthine-xanthine oxidase system. No great differences between maternal and cord blood in erythrocyte SOD levels were observed, with the exception of whole blood; namely, washed RBC showed a SOD activity of a fairly high level, which was comparable to the activities of crude SOD, but showed no difference between them. In contrast, the SOD activity in the maternal whole blood was significantly lower than that in the cord blood. In measuring SOD activity, the serum factor has a great effect, and serum contains a substance that inhibits NBT reduction. Only one band of SOD has been detected which shows identical Rf values both in maternal and cord blood by polyacrylamide-gel electrophoresis.     

Fetal Response to Maternal Ascariasis as Evidenced by Anti Ascaris Lumbricoides IgM Antibodies in the Cord Blood

ABSTRACT. The immune response of the fetus to maternal infection with Ascaris lumbricoides was studied by estimating IgG and IgM antibodies, using ELISA, in 28 paired samples of mother and cord blood. A. lumbricoides adult male, cuticle and unembryonated egg antigen was used. Toxocara canis larva antigen was used as a specificity control. Presence of IgG in the cord blood does not signify fetal response, but the presence of IgM antibodies does. IgM antibodies to Ascaris adult male antigen were present in 27 out of 28 maternal sera and 1 out of 28 cord sera. All maternal sera and only 6 cord sera showed IgM antibodies against Ascaris cuticle and 20 out of 22 maternal sera and 8 out of 22 cord sera tested, showed IgM antibodies to Ascaris unembryonated egg antigen. Sixteen out of 22 maternal sera and none out of 22 cord sera showed IgM antibody against Toxocara canis antigen, ruling out cross reaction and transplacental leak. The results of our study suggest that the Ascaris infection can spread to the fetus and elicit immune response.     

Functional immaturity of cord blood monocytes as detected by impaired response to hepatocyte growth factor

BACKGROUND: Monocytes as antigen-presenting cells play an important role in host defense and transplantation. However, there are little reports on cord blood monocytes, and the role of monocytes in cord blood transplantation is largely unknown. METHODS AND RESULTS: There are several cytokines affecting monocyte function. These include interferon-gamma, interleukin-4, interleukin-10, granulocyte macrophage-colony stimulating factor and hepatocyte growth factor (HGF). We investigated the effect of these cytokines on antigen-presenting capacity (APC) of cord and adult blood monocytes. Using either mononuclear cells or purified CD4+ T cells as responder cells, HGF enhanced APC of adult monocytes most effectively among these cytokines. In contrast, cord blood monocytes failed to respond to HGF. As HLA, costimulatory and adhesion molecules may affect APC function, we examined these antigens of monocytes following HGF stimulation. The HGF upregulated integrin alpha5 subunit (CD49e) and intercellular adhesion molecule-1 (CD54) was expressed in adult blood monocytes, but not in cord blood. In kinetic studies, HGF downregulated c-met protein/HGF receptor expression of adult monocytes in lower concentrations and at shorter incubation time as compared with that of cord blood. CONCLUSIONS: The results suggest that impaired response of cord blood monocytes to HGF may be responsible, in large part, for their functional immaturity.     

Cytochemical bioassay of parathyroid hormone in maternal and cord blood.

Parathyroid hormone and calcium were measured in plasma taken from pregnant women at term and from the umbilical veins of their infants at birth. Three assays were used to measure parathyroid hormone, a cytochemical bioassay of bioactivity and two immunoradiometric assays, one specific for the amino terminus, the other specific for the carboxy terminus of the parathyroid hormone molecule. Plasma calcium was significantly higher in the infants than in the mothers. Maternal parathyroid hormone bioactivity and the amino terminus were both slightly raised, but the carboxy terminus value was normal; these findings supported the view that late pregnancy is a time of mild physiological hyperparathyroidism. In the infants, the amino terminus was undetectable and the carboxy terminus was either undetectable or towards the lower end of the normal range: bioactivity of parathyroid hormone was considerably raised and was related to the gradient of calcium across the placenta. This suggests that the parathyroid glands are not suppressed during fetal life and that they may play an important part in the maintenance of high fetal plasma calcium concentrations.     

Concentrations of lead in maternal blood,cord blood,and breast milk.

Lead concentrations in maternal blood, umbilical cord blood, and breast milk from 114 women who were not occupationally exposed to lead were determined by graphite atomic absorption spectrophotometry. The mean concentrations of lead in maternal blood, umbilical cord blood and breast milk were 0.7, 0.55, and 0.23 mumol/l, respectively. A significant correlation was observed between maternal and umbilical cord blood (r = 0.63). A lower correlation was noted between maternal blood and breast milk (r = 0.29). These results suggest that lead freely crosses the placental barrier from mother to fetus and the transfer of this heavy metal from maternal tissues to breast milk is possible, but the metabolic mechanisms are more complicated. In addition, a longitudinal study was conducted of concentrations of lead in breast milk in nine lactating women. Results suggested no significant change in the content of lead in breast milk during early lactation.     

Fetal beta-endorphin levels in response to reductions in uterine blood flow

Fetal beta-endorphin release has been associated with fetal hypoxia. The purpose of this study was to assess the degree of uterine blood flow reduction needed to elicit fetal beta-endorphin release in the sheep since there is a large reserve of oxygen supply to the fetus. Uterine blood flow was reduced by 26 +/- 2, 46 +/- 3 and 66 +/- 2%, producing fetal oxygen content concentrations of 5.7 +/- 0.6, 4.4 +/- 0.7 and 2.6 +/- 0.3 ml/dl, respectively. Although fetal oxygen concentrations were significantly decreased in the groups with a reduction in uterine blood flow of 46 and 66%, beta-endorphin was elevated only in the latter group. It is speculated that fetal beta-endorphin is released at a level of hypoxia which leads to a decrease in fetal oxygen consumption. A reduction in uterine blood flow of 66% appears to produce a stressful environment for the fetus as measured by fetal plasma beta-endorphin levels.     

Fas and Fas ligand expression in maternal blood and in umbilical cord blood in preeclampsia.

The Fas-Fas ligand (FasL) pathway of apoptosis is abnormally activated in diseases associated with impaired immune tolerance or chronic inflammation. Pregnancy-related hypertension is a spectrum of disease that commonly causes significant morbidity in women and in their newborn infants, is associated with generalized inflammation, and may be causally related to impaired maternal-fetal tolerance. Our recent observation of enhanced trophoblast expression of FasL in one form of pregnancy-related hypertension led us to hypothesize that this group of disorders might be associated with abnormal activation of the Fas-FasL pathway. To test this hypothesis, we prospectively quantified soluble and leukocyte-associated Fas receptor and FasL in the maternal and umbilical cord blood (CB) sera of 20 gestations complicated by preeclampsia and of 18 normal control gestations, using ELISA and flow cytometric analyses. We determined higher soluble FasL levels in paired maternal and CB sera of hypertensive gestations compared with control gestations (p < 0.01); in contrast, soluble Fas levels were similar between groups. Surface expression of FasL was lower on maternal (p < 0.01) and CB (p < 0.05) neutrophils from affected gestations, whereas surface Fas expression was lower on maternal (p < 0.02), but not CB, neutrophils and lymphocytes. We conclude that expression of Fas and FasL in sera and on leukocytes is altered in gestations complicated by preeclampsia, and speculate that activation of the Fas-FasL pathway mediates associated pathologic processes in affected women and in their neonates.     

Serum zinc and copper levels in the maternal blood and cord blood of neonates

Estimation of serum zinc and copper in the maternal blood and cord blood of neonates was carried out to correlate the trace metals in the neonates and their mothers in relation to gestational age and birth weight. Sixty-five healthy neonates, both term and preterm and their mothers were selected. This cross sectional study was done at Azimpur Maternity Centre, Dhaka Medical College Hospital and Chemistry Division, Atomic Energy Centre, Dhaka, Bangladesh from July 1997 to June 1998. The estimation of trace metals was carried out by Atomic Absorption Spectrophotometry (AAS). The mean serum zinc levels in the maternal blood and cord blood were 0.47 ± 0.24 μg/ml and 0.85 ± 0.33 μg/ml respectively and the mean copper levels in the maternal blood and cord blood were 1.37 ± 0.62 μg/ml and 0.31 ± 0.32 μg/ml respectively. Cord blood zinc level was significantly higher and cord blood copper level was significantly lower than the corresponding maternal blood levels. There was no significant correlation between gestational age and serum zinc levels in the cord or maternal blood. But significant inverse correlation was found between gestational age and serum levels of copper in the maternal and cord blood.     

Isotype composition of antibodies to streptococcus group B type III polysaccharide and to tetanus toxoid in maternal,cord blood sera and in breast milk

Neonates are protected against group B streptococcal (GBS) infections and tetanus by transplacentally transferred serum antibodies. Antibodies of the immunoglobulin (Ig) G, IgM and IgA classes and IgG subclasses to the capsular polysaccharide (CPS) of type III group B streptococci (GBS III) and to tetanus toxoid (TT) were measured in sera from healthy women of fertile age and in paired maternal and cord blood sera from term and preterm pregnancies. GBS III CPS antibodies of the IgG class were found in sera from 97 out of 100 women of fertile age, but only 15 of them had antibodies above the proposed protective level (2 g/ml). TT IgG antibodies above the protective level (0.01 units/ml) were found in all sera. The IgG antibodies against GBS III CPS were mainly composed of the IgG2 subclass and to a lesser extent of IgG1. Almost all women had IgG1 antibodies against TT and 40% had IgG4 antibodies. Total IgG and IgG1 antibodies against GBS III CPS were higher in cord blood sera from 37 term neonates than in sera from their mothers whereas IgG2 antibody levels were similar. Total IgG and IgG1 antibodies against TT were also higher in the 20 term neonates tested than in their mothers. In contrast, total IgG and IgG1 to both GBS III CPS and TT and IgG2 to GBS III CPS were lower in cord blood sera from preterm neonates than in sera from their mothers. IgA antibodies to GBS III CPS were detected in 63% of breast milk samples while IgA antibodies against TT were detected in only 4%. In conclusion the study shows important differences in IgG subclass composition of antibodies against a polysaccharide and a protein antigen and in placental transfer of IgG antibodies in term and preterm babies.