Postpartum maternal blood helper T (CD3+CD4+) and cytotoxic T (CD3+CD8+) cells: correlations with iron status, parity, supplement use, and lactation status

The maternal gut microbiome in pregnancy: implications for the developing immune system

The gut microbiome has important roles in host metabolism and immunity, and microbial dysbiosis affects human physiology and health. Maternal immunity and microbial metabolites during pregnancy, microbial transfer during birth, and transfer of immune factors, microorganisms and metabolites via breastfeeding provide critical sources of early-life microbial and immune training, with important consequences for human health. Only a few studies have directly examined the interactions between the gut microbiome and the immune system during pregnancy, and the subsequent effect on offspring development. In this Review, we aim to describe how the maternal microbiome shapes overall pregnancy-associated maternal, fetal and early neonatal immune systems, focusing on the existing evidence and highlighting current gaps to promote further research.

Rubella seronegativity in antenatal screening - Is it influenced by the introduction of universal childhood rubella immunization?

OBJECTIVE

This study examined the impact of rubella immunization, implemented in Hong Kong in phases since 1978, on antenatal rubella serological status in Chinese women.

METHODS

In a retrospective cohort study, the incidence of antenatal rubella seronegative status in our parturients managed from 1998 to 2013 was analyzed by their year-of-birth as follows: <1965 (no childhood immunization), 1965-1982 (single dose at Primary 6), and ≥1983 (two doses at age 12 months and 12 years), adjusting for other factors including age, parity, body mass index, place-of-birth status and hepatitis B surface antigen (HBsAg) status.

FINDINGS

Rubella seronegativity decreased from 12.9%, 10.5%, to 9.8% respectively, and correlated inversely (P<0.001) with year-of-birth cohorts. Despite similar demographic profiles, this correlation was found only in Hong-Kong-born women (from 12.6%, 7.5% to 6.5% respectively), who also had significant lower incidences of rubella seronegativity (OR 0.73, 0.31 and 0.29 respectively) and HBsAg seropositivity (OR 1.09, 0.63 and 0.48 respectively) than China-born women. On regression analysis, rubella seronegativity was actually significantly increased following the implementation of immunization (aOR 1.20) while it was the reverse for non-residents (aOR 0.61).

CONCLUSION

Although rubella seronegativity decreased with immunization, the effect was less than expected when adjusted for other risk factors.

Impact of iron deficiency anemia on cell-mediated and humoral immunity in children: A case control study

OBJECTIVE

The precise role of iron in immune regulation especially in children vulnerable to iron deficiency is not fully known. Hence, this study was conducted to evaluate the effects of iron deficiency anemia (IDA) and its treatment with oral iron supplementation on cell-mediated immunity (CMI) and humoral immunity (HMI) in children.

MATERIALS AND METHODS

A total of 40 children (<15 years) with IDA and 40 age-matched healthy children after satisfying the inclusion criteria were enrolled for this case-control study. Flow cytometric evaluation of absolute and relative numbers of cluster of differentiation 4 (CD4) and CD8 (cluster of differentiation 8) lymphocyte subgroups was carried out to assess the CMI and serum Immunoglobulin G (IgG), Immunoglobulin A (IgA), Immunoglobulin M (IgM) were measured to assess the HMI at baseline and 3 months post oral iron supplementation.

RESULTS

Significantly lower levels (P < 0.05) of CD4+ T-cells and decreased CD4:CD8 ratios were observed in the iron deficient children. Iron supplementation significantly improved the CD4+ cell counts and CD4:CD8 ratios. However, immunoglobulin levels weren't different between the two groups.

CONCLUSIONS

Although IDA did not influence HMI, it significantly impaired CMI, which was improved following iron supplementation for 3 months.

The role of parity status on cigarette smoke-induced modulation of anti-tumor immune mechanisms

Epidemiologic studies indicate that women who smoke cigarettes are more likely to experience adverse reproductive and immunological health effects. Despite these facts, 20-30% of American women still smoke during their reproductive years. As little is known of the relationship between smoking and the immune response during pregnancy, an investigation was conducted using parous and non-parous (virgin) B6C3F1 mice to investigate what role (if any) parity status had on cigarette smoke (CS) induced effects on immune functions important in surveillance against developing tumors. Pregnant mice were exposed to CS for 5 d/wk ( 4 hr/d) from gestational day 4 to parturition; virgin mice were exposed for an equivalent amount of time. Smoke- and parity-associated alterations in pulmonary histology and lung inflammation, along with tumor cell host resistance, and cytotoxic T-lymphocyte (CTL) activity were examined either 24- 48 hr or 5 wk post-exposure/parturition; in the parous mice, gestational parameters were also evaluated. Exposure to CS significantly increased tumor susceptibility in virgin mice first injected with EL4 lymphoma cells at the 5 wk post-exposure timepoint; tumor incidence began to increase in smoke-exposed virgin mice as early as 24- 48 hr post-exposure. Pregnancy itself increased tumor incidence in mice injected with EL4 cells 24- 48 hr after birth, but this effect then dissipated over 5 wk to levels seen in virgin mice. When EL4 injections were first performed at either timepoint in CS-exposed parous mice, the tumor incidence was not significantly different from that in the air-exposed parity-matched controls. CTL activity in CS-exposed parous mice was significantly increased from both nulliparous groups as well as from the parous air control mice examined 5 wk post-exposure. Results suggest that exposure to CS throughout gestation could act in combination with pregnancy-associated changes to up-regulate immune responses, potentially compromising fetal tolerance.

Immunomodulatory effects of the intake of fermented milk with Lactobacillus casei DN114001 in lactating mothers and their children

The healthy action of probiotics is not only due to their nutritional properties and their influence on the gastrointestinal environment, but also to their action on the immune system. The aim of the present study was to determine if 6 weeks of probiotic intake would be able to modulate the immune system in women who had recently delivered and were breast-feeding. The design consisted of a randomised, controlled and double-blind nutritional intervention study with parallel groups with a sample size of 104 women. The main variable is the T helper type 1/T helper type 2 (Th1/Th2) profile determined by measuring interferon-gamma (Th1) and IL-4 (Th2) values in peripheral blood by flow cytometry. The modifications of cytokines were evaluated in maternal milk by cytometric bead array in a flow cytometer and ELISA at three stages of breast-feeding: colostrum, early milk (10 d) and mature milk (45 d). Additionally, the anthropometry and infectious and allergic episodes in the newborn were followed up throughout the first 6 months of life. After the consumption of milk fermented with Lactobacillus casei during the puerperium, we observed a nonsignificant increase in T and B lymphocytes and a significant increase in natural killer cells. A decrease in the pro-inflammatory cytokine TNF-alpha in maternal milk and fewer gastrointestinal disturbances were also observed in the breast-fed child of the mothers who consumed L. casei. The intake of milk fermented with L. casei during the lactation period modestly contributes to the modulation of the mother's immunological response after delivery and decreases the incidence of gastrointestinal episodes in the breast-fed child.

Immune Status of Physically Active Women during Lactation

PURPOSE

The purpose of this study was to provide baseline data on immune status of exercising and sedentary exclusively lactating women. Dietary intake and body composition were also investigated to determine whether they related to immune function.

METHODS

Healthy, exclusively breastfeeding women with a body mass index between 20 and 30 kg x m were studied at 3 months postpartum. Participants in the exercise group (EG; N = 27) exercised aerobically at least 30 min x d, 3x wk, and women in the sedentary group (SG; N = 23) exercised once a week or less during the previous 6 wk. Immune status while at rest was determined by measuring: 1) a complete blood cell count and differential leukocyte count; 2) percentages and absolute counts of peripheral blood T cells (CD3+), cytotoxic T cells (CD3+CD8+), helper T cells (CD3+CD4+), B cells (CD19+), and natural killer cells (CD56+); 3) neutrophil bacterial killing and oxidative burst activity; and 4) in vitro mitogenic responsiveness of lymphocytes. Cardiorespiratory fitness, body composition, and dietary intake were also measured.

RESULTS

Participants in the EG had a significantly higher level of mean predicted cardiorespiratory fitness than women in the SG (39.5 +/- 1.1 vs 32.5 +/- 1.0 mL O2 x min x kg; P < 0.05); however, there were no significant differences in body composition or dietary intake. There were no significant differences in any of the indicators of immune status between groups. In addition, there were no significant relationships between body composition or dietary intake and immune status.

CONCLUSIONS

The results of this study suggest that women may exercise moderately during lactation and increase their fitness level without impairing their immune function.

The Impact of Energy Restriction and Exercise in Lactating Women

Exercise improves cardiovascular fitness, plasma lipids, and insulin response in lactating women. However, exercise alone, without caloric restriction, does not promote weight loss. Once lactation is established, over-weight women may restrict their energy intake by 500 kcal/day to promote a weight loss of 0.5 kg/week without affecting the growth of their infants. Moderate exercise does not affect maternal immune status or levels of sIgA, lactoferrin, and lysozyme in human milk. Further research is needed to determine the effect of exercise and energy restriction on maternal bone health and immune status and composition of human milk.

Reference values and predictors of white blood cell subset counts: a cross-sectional study among HIV seronegative pregnant women in Zimbabwe

OBJECTIVE

To identify predictors and develop reference values of white blood cell subset counts for pregnant black women in Zimbabwe.

STUDY DESIGN

In this cross-sectional study, multiple linear regression (MLR) analysis was employed to assess the relationship of WBC subset counts with age, gestational age, gravidity, season, serum retinol, beta-carotene, ferritin, folate and alpha-1 antichymotrypsin among 998 women 22-35 weeks pregnant attending antenatal care (ANC) in Harare, Zimbabwe.

RESULTS

Mean age was 24.0 (95% CI; 23.6-24.4), range 14-45 years. The mean gestational age was 29.2 (95% CI; 29.0-29.4), range 22-35 weeks. Median gravidity was 2, range 1-9. Predictors of neutrophil counts were gestational age, season and serum ferritin, the latter in interaction with gravidity (interaction, p = 0.016). Mean lymphocyte count was 0.13 x 10(9)cells/l higher in gravida >4 than gravida 1-3, and 0.35 x 10(9)cells/l higher in the late rainy than other seasons. Predictors of monocyte counts were gestational age, serum folate and season, while eosinophil counts declined with advancing gestation. Reference values adjusted or unadjusted for identified predictors were different from those of pregnant and non-pregnant white women reported in the literature.

CONCLUSIONS

Gravidity, season and micronutrient status influence WBC counts during pregnancy and therefore are of physiological and clinical importance. WBC reference values in the literature were not applicable obviating the need for local reference values.

Cytofluorometric methods for assessing absolute numbers of cell subsets in blood. European Working Group on Clinical Cell Analysis

The enumeration of absolute levels of cells and their subsets in clinical samples is of primary importance in human immunodeficiency virus (HIV)+ individuals (CD4+ T- lymphocyte enumeration), in patients who are candidates for autotransplantation (CD34+ hematopoietic progenitor cells), and in evaluating leukoreduced blood products (residual white blood cells). These measurements share a number of technical options, namely, single- or multiple-color cell staining and logical gating strategies. These can be accomplished using single- or dual-platform counting technologies employing cytometric methods. Dual-platform counting technologies couple the percentage of positive cell subsets obtained by cytometry and the absolute cell count obtained by automated hematology analyzers to derive the absolute value of such subsets. Despite having many conceptual and technical limitations, this approach is traditionally considered as the reference method for absolute cell count enumeration. As a result, the development of single-platform technologies has recently attracted attention with several different technical approaches now being readily available. These single-platform approaches have less sources of variability. A number of reports clearly demonstrate that they provide better coefficients of variation (CVs) in multicenter studies and a lower chance to generate aberrant results. These methods are therefore candidates for the new gold standard for absolute cell assessments. The currently available technical options are discussed in this review together with the results of some cross-comparative studies. Each analytical system has its own specific requirements as far as the dispensing precision steps are concerned. The importance of precision reverse pipetting is emphasized. Issues still under development include the establishment of the critical error ranges, which are different in each test setting, and the applicability of simplified low-cost techniques to be used in countries with limited resources.