Placental Transfer Of Antibodies Research Articles

Seroprevalence of dengue infection in pregnant women and placental antibody transfer

BackgroundPregnant women and infants are vulnerable for developing severe dengue. This study was conducted to determine the seroprevalence of dengue infections among pregnant women, their offsprings and its association with outcomes. MethodsA cross-sectional study was conducted among pregnant women, admitted for delivery in a tertiary mother and child hospital in Thiruvananthapuram. Blood specimens (2 ml) were collected from the women during hospitalization in the first stage along with blood samples being drawn for other investigations. Umbilical cord blood was collected from the neonates. The samples were tested using IgG enzyme-linked immunosorbent assay (ELISA). Quantitative titres were also obtained, and index ratios were calculated using optical density values. ResultsSeroprevalence of dengue in antenatal women was 6.9% (95% confidence interval [CI]: 3.4–12.48). Among cord blood samples, the seropositivity was 10.8% (95% CI: 6.3–16.6). A significant correlation (Spearman rho: 0.653 and p value <0.001) was obtained between maternal and cord sample IgG index ratios. Agreement between maternal and cord blood IgG values was obtained using kappa as 0.742. The mean weight of newborns born to IgG-positive mothers was significantly lower than babies of IgG-negative mothers (2.3 vs 2.8; t = 2.64; p = 0.01). The mean gestational age at delivery was also significantly lower in IgG-positive mothers (36.29 vs 38.04 weeks; t = 2.48; p = 0.01). ConclusionSeroprevalence of dengue in antenatal women and in their offsprings is lower than other areas endemic for dengue. Dengue infection (any time before pregnancy) may result in preterm delivery and low birth weights.

Polyclonal HIV envelope-specific breast milk antibodies limit founder SHIV acquisition and cell-associated virus loads in infant rhesus monkeys.

Breast milk HIV-1 transmission is currently the predominant contributor to pediatric HIV infections. Yet, only ~10% of breastfeeding infants born to untreated HIV-infected mothers become infected. This study assessed the protective capacity of natural HIV envelope-specific antibodies isolated from milk of HIV-infected women in an infant rhesus monkey (RM), tier 2 SHIV oral challenge model. To mimic placental and milk maternal antibody transfer, infant RMs were i.v. infused and orally treated at the time of challenge with a single weakly-neutralizing milk monoclonal antibody (mAb), a tri-mAb cocktail with weakly neutralizing and ADCC functionalities, or an anti-influenza control mAb. Of these groups, the fewest tri-mAb-treated infants had SHIV detectable in plasma or tissues (2/6, 5/6, and 7/8 animals infected in tri-mAb, single-mAb, and control-mAb groups, respectively). Tri-mAb-treated infants demonstrated significantly fewer plasma transmitted/founder variants and reduced peripheral CD4+ T cell proviral loads at 8 weeks post-challenge compared to control mAb-treated infants. Abortive infection was observed as detectable CD4+ T cell provirus in non-viremic control mAb- and single mAb-, but not tri-mAb-treated animals. These results suggest that polyfunctional milk antibodies contribute to the natural inefficiency of HIV-1 transmission through breastfeeding and infant vaccinations eliciting non-neutralizing antibody responses could reduce postnatal HIV transmission.

Managing childhood ailments: Mumps

Mumps is usually a self-limiting condition that will resolve over the course of about 1 week, with no long-term consequences. Rest and adequate fluid intake is advised and paracetamol or ibuprofen provide symptomatic relief. Children younger than 1 year of age rarely get mumps, due to acquired passive immunity from placental transfer of maternal antibodies. Mumps is most common in young people who have not been immunised with the measles, mumps and rubella (MMR) vaccine ( National Institute for Health and Care Excellence, 2013 ). This article provides some tips for parents on managing symptoms and treatments for mumps in children.

Placental transfer of antibody and its relationship to vaccination in pregnancy.

Vaccination in pregnancy boosts maternal vaccine-specific antibody concentration and therefore increases transplacental transfer of antibody to optimize protection of the infant. The purpose of this review is to describe what is known about placental transfer of antibody in the context of vaccination in pregnancy, focussing on the recent literature and areas of debate, particularly about the timing of vaccination. There is a debate about the timing of pertussis vaccination in pregnancy with some studies reporting that vaccination in the third trimester results in higher pertussis antigen-specific IgG concentrations in cord blood and others finding that the concentration is higher following vaccination in the second trimester. The impact of timing of vaccination on antibody avidity in cord blood has also been investigated and one study suggests that avidity may be increased following vaccination at 27-30 gestational weeks compared with later vaccination. Understanding placental transfer of antibody is vital in informing maternal vaccination strategy. There has been recent research about the timing of pertussis vaccination in pregnancy that has implications for the timing of both current and future vaccines to be used in pregnancy.

Parasitic Infections in Pregnancy Decrease Placental Transfer of Antipneumococcus Antibodies.

Many factors can influence maternal placental antibody transfer to the fetus, which confers important immune protection to the newborn infant. However, little is known about the effect of maternal parasitic infection on placental antibody transfer. To investigate this, we selected from a parent study of 576 pregnant Kenyan women four groups of women with term deliveries (≥37 weeks), including uninfected women (n = 30) and women with solo infections with malaria (n = 30), hookworm (n = 30), or schistosomiasis (n = 10). Maternal plasma at delivery and infant cord blood were tested via multiplex fluorescent bead assay for IgG against 10 pneumococcal serotypes (PnPs 1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F, and 23F), diphtheria toxoid, and Haemophilus influenzae type B. Infants born to mothers with prenatal malaria, hookworm, or Schistosoma haematobium infections were associated with a significantly reduced ratio of maternal to infant cord blood antibody concentration for Streptococcus pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, and 18C compared to infants of uninfected mothers. Anti-diphtheria toxoid and anti-H. influenzae type B IgG ratios were not significantly different among infection groups. Prenatal parasitic infections decrease the transfer of maternal IgG antibodies to infants for several serotypes of S. pneumoniae.

“Simulect” as a model compound for assessing placental transfer of monoclonal antibodies in minipigs

“Simulect” as a model compound for assessing placental transfer of monoclonal antibodies in minipigs

Fatal neonatal hemochromatosis as a rare cause of intrauterine growth restriction

Neonatal hemochromoatosis (NHC) is characterized by severe liver disease in the newborn accompanied by extrahepatic siderosis. This Gestational Alloimmunic Liver Disease (GALD) is resulting from the placental transfer of maternal IgG antibodies against fetal hepatocytes. Diagnosis is often only made post mortem for the severe and unexpected occurrence [1].

Incidence and seroprevalence of hepatitis E virus infection in pregnant women infected with hepatitis B virus and antibody placental transfer in infants

BackgroundHepatitis E has poor outcomes in pregnant women. Superinfection of hepatitis E virus (HEV) in patients infected with hepatitis B virus (HBV) may worsen liver disease. ObjectivesTo estimate the incidence and seroprevalence of HEV infection among HBV-infected pregnant women, to investigate the transplacental transfer of maternal anti-HEV IgG, and to compare the maternal and neonatal outcomes in anti-HEV positive and negative pregnant women. Study designTotally 391 HBV-infected pregnant women were recruited from April 2012 to October 2014. Paired mothers and infants were followed up at an average 9.8 months postpartum. Anti-HEV IgG and IgM were tested by ELISA. ResultsOf the pregnant women, none was anti-HEV IgM positive and 42 (10.7%) were IgG positive. At the follow-up, 3 seronegative women converted to anti-HEV IgG positive, with an estimated incidence of 17 per 1000 person-years. No significant differences of gestational age, preterm birth rate, Apgar score and birthweight were observed between newborns of anti-HEV IgG positive and negative mothers. Of the 42 neonates born to anti-HEV IgG positive mothers, 38 (90.5%) had anti-HEV IgG in their cord blood. The neonatal and maternal anti-HEV IgG levels were positively correlated (r=0.827, p<0.05). All infants were negative for both anti-HEV IgM and IgG at the follow-up. ConclusionsHBV-infected pregnant women rarely have novel HEV infection during late pregnancy in Jiangsu, China. Maternal anti-HEV IgG efficiently transfers into the fetuses, and disappears in infants before 10 months old.

Assessment of placental transfer and the effect on embryo-fetal development of a humanized monoclonal antibody targeting lymphotoxin-alpha in non-human primates.

An enhanced embryo-fetal development study was conducted in cynomolgus monkeys using pateclizumab, a humanized IgG1 monoclonal antibody (mAb) targeting lymphotoxin-alpha. Pateclizumab administration between gestation days (GD) 20 and 132 did not induce maternal or developmental toxicities. The ratio of fetal-to-maternal serum concentration of pateclizumab was 0.73% on GD 50 and 61% by GD 139. Decreased fetal inguinal lymph node-to-body weight ratio was present in the high-dose group without microscopic abnormalities, a change attributable to inhibition of lymphocyte recruitment, which is a pharmacologic effect of pateclizumab during late lymph node development. The effect was observed in inguinal but not submandibular or mesenteric lymph nodes; this was attributed to differential susceptibility related to sequential lymph node development. Placental transfer of therapeutic IgG1 antibodies; thus, begins during the first trimester in non-human primates. Depending on the potency and dose levels administered, antibody levels in the fetus may be pharmacologically or toxicologically relevant.

Maternal Human Immunodeficiency Virus-Associated Hypergammaglobulinemia Reduces Transplacental Transfer of Immunoglobulin G to Plasmodium falciparum Antigens in Cameroonian Neonates.

Background. Human immunodeficiency virus (HIV) infection reduces placental transfer of antibodies from mother to the fetus for many antigens; however, conflicting data exist for transfer of immunoglobulin G (IgG) to malarial antigens. The mechanism(s) underlying reduced placental transfer is unknown.Methods. Levels of maternal and cord total IgG, IgG subclasses, and cord-to-mother ratios (CMRs) were measured in 107 mother-cord pairs to 3 malarial antigens: circumsporozoite protein (CSP), apical membrane antigen 1 (AMA-1), merozoite surface protein 1 (MSP-1), and tetanus toxoid C-fragment (TTc).Results. Immunoglobulin G levels to CSP and TTc were lower in HIV+ mothers, and cord IgG to CSP, MSP-1, and TTc were significantly lower in neonates born to HIV+ mothers (all P values <.05). The prevalence of mothers with hypergammaglobulinemia was significantly higher among HIV+ women (68%) compared with HIV− mothers (8%) (P < .0001). Maternal hypergammaglobulinemia was associated with reduction in transplacental transfer of antibodies to CSP (P = .03), MSP-1 (P = .004), and TTc (P = .012), and CMRs <1 were found for MSP-1 (odds ratio [OR] = 6.5), TTc (OR = 4.95), and IgG1 to CSP (OR = 3.75, P = .025) in statistical models adjusted for maternal IgG.Conclusions. Data confirmed that HIV infections are associated with lower cord antibody levels to malarial antigens and that hypergammaglobulinemia may contribute to reduced antibody transfer.

Group B streptococcus vaccination in pregnant women with or without HIV in Africa: a non-randomised phase 2, open-label, multicentre trial

SummaryBackgroundNeonates born to women infected with HIV are at increased risk for invasive group B streptococcus (GBS) disease. We aimed to compare safety and immunogenicity of trivalent glycoconjugate GBS vaccine in pregnant women with and without HIV in Malawi and South Africa.MethodsIn our non-randomised phase 2, open-label, multicentre study, we recruited pregnant women attending two antenatal clinics, one in Blantyre, Malawi, and one in Soweto, Johannesburg, South Africa. Participants were divided into three groups on the basis of their HIV infection status (no infection, infection and high CD4 cell count [>350 cells per μL], and infection and low CD4 cell count [>50 to ≤350 cells per μL]) and received a 5 μg dose of glycoconjugate GBS vaccine (serotypes Ia, Ib, and III, with CRM197 [Novartis Vaccines, Siena, Italy]) intramuscularly at 24–35 weeks' gestation. GBS serotype-specific antibody concentrations were measured before vaccination (day 1), day 15, day 31, and at delivery, and in infants at birth and day 42 of life. The primary outcomes were safety in mothers and infants and the amount of placental transfer of GBS serotype-specific antibodies from mothers to their infants. All immunogenicity and safety analyses were done on the full analysis set, including participants who, or whose mother, correctly received the vaccine and who provided at least one valid assessable serum sample. This study is registered with ClinicalTrials.gov, number NCT01412801.Findings270 women and 266 infants were enrolled between Sept 26, 2011, and Dec 4, 2012 (90 women and 87 infants without HIV, 89 and 88 with HIV and high CD4 cell counts, and 91 and 91 with HIV and low CD4 cell counts, respectively). Seven women were lost to follow-up, six withdrew consent, one died, and two relocated. Eight infants died or were stillborn and two were lost to follow-up. Across serotypes, fold change in antibody concentrations were higher for the HIV-uninfected group than the HIV-infected groups. Transfer ratios were similar across all three groups (0·49–0·72; transfer ratio is infant geometric mean antibody concentration in blood collected within 72 h of birth divided by maternal geometric mean antibody concentration in blood collected at delivery); however, at birth, maternally derived serotype-specific antibody concentrations were lower for infants born to women infected with HIV (0·52–1·62 μg/mL) than for those born to women not infected with HIV (2·67–3·91 μg/mL). 151 (57%) of 265 women reported at least one solicited adverse reaction: 39 (45%) of 87 women with HIV and low CD4 cell counts, 52 (59%) of 88 women with HIV and high CD4 cell counts, and 60 (67%) of 90 women in the HIV-uninfected group. 49 (18%) of 269 women had at least one adverse event deemed possibly related to the vaccine (six [7%] in the HIV and low CD4 cell count group, 12 [13%] in the HIV and high CD4 cell count group, and 21 [23%] in the HIV-uninfected group), as did three (1%) of 266 neonates (zero, two [1%], and one [1%]); none of these events was regarded as serious.InterpretationThe vaccine was less immunogenic in women infected with HIV than it was in those not infected, irrespective of CD4 cell count, resulting in lower levels of serotype-specific maternal antibody transferred to infants, which could reduce vaccine protection against invasive GBS disease. A validated assay and correlate of protection is needed to understand the potential protective value of this vaccine.FundingNovartis Vaccines and Diagnostics division (now part of the GlaxoSmithKline group of companies), Wellcome Trust UK, Medical Research Council: Respiratory and Meningeal Pathogens Research Unit.

Indication of Mild Hemolytic Reaction Among Preterm Infants With ABO Incompatibility.

Among term infants, ABO incompatibility is a leading cause of hemolytic disease and neonatal jaundice. With respect to preterm infants, data are lacking. To evaluate the incidence and severity of ABO incompatibility hemolytic disease among preterm infants with respect to hemolytic and jaundice parameters. Clinical and laboratory data were collected retrospectively from the medical records of 118 ABO-incompatible preterms born at gestational age (GA) 29-34 weeks, as well as 118 controls matched for GA, birth weight, and multiplicity. All infants were born at the Sheba Medical Center Tel-Hashomer between 2009 and 2012. The study and control groups were similar on all maternal and neonatal outcome parameters. No differences between the groups were recorded throughout hospitalization regarding hematocrit levels or the need for blood transfusion. Bilirubin levels were higher among the study (ABO-incompatible) group during the first 10 days of life; however, no significant differences were found regarding the need for phototherapy. Upon evaluating subgroups divided by GA, we found no differences on any hematological and jaundice factors among preterms of 29-31 weeks, whereas among preterms of 32-34 weeks higher positive direct antiglobulin test (DAT) results (7% vs. 0% in the control, P = 0.014) as well as higher bilirubin levels were documented. Among ABO-incompatible preterm infants with GA 29-34 weeks, there is no evidence of significant hemolytic reaction derived from placental transfer of antibodies. With increasing GA, antibody transfer becomes more significant, resulting in more positive DAT results and greater incidence of neonatal jaundice.

Maternal Immunization With an Investigational Trivalent Group B Streptococcal Vaccine

To evaluate the safety and immunogenicity of an investigational trivalent group B streptococcal vaccine in pregnant women and antibody transfer to their newborns. The primary outcome of this observer-blind, randomized study was to estimate placental antibody transfer rates at birth. Secondary outcomes included measurement of serotype-specific antibodies at screening, 30 days postvaccination, at delivery, and 91 days postpartum, infant antibody levels at 3 months of age, the potential effect on routine infant diphtheria vaccination at 1 month after the third infant series dose, and safety in mother and infant participants through at least 5 months postpartum. Sample size was based on 60 participants in the vaccine group giving a probability of observing at least one adverse event of 90% if the actual rate of the event was 3.8%. From September 2011 to October 2013, 86 pregnant women were allocated in a 3:2 ratio to receive an investigational group B streptococcal vaccine containing glycoconjugates of serotypes Ia, Ib, and III or placebo. Demographics were similar across groups. Transfer ratios were 66-79% and maternal geometric mean concentrations increased 16-, 23-, and 20-fold by delivery against serotypes Ia, Ib, and III, respectively, Women with no detectable antibodies at inclusion had lower responses than those with detectable antibodies. Three months after birth, infant antibody concentrations were 22-25% of birth levels. Antidiphtheria geometric mean concentrations were similar across groups. In the vaccine and placebo groups, 32 of 51 women (63%) and 26 of 35 women (74%) reported adverse effects, respectively. The investigational vaccine was well-tolerated without safety signals in recipients and their infants or interference with routine infant diphtheria vaccination, although further studies on safety and effectiveness are needed. The investigational vaccine was immunogenic for all serotypes, particularly among women with detectable antibody levels at baseline. Antibody transfer to neonates was at similar levels to other maternally administered polysaccharide vaccines. ClinicalTrials.gov, www.clinicaltrials.gov, NCT01446289.

Reciprocal interference of maternal and infant immunization in protection against pertussis

BackgroundBecause of the current re-emergence of pertussis, vaccination during the 3rd trimester of pregnancy is recommended in several countries in order to protect neonates by placental transfer of maternal antibodies. Here, we examined the potential reciprocal interference of mother and infant vaccination in protection against pertussis in mice. MethodsFemale mice were vaccinated with acellular pertussis vaccines and protection against Bordetella pertussis challenge, as well as functional antibodies were measured in their offspring with or without re-vaccination. ResultsMaternal immunization protected the offspring against B. pertussis challenge, but protection waned quickly and was lost after vaccination of the infant mice with the same vaccine. Without affecting antibody titers, infant vaccination reduced the protective functions of maternally-derived antibodies, evidenced both in vitro and in vivo. Protection induced by infant vaccination was also affected by maternal antibodies. However, when mothers and infants were immunized with two different vaccines, no interference of infant vaccination on the protective effects of maternal antibodies was noted. ConclusionIt may be important to determine the functionality of antibodies to evaluate potential interference of maternal and infant vaccination in protection against pertussis.

Placental transfer of anti-group B Streptococcus immunoglobulin G antibody subclasses from HIV-infected and uninfected women to their uninfected infants.

Objectives:Placental antibody transfer is impaired in the context of HIV infection, which may render HIV-exposed, uninfected infants vulnerable to group B Streptococcus (GBS) disease. The GBS antibody response predominately consists of immunoglobulin G2 (IgG2) antibody. Thus we determined whether concentration and placental transfer of anti-GBS antibody subclasses was altered in HIV-infected compared with HIV-uninfected mothers.Design:A retrospective analysis of anti-GBS antibody subclasses in 38 HIV-infected and 33 HIV-uninfected mothers and their uninfected infants.Methods:Sera were analysed using a novel flow cytometric assay that quantified binding of IgG1, IgG2, IgG3 and IgG4 to serotype (ST)Ia, STIII and STV GBS bacteria.Results:IgG2 binding to GBS STIa and V was lower in HIV-infected women compared with HIV-uninfected women. Moreover, IgG2 binding to GBS STIa was also lower in HIV-exposed, uninfected infants compared with unexposed infants. However, there were no statistically significant differences in the transplacental transfer ratio of IgG2 for any GBS serotype. The transplacental transfer of total IgG was reduced for GBS STIII and V and IgG1 subclass for STIII; placental transfer of all other subclasses was comparable in HIV-affected and HIV-unaffected pregnancies.Conclusion:Anti-GBS IgG2 placental transfer is not affected by HIV infection. This is important for functional antibody against the capsular polysaccharide of GBS and provides confidence that maternal GBS vaccination may result in functional activity in HIV-infected and uninfected women.

Low pertussis antibody levels in maternal and umbilical cord blood samples in Turkey.

Pertussis continues to cause significant mortality and morbidity in many countries despite high vaccine coverage, especially among young infants. The aim of the study was to determine pertussis antibody levels in paired maternal and cord blood samples, to evaluate the placental transfer of these antibodies, and to assess whether newborn infants have adequate antibody levels against pertussis. Antibody titers to pertussis toxin (anti-PT) and filamentous hemagglutinin (anti-FHA) were measured by in-house enzyme linked immunosorbent assay (ELISA) in 251 paired maternal delivery and cord blood samples. Geometric mean concentrations (GMCs) of pertussis antibodies and cord:maternal GMC ratios were calculated. GMCs of maternal anti-PT and anti-FHA antibodies at delivery were 4.12 and 9.89 EU/ml, respectively. Cord GMCs were 133% and 131% of maternal delivery values for PT and FHA, respectively; demonstrating effective placental transfer. However, cord pertussis antibodies were at a low concentration; 5.49 EU/ml for PT and 12.73 EU/ml for FHA. Only 34.6% of infants had protective anti-PT levels (≥10 EU/ml) at birth. Anti-pertussis antibody concentrations were extremely low in pregnant women in Turkey where childhood pertussis vaccination coverage has been high for a long time. Despite effective placental antibody transfer, umbilical cord pertussis antibody concentrations are similarly low. A majority of young infants are vulnerable to pertussis infection until the onset of primary vaccinations. These data support the need for pertussis vaccination during pregnancy to prevent infant infection in Turkey.

Prenatal passive transfer of Mycobacterium tuberculosis antibodies in Asian elephant (Elephas maximus) calves.

Asian elephant (Elephas maximus) dams and their newborn calves were tested for Mycobacterium tuberculosis antibodies in serum. Blood was drawn from dams prior to calving and from calves on their day of birth. All six calves born to tuberculosis-reactive dams were also tuberculosis reactive, suggesting prenatal passive placental transfer of tuberculosis antibodies. In contrast, all three calves born to tuberculosis-nonreactive dams lacked detectable tuberculosis antibodies in pre-suckling or day-of-birth blood samples. Of the living tuberculosis-reactive calves observed from 1 to 11 yr of age, none exhibited clinical signs of tuberculosis infection or became tuberculosis culture positive. This is the first report of prenatal passive placental transfer of tuberculosis antibodies in elephants and demonstrates that detectible tuberculosis antibodies in newborn elephant calves should not be assumed to correlate with clinical tuberculosis.

Malaria and HIV infection in Mozambican pregnant women are associated with reduced transfer of antimalarial antibodies to their newborns.

Malaria and human immunodeficiency virus (HIV) infection during pregnancy affect the transplacental transfer of antibodies against several pathogens from mother to fetus, although the effect of malaria and HIV infection on the transfer of antimalarial antibodies remains unclear. Levels of total immunoglobulin G (IgG), immunoglobulin M (IgM), and IgG subtypes against the following Plasmodium falciparum antigens were measured in 187 pairs of mother-cord plasma specimens from Mozambique: 19-kDa fragment of merozoite surface protein 1 (MSP119), erythrocyte binding antigen 175 (EBA175), apical membrane antigen 1 (AMA1), and parasite lysate. Placental antibody transfer was defined as the cord-to-mother ratio (CMR) of antibody levels. Maternal malaria was associated with reduced CMR of EBA175 IgG (P = .014) and IgG1 (P = .029), AMA1 IgG (P = .002), lysate IgG1 (P = .001), and MSP1 IgG3 (P = .01). Maternal HIV was associated with reduced CMR of MSP1 IgG1 (P = .022) and IgG3 (P = .023), lysate IgG1 (P = .027) and IgG3 (P = .025), AMA1 IgG1 (P = .001), and EBA175 IgG3 (P = .001). Decreased CMR was not associated with increased adverse pregnancy outcomes or augmented risk of malaria in the infant during the first year of life. Placental transfer of antimalarial antibodies is reduced in pregnant women with malaria and HIV infection. However, this decrease does not contribute to an increased risk of malaria-associated morbidity during infancy.

Absence of antibodies against Bordetella pertussis in pregnant women and newborns in the state of Nuevo Leon

To assess placental transfer of antibodies to the child at birth and at 2 months of age. For the quantification of anti-PT IgG antibodies, we used an indirect enzyme-linked immunosorbent assay standardized by The National Institute of Epidemiologic Diagnosis and Reference (InDRE). Samples were considered negative from 0 to 48 IU/mL, indeterminate from 49 to 93 IU/mL and positive at ≥94 IU/mL. We performed a cross-sectional assessment of anti-PT IgG antibody levels in the mother, umbilical cord, and child. There was a higher concentration of IgG anti-TP in the umbilical cord (4.3%) and in the mother (1.4%), but a total absence was observed in the child (0%). The vulnerability of children to Bordetella pertussis shows the need to implement effective immunization strategies, whether actively, in the child, or passively through the mother, adolescents, and adults who are in contact with the child.

Transplacental transfer of macromolecules: proving the efficiency of placental transfer of maternal measles antibodies in mother: infant pairs.

Background:Smaller substances <600 Daltons (Da) can transit human placenta while larger ones >1000 Da may not. This may not be consistent because maternal measles antibodies (MMA) are large immunoglobulin G molecules with molecular weight of 150,000 Da, could cross the placenta in mother-infant pairs.Aim:The objective was to assess the efficiency of placental transfer of MMA in mother-infant pairs at birth.Subjects and Methods:Sera collected from mother-infant pairs were analyzed for MMA using enzyme-linked immunosorbent assay. Gestational age (GA) of newborns was determined using the last menstrual period, ultrasound scan, and the Dubowitz criteria, whereas their birth weight (BW) was measured using the bassinet weighing scale.Results:Correlation coefficient (r) of MMA of mother-infant pairs at birth was significant (P < 0.01) and comparison of mean MMA for term and postterm deliveries were significant (P = 0.001) and (P = 0.007) respectively. Goodman and Kruskal's Gamma rank correlation of GA and BW was also significant (P< 0.001).Conclusion:Passage of MMA across placenta was efficient and newborn infants are protected from measles at birth.