Breast Milk sIgA Research Articles

Breast milk oxytocin and s-IgA modulate infant biomarkers and social engagement; The role of maternal anxiety

Breastfeeding has long been known to improve infants' health and mental development and to enhance the mother-infant bond, but much less research focused on the biological composition of breast milk and its associations with the infant's biomarkers and social development. In this exploratory study, we measured oxytocin (OT) and secretory immunoglobulin-A (s-IgA), the most abundant antibody in breast milk, and evaluated their associations with the same biomarkers in infant saliva and, consequently, with infant social engagement behavior. Fifty-five mother-infant dyads were home-visit and OT and s-IgA were assessed from breast milk and from infant saliva before and after a free-play interaction. Infant social behavior was coded offline using the Coding Interactive Behavior (CIB) and maternal anxiety self-reported. A path model revealed that mother's breast milk s-IgA impacted child social engagement via its links with child OT. In parallel, maternal breast milk OT was linked with infant social behavior through its association with the infant's immunity. This path was moderated by maternal anxiety; only in cases of high anxiety breast milk OT was positively connected to infant s-IgA. Our study, the first to measure OT and s-IgA in both breast milk and infant saliva in relation to observed social behavior, underscores the need for much further research on the dynamic interplay between breast milk composition, infant biomarkers, maternal mental health, and infant social outcomes. Results may suggest that biological systems in breast milk integrate to prepare infants to function in their social ecology through bio-behavioral feedback loops that signal the degree of stress in the environment.

The Persistence of Specific Immunoglobulin A Against SARS-CoV-2 in Human Milk After Maternal COVID-19 Vaccination.

Objectives: To investigate SARS-CoV-2 specific immunoglobulin A (sIgA) in breast milk of Thai mothers post COVID-19 vaccination and/or SARS-CoV-2 infection, and to compare the sIgA among lactating mothers with varying COVID-19 vaccination regimes. Materials and Methods: A longitudinal study was conducted in lactating mothers receiving ≥2 doses of COVID-19 vaccine or confirming SARS-CoV-2-positive test as a part of an infant feeding survey. Vaccination and infection details were collected through questionnaires and interviews. Self-collected breast milk samples (30 mL) at 1, 3, and 6 months postvaccination or infection were analyzed for sIgA through enzyme-linked immunosorbent assay (ELISA). Results: Eighty-eight lactating mothers (152 milk samples), average age of 30.7 ± 6.2 years, were recruited. Fifty-five percent of milk samples were from lactating mothers with both SARS-CoV-2 infection and vaccination (hybrid immunity); 40% were from those with vaccination alone (COVID naïve). Sixty percent of lactating mothers received mixed types of vaccines. Median sIgA ratio in breast milk was 2.67 (0.82-7.85). Breast milk sIgA at 1, 3, and 6 months were higher in mothers with hybrid immunity than in COVID naïve (geometric mean [95% confidence interval]: 3.30 [2.06-5.29] versus 1.04 [0.52-2.04], 3.39 [2.24-5.13] versus 1.26 [0.77-2.06], 4.29 [3.04-6.06] versus 1.33 [0.74-2.42], respectively). No significant differences were observed among various vaccination regimes. Conclusion: sIgA against SARS-CoV-2 was detected in breast milk for up to 6 months after immunization together with infection at a greater level than after immunization or infection alone. This immunity could be transferred and protective against SARS-CoV-2 infection. Discontinuation of breastfeeding among mothers who received COVID vaccination or experienced infection should be discouraged. Clinical Trial Registration number: TCTR20220215012.

THE CONTENT OF SECRETORY IMMUNOGLOBULIN A IN BREAST MILK OF PATIENTS WITH LACTATIONAL MASTITIS

Introduction. The protective function of breast milk is provided by a number of specific and non-specific anti-infective factors: secretory immunoglobulin A, immunoglobulins A, G, M, E, cellular elements (neutrophils, lymphocytes, macrophages), cytokines, lactoferrin, lysozyme, oligosaccharides, bifido- and lactobacteria, antioxidants and.
 The main class of human milk immunoglobulins is secretory immunoglobulin A (sIgA), which protects the surfaces of mucous membranes from the penetration of microorganisms, neutralizes toxins and localizes viruses, and stimulates phagocytosis. Currently, information on the local level of secretory immunoglobulin A in the development of the inflammatory process in the mammary gland is not numerous and requires research.
 The aim of the study. To assess the content of secretory IgA in breast milk of patients with lactational mastitis.
 Research metods. The study dealt with breast milk of 97 women aged 18 to 36 (average age: 26±5 years old). The standard indicators of the secretory immunoglobulin A contents in 30 practically healthy lactating women of the same age – the control group – were the issue of the analyses. The first group included 30 women with lactostasis, the second group consisted of 37 women with lactational mastitis. The content of secretory immunoglobulin A was determined by enzyme immunoassay using an automatic STAT FAX 303 plus analyzer.
 Results and discussion. The concentration of sIgA in breast milk with lactostasis is on average 0.72±0.04 mg/ml, which is 3 times higher than the control indicator (0.24±0.02 mg/ml; p<0.05). During the development of lactational mastitis, the level of sIgA is 0.75±0.05 mg/ml, which exceeds the control values by 3.1 times (р<0.05). The content of sIgA in the breast milk of women with lactostasis does not differ from the level of this immunoglobulin in patients with lactational mastitis. A high concentration of sIgA indicates the activation of immune protection on mucous membranes.
 Conclusions. Increased production of secretory immunoglobulin A in breast milk was found in experimental groups compared to practically healthy women, which indicates activation of local humoral immunity as a reaction to infection.

Factors associated with secretory IgA levels in colostrum and breastmilk

Background Secretory IgA (sIgA) content of breastmilk in the first postpartum month is a reflection of the pregnant woman's immune response to environmental antigen exposure. The role of secretory IgA in breastmilk is to protect and support the development of the neonatal immune response in early life.
 Objective To examine possible factors associated with sIgA levels in breastmilk and colostrum, including environmental exposure, food consumed, maternal history of atopy, and the appearance of allergic symptoms in infants. As a secondary objective, we determined the association between infant factors (IgE, exposure to cigarette smoke) and maternal factors (sIgA, maternal allergies) with infant allergies.
 Methods This prospective cohort study of 80 postpartum mothers and their infants was conducted at Sultan Agung Islamic Hospital, Semarang. We collected maternal colostrum on the second or third postpartum day and mature milk between the 22nd to 25th postpartum day. Exposure factors to mothers and infants in the final trimester of pregnancy up to one month postpartum was recorded through a questionnaire and home visits. The infant’s IgE level was measured at 4 months of age.
 Results Mean colostrum sIgA was 108.9 (SD 16.5) mg/dL (95%CI 97.9 to 121.1 mg/dL) and mean mature milk sIgA was 94.1 (SD 23.9) mg/dL (95%CI 89.1 to 99.2 mg/dL). Mean colostrum sIgA levels were higher in mothers exposed to cigarette smoke [119.1 (SD 1.7) vs. 92.9 (SD 1.5) mg/dL; P=0.026] and frequent infections [128.2 (SD 1.7) vs. 95.9 (SD 1.6) mg/dL; P=0.007] compared to that in unexposed mothers. Mean colostrum sIgA was also higher in mothers with atopic allergy than in those without (136.8 mg/dL vs. 99.3 mg/dL; p=0.017) and in mothers of infants with IgE levels >29 IU/ml than in mothers of infants with IgE levels <29 IU/mL (136.8 vs. 101.2 mg/mg/dL; P=0.045). Elevated colostrum sIgA (>136.8 mg/dL) was not associated with allergies in the infants (P=0.269).
 Conclusions Maternal atopic allergy and frequent infections are associated with increased colostrum sIgA levels. Breastmilk sIgA levels are not associated with allergies in the infant. Maternal exposure to antigens may stimulate the production of specific breastmilk sIgA.

Prevention of Atopic Dermatitis in Mice by Lactobacillus Reuteri Fn041 Through Induction of Regulatory T Cells and Modulation of the Gut Microbiota.

The development of atopic dermatitis (AD) in infants is closely related to the lagging development of intestinal microbiota, including that inoculated by breast milk bacteria, and immune development. Lactobacillus reuteri Fn041 is a secretory immunoglobulin A (sIgA) -coated bacterium derived from human milk. We intervene with L. reuteri Fn041 in maternal and offspring BALB/C mice during late gestation and lactation and after weaning of the pups, respectively. AD is then induced with MC903. L. reuteri Fn041 significantly suppresses AD symptoms such as skin swelling, mast cell, and eosinophil infiltration. This effect is attributed to the regulation of the systemic Th1 and Th2 cytokine ratios and the promotion of CD4+ CD25+ Foxp3+ regulatory T cell proliferation in mesenteric lymph nodes. It is also associated with the regulation of intestinal microbiota, particularly promoting Lactobacillus and Akkermansia. Our study strengthens the understanding that breast milk-derived sIgA coated potential probiotics are involved in the development of infant intestinal microbiota, thus promoting immune development and preventing allergic diseases, and expanding the knowledge of breast milk sIgA and bacterial interactions on infant immune development.

Safety and immunogenicity of an investigational maternal trivalent group B streptococcus vaccine in pregnant women and their infants: Results from a randomized placebo-controlled phase II trial

BackgroundThis study evaluated the safety and immunogenicity of an investigational trivalent group B streptococcus (GBS) vaccine in US pregnant women, transplacental serotype-specific antibody transfer and persistence in infants, and serotype-specific antibodies in breast milk. MethodsThis randomized, observer-blind, placebo-controlled trial administered one dose of trivalent GBS vaccine (n = 49) or placebo (n = 26) to healthy pregnant 18–40-year-old women at 240/7–346/7 weeks’ gestation. Women were enrolled from March 2014 to August 2015. Safety follow-up continued through postpartum day 180. Primary immunogenicity objectives were to evaluate serotype Ia/Ib/III-specific immunoglobulin G (IgG) levels in sera from women on day 1 (pre-vaccination), day 31, delivery and postpartum days 42 and 90, and from infants at birth (cord blood), days 42 and 90. Antibody transfer ratios (cord blood/maternal sera at delivery) and serotype-specific secretory immunoglobulin A (sIgA) and IgG in breast milk after delivery and on postpartum days 42 and 90 were evaluated. The planned sample size was not based on statistical assumptions for this descriptive study. ResultsBaseline characteristics were similar between groups. Serious adverse events were reported for 16% of GBS-vaccinated women and 15% of their infants, and 15% of placebo recipients and 12% of their infants; none were fatal or deemed vaccine-related. Serotype-specific IgG geometric mean concentrations (GMCs) were 13–23-fold higher in vaccine vs placebo recipients on day 31 and persisted until postpartum day 90. Median antibody concentrations were substantially higher in women with detectable pre-vaccination antibody concentrations. Antibody transfer ratios in the vaccine group were 0.62–0.82. Infant IgG GMCs and breast milk sIgA GMCs were higher in the vaccine vs the placebo group at all timepoints. ConclusionsMaternal immunization with the trivalent GBS vaccine in US women had a favorable safety profile, elicited antibodies that were transplacentally transferred and persisted in infants for a minimum of 3 months. Clinical trial registrationClinicaltrials.gov, NCT02046148

Impact of Breast Milk Secretory Immunoglobulin A on Infants Acute Gastroenteritis

BACKGROUND: Acute gastroenteritis is one of the most common infections in childhood and it can be especially dangerous in the first 6 months of life with a higher risk of moderate and severe dehydration, especially in infants who are not exclusively breastfed. Secretory immunoglobulin A (sIgA) is the first line of defense on the intestinal epithelium from pathogenic microorganisms and intestinal toxins.
 AIM: The aim of this study was to determine whether breast milk sIgA has some protective effect on the intestinal epithelium as well as on the severity and duration of the clinical signs in infants with acute gastroenteritis depending on the type of nutrition.
 MATERIALS AND METHODS: A total of 23 infants with acute gastroenteritis divided into two groups based on the feeding patterns (type of milk) were included in the study. Investigated indicators were severity of symptoms, dehydration degree, and the need for parenteral rehydration.
 RESULTS: We identified a statistically significant association between group affiliation and the sIgA levels in stool between the first and the second groups (p = 0.001346). The most common cause of acute gastroenteritis in infants was Rotavirus. Our study has shown that exclusive breastfeeding reduces the risk of Rotavirus infection, especially in the first 6 months of life, OR = 0.0758, 95% confidence interval (CI) (0.0071–0.8074).
 CONCLUSION: The presence of breast milk sIgA in infants has an effect on the severity of the clinical picture of acute gastroenteritis by reducing the frequency of vomiting, the number and severity of diarrheal episodes, the risk of moderate and severe dehydration, and fever frequency.

Administration of a Multi-Strain Probiotic Product to Women in the Perinatal Period Differentially Affects the Breast Milk Cytokine Profile and May Have Beneficial Effects on Neonatal Gastrointestinal Functional Symptoms. A Randomized Clinical Trial.

Background: Probiotic supplementation to women during pregnancy and lactation can modulate breast milk composition, with immune benefits being transferred to their infants. Aim: The aim of the study was to evaluate the effect of high-dose probiotic supplementation to women during late pregnancy and lactation on cytokine profile and secretory IgA (sIgA) in breast milk and thus to study if differences in breast milk composition can affect lactoferrin and sIgA levels in stool samples of newborns. The safety of maternal probiotic administration on neonatal growth pattern and gastrointestinal symptoms were also evaluated. Methods: In a double-blind, placebo-controlled, randomized trial, 66 women took either the probiotic (n = 33) or a placebo (n = 33) daily. Levels of interleukins (IL-6, IL-10 and IL-1β), transforming growth factor-β1 (TGF-β1), and sIgA in breast milk; and the level of sIgA and lactoferrin in newborn stool samples were analyzed at birth and then again at one month of life. Antropometrical evaluation and analysis of gastrointestinal events in newborns was also performed. Results: Probiotic maternal consumption had a significant impact on IL6 mean values in colostrum and on IL10 and TGF-β1 mean values in mature breast milk. Fecal sIgA mean values were higher in newborns whose mothers took the probiotic product than in the control group. Probiotic maternal supplementation seems to decrease incidence of infantile colic and regurgitation in infants. Conclusion: High-dose multi-strain probiotic administration to women during pregnancy influences breast milk cytokines pattern and sIgA production in newborns, and seems to improve gastrointestinal functional symptoms in infants.

Glutathione Transferase as a Potential Marker for Gut Epithelial Injury versus the Protective Role of Breast Milk sIgA in Infants with Rota Virus Gastroenteritis.

BACKGROUND:Secretory immunoglobulin A (SIgA) plays an important protective role in the recognition and clearance of enteric pathogens.AIM:This study was designed to assess if mucosal integrity “measured by secretory IgA (SIgA)” is a protective factor from more epithelial alteration “measured by glutathione transferase” in infants with Rota gastroenteritis and its relation to infants’ feeding pattern.PATIENTS AND METHODS:This study was conducted on 79 infants aged 6 months and less from those diagnosed as having gastroenteritis and admitted to Gastroenteritis Department in Abo El Rish Pediatric Hospital, Cairo University. Plasma glutathione s-transferases and Stool SIgA were measured using ELISA technique. Rota virus detection was done by Reverse transcriptase PCR.RESULTS:SIgA was found to be significantly positive in exclusive breast fed infants, Glutathione transferase was significantly more frequently positive in Rota positive cases than Rota negative cases by Reverse transcriptase PCR. A significant negative correlation between Glutathione transferase and Secretory IgA was found, (p < 0.05).CONCLUSION:Breast feeding should be encouraged and highly recommended in the first two years of life as it provides Secretory IgA to breast fed infants who in turn protect them against epithelial damage caused by Rota viral gastroenteritis.

Maternal and Infant Secretory Immunoglobulin A across the Peripartum Period.

Salivary secretory immunoglobulin A (sIgA) concentrations change over early infancy. The primary immunoglobulin in breast milk is sIgA, however, no study has examined the role of maternal sIgA in relation to infant salivary sIgA. This study aimed to examine within-source associations and mean level changes of maternal and infant sIgA across the first 6 months of life, to examine the interrelations between maternal and infant sIgA across the first 6 months of life, and to determine the association between breastfeeding and infant sIgA. Participants were a convenience sample of 51 mother-infant dyads. Salivary sIgA was collected from the mother in the third trimester. Infant and maternal salivary and maternal breast milk sIgA was collected at approximately 1, 3, and 6 months postpartum. Maternal salivary sIgA showed no mean level change across the visits, and levels were moderately associated over time. Breast milk sIgA was moderately associated over time; infant salivary sIgA was weakly associated over time. Both breast milk and infant sIgA levels decreased from 1 to 3 months postpartum. Maternal salivary sIgA was not related to infant or breast milk sIgA. Breastfed infants had lower levels of salivary sIgA. Likewise, higher concentrations of breast milk sIgA were related to lower concentrations of infant sIgA. Maternal salivary sIgA is highly stable over the peripartum period, whereas breast milk and infant salivary sIgA was variable. Infant secretory IgA development does not depend positively on maternal salivary or breast milk sIgA.

Quantification of vaccine-induced antipertussis toxin secretory IgA antibodies in breast milk: comparison of different vaccination strategies in women.

Pertussis vaccination during pregnancy or immediately after delivery is a strategy that is increasingly being recommended to protect young infants from disease. Breast milk contains disease-specific antibodies that can contribute to the protection of young infants. The composition of breast milk could be altered by vaccination during pregnancy or near delivery. However, the quantification of these antibodies in breast milk lacks standardization. In this paper, sample preparation procedures and detection methods for total and antipertussis toxin (anti-PT) secretory immunoglobulin (sIg) A are proposed that can be accurately repeated and are in accordance with European Medicines Agency and Food and Drug Administration requirements. Both antibody analytes were measured in breast milk samples of lactating women obtained 8-9 weeks postpartum to compare different maternal pertussis vaccination strategies: vaccination during pregnancy, shortly after or at delivery (cocoon), less than 5 years before delivery or more than 5 years before delivery. The validated immunoassays could quantitatively detect total and anti-PT sIgA in the processed breast milk samples. Significantly higher levels of anti-PT sIgA were measured in breast milk after pertussis vaccination during pregnancy or at delivery [geometric mean concentration (GMC): 2.56 and 2.15 IU/mg] in contrast to mothers with no recent (>5 years) pertussis vaccination (GMC: 0.96 IU/mg; P = 0.014 and P = 0.028). Vaccination against pertussis in the second/third trimester of pregnancy or immediately postpartum significantly increased the levels of anti-PT sIgA in breast milk.

Alteration of secretory IgA in human breast milk and stool samples after the intake of a probiotic — report of 2 cases

Abstract Only a few studies reveal immunological changes in breast milk after the intake of probiotic and none focus on secretory IgA (sIgA). The aim our report was to investigate the levels of sIgA in human breast milk and stools before and after 4 weeks of probiotic intake in a patient with ulcerative colitis (UC) and a control. The study included 2 lactating women: 1 with UC and 1 control. Both received daily 3.75 billion viable Lactobacillus bulgaricus for 28 days. SIgA was measured in breast milk and stools before and after the probiotic intake. The concentration of sIgA in breast milk before the probiotic intake in UC was 408.5 vs 137.4 µg/ml in contol. Fecal sIgA in UC was 420 vs 274 µg/ml in control. After 28 days of probiotic intake there was a decrease in breast milk sIgA in UC but an increase in control — 266.7 vs 914 µg/ml respectively. There was an increase in fecal sIgA both in UC and control — 674.4 vs 1033 µg/ml. It is tempting to speculate that the different sIgA secretion towards the probiotic may be a result of an altered mucosal immune response in UC.

Hiv-specific secretory IgA in breast milk of HIV-positive mothers is not associated with protection against HIV transmission among breast-fed infants

To test whether secretory immunoglobulin A (sIgA) to human immunodeficiency virus (HIV) antigens in breast milk of HIV-positive women is associated with protection against HIV transmission among breast-fed infants. Nested, case-control design in which HIV-specific sIgA was measured in breast milk collected from 90 HIV-positive women enrolled in a study in Lusaka, Zambia. Milk samples were selected to include 26 HIV-positive mothers with infected infants (transmitters) and 64 mothers with uninfected infants (nontransmitters). HIV-specific sIgA was detected more often in breast milk of transmitting mothers (76.9%) than in breast milk of nontransmitting mothers (46.9%, P = .009). There were no significant associations between HIV-specific sIgA in breast milk and other maternal factors, including HIV RNA quantities in breast milk, CD4 count, and plasma RNA quantities. HIV-specific sIgA in breast milk does not appear to be a protective factor against HIV transmission among breast-fed infants.

Micronutrient deficiency and supplementation in Indonesian infants. Effects on immune function.

Health of infants in developing countries is constantly challenged by pathogens. Unfortunately, the immune system of newborn infants is immature, developing during the first year of life to attain adequate immunocompetence at about one year of age. During the first few months of life, maternal antibodies (especially IgG) acquired in utero circulate and protect the newborn. In addition, via breast milk, the infant acquires considerable amounts of immunoglobulins (mostly sIgA) and possibly other humoral and cellular components of the mother’s immune defence. The protective effect of sIgA in breast milk is restricted to the gut. The precise role of the other immunomodulatory components of breast milk, remains unclear.

Induction of functional secretory IgA responses in breast milk, by pneumococcal capsular polysaccharides.

Capsule-specific secretory IgA (s-IgA) in breast milk may enhance protection against pneumococcal disease in infants. After immunization of 3 lactating mothers with 23-valent polysaccharide vaccine, specific s-IgA, but not IgG, increased by >2-fold in milk of at least 1 subject for 6 of 7 serotypes. The s-IgA was predominantly IgA1, in secretory form, and highly specific with avidity distinct from serum IgA and IgG. Milk whey from 2 immunized women supported dose- and complement-dependent killing of Streptococcus pneumoniae serotypes 19F and 14 by human neutrophils, as did purified s-IgA to serotype 19F. These data reveal that capsule-specific human s-IgA in breast milk can initiate killing of S. pneumoniae, providing proof of concept that vaccine-induced human mucosal s-IgA can support functional bactericidal activity. Determining the biologic role for s-IgA in killing and inhibiting adherence of S. pneumoniae in vivo will contribute to the development of mucosal vaccines against S. pneumoniae.

Relaxation Training and Breast Milk Secretory IgA

To evaluate the hypothesis that breast-feeding women who participate in relaxation training will have increased secretory IgA (sIgA) levels in their breast milk compared with women not receiving training. Nonrandomized control trial of a convenience sample. Women were recruited from the postpartum floor of a university teaching hospital. The intervention took place in the women's homes. Women in the first 48 hours after delivery who were planning to breast-feed their healthy newborn infants for at least 8 weeks were approached for enrollment. Women were excluded if they had previous experience with relaxation training. At 4 to 6 weeks postpartum, we enrolled 38 women still breast-feeding their infants. Women were allocated into 3 groups. Women in group 1 were taught relaxation and had breast milk samples collected before and after the teaching. Women in group 2 had conversation with similar breast milk sample collection, and women in group 3 had 1 breast milk sample collected. Women in group 1 were encouraged to practice the relaxation once or twice a day for 2 weeks, and a second visit was made to all mothers with repeated breast milk collections. Women who were still breast-feeding at 6 to 8 weeks after study end had a final breast milk sample collected. Breast milk was analyzed for secretory IgA levels. Stress was assayed using the Symptom Checklist-90-R and open-ended questions. There was no difference in sIgA levels among the 3 groups at any time. Women who reported stress present between visit 1 and visit 2 increased their sIgA levels at the final sample collection (+0.16 g/L) compared with women who reported no stress (-0.09 g/L; P= .03). The ratings of success in relaxation in women in group 1 were related to the following sIgA levels in sample 4: poor relaxation, 0.67 g/L; fair relaxation, 0.41 g/L; good relaxation, 0.35 g/L; and very good, 0.30 g/L (P= .006). Self-reported stress appears to increase breast milk sIgA levels. Success at relaxation was inversely related to sIgA levels in the group learning relaxation.

Human immunodeficiency virus type 1 IgA antibody in breast milk and serum.

Breast-feeding plays a potentially significant role in mother to child transmission of human immunodeficiency virus type 1 (HIV-1). The additional transmission risk attributable to breast-feeding and the factors that enhance or inhibit transmission are presently unknown. One mechanism by which breast milk might inhibit HIV-1 transmission is the presence of specific antibodies directed against HIV-1 in breast milk of seropositive mothers. In this study serum and breast milk samples from women in Nairobi, Kenya, were tested to determine the prevalence of HIV-1 IgA antibodies. A Western blot test developed in our laboratory was used to detect anti-HIV-1 immunoglobulin A in serum and anti-HIV-1 secretory IgA (sIgA) in breast milk. Ninety-four percent of 63 HIV-1 seropositive women had anti-HIV-1 IgA in serum and 59% had anti-HIV-1 sIgA in their breast milk. No significant associations with maternal characteristics or serum anti-HIV-1 IgA or IgG banding patterns and the presence of anti-HIV-1 sIgA in breast milk were found. No protective effect of anti-HIV-1 sIgA was seen regarding mother to child transmission; however, further studies are necessary to determine the effect of these antibodies in maternal sera or in breast milk on the efficacy of HIV-1 transmission.

Salivary anti‐RSV IgA antibodies and respiratory infections during the first year of life in atopic and non‐atopic infants

Salivary SIgA antibodies against RS virus were studied in 105 children during the first year of life. The infants were divided into groups according to their risk of atopy. At birth 13 neonates showed measurable amounts of SIgA to RS virus. In another 26 children specific antibodies were detected but in concentrations too low for quantitative analysis. During the first year of life this increased to 29 antibody-positive samples with measurable amounts of antibody and 39 with concentrations too low for quantitative determination. At this time 8 children of the high risk group had developed symptoms of allergy. None of these children had measurable amounts of SIgA anti-RSV in their saliva. In comparison, 10 of the remaining 26 high risk infants without symptoms of allergy did have such antibodies. Atopic infants had significantly more respiratory infections during the first year of life than nonatopic infants. The avidity of SIgA anti-RSV in neonatal samples was significantly higher than avidity determined in breast milk SIgA but comparable to the avidity of serum IgG. During the first year of life a continuing decrease of salivary SIgA avidity was observed.