T-lymphocyte subsets, thymic size and breastfeeding in infancy

We followed the changes in concentration of T-lymphocyte subsets (CD4+ and CD8+ cells) in peripheral blood and thymus size during infancy. Previous studies have found increased thymus size in breastfed infants. The present study analyzed the association between breastfeeding and the number of CD4+ and CD8+ cells. Two different populations of infants between birth and 1 year of age were examined. Study Group I: infants with a variable duration of breastfeeding. Study Group II: long-term breastfed infants. In both groups a correlation was found between CD8+ cells and the thymic index at 10 months of age. In Group I, infants still breastfed at the 8-month examination had a higher CD8% than formula-fed infants (p = 0.05), and infants breastfed at the 4-month examination had a higher CD4% at 10 months of age (p= 0.03). Group II showed an increase in the absolute number of CD4+ and CD8+ cells from 8 to 10 months of age; and a positive correlation between the number of breastfeedings per day at 8 months of age, and an increase in CD4+ cells from 8 to 10 months of age (p <0.01). In conclusion, a correlation was found between thymus size and CD8+ cells. Breastfeeding might have both a current and long-term immune-modulating effect on the developing cellular immune system.     

Plasma lipids and apolipoproteins in breastfed and formula-fed Swedish infants

This study was carried out to compare plasma lipid pattern in breastfed and formula-fed infants and the effects of exchanging breast milk for formula and of introducing weaning foods. Healthy infants, exclusively breastfed at least until 3 mo, were at this age randomly assigned to infant formulas with similar fat composition. Formula was gradually introduced when breastfeeding was discontinued. One group continued to breastfeed beyond 6 mo of age. All infants received the same weaning foods and were studied between 3 and 12 mo of age. Decreased plasma concentrations of total and low-density lipoprotein cholesterol (TC, LDL-C), apolipoprotein B (apo B) and A1 (p < 0.001), and of high-density lipoprotein cholesterol (p < 0.05) were found when breast milk was exchanged for formula before 6 mo. At this age plasma TC, LDL-C and apo B were lower in formula-fed than in breastfed infants (p < 0.001). These plasma lipids then increased (p < 0.01) when the intake of formula decreased and that of weaning foods increased. However, plasma TC and/or LDL-C remained lower at 12 mo in formula-fed than in breastfed infants (p < 0.05). Our results indicate that the plasma lipid profile of infants is highly responsive to the dietary nutrient intake, as indicated by the decrease in plasma lipids and apolipoproteins when breast milk was exchanged for formula and by the increase in these concentrations when the intake of weaning foods gradually increased.     

Hypoantigenic (HA) milk formula and blood cholesterol level in infants at 3 months of age

A preliminary observation is reported concerning total and high-density lipoprotein blood cholesterol levels in 36 infants at 3 months of age fed with a hypoantigenic milk formula. The values are compared with those of 66 breastfed and 76 conventional formula-fed infants. Total and high-density lipoprotein-cholesterol levels in hypoantigenic formula-fed infants (152 and 65. 7 mg dl^-1, respectively) were comparable to those of breastfed infants (148 and 61. 8 mg dl^-1) and significantly ( p <0. 05) higher than those of conventional formula-fed infants (130 and 42. 5 mg dl^-1).     

Thymic size in uninfected infants born to HIV-positive mothers and fed with pasteurized human milk

AIM: To examine the size of the thymus in uninfected infants born to HIV-positive mothers and to study the effects of feeding by human donor milk on the size of the thymus in these infants. METHODS: The absolute and relative thymic size was assessed by sonography as thymic index (Ti), and the Ti/weight-ratio (Ti/w) at birth and at 4 mo of age in 12 healthy uninfected infants born to HlV-infected mothers. All infants were exclusively fed pasteurized donor milk. The results were compared with those obtained from a previous cohort of exclusively breastfed, partially breastfed and exclusively formula-fed infants. RESULTS: At birth the Ti was reduced in infants born to HIV-infected mothers in comparison with that in control infants but this difference disappeared when their birthweights were taken into consideration (Ti/w-ratio). At 4 mo of age the geometric mean Ti of infants fed donor milk was 23.8 and the mean Ti/w-ratio was 4.2. Compared with those of exclusively breastfed infants, the Ti and Ti/w-ratio of infants fed donor milk were significantly reduced (p < 0.01). The Ti/w-ratio increased in donor-milk-fed infants compared with that in the formula-fed infants (p = 0.02). CONCLUSION: At birth the size of the thymus was smaller in uninfected infants of HIV-positive mothers compared with infants of HIV-negative mothers but when birthweight was taken into account this difference disappeared. Feeding by human donor milk seemed to result in an increased size of the thymus at 4 mo of age compared with thymic size in infants that were exclusively formula fed.     

Leptin levels in breast-fed and formula-fed infants

Aim: Leptin, a hormone that regulates food intake and energy metabolism, is present in breast milk and thus may be involved in body composition differences between breastfed and formula-fed infants. The aim of this study was to evaluate whether diet and gender affect plasma leptin concentration in breastfed and formula-fed infants during the first months of life. Methods: Anthropometric and bioelectrical impedance measurements [total body water (TBW) calculated with the Fjeld equation] were made and venous blood plasma samples were analysed for leptin concentration in healthy, exclusively breastfed or formula-fed Italian infants in the first year of life. Infants were subdivided in two ways: three groups (periods) in relation to age, and five groups in relation to weight. Results: The average serum concentration of leptin was 7.35 ng ml -1 . Serum leptin values were higher in breastfed than in formula-fed infants. Breastfed infants in group 1 had a statistically higher serum leptin concentration (2500-3749 g). There were no significant differences in anthropometric measurements, body mass index or skinfold thickness between breastfed and formula-fed infants. In the periods I and II, breastfed infants had a significantly higher TBW than formula-fed infants. Males had a significantly higher TBW than females in periods I and II. Breastfed infants in group 2 (3750-4999 g) had a significantly higher TBW than formula-fed infants.

Conclusion: The data on TBW, weight and skinfold thickness suggest that the higher leptin concentration observed in breastfed infants in the first months of life may be due not only to adipose tissue production but also to human milk.     

T淋巴细胞亚群及过敏原与婴幼儿肺炎支原体感染伴喘息的关系

目的 分析肺炎支原体 （MP）感染伴喘息婴幼儿的T淋巴细胞亚群表达及过敏原筛查情况。方法 流式细胞仪检测354例MP感染伴喘息婴幼儿 （MP喘息组）、336例MP感染不伴喘息婴幼儿 （MP非喘息组）、277例反复喘息患儿 （反复喘息组）的外周血T淋巴细胞亚群表达,同时进行过敏原检测。结果 MP喘息组和反复喘息组的CD3+及CD3+CD8+淋巴细胞百分比均低于MP非喘息组 （P < 0.05）;MP喘息组和MP非喘息组的CD3+CD4+淋巴细胞百分比均高于反复喘息组 （P < 0.05）;MP喘息组和反复喘息组的CD3-CD19+及CD19+CD23+淋巴细胞百分比均明显高于MP非喘息组 （P < 0.05）,以反复喘息组最高 （P < 0.05）。食入性过敏原检测总阳性率 （30.3%）高于吸入性过敏原 （14.7%）,P < 0.05;反复喘息组、MP喘息组的食入性和吸入性过敏原阳性率均高于MP非喘息组,以反复喘息组最高 （P < 0.05）。结论 T淋巴细胞亚群紊乱、过敏体质在MP感染伴喘息的婴幼儿发病起着重要作用。     

Plasma total homocysteine increases from day 20 to 40 in breastfed but not formula-fed low-birthweight infants

Homocysteine is an intermediate in the folate cycle and methionine metabolism. This study investigated whether formula-fed infants have different plasma total homocysteine to their breastfed counterparts, and during what period any difference developed. Plasma total homocysteine was determined in 53 formula-fed and 15 breastfed healthy low-birthweight babies (< or = 2500 g) around days 10, 20 and 40. Total homocysteine was also measured in human milk. Mean +/- SD plasma total homocysteine levels (micromol l(-1)) at days 10, 20 and 40 were 6.4 +/- 2.6, 6.7 +/- 2.4 and 9.1 +/- 2.4 (breastfed), and 7.5 +/- 3.2, 7.3 +/- 2.1 and 7.4 +/- 1.6 (formula-fed). Homocysteine of breastfed babies at day 40 was higher than that of breastfed babies at day 20 (p < 0.0001), and that of formula-fed counterparts at day 40 (p = 0.002). Homocysteine correlated negatively with formula (day 10) and breast milk (day 40) volume intakes. Median (range) homocysteine in 12 mature human milk samples was 0.30 (not detectable to 0.7) micromol l(-1). Conclusion: Increasing plasma total homocysteine in breastfed babies to higher levels compared with formula-fed babies may be caused by a gradually developing suboptimal B-vitamin status in lactating women.     

Serum bilirubin levels at 72 hours by selected characteristics in breastfed and formula-fed term infants delivered by cesarean section

The present multicenter study analysed the relative impact of maternal and infant factors on serum bilirubin levels at 72 +/- 12 h in exclusively breastfed vs formula-fed term infants. End-tidal carbon monoxide levels corrected for ambient air (ETCOc), an index of bilirubin production, were measured in exclusively breastfed (B = 66) or formula-fed (F = 210) term infants at 2-8 h of age. Inclusion criteria included cesarean section to ensure a 3 d hospitalization, birthweight > or = 2,500 g, gestational age >37 wk and absence of any illness. The ETCOc for B infants and F infants did not differ significantly (1.3 +/- 0.7 ppm vs 1.3 +/- 0.8 ppm). The serum bilirubin level at 72 +/- 12 h was significantly higher in B infants than in F infants (8.5 +/- 3.4mg dl(-1) vs 6.7 +/- 3.4mg dl(-1) p < 0.001), as was the percentage weight loss from birthweight. Serum bilirubin levels were significantly higher in infants who were male, who did not have meconium-stained amniotic fluid, and in those whose mothers were insulin-dependent diabetics or hypertensive. There was no difference between groups in the need for phototherapy or exchange transfusion. CONCLUSION: Although higher bilirubin levels were observed in group B at 72 +/- 12 h compared with group F, this finding was not of clinical or therapeutic consequence in this study. The lack of difference in ETCOc between the groups may be a factor of the timing of ETCOc measurement in this study, or may suggest that early increased bilirubin production is not a significant contributor to jaundice observed in exclusively breastfed infants. Key words: bilirubin, breastfeeding, jaundice     

Interferon-γ production by cord-blood mononuclear cells is reduced in newborns with a family history of atopic disease and is independent from cord blood IgE-levels

For newborn children both elevated serum IgE levels in the cord blood and a positive family history of atopic disease have been shown to be risk factors for the manifestation of atopic diseases. In adult patients with atopic dermatitis, in vitro interferon-γ (IFN-γ) production is reduced and a negative correlation with serum IgE levels has been shown. We have now raised the question if newborn infants at risk for the development of atopic disease have similar abnormalities of cytokine production at birth. In vitro production of interleukin 2, interleukin 6 and interferon-γ by peripheral blood mononuclear cells was measured in 53 newborns: 21 had cord blood IgE levels above 0. 9 kU/1, 21 had a positive family history, 7 had both elevated IgE and a positive family history; 18 newborns with no identitiable risk for atopic disease served as controls. Umbilical cord blood mononuclear cells were stimulated with PHA or monoclonal antibody OKT3. In vitro production of interleukin 2 and 6 was comparable in all groups. Compared to controls IFN-γ production of peripheral mononuclear cells (PBMC) from newborns with elevated cord blood IgE was not different, but PMBC from newborns with a familial risk showed a significant decrease in PHA induced IFN-γ production (p < 0.005, U-test). No correlation between umbilical cord blood IgE and diminished IFN-γ production was found in newborns with or without a positive family history. We conclude that immunoregulatory abnormalities in newborns of atopic families are detectable already at birth and are unrelated to cord blood IgE.     

Serum cholesterol ester fatty acids in 7- and 13-month-old children in a prospective randomized trial of a low-saturated fat, low-cholesterol diet: the STRIP baby project

To evaluate changes that occur in serum cholesterol ester fatty acid composition during the transition from typical infant feeding to a more adult type of nutrition, this study compared the effects on serum cholesterol ester fatty acids of breast milk or formula at the age of 7 mo with effects caused by 6-mo dietary intervention in 137 children. The intervention [Special Turku coronary Risk factor Intervention Project for children (STRIP baby project)] aimed at a reduction of saturated fat intake to 10% of energy after the age of 1 y without purposefully influencing total fat intake. Nutrient intakes were calculated from 3-d food records. At the age of 7 mo, i.e. before dietary education began, milk type markedly influenced dietary and serum cholesterol ester fatty acid composition (mean serum cholesterol ester 16:0 in breastfed vs formula-fed infants, 13.7% vs 12.0%, respectively, p < 0.001; serum cholesterol ester 18:2n-6 50.6% vs 57.6%, p < 0.001). At the age of 13 mo the calculated fat intake of the intervention and control children differed markedly but serum cholesterol ester fatty acid compositions in all children resembled closely those measured in 7-mo-old breastfed infants, e.g. at the age of 13 mo the relative proportions of 18:2n-6 were 49.9% and 51.1% in previously formula-fed intervention and control children, respectively, and 50.3% and 50.1% in previously breastfed intervention and control children, respectively. In conclusion, serum cholesterol ester fatty acid composition reflected differences in dietary fat quality (breast milk or formula) at the age of 7 mo, whereas dietary intervention as applied in the STRIP baby project had only a minimal effect.     

Both allergen-specific CD4 and CD8 Type 2 T cells decreased in asthmatic children with immunotherapy

Allergen-specific immunotherapy (IT) has been used for the treatment of atopic diseases since the turn of this century. The precise working mechanisms, however, remain to be clarified. The aim of this study was to investigate the role of particular subsets of allergen-specific T cells in the non-atopic individuals, untreated asthmatic children and the asthmatic children receiving immunotherapy. We collected peripheral blood from 16 untreated asthmatic children and 17 asthmatic children receiving immunotherapy over one and half years. All the patients were sensitive to mite allergen. Peripheral blood mononuclear cells (PBMC) were isolated and, in vitro , stimulated with crude mite extract to enrich the mite-specific T-cell population. After 14 days, the enriched mite-specific T cells were stimulated with phorbol-12-myristate-13-acetate (PMA) and ionomycin for intracellular detection of cytokines such as IFN-γ, IL-4 in CD4⁺ and CD8⁺ T lymphocytes. The data here demonstrated that the levels of mite-specific IgG4 and IgA increased significantly in asthmatic children after immunotherapy. In addition, both IL-4 expressing CD4⁺ and CD8⁺ T cells were significantly lower in asthmatic children after immunotherapy compared with those of before treatment and the normal control (p < 0.05). In contrast, the frequency of IFN-γ expressing CD4⁺ and CD8⁺ T cells did not significantly differ between untreated and SIT-treated groups. All these data suggested that decreased Type 2 CD4⁺ and CD8⁺ T cells might be closely correlated with the regulatory mechanisms of immunotherapy.     

Responses to immunisation with Hib conjugate vaccine in Australian breastfed and formula-fed infants

OBJECTIVE: There are conflicting reports as to whether breastfed infants respond with higher antibody levels to conjugate Haemophilus influenzae type b (Hib) vaccine compared with formula-fed infants. These observations prompted us to investigate the effect of feeding method on the antibody concentration to Hib polyribosylribitol (PRP) both prior to and 3 months after the primary course of immunisation with Hib (PRP-OMP). METHODS: We measured plasma concentrations of IgG antibody to Hib PRP by enzyme-linked immunosorbent assay in blood samples from a total of 272 breastfed and formula-fed infants prior to immunisation (7 weeks of age, n = 82 and n = 148, respectively) and again 3 months after completion of the primary course of immunisation with Hib PRP-OMP (7 months of age, n = 88 and n = 132, respectively). RESULTS: Breastfeeding was associated with lower plasma antibody titres at both times (P < 0.01, T-test) with 49% of breastfed infants having anti-PRP concentrations below 1.0 microg/mL at age 7 months. There was no reported invasive Hib disease in this cohort of infants, and nationally the effectiveness of the Hib vaccination programme remains high. CONCLUSIONS: These data suggest that breastfeeding may be associated with immunomodulation of infant Hib immunisation responses with this immunisation regime. Further research is needed to determine whether differences in antibody concentration described here are primarily determined by factors directly attributed to breastfeeding or whether other environmental factors may play a significant role.     

Neural maturation of breastfed and formula-fed infants

Background: Human milk provides infants with a full complement of all polyunsaturated fatty acids, including docosahexaenoic acid (DHA) and arachidonic acid (AA). Formula milks only contain the precursors of DHA, AA and linoleic acid, and hence formula-fed infants must synthesize their own DHA and AA. Aim: To evaluate the effect of feeding—whether breastfeeding or formula-feeding—in early infancy upon subsequent neurodevelopment and achievement of optimum brain function. Subjects and methods: The study included 53 normal, healthy infants (30 exclusively breastfed infants and 23 exclusively formula-fed infants) at the age of 1 y (±1 mo). Each infant was subjected to a full physical and neurological examination together with neurophysiological studies including flash visual evoked potential (FVEP), brainstem auditory evoked potential (BAEP) and somatosensory evoked potential (SSEP). Results: There was significant prolongation of P ₁₀₀ wave latency of FVEP in formula-fed infants, together with significant prolongation of absolute latency of waves I, III and V of BAEP in formula-fed infants compared with breastfed infants. There was significant prolongation in inter-peak latencies between cortical and Erb's components in formula-fed infants compared with breastfed infants.

Conclusion: We can conclude that VEP, BAEP and SSEP are more mature in breastfed infants relative to formula-fed infants at 1 y of age, and thus breast milk helps earlier development and maturation of some aspects of the nervous system than milk formulas.     

Immune status of infants fed soy-based formulas with or without added nucleotides for 1 year: part 2: immune cell populations

BACKGROUND: Infants fed a soy protein isolate-based formula have immunization responses similar to breast-fed infants. However, cellular aspects of the immunologic development of soy-fed infants have not been studied extensively. Nucleotides added to milk-based formula benefit infant immune status, but reports of the immunologic effects of adding nucleotides to soy-based formula are not available. This study examines immune cell populations of infants fed soy protein isolate formulas with and without added nucleotides for 1 year. METHODS: Newborn, term infants studied in a masked 12-month feeding trial were assigned randomly to soy formula groups with and without added nucleotides (n = 94, n = 92). A nonrandomized human milk/formula-fed cohort (n = 81), was concurrently enrolled. Blood samples were collected at 6, 7, and 12 months. Thirty-two immune cell populations were characterized using three-color flow cytometry. Cellular markers were chosen to assess general pediatric immune status, emphasizing maturation and activation of B, T, and NK lymphocytes. RESULTS: All cell populations, number and percentages, were within age-related normal ranges. The only significant difference found between soy formula and human milk/formula-fed infants was the percentage of CD57 + NK T cells at 12 months (human milk/formula > soy formula, P = 0.034). There were significant differences at some time points between human milk/formula-fed and nucleotide-supplemented soy formula-fed infants in populations of lymphocytes, eosinophils, total T, helper T, naive helper, memory/effector helper, CD57 - T, and CD11b + CD8 + NK cells. None of the cell populations differed between infants fed soy formula versus soy plus nucleotides. CONCLUSIONS: Infants fed this commercial soy formula demonstrated immune cell status similar to human milk/formula-fed infants, consistent with normal immune system development. The addition of nucleotides to soy formula did not significantly change specific individual immune cell populations but tended to increase numbers and percentages of T cells and decreased numbers and percentages of NK cells.     

中国九市不同喂养方式婴儿体格生长水平的横断面调查

目的 调查不同喂养方式婴儿体格生长水平的现状和差异。方法 1~<12月龄婴儿的母乳喂养、辅食添加及体格生长数据来自2015年“第五次中国九市7岁以下儿童体格发育调查”。1~<6月龄婴儿的喂养方式分为纯母乳喂养、部分母乳喂养和人工喂养,~<12月龄的喂养方式分为持续母乳喂养和人工喂养。不同喂养方式婴儿体重、身长及头围生长水平比较采用方差分析或t检验。结果 共纳入1~<12月龄婴儿59 170人。1~<6月龄纯母乳喂养率、部分母乳喂养率和人工喂养率分别为48.6%、37.4%和14.0%,~<12月龄持续母乳喂养率和人工喂养率分别为59.9%和40.1%。1~<6月龄纯母乳喂养婴儿平均体重略高于部分母乳喂养婴儿,差值范围为0.06~0.20 kg;也略高于人工喂养婴儿,差值范围为0.09~0.22 kg。6~<12月龄持续母乳喂养婴儿平均身长低于人工喂养婴儿,差值范围为-0.3~-0.1 cm。不同喂养方式在6~<12月龄体重、1~<6月龄身长及1~<12月龄头围上差异均无统计学意义。不同喂养方式婴儿体重、身长及头围生长模式与WHO儿童生长标准相似,但总体上体重和身长平均生长水平略高于WHO儿童生长标准。结论 不同喂养方式生长模式相似,在生后的前半年纯母乳喂养婴儿的生长水平略高于部分母乳喂养和人工喂养婴儿,在后半年持续母乳喂养婴儿的生长水平略低于人工喂养婴儿。     

α-Lactalbumin-enriched low-protein infant formulas: a comparison to breast milk feeding

Tryptophan (TRP) is the limiting amino acid in low-protein infant formulas. This is mainly due to lower α-lactalbumin (αLA) content in cow's milk whey as compared with human milk protein. To study the effect of αLA-enrichment on the TRP supply, cross-over studies were carried out in 20 healthy infants up to 3 months of age. In this study, two protein-reduced (1.3%) infant formulas (moderate TRP content of 1.88% and higher TRP content of 2.10%) were alternately fed over a 2 week period in two groups of infants. Serum TRP levels of the formula-fed infants with the higher TRP content did not differ significantly from an exclusively breastfed control group of 11 infants (10.5 ±4.8 versus 10.9±4.7mgl^-1, p = 0.841), whereas levels of the formula-fed infants with the moderate TRP content were significantly lower (7.4 ± 3.9, p = 0.038). The supplementation of αLA resulting in a higher TRP supply to low-protein diets is a further step towards the production of infant formulas more closely adapted to human breast milk.     

Children with recurrent otitis show defective IFNγ-producing cells in adenoids

Infectious diseases are frequently observed in children and their recurrence represents a demanding challenge for the paediatrician. It has been hypothesized that a defective immune response may occur in these patients. The aim of the present study was to evaluate whether children presenting with recurrent otitis have a defective interferon (IFN)γ production by the lymphocytes of peripheral blood and of adenoid tissue, in comparison with children without recurrent otitis. Our study group was represented by 58 children undergoing adenoidectomy for adenoidal hypertrophy. They were subdivided into two groups according to the recurrence of otitis (≥3 per year) or not (<3 per year). Intracellular cytokine profile of lymphocyte subsets in adenoids and peripheral blood was evaluated by flow cytometry analysis. Children with recurrent otitis showed a significantly lower percentage of CD8+-producing IFNγ cells in adenoids than children with <3 otitis per year (p = 0.003). The reduced capability of the adenoid cells to produce INF-γ may induce a high susceptibility to the recurrence of otitis in children.     

Feeding a formula supplemented with long chain polyunsaturated fatty acids modifies the "ex vivo" cytokine responses to food proteins in infants at low risk for allergy

Long chain polyunsaturates (LCP) status during the early neonatal period is associated with a reduced risk of atopic symptoms and later allergies. In this study, we characterized the immune response of low-risk, term, formula-fed infants randomized at 相似文献   

Peripheral blood lymphocyte subsets in children with frequent upper respiratory tract infections

It is a common and well-known fact that infants and preschool children undergo frequent episodes of upper respiratory tract infections. The majority of these children do not have a recognized immunodeficiency. The aim of the present study was to evaluate the effects of frequent upper respiratory tract infections on cellular immunity, using peripheral blood lymphocyte subsets and activation markers as defining parameters. The study group consisted of 16 children (aged 2-6 years) with frequent upper respiratory tract infections; 30 age-matched healthy children served as controls. Peripheral blood T, B, NK cells; T lymphocyte subsets; naive and memory cells; and activation markers were analyzed by using monoclonal antibodies and flow cytometry. White blood cell count (WBC) was found to be markedly increased in the study group compared to controls (p < 0.05). The absolute number of lymphocytes was also higher than that of the healthy children. The relative size of the CD3+CD8+ T lymphocytes and the relative and absolute numbers of CD3-CD16+56+ NK cells were found to be higher in patients than the controls. All the remaining percentages and numbers of the T cell subgroups including naive and memory cells and B lymphocytes did not show any difference, while CD3+CD25+ cell numbers were markedly increased (p < 0.05). In conclusion, the examination of peripheral blood lymphocyte subsets in children with frequent upper respiratory tract infections is important in evaluating cellular immune alterations due to antigenic stimulation; however, it is neither essential nor cost-effective in the management of the disease. This study has shown that both the percentage and absolute numbers of peripheral blood lymphocyte subsets maintain their normal status in children with frequent upper respiratory tract infections.     

Influence of feeding formula and breast milk fortifier on lymphocyte subsets in very low birth weight premature newborns

BACKGROUND: It is well known that breast-feeding protects the newborn from infectious diseases. This is especially important for very low birth weight preterm infants, whose immune systems are immature. In this study we investigated how a milk fortifier and replacement formula affected lymphocyte subsets in preterm infants. METHOD: The study assessed the effects of different types of feeding (human milk, n = 14; fortified human milk, n = 16; formula, n = 14) on lymphocyte subsets in 44 very low birth weight preterm infants. For each baby, two consecutive blood samples were collected 7-10 days apart during the full enteral feeding period. For each sample, the percentages of CD3+ (pan-T), CD19+ (B-cell), CD4+ (T-helper), CD8+ (T-suppressor), and CD3-CD16/56+ (natural killer cell) lymphocytes were measured in a flow cytometer, and the absolute count for each subset was calculated based on the total lymphocyte count. Within each feeding group, the absolute numbers of each lymphocyte subset in the two consecutive samples were compared. Also, the mean absolute counts for each cell type were compared among the 3 groups for the first set of blood samples, and the same comparisons were made for the second set. RESULTS: The mean number of CD3-CD16/56+ cells in the formula-fed infants was significantly lower than the corresponding means in the groups fed human milk alone and fortified human milk (p = 0.037). CONCLUSION: The findings suggest that babies fed formula have different lymphocyte subset compositions than those fed breast milk or fortified breast milk.