A comparison of secretory antibodies in breast-fed and formula-fed infants over the first six months of life

In the present study salivary IgA, anti-Escherichia coli, anti-beta-lactoglobulin and anti-poliovirus type 1 IgA and IgM in serum and saliva were evaluated longitudinally in 13 breast-fed and 14 formula-fed infants over the first six months of life. Salivary IgA was quantified by electroimmunodiffusion; specific IgA and IgM antibodies were determined in serum and saliva by ELISA. Salivary IgA was significantly lower at age one month in breast-fed compared with formula-fed infants but in breast-fed infants salivary IgA increased with age and was significantly higher at six months than at one month. In both groups of infants, at the age of six months, salivary IgA levels were significantly lower than in adult controls. No significant differences in secretory anti-E. coli were observed between the two groups of infants. Salivary anti-poliovirus IgA and IgM antibodies increased transiently only to disappear in most babies at age six months, while anti-beta lactoglobulin IgA and IgM, present in saliva at all ages, showed a wide scatter. No important differences in specific serum IgA or IgM antibodies were observed either between the groups or at different times within the groups.     

Variable increases of IgG and IgM antibodies in milk of IgA deficient women

Serum, milk and saliva from seven IgA deficient mothers were studied for the presence of IgA, IgG and IgM antibodies to Escherichia coli and polio virus antigens. Different variable patterns were obtained. One mother had very much increased IgM and IgG antibodies in milk and saliva against both antigens; the milk IgG antibodies were 11–14 times higher than the reference milk pool. Another mother showed also striking increases of both IgM and IgG antibodies in milk, as well as in saliva where the increases were much higher for the poliovirus than the E. coli antibodies. Yet another mother showed a certain increase of IgM but not of IgG antibodies in the milk. The uneven appearance of IgG and IgM antibodies in serum and secretions suggests local production. So do the differences ot antibody avidities, the variations in IgG subclass distribution of antibodies and different patterns after isoelectric focusing (IEF) /immunoblotting analysis of antibody spec-trotypes in secretions and serum.
The study illustrates the variable patterns of compensatory increases of IgG and IgM antibodies which may occur in IgA deficiency. It also shows that the milk from IgA deficient mothers can still be rich in antibodies, in spite of the lack of secretory IgA.     

Secretory IgA, free secretory component and IgD in saliva of newborn infants

AIM: To determine levels of secretory IgA (sIgA), free secretory component (FSC) and IgD in saliva of newborn infants at the age of 1 day and to evaluate the detection patterns, the influence of saliva flow and the relation to serum derived proteins. METHODS: Seventy-three healthy newborn infants were studied. Saliva was obtained from the bottom of the mouth and buccal sulci using a sterile polyethylene tube connected to a syringe. SIgA, FSC, IgD and albumin were measured by radial immunodiffusion. RESULTS: SIgA was detected in 74.0% of all saliva samples, whereas detection rates for FSC and IgD were 94.5% and 75.3%, respectively. Investigation of detection patterns and their relation to saliva flow indicated that secretion of sIgA and FSC into the oral cavity is under similar regulation. Levels of IgD were found to be independent from saliva flow, as well as from concentrations of serum-derived proteins suggesting different regulative mechanisms compared to sIgA and FSC. The flow rate of unstimulated whole saliva in newborn infants was found to be 15 times lower compared to adolescents, emphasizing the role of saliva flow as a limiting factor for secretion of sIgA and FSC. CONCLUSION: SIgA, FSC and IgD can be determined in saliva of newborn infants even in the first day of life. The saliva flow rate has to be considered when evaluating the function and biological relevance of the oral mucosal immune system of newborn infants shortly after birth.     

Slow salivary secretory IgA maturation may relate to low microbial pressure and allergic symptoms in sensitized children

It is unknown why allergic symptoms do not develop in all sensitized children. We analyzed prospectively the postnatal secretory IgA (SIgA) development and whether high SIgA levels would protect sensitized infants from developing allergic symptoms. Salivary total IgA and SIgA levels were determined by ELISA, and allergy development was investigated at 3, 6, and 12 mo and at 2 and 5 y in two birth cohorts in Estonia (n = 110) and Sweden (n = 91), two geographically adjacent countries with different living conditions and allergy incidence. Total and SIgA levels increased with age, reaching adult levels at the age of 5. Virtually, all salivary IgA in Estonian children was in the secretory form, while a major part of IgA in Swedish saliva lacked the secretory component up to 2 y of age. In Sweden, high levels of salivary IgA without secretory component correlated inversely with house dust endotoxin levels. High SIgA levels were associated with less development of allergic symptoms in sensitized Swedish children. In conclusion, postnatal maturation of the salivary SIgA system proceeds markedly slower in Swedish than Estonian children, possibly as a consequence of low microbial pressure. SIgA may limit allergy-mediated tissue damage at mucosal surfaces in sensitized individuals.     

Development of secretory immunity in breast fed and bottle fed infants.

Samples of saliva and nasal secretions were collected sequentially from 15 breast fed and 15 bottle fed infants on five occasions between 6 days and 9 months of age. Total immunoglobulin concentrations of G, M, and A classes, and class specific antibodies to tetanus toxoid and a pool of commensal strains of Escherichia coli were measured by solid phase radioimmunoassay and expressed per milligram of total protein. There were significant differences between feeding groups, which changed with age. Total IgM and IgA concentrations and IgA antibodies to E. coli were higher in the saliva and nasal secretions of breast fed infants at 6 days. There followed a rapid increase in IgM and IgA concentrations in secretions from all infants, and between 6 weeks and 9 months concentrations were higher in the saliva (but not in the nasal secretions) of the bottle fed group. There were no significant differences between the feeding groups for total IgG, specific G, M, and A antibodies to tetanus toxoid, and G and M antibodies to E. coli. These results suggest that breast feeding enhances secretory immunity in the early neonatal period only. By 6 weeks, local antigens are the main source of stimulation for production of immunoglobulin in the respiratory mucosa and thus may be obscuring any additional stimulation by growth factors in breast milk.     

Presence of secretory IgA antibodies to an enteric bacterial pathogen in human milk and saliva.

The concept of a common mucosal immune system in man was tested by examining the concurrent presence of specific-secretory IgA (SIgA) antibodies in human milk and saliva from three groups of subjects: 64 Sri Lankan women living in Sri Lanka; 20 immigrant Asian women living in Birmingham (median duration of residence in the United Kingdom five years); and 75 Caucasian women living in Birmingham (controls). Enzyme linked immunosorbent assays (ELISA) were developed to detect enterotoxigenic Escherichia coli (ETEC) colonisation factor/1 (CFA/1) specific SIgA antibodies in milk and saliva. ETEC CFA/1 specific SIgA antibody activity was detectable in milk (37.5% and 25%) and saliva (42.1% and 35%) of Sri Lankan and immigrant Asian women, respectively, but not in any of the Caucasian controls. Eighty five point two per cent of subjects who were positive had specific antibodies detectable in both milk and saliva; 5% of all Sri Lankan women and 10% of all immigrant Asian women had detectable antibody only in saliva. These observations lend further strong support to the idea that a common mucosal immune system exists in man. The continuing presence of specific SIgA antibodies in Asian immigrants to previously encountered antigens suggests that there may be an ''immunological memory'' in the human secretory immune system.     

Local antibodies to alpha-casein and beta-lactoglobulin in the saliva of infants

Salivary antibodies were studied in 112 infants between 1 day and 8 yr of life. SIgA anticasein was present from birth in breast-fed and bottle-fed infants. Bottle-feeding resulted in significantly higher concentrations of SIgA anticasein at 3 wk to 3 months of life as compared to breast-feeding. Salivary anticasein declined toward the end of the 1st yr and was present in less than half of the children older than 1 yr. Salivary anti-beta-lactoglobulin was also present at birth in some infants. Levels increased slightly over the following 3 months but remained low. Only a minority of older children had this antibody in their saliva.     

Secretory immunoglobulin A in saliva of healthy children and children with airway diseases

Using the Elisa-Test of Dakopatts, Hamburg, described by Ishiguro et al and modified by us (Mikrotitration plates instead of tubes, blocking up free bonding capacities in the plates with 1% gel fluid, altered incubation periods) we determined secretory IgA (SIgA) in saliva samples of 376 infants and children. The probands could be divided in three groups: Group 1, serving as controls, consisted of 163 healthy children. Group 2 comprised 111 children suffering from acute infection of the respiratory tract. Group 3 consisted of 102 children with chronic airways diseases, in particular, asthma. In the healthy infants and children we found age dependent increases of SIgA until the age of 4 years. The median values amounted 16.7 (newborns), 59.2 (1st year), 118.2 (2nd year), 149.2 (3rd year), 185.5 (4th year), 159 (5th year) and 175.8 mg/l (5th-13th year). A similar age dependent increase of SIgA was evident in the saliva samples of children suffering from acute infections of the respiratory tract. In the children with chronic airways diseases there was only a slight increase of SIgA during the first 4 years (mean = 78.0-113.5 mg/l) and an abrupt (statistically significant) rise in the fifth year. The median value of SIgA was 216 mg/l in the children aged 5-13 years. Serum IgA along with salivary IgA were measured in 128 children (r = 0.40, p less than 0.001). 6 children had a complete IgA deficiency and 4 children an incomplete IgA deficiency, i.e. low secretory IgA levels in saliva (36.8-50.0 mg/l) and lacking IgA in serum (less than 14 mg/dl).(ABSTRACT TRUNCATED AT 250 WORDS)     

Regional deficiency of secretory IgA in a patient with combined immunodeficiency of the ADA deficient type.

The IgA system in a patient with SCID and ADA deficiency showed heterogeneity. Serum IgA and stool secretory IgA (SIgA) levels were normal, but with altered kappa/lambda and A1/A2 subclass ratios; IgA in saliva and urine was deficient. Amounts of secretory component were normal. Jejunal and rectal biopsies showed prominent lymphonodular hyperplasia, but no cells containing IgA. A normal serum IgA level therefore does not always predict an intact secretory IgA system.     

Enhanced fecal excretion of selected immune factors in very low birth weight infants fed fortified human milk

The amounts of lactoferrin, lysozyme, total IgA, secretory IgA (SIgA), and specific SIgA antibodies to a pool of Escherichia coli O antigens were measured in 96-h collections of feces obtained from 28 very low birth weight infants, 28-30 wk of gestation, studied at 2.5 and 6 wk of age. Eighteen of these infants were fed their mothers' milk fortified with fractions of skim and cream derived from pasteurized, lyophilized, mature human milk (FM) and 10 infants were fed commercial cow's milk-based formula. The concentrations of these selected immune factors in the FM and formula also were measured. Specific SIgA antibodies to E. coli O antigens were detected in the feces of 90% of the FM-fed infants, but in none of the feces of the formula-fed infants. The feces obtained from FM-fed infants had markedly greater quantities of lactoferrin (p less than 0.001), lysozyme (p = 0.006), and IgA (p less than 0.001) than those of cow's milk formula-fed infants. The concentrations of total and secretory IgA were correlated significantly (r = 0.88, p less than 0.001) and 95% of total IgA was SIgA. The fecal concentration of specific SIgA antibodies to E. coli O antigens in FM-fed infants correlated with the concentration of these antibodies in their milk (p less than 0.001). However, there were no direct relationships between the milk concentrations or the infant's intakes of the other selected immune factors and the excretion of these factors in the feces.(ABSTRACT TRUNCATED AT 250 WORDS)     

REGIONAL DEFICIENCY OF SECRETORY IgA IN A PATIENT WITH COMBINED IMMUNODEFICIENCY OF THE ADA DEFICIENT TYPE

Abstract. The IgA system in a patient with SCID and ADA deficiency showed heterogeneity. Serum IgA and stool secretory IgA (SIgA) levels were normal, but with altered K/ and A¹/A₂ subclass ratios; IgA in saliva and urine was deficient. Amounts of secretory component were normal. Jejunal and rectal biopsies showed prominent lymphonodular hyperplasia, but no cells containing IgA. A normal serum IgA level therefore does not always predict an intact secretory IgA system.     

High salivary secretory IgA antibody levels are associated with less late‐onset wheezing in IgE‐sensitized infants

To cite this article: Sandin A, Björkstén B, Böttcher MF, Englund E, Jenmalm MC, Bråbäck L. High salivary secretory IgA antibody levels are associated with less late‐onset wheezing in IgE‐sensitized infants. Pediatr Allergy Immunol 2011; 22 : 477–481. Low levels of secretory IgA (SIgA) and transient IgA deficiency have been associated with an increased risk for allergy, but data are conflicting. The aim was to assess the relationship between salivary SIgA antibody levels at 1 yr and wheezing at age four in a birth cohort, in particular the possible protective role of salivary SIgA in sensitized children. Saliva samples were obtained from all children (n = 67) with a positive skin prick test (SPT) at 1 yr and 212 children with a negative SPT. In all, 200 of these children responded to questionnaires at 4 yrs and 183 were skin prick tested at that age. The levels of salivary SIgA and salivary IgA antibodies to the most common food allergen egg and inhalant allergen cat were analyzed by ELISA. Serum was analyzed for IgE antibodies to egg and cat. Development of late‐onset wheezing was associated with low SIgA levels in children with positive SPT to at least one allergen both at 1 and 4 yrs of age (p = 0.04), as well as in children with circulating IgE antibodies to egg or cat at 1 yr (p = 0.02). None of nine persistently sensitized children with SIgA levels in the upper quartile developed wheezing, when compared to 10/20 children with lower levels (p = 0.01). Older siblings, more than three infections during infancy, at least one smoking parent, and male gender, were all associated with SIgA in the upper quartile. In conclusion, high levels of SIgA antibodies in sensitized infants were associated with significantly less late‐onset wheezing, supporting a protective role against development of asthmatic symptoms. Recurrent infections and other factors supporting an increased microbial pressure during infancy were associated with high levels of salivary SIgA.     

Pathologic and immune factors in thyroid disease.

Thyroid glands from 33 children with hyperthyroidism and nine with juvenile lymphocytic thyroiditis were examined histologically and for IgG, IgA, IgM, and C3 by immunofluorescent staining. There was no significant difference between glands with JLT and those with hyperthyroidism in the degree of lymphoid infiltration or lymphoid follicle formation. In thyroiditis there was no correlation between the degree of histologic abnormalities and the presence of immunofluorescent staining for IgG, IgM, or IgA. In hyperthyroidism there was a correlation between the degree of histologic abnormalities and the presence of IgG. In both groups of patients LI and LFF were distinctly more severe in glands positive for C3. Postsurgical hypothyroidism correlated with LI but not with LFF, IgG, or C3.     

Saliva IgM and IgA are a sensitive indicator of the humoral immune response to Escherichia coli O157 lipopolysaccharide in children with enteropathic hemolytic uremic syndrome

Saliva antibodies to Escherichia coli O157 were investigated as markers of the immune response in children with enteropathic hemolytic uremic syndrome (HUS). Paired serum and saliva samples were collected from 22 children with HUS during acute disease and convalescence and were tested for E. coli O157 lipopolysaccharide (LPS)-specific IgM and IgA antibodies by ELISA. Serum and saliva samples from 44 age-matched controls were used to establish the cut-off values. Elevated levels of IgM and/or IgA antibodies to O157 LPS were detected in saliva of 13/13 HUS patients with Shiga toxin-producing E. coli (STEC) O157 in stool culture and from 4 of 5 HUS patients in whom STEC were not detected. These results closely mirrored the results obtained with paired serum samples. In contrast, saliva and serum samples from four children with STEC isolates belonging to O-groups O26, O145 (n = 2), and O165 lacked detectable O157 LPS-specific antibodies. The specificity of the ELISA was confirmed by western blotting. In STEC O157 culture-confirmed cases, the sensitivity of the ELISA was 92% for saliva IgM and IgA, based on the first available sample, and 100% and 92%, respectively, when subsequent samples were included. The specificity was 98% for IgM and 100% for IgA. Children with E. coli O157 HUS demonstrate a brisk, easily detectable immune response as reflected by the presence of specific antibodies in their saliva. Saliva-based immunoassays offer a reliable, noninvasive method for the diagnosis of E. coli O157 infection in patients with enteropathic HUS.     

Antibody responses to parenteral and oral vaccines are impaired by conventional and low protein formulas as compared to breast-feeding

The vaccine response to poliovirus, diphtheria and tetanus toxoids in relation to protein intake was studied in infants, either breast-fed or given low (1.1 g/100 ml) or conventional (1.5 g/100 ml) protein formula. Serum, saliva and faeces antibodies were measured by the enzyme-linked immunosorbent assay. Neutralizing poliovirus antibodies were determined. The serum, saliva and faeces antibody responses in the two formula-fed groups of infants did not differ significantly, but for the low protein formula group which had significantly higher serum neutralizing titres to poliovirus after the second vaccine dose than the conventional formula group. However, the breast-fed group had significantly higher antibody levels than the two formula-fed groups together: serum IgG to diphtheria toxoid (p less than 0.01) and serum neutralization of poliovirus (p less than 0.001) at 21-40 months of age, saliva secretory IgA to tetanus (p less than 0.01), diphtheria toxoid (p less than 0.01) and poliovirus (p less than 0.05), as well as faecal IgM to tetanus toxoid (p less than 0.05) and poliovirus (p less than 0.01 and p less than 0.05) at 3 and 4 months of age. Breast-fed infants thus showed better serum and secretory responses to peroral and parenteral vaccines than the formula-fed, whether with a conventional or low protein content.     

Antibody Responses to Parenteral and Oral Vaccines Are Impaired by Conventional and Low Protein Formulas as Compared to Breast-feeding

ABSTRACT. The vaccine response to poliovirus, diphtheria and tetanus toxoids in relation to protein intake was studied in infants, either breast-fed or given low (1.1 g/100 ml) or conventional (1.5 g/100 ml) protein formula. Serum, salivá and faeces antibodies were measured by the enzyme-linked immunosorbent assay. Neutralizing poliovirus antibodies were determined. The serum, saliva and faeces antibody responses in the two formula-fed groups of infants did not differ significantly, but for the low protein formula group which had significantly higher serum neutralizing titres to poliovirus after the second vaccine dose than the conventional formula group. However, the breast-fed group had significantly higher antibody levels than the two formula-fed groups together: serum IgG to diphtheria toxoid (p<0.01) and serum neutralization of poliovirus (p<0.001) at 21-40 months of age, saliva secretory IgA to tetanus (p<0.01), diphtheria toxoid (p<0.01) and poliovirus (p<0.05), as well as faecal IgM to tetanus toxoid (p<0.05) and poliovirus (p <0.01 and p <0.05) at 3 and 4 months of age. Breast-fed infants thus showed better serum and secretory responses to peroral and parenteral vaccines than the formula-fed, whether with a conventional or low protein content.     

Presence of non-maternal antibodies in newborns of mothers with antibody deficiencies.

To explain the mechanism for induction and production of specific antibodies found in the newborn already at birth, without previous known exposure to the antigen, we chose a model that presumably excluded the possibility of specific antibodies being transferred from the mother to the fetus. Specific IgG, IgA, and IgM antibodies against Escherichia coli and poliovirus antigens were determined with ELISA in serum, saliva, and amniotic fluid from hypogammaglobulinemic and IgA-deficient mothers as well as in cord serum, saliva, and meconium from their offspring. All the mothers lacked IgA and some also lacked IgM antibodies, which were found in their healthy newborns. The amniotic fluid from a hypogammaglobulinemic mother lacking IgA contained small amounts of IgA antibodies, which were also found in the neonate, suggesting a fetal origin. There was evidence for the presence of antiidiotypic antibodies to poliovirus in the cord sera. We propose that idiotypic and/or antiidiotypic IgG antibodies transferred via the placenta from the mother to the fetus can initiate specific immune responses seen in the newborn. Thus, it may be that transplacental IgG not only passively protects the newborn, but also actively primes the fetus during fetal life via its content of idiotypic and/or antiidiotypic antibodies.     

Comparison of Serum and Salivary Antibodies in Children Vaccinated with Oral Live or Parenteral Inactivated Poliovirus Vaccines of Different Antigen Concentrations

ABSTRACT. A new antigen-rich inactivated poliovirus vaccine (IPV) in ordinary (IPV1), double (IPV2) and quadruple (IPV4) antigen concentrations was given in 2 doses to 6 and 18 week old Pakistani infants. The immune responses to poliovirus types 1 and 3 were compared to those in infants given three doses of oral poliovirus vaccine (OPV) at 6, 12 and 18 weeks of age. Enzyme-linked immunosorbent assay, ELISA, was used to estimate IgC and IgA in serum and secretory IgA (SIgA) in saliva. Two to three years later, a follow-up of the serum antibody response was carried out in the same infants using a microneutralization test. Serum IgG antibody responses to poliovirus type 1 antigen after two doses of IPV1, IPV2 and IPV4 were not significantly higher than the response after three doses of OPV at 21 weeks of age ( p > 0.05). The serum IgC responses to poliovirus type 3 were similar to those against type 1 in all the groups. Mean neutralizing antibody titres to poliovirus type 1 was significantly higher in the IPV2 group than the rest of the groups ( p <0.01). For type 3, these titres were highest but not significantly, in the IPV4 group ( p > 0.05). This study shows that two doses of a new antigen-rich IPV can give similar immediate serum antibody responses as OPV but higher late responses. SIgA antibodies in saliva were more efficiently induced by OPV after three doses than after 2 doses of IPV ( p <0.05).     

Comparison of serum and salivary antibodies in children vaccinated with oral live or parenteral inactivated poliovirus vaccines of different antigen concentrations.

A new antigen-rich inactivated poliovirus vaccine (IPV) in ordinary (IPV1), double (IPV2) and quadruple (IPV4) antigen concentrations was given in 2 doses to 6 and 18 week old Pakistani infants. The immune responses to poliovirus types 1 and 3 were compared to those in infants given three doses of oral poliovirus vaccine (OPV) at 6, 12 and 18 weeks of age. Enzyme-linked immunosorbent assay, ELISA, was used to estimate IgG and IgA in serum and secretory IgA (SIgA) in saliva. Two to three years later, a follow-up of the serum antibody response was carried out in the same infants using a microneutralization test. Serum IgG antibody responses to poliovirus type 1 antigen after two doses of IPV1, IPV2 and IPV4 were not significantly higher than the response after three doses of OPV at 21 weeks of age (p greater than 0.05). The serum IgG responses to poliovirus type 3 were similar to those against type 1 in all the groups. Mean neutralizing antibody titres to poliovirus type 1 was significantly higher in the IPV2 group than the rest of the groups (p less than 0.01). For type 3, these titres were highest but not significantly, in the IPV4 group (p greater than 0.05). This study shows that two doses of a new antigen-rich IPV can give similar immediate serum antibody responses as OPV but higher late responses. SIgA antibodies in saliva were more efficiently induced by OPV after three doses than after 2 doses of IPV (p less than 0.05).     

Breastfeeding stimulates total and cow's milk-specific salivary IgA in infants

Breastfeeding may increase the rate of mucosal maturation and IgA production. We sought to determine the effect of breastfeeding vs. formula-feeding on the maturation of oral mucosa by measuring the salivary total antibodies and cow's milk protein-specific IgA. Fifty-eight saliva samples were collected from 39 healthy, full term infants. At the age of 3 months (n = 25) eight infants received only breast milk and seventeen formula (cow's milk based n = 10, hydrolysed n = 7) and breast milk; and at the age of 6 months (n = 33) eleven received breast milk, seventeen formula and breast milk and five were not breastfed any more (cow's milk based n = 14, hydrolysed n = 8). Total IgA, IgG, IgM and protein, and β-lactoglobulin specific IgA were measured from saliva with enzyme-linked immunoassay (ELISA). The antibody results were proportioned to total protein. No differences in antibody levels between the feeding groups were found at 3 months of age. At 6 months, total IgA, total IgM and β-lactoglobulin-specific IgA were higher among the breastfed infants compared to those receiving formula as supplement to breast milk or not breastfed any more (breast milk vs. any formula p = 0.029, p = 0.015, p = 0.058; breast milk vs. cow's milk formula p = 0.025, p = 0.044, p = 0.038). To conclude, breastfeeding stimulated the mucosal immune system to produce IgA to saliva, which is a marker for immunological maturation and likely provides protection against environmental antigens.