Maternal Antibodies to Pneumolysin but Not to Pneumococcal Surface Protein A Delay Early Pneumococcal Carriage in High-Risk Papua New Guinean Infants

Immunization of pregnant women can be an efficient strategy to induce early protection in infants in developing countries. Pneumococcal protein-based vaccines may have the capacity to induce pneumococcal serotype-independent protection. To understand the potential of maternal pneumococcal protein-specific antibodies in infants in high-risk areas, we studied the placental transfer of naturally acquired antibodies to pneumolysin (Ply) and pneumococcal surface protein A family 1 and 2 (PspA1 and PspA2) in relation to onset of pneumococcal nasopharyngeal carriage in infants in Papua New Guinea (PNG). In this study, 76% of the infants carried Streptococcus pneumoniae in the upper respiratory tract within the first month of life, at a median age of 19 days. Maternal and cord blood antibody titers to Ply (ρ = 0.824, P < 0.001), PspA1 (ρ = 0.746, P < 0.001), and PspA2 (ρ = 0.631, P < 0.001) were strongly correlated. Maternal pneumococcal carriage (hazard ratio [HR], 2.60; 95% confidence interval [CI], 1.25 to 5.39) and younger maternal age (HR, 0.74; 95% CI, 0.54 to 1.00) were independent risk factors for early carriage, while higher cord Ply-specific antibody titers predicted a significantly delayed onset (HR, 0.71; 95% CI, 0.52 to 1.00) and cord PspA1-specific antibodies a significantly younger onset of carriage in PNG infants (HR, 1.57; 95% CI, 1.03 to 2.40). Maternal vaccination with a pneumococcal protein-based vaccine should be considered as a strategy to protect high-risk infants against pneumococcal disease by reducing carriage risks in both mothers and infants.Every year approximately 1 million children under 5 years of age die of pneumococcal pneumonia, meningitis, or sepsis, mostly in developing countries (4). Despite the efficacy of pneumococcal conjugate vaccines, Streptococcus pneumoniae remains an important cause of serious morbidity and mortality in young infants in developing countries (5, 8, 44), where the age of onset of disease is often younger than the recommended vaccination age of 6 weeks old and many of the serotypes causing serious disease are not included in currently available conjugate vaccines. Alternative vaccines and vaccine strategies are therefore needed to induce the earliest protection possible in high-risk infants.Early onset of pneumococcal colonization and prolonged carriage in the upper respiratory tract are believed to play important roles in the high incidence and early onset of pneumococcal diseases in children in developing countries (10, 25). In the highlands of Papua New Guinea (PNG), where this study was performed, all infants carry pneumococci in the upper respiratory tract by the age of 3 months old, and 60% of them are already carriers during the neonatal period at a median age of 17 days old (14). This is in contrast to high-income countries, where less than half of the children experience pneumococcal colonization within the first year of life (3, 10, 43). Besides children, pneumococcal carriage rates remain higher in adulthood in developing countries, including PNG, where approximately half of the adults carry pneumococci in the upper respiratory tract (17, 39), compared to 1 to 13% of adults in low-risk countries (12, 15, 20). Consequently, maternal pneumococcal carriage may be an important risk factor for early colonization in infants in high-risk areas, in particular considering the frequent and close contact between mother and child in the critical early period of life when infants are highly susceptible.In the first few months of life, when the human immune system is still highly immature (27), infants largely depend on passively acquired maternal immunoglobulin G (IgG) antibodies to protect themselves against invading pathogens. Immunization of pregnant women is a strategy that has been proven to reduce infection risks in both mothers and infants (9, 13, 45). This includes the potential to reduce acute lower respiratory illnesses in infants in high-risk areas, as shown with maternal immunization with the 23-valent pneumococcal polysaccharide vaccine (36, 37). However, the efficacy of pneumococcal polysaccharide vaccines on reducing nasopharyngeal colonization is limited, whereas the protective effect of pneumococcal conjugate vaccines is restricted by the number of pneumococcal serotypes that can be included. On the other hand, novel vaccines based on conserved pneumococcal proteins may offer better, serotype-independent protection against pneumococcal carriage and disease. This may include maternal immunization strategies, as supported by findings in mice (21).Pneumolysin (Ply) and pneumococcal surface protein A (PspA) are two conserved proteins that are expressed by virtually all S. pneumoniae isolates and that are being considered as vaccine candidates. Pneumolysin is the thiol-activated cytolysin produced by S. pneumoniae that enables the bacterium to penetrate the host''s physical defenses through its cytotoxic effect on epithelial cells, thus facilitating carriage and disease (28). PspA is a cell wall-associated protein that plays a role in inhibiting complement-mediated opsonization (7, 33) and can prevent lactoferrin-mediated clearance (19). In contrast to Ply, PspA shows structural diversity between pneumococcal strains and has been classified into three families based on the sequence variability of the most C-terminal 100 amino acids of the N-terminal domain of PspA. Although S. pneumoniae strains expressing family 1 or 2 PspA proteins account for 98% of clinical isolates, protective PspA-specific IgG antibodies binding to this highly variable region are family dependent (7).Both Ply and PspA have been shown to be highly immunogenic and to protect mice against disease and colonization following pneumococcal challenge (2, 6, 7, 11, 34). There is evidence that in humans naturally acquired IgA and IgG antibodies to PspA and Ply can mediate protection against subsequent pneumococcal carriage and disease (22, 24, 30, 31, 38, 46). Moreover, naturally acquired antibodies to Ply and PspA have been shown to be transferred from mother to child and to protect against early pneumococcal carriage and infection, at least in populations in low-risk areas (18, 38). It is not known whether these findings hold true for areas of high endemicity, where infants are at a considerably higher risk for early carriage and disease.In order to understand the role of maternal antibodies to Ply and PspA in protecting high-risk infants against early carriage, we studied antibody titers in paired maternal and cord blood samples in relation to the infant''s age of first pneumococcal nasopharyngeal carriage. We hypothesized that, compared to lower-risk settings, maternal Ply- and PspA-specific antibody titers would be higher and would be associated with a delay in the age of first pneumococcal carriage in the offspring.     

CD4 T Cell Memory and Antibody Responses Directed against the Pneumococcal Histidine Triad Proteins PhtD and PhtE following Nasopharyngeal Colonization and Immunization and Their Role in Protection against Pneumococcal Colonization in Mice

The present study was undertaken to understand the role of vaccine candidates PhtD and PhtE in pneumococcal nasopharyngeal (NP) colonization, their ability to induce CD4 T cell memory and antibody responses following primary NP colonization, and their contribution to protection against secondary pneumococcal colonization in mice. The study was also aimed at understanding the potential of immunization with PhtD and PhtE in eliciting qualitative CD4 T cell memory responses and protection against pneumococcal NP colonization in mice. PhtD and PhtE isogenic mutants in a TIGR4 background (TIGR4 ΔPhtD and TIGR4 ΔPhtE) were constructed and found to have a significantly reduced colonization density over time in the nasopharynges of mice compared to those of mice colonized with wild-type TIGR4. Mice with primary colonization by wild-type TIGR4, TIGR4 ΔPhtD, or TIGR4 ΔPhtE were protected against secondary colonization by wild-type TIGR4; nonetheless, the clearance of secondary colonization was slower in mice with primary colonization by either TIGR4 ΔPhtD or TIGR4 ΔPhtE than in mice with primary colonization by wild-type TIGR4. Colonization was found to be an immunizing event for PhtD and PhtE antigens (antibody response); however, we failed to detect any antigen (PhtD or PhtE)-specific CD4 T cell responses in any of the colonized groups of mice. Intranasal immunization with either PhtD or PhtE protein generated robust serum antibody and CD4 Th1-biased immune memory and conferred protection against pneumococcal colonization in mice. We conclude that PhtD and PhtE show promise as components in next-generation pneumococcal vaccine formulations.     

Prospective Study of Prevalence and Risk Factors for Hepatitis C in Pregnant Egyptian Women and Its Transmission to Their Infants

Aim

To estimate the hepatitis C virus (HCV) vertical transmission rate, the effect of potential risk factors, and the pattern of HCV antibody response and viremia in HCV-infected infants in Benha, Egypt.

Methods

A total of 1224 pregnant women who were treated at Benha University Hospital, Egypt, were included in the study. They completed a questionnaire about risk factors for HCV acquisition and suspected risk factors for mother-to-infant transmission and were tested for HCV antibody using a third-generation ELISA test. Women positive for HCV antibody were tested for HCV RNA by polymerase chain reaction. Peripheral blood of infants of positive HCV-RNA women was tested for HCV antibody and HCV-RNA at 1 and after 6 months of age.

Results

Out of 1224 pregnant women, 105 (8.6%; 95% confidence interval, 7.05-10.17) were positive for HCV antibody. Only 83 (6.8%; 5.39-7.21) were positive for HCV-RNA. HCV infection was associated with older age (1.16; 1.1-1.2, P = 0.001), blood transfusion (2.69; 1.2-6.0, P = 0.016), and HCV infection of the husband (5.47; 1.4-21, P = 0.014) or other household members (2.29; 1.2-4.6, P = 0.019). Out of 53 infants tested at first month, 43 (81%; 71-92%) were positive for HCV antibody, but only 7 (13%; 4.1-22%) were positive for HCV-RNA. After 6 months, only 2 (3.8%; 0-8.95%) remained positive for HCV RNA.

Conclusions

The prevalence of HCV in pregnant women in Egypt is lower than previously reported and the potential risk factors associated with HCV infection suggest intra-familial transmission. The frequency of vertical transmission of HCV in Egypt is not substantially different from other countries and does not play a role in the high prevalence of HCV in Egypt.Worldwide, hepatitis C virus (HCV) infection is one of the most prevalent causes of liver diseases. There are estimated 300 million carriers of the virus all over the world (1). In the USA, the overall prevalence of HCV antibodies in the general population is 1.8%, the prevalence in children 6-11 years is 0.2%, and in adolescents 12-19 years old is 0.4% (2). In most developed countries, HCV infection is associated with percutaneous blood exposure, primarily as a result of blood transfusion and intravenous drug addiction (3).Egypt has the highest prevalence of hepatitis C in the world. Studies have found widely varying levels (10-50%) of the prevalence, depending on the populations covered; overall, estimates of the HCV rate in the general population range between 10 and 20% (4,5). Geographically, hepatitis C prevalence is higher in Lower Egypt (Nile delta) than Upper Egypt, and it is lower in urban than rural areas (6).In Egypt, the use of contaminated needles and syringes during mass schistosomiasis treatment campaigns during the period the 1960s-1980s has been identified as a key mode of transmission for HCV infection, suggesting that parenteral exposure continues to cause infections (7). Evidence of high interfamilial HCV transmission was found in a study in a rural community in the Nile Delta in the 1990s (5-8), although the exact modes of transmission were not identified.Vertical transmission may help to explain the high prevalence in Egypt. This type of transmission in France is estimated to be less than 6% in HIV- negative patients (9). Indeed, a review of 13 studies on vertical transmission of HCV showed that the overall rate was 5.2% (10). However, a brief report from Egypt showed that vertical transmission of HCV was 36% (11), but this study looked at a small sample of 19 out of 100 pregnant women positive for HCV antibody, and only 14 of them were positive for HCV RNA. The sample of Kassem et al (11) comprised 100 randomly selected HIV-negative pregnant women and was too small for a valid estimation of the proportion of vertical transmission. It also used a limited definition of vertical transmission, defining it as the presence of HCV RNA in cord blood, and it did not repeat the polymerase chain reaction (PCR) test for HCV-RNA for infants after 6 months.The aim of the present article was to perform a more extensive study to estimate the HCV vertical transmission rate, the effect of potential risk factors, and the pattern of HCV antibody response and viremia in HCV-infected infants in Benha, Egypt.     

Antibodies against Streptococcus agalactiae Proteins cα and R4 in Sera from Pregnant Women from Norway and Zimbabwe

Group B streptococci (GBS) express strain-variable and surface-localized proteins, which are important serotype markers and targets of protective antibodies. These include the c^α and R4 proteins, one or the other of which is expressed by approximately 75% of clinical GBS isolates. These proteins have been considered vaccine candidates. In this study, the c^α and R4 proteins were extracted by trypsin digestion of GBS and purified by sequential precipitation with trichloroacetic acid and ammonium sulfate followed by gel filtration chromatography. The proteins were used as antigens in an indirect enzyme-linked immunosorbent assay (ELISA) to measure the levels of c^α- and R4-reactive antibodies in sera from pregnant women from Norway (n = 100) and from Zimbabwe (n = 124). Antibody levels in the Norwegian group of women were significantly higher than in the Zimbabwean group, and a higher proportion of the Norwegian women contained appreciable levels of antibodies against both proteins. The antibodies traversed the placental barrier. With individual sera, a significant correlation between the anti-c^α and anti-R4 antibody levels was observed and each of the two protein antigens effectively competed for human serum antibodies both against itself and against the other antigen. Inhibition ELISA results demonstrated specificity for each of the proteins of immune antibodies raised in rabbits. These results demonstrate that (i) the majority of women of childbearing age have antibodies against c^α and R4, (ii) the levels of these antibodies differ among pregnant women in different parts of the world, and (iii) the normal human serum antibodies may target a common c^α and R4 protein site, whereas immune antibodies targeted a different site(s) specific for each protein.     

Development of Antibodies against Chondroitin Sulfate A-Adherent Plasmodium falciparum in Pregnant Women

In areas where Plasmodium falciparum is endemic, pregnant women are at increased risk for malaria, and this risk is greatest during the first pregnancy. The placenta sequesters parasites that are able to cytoadhere to chondroitin sulfate A (CSA), a molecule expressed by the placental syncytiotrophoblast, while parasites from a nonpregnant host do not bind to CSA. Cytoadherence is mediated by the expression of variants of the P. falciparum-erythrocyte membrane protein 1 family. Each member of this molecule family induces antibodies that specifically agglutinate infected erythrocytes and inhibit their cytoadherence ability. We investigated whether the higher susceptibility of primigravidae was related to the lack of immune response towards CSA-binding parasites. In a cross-sectional study, primigravidae delivering with a noninfected placenta were less likely to have antibodies agglutinating CSA-binding parasites than multigravidae (P < 0.01). In contrast, parasites from nonpregnant hosts were as likely to be recognized by the sera from women of various parities. In a longitudinal study, at 6 months of pregnancy, antibodies against CSA-binding parasites were present in 31.8% of primigravidae and in 76.9% of secundigravidae (P = 0.02). The antibodies against CSA-binding parasites inhibited the cytoadherence of a CSA-adherent parasite strain to the human placental trophoblast. Our data support the idea that the higher susceptibility of primiparae is related to a lack of a specific immune response to placental parasites.     

Antinuclear Autoantibodies in Sera of Healthy Pregnant Women and Their Offspring

ABSTRACT: The presence of autoantibodies in the fetus has previously been investigated in the offspring of mothers with autoimmune diseases, but not in the offspring of healthy pregnant women. Employing the ELISA method, we examine four SLE-associated autoantibodies (anti-dsDNA, anti-ssDNA, anti-poly(I), and anti-cardiolipin) in sera obtained from 196 healthy pregnant women and their offspring. All detected autoantibodies in maternal and blood cord sera were of the IgM isotype. Thirty-four maternal sera (17.3%) were positive for one or more tested autoantibodies: 16 (8.1%) for one autoantibody alone, 17 (8.6%) for two autoantibodies, and one (0.5%) for three autoantibodies; 1.5%, 5.6%, 9.6%, and 10.2% of the maternal sera were positive for autoantibodies against dsDNA, ssDNA, poly(I), and cardiolipin, respectively. In only one blood cord serum sample was an autoantibody (IgM anti-ssDNA) detected. This infant was born to a healthy seronegative mother. The finding that all offspring of IgM seropositive mothers are IgM seronegative is not surprising since maternal IgM autoantibodies do not cross the placenta. The finding of an IgM seropositive infant born to an IgM seronegative mother may indicate that the fetus is capable of self-production of autoantibodies.     

Changes in Soluble CD4 and CD8 Proteins in Healthy Pregnant and Postpartum Women

PROBLEM: We examined physiological changes in serum levels of soluble CD4 (sCD4) and soluble CD8 (sCD8) during pregnancy and 1–12 months postpartum to study changes in the maternal immune system during and after pregnancy. METHOD: The serum concentrations of sCD4 and sCD8 were measured by enzyme immunoassay in the sera separated from blood samples withdrawn from healthy women in the 1st, 2nd, and 3rd trimesters of pregnancy and 1,4,7, and 10–12 months postpartum (n=182) and healthy non-pregnant women (n=25), and in 90 of the women, the changes in sCD4 and sCD8 were compared with changes in the number of peripheral CD4⁺ and CD8⁺ cells measured by flow cytometry. RESULTS: The serum concentration of sCD4 decreased throughout pregnancy, from the first trimester, and recovered gradually after delivery. The serum concentration of sCD8 did not change significantly during or after pregnancy compared to the concentration in the nonpregnant controls, but the concentration 1 month postpartum was significantly higher than that in the 3rd trimester. The numbers of CD4⁺ and CD8⁺ cells decreased during pregnancy but did not change significantly after delivery. Interestingly, the ratio of the serum sCD4 level to the number of CD4⁺ cells decreased and the ratio of the sCD8 level to the number of CD8⁺ cells increased in the first and second trimesters of pregnancy, but these ratios were within the normal range from the third trimester of pregnancy to 10–12 months postpartum. CONCLUSIONS: Decreases in serum sCD4 concentration and in the ratio sCD4/CD4⁺ cells, and an increase in the ratio sCD8/CD8⁺ cells may be important factors in the immunological changes that occur during pregnancy.     

The Level of Antibodies to the Proteins of Cow's Milk in the Serum of Normal Human Infants

The coated tanned red cell technique has been used to measure the level of serum antibody in normal infants to the proteins of cow's milk.

In 286 sera of infants between the ages of 7 and 97 weeks titres up to 1000 were found with the mode around 64. This distribution was quite different from that found with adult and infant cord sera. Antibodies specific for casein, α-lactalbumin and bovine plasma albumin were shown to be present but none could be shown to β-lactoglobulin.

The object of the study was to get evidence that some normal infants were sufficiently sensitized to cow's milk proteins to support the hypothesis that sudden `cot death' in infants is due to an anaphylactic type of reaction consequent on inhalation of cow's milk.

     

孕妇临产前焦虑、抑郁及其影响因素分析

目的探讨孕妇产前心理状况及影响因素,为产前心理健康教育和心理咨询提供依据。方法采用焦虑自评量表(SAS)和抑郁自评量表(SDS)作为测评工具,对736名临产前孕妇进行焦虑、抑郁情绪测定,并分析年龄、文化程度、职业和经济收入等因素对孕妇焦虑、抑郁状况的影响。结果孕妇临产前,焦虑发生率为26.90%,抑郁发生率18.75%,与年龄、文化程度及职业有关(P<0.05)。结论年龄、文化程度和职业对孕妇产前焦虑、抑郁状况有影响,应有针对性地对孕妇开展产前心理卫生健康教育和心理咨询工作。     

母体不同孕期与新生儿血中瘦素水平的观察

目的 :观察母体在不同孕期血清与新生儿脐血中瘦素水平变化及其相关关系。方法 :应用放射免疫分析 ,随机对 3 0 0例孕前、孕早期、孕中期和临产时母体血清及新生儿脐血中的瘦素水平进行了检测。结果 :妇女孕早期与孕前血中瘦素之间变化基本一致 (p >0 0 5 ) ,从孕中期开始血清瘦素水平则明显升高 ,分娩时达到高峰 (p <0 0 5或p <0 0 1)。新生儿脐血中瘦素水平与孕前母体血中瘦素水平较为一致。妇女妊娠前、后血清瘦素水平均与体重、体重指数、腹围、子宫底高度、舒张压、收缩压呈正相关。新生儿脐血瘦素水平与出生体重呈正相关 ;而与其母体瘦素水平呈负相关。结论 :新生儿瘦素来自自身 ,其浓度主要由脂肪组织的积累程度决定。检测孕期母血中瘦素浓度对判断、预测胎儿体重帮助意义不大 ,但可以了解母体孕期体重增加程度 ,并对妊娠高血压综合征的临床观察和预后判断有一定价值     

Seroprevalences of Specific IgG Antibodies to Measles,Mumps, and Rubella in Korean Infants

In this study, the seroprevalences of measles, mumps, and rubella antibodies in infants were determined to assess the immunization strategy and control measures for these infectious diseases. Serum samples from infants < 1 year of age and their mothers were collected to measure the concentrations of specific IgG antibodies to measles, mumps, and rubella by enzyme-linked immunosorbent assay. For selected infant serum samples, measles-specific neutralizing antibody levels were determined by using the plaque reduction neutralization test. The sera from 295 of infants and 80 of their mothers were analyzed. No infants had past measles, mumps, or rubella infections. Almost all infants < 2 months of age were positive for measles and rubella IgG antibodies. However, seroprevalence of measles and rubella antibodies decreased with age, and measles IgG and rubella IgG were barely detectable after 4 months of age. The seroprevalence of mumps antibodies was lower than that of measles and rubella antibodies in infants ≤ 4 months old, and mumps IgG was barely detectable after 2 months of age. The seropositivity of measles-specific neutralizing antibody was 63.6% in infants aged 2 months and undetectable in infants ≥ 6 months old. Because the seropositivity rates of measles, mumps, and rubella antibodies were low after the first few months of age in Korean infants, active immunization with vaccines is strongly recommended for infants aged 6–11 months when measles is epidemic. Timely administration of the first dose of measles-mumps-rubella vaccine at 12 months of age should be encouraged in non-epidemic situations.     

Prevalence of Cytomegalovirus IgG Antibodies among Pregnant Women Visiting Antenatal Clinic,LAUTECH Teaching Hospital in Osogbo,Osun State,Nigeria

Cytomegalovirus (CMV) is one of the predominant viral infections that lead to congenital diseases and teratogenic risks during the perinatal stage. There is paucity of seroepidemiological data on anti-CMV IgG antibody in pregnant women in Osogbo, Osun State, Nigeria. This study was aimed at determining the seroprevalence of Cytomegalovirus IgG antibody among pregnant women visiting antenatal clinic, LAUTECH Teaching Hospital, Osogbo, Nigeria. One hundred and seventy-four sera from the pregnant women were screened by Enzyme linked Immunosorbent Assay (ELISA) for cytomegalovirus (CMV) IgG antibody. Data analysis was done using SPSS software. In this study, 105 of the 174 pregnant women were seropositive for CMV IgG antibodies giving an antibody prevalence of 60%. There was no association found between CMV IgG seropositivity and the subjects’ demographic characteristics, however, the 60.0% prevalence of CMV-IgG antibody observed amongst pregnant women in this study demands for vaccines and regular testing for the presence of CMV and its related risk factors in antenatal clinic.     

Responses to a Conjugate Pneumococcal Vaccine in Preterm Infants Immunized at 2, 3, and 4 Months of Age

Preterm infants are at an increased risk of invasive pneumococcal disease infection and, additionally, have a diminished response to Haemophilus influenzae type b (Hib) conjugate vaccines. There are little data examining the response of preterm infants to a seven-valent pneumococcal conjugate vaccine (PCV7). We examined the responses of preterm infants immunized at 2, 3, and 4 months of age to PCV7. A total of 133 preterm and 54 term infants were immunized with PCV7 and the Neisseria meningitidis group C (MCC), diphtheria, tetanus, pertussis, polio, and Hib vaccines. Pneumococcal serotype-specific IgG was measured by enzyme-linked immunosorbent assay (ELISA) pre- and postimmunization and at 12 months or following a booster of PCV7. Term and preterm responses were compared using linear and logistic regression analyses. Term infants had higher preimmunization geometric mean concentrations (GMCs) for all serotypes. Preterm infants had lower postimmunization GMCs for serotype 23F. Gestational age affected postimmunization GMCs for serotypes 4, 6B, and 23F. Preterm infants were as likely to have levels of ≥0.35 μg/ml as term infants for all serotypes except 23F. The proportions of infants with titers of ≥0.35 μg/ml for all 7 serotypes were comparable between groups. A total of 28 of 29 term infants who received a booster had levels of ≥0.35 μg/ml for all serotypes. One infant had undetectable levels for serotype 6B. Of the 32 preterm infants boosted, 9 had levels of <0.35 μg/ml for 1 serotype, and 1 had levels of <0.35 μg/ml for 2 serotypes. In nonboosted infants, GMCs for all serotypes except 6B had fallen by 12 months of age. These results support the need for a booster dose in the second year of life.The primary immunization schedule of the United Kingdom (UK) is continually evolving. While a vaccine may be demonstrated to be immunogenic in one population when administered according to one schedule, apparently, minor changes to that schedule can have an adverse effect on vaccine response. Preterm infants are at an increased risk of many of the infections we immunize against, for example, pertussis (9). Almost half the children who develop pertussis are under 4 months of age (9). Preterm infants are currently recommended to be vaccinated at the same chronological age as term infants rather than at the same age postconception.The UK primary immunization schedule in place between September 2004 and September 2006 consisted of a combined vaccine against diphtheria, tetanus, pertussis, polio, and Haemophilus influenzae type b (diphtheria-tetanus-acellular pertussis [DTaP]/inactivated polio vaccine [IPV]/Haemophilus influenzae type b [Hib]) (Pediacel; Aventis Pasteur MSD) and a conjugate vaccine against Neisseria meningitidis group C (MCC) given at 2, 3, and 4 months of age, with no booster in the second year of life (5). In 2002, the chief medical officer advised that children under 2 years of age at risk of invasive pneumococcal disease (IPD) should receive three doses of the seven-valent pneumococcal conjugate vaccine (PCV7; pneumococcal capsular polysaccharide conjugated to the carrier protein CRM₁₉₇), with their primary immunizations followed by a booster in the second year of life (4). Infants were considered to be at increased risk of IPD if they had a chronic respiratory, cardiac, renal, or liver disease or an immunodeficiency. Many preterm infants are included in these categories.A postal questionnaire survey of 73 UK neonatal intensive care units highlighted the fact that many preterm infants who are at an increased risk of IPD were not being adequately immunized because of the lack of evidence that these infants are protected by the conjugate pneumococcal vaccine (11). This survey indicated that many infants who were immunized were not receiving the recommended booster dose in the second year of life. In the UK immunization schedule at this time, none of the other vaccines in the primary schedule were boosted.The immunogenicity of PCV7 when administered to preterm infants according to the then-current UK immunization schedule was examined and compared to the response of a cohort of term infants that was previously described. As many preterm infants were not routinely receiving their 12 -month booster, we also measured antibody levels at 12 months of age.     

Differences in Circulating Dendritic Cell Subtypes in Pregnant Women, Cord Blood and Healthy Adult Women

Different subtypes of dendritic cells (DC) influence the differentiation of naíve T lymphocytes into T helper type 1 (Th1) and Th2 effector cells. We evaluated the percentages of DC subtypes in peripheral blood from pregnant women (maternal blood) and their cord blood compared to the peripheral blood of healthy non pregnant women (control). Circulating DC were identified by flow cytometry as lineage (CD3, CD14, CD16, CD19, CD20, and CD56)-negative and HLA-DR-positive cells. Subtypes of DC were further characterized as myeloid DC (CD11c⁺/CD123^±), lymphoid DC (CD11c^-/CD123⁺⁺⁺) and less differentiated DC (CD11c^-/CD123^±). The frequency of DC out of all nucleated cells was significantly lower in maternal blood than in control (P<0.001). The ratio of myeloid DC/lymphoid DC was significantly higher in maternal blood than in control (P<0.01). HLA-DR expressions of myeloid DC as mean fluorescence intensity (MFI) were significantly less in maternal blood and in cord blood than in control (P<0.001, respectively). The DC differentiation factors, TNF-α and GM-CSF, released from mononuclear cells after lipopolysaccharide stimulation were significantly lower in maternal blood than in control (P<0.01). The distribution of DC subtypes was different in maternal and cord blood from those of non-pregnant women. Their role during pregnancy remains to be determined.     

Effector and Regulatory Lymphocytes in Asthmatic Pregnant Women

Citation Bohács A, Cseh Á, Stenczer B, Müller V, Gálffy G, Molvarec A, Rigó J Jr, Losonczy G, Vásárhelyi B, Tamási L. Effector and regulatory lymphocytes in asthmatic pregnant women. Am J Reprod Immunol 2010; 64: 393–401 Problem Asthma influences pregnancy outcome and pregnancy affects asthma severity, but the immunologic mechanisms of these interactions are not fully elucidated. Method The prevalence of lymphocyte subsets was identified by cell surface markers and intracellular FoxP3 staining, in healthy non‐pregnant (HNP; N = 15), healthy pregnant (HP; N = 33), asthmatic non‐pregnant (ANP; N = 62) and asthmatic pregnant (AP; N = 61) women. Results Regulatory T cell (Treg) prevalence was higher in HP than in HNP subjects and showed a positive correlation with fetal birth weight, which was blunted in AP group. Treg prevalence was lower and invariable natural killer T cell prevalence was higher in AP patients (compared to HP). Higher naive and lower effector T cell prevalence was observed in AP than in ANP group. Conclusion Pregnancy‐induced increase in Treg cell prevalence is absent in asthmatic pregnancy that may interfere with physiological intrauterine growth. However, pregnancy‐specific inhibition of asthmatic inflammation can be detected in uncomplicated asthmatic pregnancy.     

孕妇的依恋类型与社会支持

目的:探讨孕妇的依恋类型、社会支持及两者之间的关系。方法:采用关系问卷(RQ)和亲密关系经历量表(ECR)中文版,以及社会支持量表,对1070名孕妇进行问卷调查。结果:①孕妇的依恋类型分布:安全型64.0%、轻视型17.8%、倾注型14.2%、害怕型4.1%;②四种依恋类型的孕妇在"主观支持"得分上没有显著性差异,但在"客观支持"得分上,安全型(10.39±3.47)显著高于轻视型(9.21±3.11)、倾注型(9.20±3.08)和害怕型(9.17±3.73,F(3,1030)=9.83,P<0.01)。在"支持利用度"得分上,安全型(8.32±1.92)显著高于轻视型(7.64±1.86)、倾注型(7.57±1.70)和害怕型(7.60±1.95,F(3,1030)=11.51,P<0.05)。③依恋回避与"支持利用度"(r=-0.205,P<0.01)和"总的社会支持"(r=-0.230,P<0.01)呈显著负相关。④依恋焦虑与"客观支持"(r=-0.111,P<0.01)、"总的社会支持"(r=-0.123,P<0.01)均呈显著负相关。