Phototherapy effect on CD4 lymphocytes of Full Term Neonates with Jaundice

Background Neonatal jaundice is one of the most common problems that affect newborn infants, and phototherapy is usually used for treatment. Phototherapy is generally considered a very safe and well-tolerated treatment for hyperbilirubinaemia. However, clinical users should be aware of the unwanted effects of using phototherapy. Affection of neonatal immune system due to phototherapy has been reported. Objectives Evaluation of the effect of phototherapy on neonatal immune system through measuring the level of CD4+ lymphocytes. Methods A prospective cohort study was conducted on full term newborns assigned to three groups: group1 neonates with hyperbilirubinemia treated by conventional phototherapy, group2 neonates treated by LED phototherapy and healthy neonates as control group. The percentages and absolute counts ofCD4+ lymphocytes were measured by flow cytometry before phototherapy and 48 h after exposure. Results The study showed a significant decrease in CD4+ percentage in patients after 48 h of exposure to conventional phototherapy (P value < 0.05). There was a significant decrease in CD4+ absolute counts after 48 h of exposure to both types of phototherapy. Conclusion Conventional and LED phototherapy which is used in the treatment of neonatal hyperbilirubinemia, caused a decrease in CD4+ absolute count 48 hours after phototherapy. Also conventional phototherapy caused a decrease in CD4+% 48 hours after exposure.

Single-Cell Analysis of the Neonatal Immune System Across the Gestational Age Continuum

Although most causes of death and morbidity in premature infants are related to immune maladaptation, the premature immune system remains poorly understood. We provide a comprehensive single-cell depiction of the neonatal immune system at birth across the spectrum of viable gestational age (GA), ranging from 25 weeks to term. A mass cytometry immunoassay interrogated all major immune cell subsets, including signaling activity and responsiveness to stimulation. An elastic net model described the relationship between GA and immunome (R=0.85, p=8.75e-14), and unsupervised clustering highlighted previously unrecognized GA-dependent immune dynamics, including decreasing basal MAP-kinase/NFκB signaling in antigen presenting cells; increasing responsiveness of cytotoxic lymphocytes to interferon-α; and decreasing frequency of regulatory and invariant T cells, including NKT-like cells and CD8+CD161+ T cells. Knowledge gained from the analysis of the neonatal immune landscape across GA provides a mechanistic framework to understand the unique susceptibility of preterm infants to both hyper-inflammatory diseases and infections.

Effect of Carbon Black Nanoparticle on Neonatal Lymphoid Tissues Depending on the Gestational Period of Exposure in Mice

Introduction: Particulate air pollution, containing nanoparticles, enhances the risk of pediatric allergic diseases that is potentially associated with disruption of neonatal immune system. Previous studies have revealed that maternal exposure to carbon black nanoparticles (CB-NP) disturbs the development of the lymphoid tissues in newborns. Interestingly, the CB-NP-induced immune profiles were observed to be different depending on the gestational period of exposure. It is important to identify the critical exposure period to prevent toxic effects of nanoparticles on the development of the immune system. Therefore, the present study was aimed to investigate the effect of CB-NP on the development of neonatal lymphoid tissues in mice, depending on the gestational period of exposure.Methods: Pregnant ICR mice were treated with a suspension of CB-NP (95 μg/kg body weight) by intranasal instillation; the suspension was administered twice during each gestational period as follows: the pre-implantation period (gestational days 4 and 5), organogenesis period (gestational days 8 and 9), and fetal developmental period (gestational days 15 and 16). The spleen and thymus were collected from offspring mice at 1, 3, and 5-days post-partum. Splenocyte and thymocyte phenotypes were examined by flow cytometry. Gene expression in the spleen was examined by quantitative reverse transcription-polymerase chain reaction.Results: The numbers of total splenocytes and splenic CD3−B220− phenotype (non-T/non-B lymphocytes) in offspring on postnatal day 5 were significantly increased after exposure to CB-NP during the organogenesis period compared with other gestational periods of exposure and control (no exposure). In contrast, expression levels of mRNA associated with chemotaxis and differentiation of immune cells in the spleen were not affected by CB-NP exposure during any gestational period.Conclusion: The organogenesis period was the most susceptible period to CB-NP exposure with respect to lymphoid tissue development. Moreover, the findings of the present and previous studies suggested that long-term exposure to CB-NP across multiple gestational periods including the organogenesis period, rather than acute exposure only organogenesis period, may more severely affect the development of the immune system.

Neonatal Immune System Ontogeny: The Role of Maternal Microbiota and Associated Factors. How Might the Non-Human Primate Model Enlighten the Path?

Interactions between the immune system and the microbiome play a crucial role on the human health. These interactions start in the prenatal period and are critical for the maturation of the immune system in newborns and infants. Several factors influence the composition of the infant’s microbiota and subsequently the development of the immune system. They include maternal infection, antibiotic treatment, environmental exposure, mode of delivery, breastfeeding, and food introduction. In this review, we focus on the ontogeny of the immune system and its association to microbial colonization from conception to food diversification. In this context, we give an overview of the mother–fetus interactions during pregnancy, the impact of the time of birth and the mode of delivery, the neonate gastrointestinal colonization and the role of breastfeeding, weaning, and food diversification. We further review the impact of the vaccination on the infant’s microbiota and the reciprocal case. Finally, we discuss several potential therapeutic interventions that might help to improve the newborn and infant’s health and their responses to vaccination. Throughout the review, we underline the main scientific questions that are left to be answered and how the non-human primate model could help enlighten the path.

Part 2: COVID-19 and knowledge for midwifery practice—impact and care of the baby

It is well-known that newborn infants are more susceptible to infection due to their immature host defence mechanisms. However, in relation to the COVID-19 virus, it appears that the naivete of the neonatal immune system has afforded some protection against the inflammatory response experienced by adolescents and adults. That said, COVID-19 and the associated changes in practice and policies implemented in response to the pandemic, has had an impact on the care of the baby during the perinatal and neonatal period. This article is the second in a two-part series focusing on important care issues relating to the newborn baby specifically, taken from an integrative review of current literature within the maternal and neonatal field. This paper analyses the emerging themes from selected literature to add to a developing body of knowledge; namely, physiological differences between the newborn baby and adult, neonatal management including, preterm labour and delivery, newborn resuscitation, investigations, care of the newborn, the importance of human milk and breastfeeding, and the implications of COVID-19 restrictions. Finally, an overview of the World Health Organization guidance will be outlined for a global view and summary.

Prenatal and Perinatal Environmental Influences Shaping the Neonatal Immune System: A Focus on Asthma and Allergy Origins

It is suggested that programming of the immune system starts before birth and is shaped by environmental influences acting during critical windows of susceptibility for human development. Prenatal and perinatal exposure to physiological, biological, physical, or chemical factors can trigger permanent, irreversible changes to the developing immune system, which may be reflected in cord blood of neonates. The aim of this narrative review is to summarize the evidence on the role of the prenatal and perinatal environment, including season of birth, mode of delivery, exposure to common allergens, a farming environment, pet ownership, and exposure to tobacco smoking and pollutants, in shaping the immune cell populations and cytokines at birth in humans. We also discuss how reported disruptions in the immune system at birth might contribute to the development of asthma and related allergic manifestations later in life.

Breastfeeding and COVID-19: From Nutrition to Immunity

Breastfeeding not only provides the optimum source of nutrients for the neonate and its first strong shield against infection but also lays the foundation for somatic and psychological bonding between the mother and child. During the current COVID-19 pandemic, although the guidelines of the relevant international and national agencies recommend breastfeeding by SARS-CoV-2–infected mothers, considerable insecurity persists in daily clinical practice regarding the safety of the infants and the perceived advantages and disadvantages of discontinuation of breastfeeding. This is a systematic review of the currently available information regarding the transmissibility of SARS-CoV-2 through or while breastfeeding and the protection against infection that breast milk might provide. The accumulated body of knowledge regarding the role of breast milk in the development of the neonatal immune system and protection against infection by other respiratory viruses is discussed, with a focus on the anti-inflammatory role of the antibodies, microbes, and viruses provided to the infant in breast milk and its relevance to the case of SARS-CoV-2.

Lower Functional and Proportional Characteristics of Cord Blood Treg of Male Newborns Compared with Female Newborns

Understanding the early events involved in the induction of immune tolerance to harmless environmental antigens and microbiota compounds could reveal potential targets for allergic disease therapy or prevention. Regulatory T cells (Treg), particularly induced Treg (iTreg), are crucial for the induction and maintenance of tolerance against environmental antigens including allergens. A decrease in the number and/or function of Treg or iTreg could represent an early predictor of allergy development. We analyzed proportional and functional properties of Treg in the cord blood of children of allergic mothers (neonates at high risk of allergy development) and healthy mothers (neonates with relatively low risk of allergy development). We observed a higher number of induced Treg in the cord blood of females compared to males, suggesting an impaired capacity of male immunity to set up tolerance to allergens, which could contribute to the higher incidence of allergy observed in male infants. The decreased proportion of iTreg in cord blood compared with maternal peripheral blood documents the general immaturity of the neonatal immune system. We observed a positive correlation in the demethylation of the Treg-specific demethylated region (TSDR) and the proportion of Treg in cord blood. Our data suggest that immaturity of the neonatal immune system is more severe in males, predisposing them to increased risk of allergy development.

The 2019 novel coronavirus disease (COVID-19) and neonates

In late December 2019, Wuhan, China, became the center of an unknown outbreak of pneumonia that spread rapidly throughout China and around the world, including Iran, and the World Health Organization (WHO) declared the novel disease a public health emergency with global concern. Since the COVID-19 outbreak, many studies have been performed on epidemiological data and clinical signs in adults. However, coherent studies in this field are very rare in infants, and support and attention to infants in the pandemic situation should be doubled due to the weakness and underdevelopment of the neonatal immune system. Therefore, the present study aimed to review COVID-19 infection in infants in which there are discussions on topics such as diagnostic tests, clinical manifestations, recommendations on breastfeeding, the criteria for discharge, and family education in pandemic conditions. The literature review shows no existing evidence of COVID-19 placental transmission from mother to infant, and that all samples prepared from amniotic fluid, umbilical cord blood and breast milk in mothers with COVID -19 was negative for COVID-19 infection, and the clinical manifestations of COVID-19 were non-specific in infants, especially premature infants. Given that there is a limited number of births from a mother with COVID-19, and because the epidemiological and clinical pattern of COVID-19 in infants is unclear, this review study describes diagnostic tests, clinical manifestations, breastfeeding considerations, discharge criteria, and family education in the current understanding of COVID-19 infection in newborns and provides information for better management of SARS-CoV-2 infection in newborns.

An R848 conjugated influenza virus vaccine elicits robust IgG to hemagglutinin stem in a newborn nonhuman primate model

Eliciting broadly protective antibodies is a critical goal for the development of more effective vaccines against influenza. Optimizing protection is of particular importance in newborns, who are highly vulnerable to severe disease following infection. An effective vaccination strategy for this population must surmount the challenges associated with the neonatal immune system as well as mitigate the inherent immune subdominance of conserved influenza virus epitopes, responses to which can provide broader protection. Here, we show that prime-boost vaccination with a TLR7/8 agonist (R848)-conjugated influenza A virus (IAV) vaccine elicits antibody responses to the highly conserved hemagglutinin stem and promotes rapid induction of virus neutralizing stem-specific antibodies following viral challenge. These findings support the efficacy of R848 as an effective adjuvant for newborns and demonstrate its ability to enhance antibody responses to subdominant antigenic sites in this at-risk population.