Influence of type of feeding on lymphocyte function and development of infantile allergy

Select human milk oligosaccharides directly modulate peripheral blood mononuclear cells isolated from 10-d-old pigs

Infant formulas lack the complex mixture of oligosaccharides found in human milk. These human milk oligosaccharides (HMO) may be pivotal to the development of the neonatal immune system. Few comprehensive analyses of the effects of HMO on immune cells from neonates have been undertaken. Herein, the direct effects of HMO on immune cells were analysed ex vivo. Peripheral blood mononuclear cells (PBMC) isolated from 10-d-old sow-reared (SR) or colostrum-deprived formula-fed (FF) pigs were stimulated for 72 h with single HMO, mixtures of single HMO or a complex mixture of HMO isolated from human milk (iHMO). T-cell phenotype, cytokine production and proliferation were measured by flow cytometry, immunoassay and [³H]thymidine incorporation, respectively. Stimulation with HMO had direct effects on PBMC. For instance, cells stimulated with iHMO produced more IL-10 than unstimulated cells, and cells stimulated with fucosylated HMO tended to proliferate less than unstimulated cells. Additionally, co-stimulation with HMO mixtures or single HMO altered PBMC responses to phytohaemagglutinin (PHA) or lipopolysaccharide (LPS) stimulation. Compared with PBMC stimulated with PHA alone, cells co-stimulated with iHMO and PHA proliferated more and had fewer detectable CD4⁺CD8⁺ T cells. Compared with PBMC stimulated by LPS alone, cells co-stimulated with a mixture of sialylated HMO and LPS proliferated more and tended to have fewer detectable CD4⁺ T cells. Differences in the baseline responses of PBMC isolated from the SR or FF pigs were observed. In summary, HMO directly affected PBMC populations and functions. Additionally, ex vivo measurements of PBMC phenotype, cytokine production and proliferation were influenced by the neonate's diet.

Dietary nucleic acids promote a shift in Th1/Th2 balance toward Th1-dominant immunity

BACKGROUND

Dietary sources of nucleic acids and their relative components are known to affect host immune function; however, it has not yet been clarified whether such dietary nucleic acids influence the pathogenesis of allergic reaction.

OBJECTIVE

The purpose of this study is to elucidate the effect of dietary nucleic acids on Th1/Th2 balance.

METHODS

Both human flora-associated and specific pathogen-free BALB/c mice were maintained on either nucleic acid-free, or -supplemented diets. The effects of nucleic acids on both in vivo antibody levels and in vitro splenocyte cytokine production were compared using these mice.

RESULTS

Supplementation of nucleic acids caused a reduction in the serum antibody levels of total IgM, IgG, IgG1, and IgE in the human flora-associated mice without affecting the composition of intestinal flora. In contrast, there was no significant difference of the serum IgG2a levels between nucleic acid-free and -supplemented mice. Such a phenomenon as that, the supplementation of dietary nucleic acids reduces the serum IgE or IgG1 levels, but not the IgG2a level, was also seen in the specific pathogen free mice. Moreover, when the mice were systematically challenged with ovalbumin, the supplementation of nucleic acids also suppressed the serum ovalbumin-specific IgE and IgG1 antibody levels as well as in vitro IL-4 and IL-10 secretion, while enhancing both the serum ovalbumin-specific IgG2a antibody levels and in vitro IFN gamma secretion.

CONCLUSION

These results suggested that dietary nucleic acids may play an important role in promoting a shift in Th1/Th2 balance toward Th1-dominant immunity.

Myths and facts about breastfeeding: does it prevent later atopic disease?

Exclusive human milk feeding during the first 6 months of life, with delayed introduction of solids, is the recommended feeding for human infants. Human milk reduces the incidence and morbidity related to infection and allergy to cow's milk proteins. Dietary maternal restrictions during (late) pregnancy or lactation cannot be recommended, but may be advised in special cases. A maternal elimination diet seems more effective if associated with environmental hypoallergenic intervention(s). Milk from mothers consuming cow's milk proteins contains small amounts of beta-lactoglobulin, which appear to introduce in the majority of infants both atopic and non-atopic tolerance rather than sensitization. However, it is uncertain whether breastfeeding also reduces the incidence of later atopic disease, since its aetiology is multifactorial.

Infant feeding history shows distinct differences between Swedish celiac and reference children

Infant feeding history was investigated in 72 celiac and 288 age-matched reference children in a retrospective questionnaire study. The reply rate was 100% in celiac and 91.6% in reference children. The celiac children were breast-fed for a significantly shorter time than reference children, and they were less often breast-fed at the introduction of gluten. The age of the children at gluten introduction was similar, but the celiac children were significantly more often introduced by a gluten-containing follow-up formula, while the reference children more often started on a gluten-containing porridge. The results can be interpreted in two ways. First, it could be argued that breast milk per se protects against symptoms of celiac disease in childhood. It could, however, also be claimed that breast-feeding merely modulates the gluten introduction, causing a less abrupt introduction of gluten in the baby diet and thereby fewer overt symptoms of the disease.

[Milk feeding of infants and cow's milk protein hypersensitivity]

BACKGROUND

Cow milk protein intolerance (CMPI) is characterized by a wide range of symptoms and signs affecting the gastro-intestinal tract, the respiratory system and the skin. A better definition, a stricter application of diagnostic criteria and critical evaluation of certain immunologic correlates can contribute to a better understanding and preventive treatment of this entity.

POPULATION AND METHODS

Two hundred-seventeen infants with CMPI seen between January 1980 and December 1993 were included in the study. They were classified into two groups: 1) acute reaginic CMPI (type I): 125 infants and 2) CMP enteropathy or colitis (type III or IV): 92 infants, according to classical diagnostic criteria. Careful investigation concerning the type of milk feeding (breast or artificial) proposed prior to clinical manifestations was performed.

RESULTS

Among the 125 infants (aged 3 to 20 weeks) with acute reaginic CMPI, 121 (97%) had been breast-fed with a sudden weaning; 30 of these infants had also received one to three formula bottles during the first 3 days of life and 14 certainly had not received such formula bottles. Among the 92 infants with CMPI, type III or IV, 33 (38%) had been exclusively breast-fed, a figure quite similar to the breast feeding incidence in our region.

CONCLUSIONS

These results clearly show the importance of breast-feeding in the personal history of CMPI. Acute reaginic type of CMPI is favored by early ingestion of formula bottles in breast-fed infants and by early sudden weaning. Hypoallergenic formula in five cases was unable to protect infants against further allergic manifestation.

Allergic symptoms up to 4-6 years of age in children given cow milk neonatally. A prospective study

In a previously published prospective study, we followed the development of allergic symptoms in term infants with a slightly reduced birthweight (-1 SD to -2 SD). These children received, according to local routine, early feeding with cow milk formula in order to diminish such neonatal problems as hypoglycemia and hyperbilirubinemia. Of 216 infants 207 were observed for allergic symptoms up to 18 months of age. One group (F) received cow milk formula during the first days of life before the mother's breastmilk production started and was then breastfed; the other (B) was not given any formula before normal breastfeeding started. Unexpectedly, we found fewer allergic symptoms, in particular allergic skin problems, in the group fed cow milk, the difference being concentrated to children with a family history of allergic symptoms. At 5 years of age 183 of the 207 children have been reinvestigated. Mild symptoms of allergy (suspected and obvious) were found in 22% (F) and 27% (B) respectively (NS). Moderate and severe symptoms of allergy (obvious) were found in 4.2% (F) and 4.5% (B). In the subgroup with a double family history of allergic symptoms, 28% (7/25, F) and 59% (10/17, B) had symptoms of allergy (p less than 0.05). This difference was even more pronounced when laboratory tests in favour of atopic diagnosis were included, 14% (F) and 53% (B) respectively (p less than 0.05). Thus at 5 years we still find a significantly lower frequency of allergic symptoms in the subgroup fed cow milk formula early with a family history of allergic symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Breast feeding modifies production of SIgA cow's milk-antibodies in infants

One hundred and fifty-eight healthy mature newborns were divided into 3 groups according to their risk of allergy: Group A, no risk (n = 62), group B, low risk (n = 30) and Group C, high risk (n = 66). Saliva was collected at birth and after 3 and 6 months. SIgA anti-casein and anti-beta-lactoglobulin were determined by a direct ELISA technique. The highest concentrations of secretory antibodies were measured after birth. After 3 months, breast fed infants had lower salivary SIgA anti-casein concentrations than the group receiving cow's milk (p less than 0.01). The effect of breast-feeding was seen even after a nursing period of only 3 weeks. Infants without risk of allergy fed cow's milk exclusively had higher SIgA anti-casein (p less than 0.03) and anti-beta-lactoglobulin concentrations than low risk infants at the age of 6 months. These data show a modifying effect of breast feeding on salivary SIgA production against cow's milk protein.

Infant feeding effects on flow cytometric analysis of blood

Flow cytometric analysis was performed on purified mononuclear cells isolated from whole blood samples of 11 adults, 7 breast-fed (BF) infants and 11 formula-fed (FF) infants, mean ages 34.2 +/- 4.3 years, 6.3 +/- 1.3 months, and 6.2 +/- 1.2 months, respectively. Infants were receiving at least 70% of calories from formula or breast milk. Infant mononuclear cell populations contained a higher percentage of lymphocytes and a lower percentage of monocytes compared with adults. Within the lymphocyte population, infants had a higher CD4+/CD8+ ratio (T helper-inducer/T cytotoxic-suppressor), a higher percentage of CD19+ (pan B) and CD4+ cells, and a lower percentage of CD8+ and CD16+ (natural-killer) cells compared with adults. CD3+ (pan T) and CD4+ lymphocyte percentages were higher and CD19+ lymphocyte percentages were lower in FF compared with BF infants. Although sample size is small, our data indicate that diet may influence lymphocyte subset distribution during infancy when the majority of calories is derived from infant formula or human milk.

Food allergy: facts and fiction

Hypersensitivity reactions to dietary products are especially common in the pediatric population, yet food allergy as a distinct clinical entity remains poorly defined. The clinicopathologic features of this syndrome can vary considerably from patient to patient; no reliable diagnostic laboratory tests are available, and some of the treatment regimens are controversial. The pathogenesis of this condition is not well understood. An important factor is the role of the intestinal mucosal barrier in the regulation of uptake of dietary antigen from the intestinal tract. Recently, significant differences have been observed between the features of the immature newborn and the mature adult intestinal mucosal barriers. These findings may be of fundamental importance to the pathogenesis of food allergy and are currently an area of intense research.

Does breast feeding help protect against atopic disease? Biology, methodology, and a golden jubilee of controversy

To help shed some light on the 50-year-old controversy concerning the possible protective effect of breast feeding on subsequent atopic disease, I developed 12 standards pertaining to both biologic and methodologic aspects of exposure (infant feeding), outcome (atopic conditions), and statistical analysis for studies of atopic eczema, asthma, allergic rhinitis, cow milk allergy, and other food allergy. Among the published studies on atopic eczema, the nine claiming a protective benefit of breast feeding performed less well than the 12 not making such a claim on "methodologic" standards relating to strict diagnostic criteria and blind ascertainment of outcome. The positive studies were somewhat stronger, however, on the "biologic" standards bearing on sufficient duration and exclusivity of breast feeding and on separate analysis of children at high risk. For the other atopic conditions, there were no important differences between positive and negative studies. In few negative or positive studies was there adequate control for confounding variables or examination of potential benefits relating to the severity or age at onset of atopic disease. To avoid another 50 years of unresolved controversy, future studies should improve both the biologic and methodologic aspects of their design and analysis.

Development of atopic disease after early administration of cow milk formula

We prospectively studied the incidence of atopic disease in healthy term infants with a birth weight between -1 and -2 SD who were fed a cow milk formula during the first few days of life. A total of 216 infants were randomized to receive either early feeding with formula before normal breastfeeding was started (n = 112) or "normal feeding" with breastmilk (n = 104). Symptoms of allergy developed in 18% of the infants before 18 months of age in the formula fed group, as compared to 33% in the breastfed group (P less than 0.05). The difference was confined to the group of infants with a history of allergy in two family members. Thus, 11% of the formula-fed infants developed allergy symptoms, as compared to 61% of the control infants (P less than 0.01). Our study implies that early feeding during the first days of life with a cow milk formula, before the introduction of breastmilk, may reduce the incidence of allergy symptoms before 18 months of age in infants with a family history of allergy.

Presence of IgE suppressor factors in human colostrum

In spite of intensive investigations, the ability of breast feeding to delay and to attenuate atopic diseases in children remains debatable. This study documents a mechanism whereby breast feeding might interfere with the synthesis of IgE by breast-fed infants. Indeed, we show that colostrum contains IgE-binding factors (IgE-BF) capable of suppressing the in vitro synthesis of human IgE. Colostrum obtained from 15 donors was successively depleted of lipids and casein, filtered through Amicon XM50 membrane (mol. mass cut-off 50 kDa) and lyophilized. IgE-BF was demonstrated in such preparations by two different approaches, i.e. a classical rosette inhibition assay and Western blot analysis. In the first instance, lyophilized preparations of colostrum inhibited the binding of IgE-coated bovine erythrocytes to IgE recovered on the surface of RPMI 8866 lymphoblastoid cells. The rosette-inhibiting activity could be absorbed on IgE- but not on IgG-Sepharose 4B and it could be recovered in the eluate of IgE-Sepharose 4B. The molecular mass of IgE-BF was comprised between 10 to 20 kDa as estimated by gel filtration through a calibrated Sephadex G-75 column. After fractionation on 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transfer to nitrocellulose membrane, colostrum displayed one band of 14 kDa and reacted with radiolabeled IgE but not with IgG nor IgM. This 14-kDa band could be removed by absorbing colostrum with IgE- but not with IgG-Sepharose 4B. Most importantly, the colostrum IgE-BF suppressed the spontaneous in vitro synthesis of IgE by B lymphocytes derived from allergic donors without altering the production of IgM.

Humoral immunity to dietary antigens in atopic dermatitis. II. Analysis of IgE and IgG subclass antibodies

IgG subclass antibodies to two dietary antigens, ovalbumin (OA) and beta-lactoglobulin (BLG) were measured with quantitative ELISA-techniques in 16 patients with atopic dermatitis (AD) (6-21 years old) and closely matched controls. In addition, IgE-antibodies to OA, BLG and milk were determined with RAST. IgG subclass antibodies were frequently detected in IgG1 and IgG4 for both AD-patients and controls, quantitatively dominated by IgG4. The IgG4 anti-BLG antibody levels were significantly higher (P less than 0.001) in AD-patients (median: 1.1 microgram/ml, range: 0-24.0 microgram/ml) than in controls (median: 0.05 microgram/ml, range: 0-1.05 microgram/ml). No relation was found between IgG4 anti-BLG antibody levels, levels of IgE antibodies to milk or BLG, or severity of disease.

Human milk stimulates B cell function

The effect of human milk on B cell function was studied by using murine spleen cells stimulated with suboptimal doses of lipopolysaccharide. Cell free, defatted, filtered colostrum as well as mature breast milk showed an enhancing effect on B cell proliferation and generation of antibody secretion, but this was not seen with formula milk. The activity was heat sensitive and resisted overnight dialysis. It is suggested that this could represent an important immunological mechanism explaining the anti-infectious properties of breast milk.

Breast milk cell supernatants from atopic donors stimulate cord blood IgE secretion in vitro

Breast milk cell culture supernatants from atopic mothers (nineteen) were compared by ELISA with normal breast-feeding controls (twenty-one) for regulation of cord blood lymphocyte IgA and IgE secretion in vitro. A minority of atopic (five out of nineteen) and normal (three out of twenty-one) cell supernatants stimulated cord blood lymphocyte IgA release to the same extent. The others were inactive. Stimulation was not related to breast milk cells donor atopic history or cord blood lymphocyte atopic heredity. In contrast, 70% of atopic milk cell supernatants stimulated cord blood lymphocyte cultures to form IgE (means +/- s.d. = 2070 +/- 2240 pg/culture) while stimulatory supernatants (24%) from normal donors resulted in less lymphocyte IgE release (means +/- s.d. = 680 +/- 490 pg/culture) (p less than 0.001). These differences did not correlate with breast milk cell supernatant IgE concentrations, cord blood donor serum IgE levels or atopic heredity.

Does infant feeding affect the risk of allergy?

For nearly 50 years the hypothesis has been debated that withholding cows' milk from babies reduces the risk of allergic disease. Numerous studies have been conducted of varying design, size, and quality, and with conflicting results. Evidence tends to favour the hypothesis, but the only firm conclusion that can be drawn is that random controlled trials with blind assessment are needed to settle the issue.

Breast feeding, eczema, asthma, and hayfever

The association of breast feeding with rates of atopic illness during the first five years of life was assessed in a national study of 13 135 children studied during the first week and at age 5 years. Eczema was reported more often in children who had been breast fed; this relationship persisted even after allowance was made for social and family factors influencing the likelihood both of breast feeding and of eczema; the other factors most significantly associated with rates of eczema were parental history of eczema or asthma and advantaged family socioeconomic status. A similar, but less pronounced, positive association of breast feeding with reported hayfever became non-significant after adjustment for intervening factors. Rates of reported asthma were not influenced by breast feeding. "Any wheezing" including asthma was reported more often in children who had not been breast fed, but this association disappeared after adjustment for parental asthma and maternal smoking. Breast feeding does not appear to protect against these atopic diseases. The positive association with reported eczema might relate to accuracy of diagnosis or to associated influences not considered in the analysis; alternatively, it might be due to (recent) environmental contaminants crossing in breast milk, causing eczema in the child.