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E Isolauri

Publications and source records attributed to E Isolauri.

At least 127 records · Page 7Linked to original sources
PubMed1994

Evidence for eosinophil activation in cow's milk allergy.

To assist in identifying pathogenetic mechanisms in different clinical manifestations of cow's milk allergy (CMA), the involvement of eosinophil cells in immunoinflammatory reactions was evaluated. The study population comprised 28 patients, aged from 5.8 to 43.0 months, who had challenge-proven CMA, manifested either cutaneously (n = 17) or gastrointestinally (n = 11). A clinical cow's milk challenge was performed in hospital after a 4 week cow's milk elimination period. Eosinophil activation in vivo was studied by measuring the serum level of eosinophil cationic protein (ECP) before the oral cow's milk challenge, mean (SD) 27 (12) hours after commencing the challenge and one week later. These results were compared to those of 80 non-allergic age-matched controls. During the challenge, the level of ECP increased from 6.2 (4.5, 8.0) micrograms/L to 20.0 (9.5, 30, 4) micrograms/L in CMA patients with skin manifestations but not in those with gastrointestinal symptoms. The increase was shown to be transient. We conclude that eosinophil degranulation is an important immunologic mechanism leading to allergic inflammation in cutaneously manifested CMA.

Blood Proteins↗
PubMed1994

A prospective study of humoral immune responses to cow milk antigens in the first year of life.

Previous studies have shown that in cow milk allergy the specific immune response to dietary cow milk antigens is deficient. This study aimed at delineating the development of humoral immune response to cow milk antigens in healthy infants. Twenty-five healthy newborns were enrolled, and seen at scheduled visits at the ages of three, six and eleven months, and they formed two groups: those breastfed and those fed adapted cow milk formulae. The local immune response in the gut was approximated using the ELISPOT assay of circulating antibody secreting cells. At the age of three months, in the formula fed group, cells secreting specific IgA to cow milk antigens were detected despite low levels of IgA serum antibodies. The total number of IgA secreting cells increased with age (p = 0.001). The milk in the infant diet directly influenced this development so that the age related increase was significantly greater in the formula fed group (p = 0.04). The results indicate that diet has a significant effect on the developing immune system, and that healthy infants are able to respond in an antigen specific fashion to dietary antigens, which may be central in attaining clinical tolerance of such antigens.

Animals↗
PubMed1994

New concepts of allergy to cow's milk.

CMA is a diagnostic and therapeutic problem in the field of pediatrics. The response to oral cow's milk challenge was evaluated in patients with suspective CMA. To investigate immune mechanisms in different subtypes of CMA, suppressor activity, in vitro IFN-gamma and IL-4 generation, eosinophil activation and humoral immune response were measured. Also, changes in the function of the immune system were evaluated when patients had clinically recovered from CMA. The results of different measurements were correlated with the patients' clinical response to cow's milk challenge. The prechallenge suppressor activity was found to be low in patients with challenge-proven CMA when compared with those clinically negative to oral cow's milk challenge but had normalized after a 4-18 month milk-elimination period in patients who had recovered from CMA. IFN-gamma generation was low in patients with active CMA but had clearly enhanced in patients recovering from CMA. The serum concentration of ECP increased significantly during oral cow's milk challenge in patients with cutaneously manifested CMA. Measured by the ELISPOT method, the patients with active CMA mounted a high, non-antigen-specific immune response but were unable to direct the antigen-specific response, especially in the IgA class. After a follow-up of a mean 13.5 months on cow's milk elimination diet, the immune response to cow's milk antigens had developed in patients who had recovered from CMA. The development in the capacity to mount an adequate immune response to specific protein antigens, especially in the IgA class, can be interpreted as deriving from the development in T-lymphocyte regulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Lactobacillus casei strain GG reverses increased intestinal permeability induced by cow milk in suckling rats.

BACKGROUND: Lactobacilli constitute a major part of the microflora throughout the gastrointestinal tract. This study aimed to investigate the effect of lactobacilli on the gut mucosal barrier. METHODS: Rat pups were divided into three experimental feeding groups at the age of 14 days. In addition to normal maternal milk, group "milk" received a daily gavage of cow milk, group "milk-GG" received Lactobacillus casei strain GG with cow milk, and controls were gavaged with the same volume of water. At 21 days, the absorption of horseradish peroxidase across patch-free jejunal segments and segments containing Peyer's patches was studied in Ussing chambers. RESULTS: The mean absorption of intact horseradish peroxidase expressed in ng.h-1.cm-2, was significantly different in the study groups in both patch-free segments (controls, 9 [95% confidence interval, 7-12]; milk, 72 [60-87]; and milk-GG, 15 [4-52]) and in segments containing Peyer's patches (controls, 3 [1-17]; milk, 80 [43-151]; and milk-GG, 15 [4-56]). There was a significant increase in the frequency of cells secreting antibodies to beta-lactoglobulin (enzyme-linked immunospot assay) in the milk-GG group. CONCLUSIONS: Prolonged cow milk challenge in suckling rats increases gut permeability to intact proteins, whereas Lactobacillus GG counteracts this permeability disorder. The results suggest a link between the intensity of the antigen-specific immune response and stabilization of the mucosal barrier.

Animals↗
PubMed1993

Increased in vitro intestinal permeability in suckling rats exposed to cow milk during lactation.

Specific mucosal barrier functions of the gut develop in the newborn to combat the constant challenge of foreign antigens. To determine whether exposure to cow milk antigens interferes with this maturational process, jejunal permeability to macromolecules and the activation of immune mechanisms were studied in preweaning rats. At the age of 14 days, rat pups were divided into three feeding groups. Controls (n = 18) remained on normal maternal milk; group CM (n = 27) additionally received a daily gavage feed of cow milk; and in group D (n = 23), cow milk was given to dams. At 21 days, when "gut closure" normally occurs, intestinal in vitro absorption of horseradish peroxidase in its intact form was significantly higher in group CM and in group D than in controls (F = 5.6; p = 0.006): group CM: mean, 37.8 ng/h/cm2; 95% confidence interval (CI), 19.4-73.6; group D: mean, 26.9 ng/h/cm2; 95% CI, 8.2-88.2; controls: mean, 4.0 ng/h/cm2; 95% CI, 1.2-13.9. In association with increased jejunal permeability, there was enhanced jejunal eosinophilic infiltration in group CM. In group D, the number of specific antibody-secreting cells in peripheral blood against beta-lactoglobulin was significantly higher than in group CM and controls. These data indicate that there is a critical period in development when feeding cow milk antigens delays gut closure. They further suggest that mucosal barrier function is impaired due to a local hypersensitivity reaction to cow milk antigens, irrespective of the protection of maternal milk or maternal antigen processing.

Age Factors↗
PubMed1993

Immunologic disturbances in cow's milk allergy, 1: Delayed maturation of suppressor activity.

To assist in identifying pathogenetic mechanisms in different subtypes of cow's milk allergy (CMA), the function of immunoregulatory T-lymphocytes was studied. The study population consisted of 23 patients, mean [95% confidence interval] age of 25.6 [19.5, 33.6] months, who had challenge-proven cow's milk allergy manifested with either skin (n = 9) or gastrointestinal (n = 14) symptoms; in addition, 13 age-matched disease controls were studied. Patients with challenge-proven CMA were rechallenged to establish whether they had acquired clinical tolerance to cow's milk. The suppressor activity of isolated lymphocytes was measured in vitro by a cell coculture at rechallenge and in 10/23 patients at diagnosis. At diagnosis, patients with CMA (n = 10) showed a decreased mean [95% CI] suppressor activity, induced by either Concanavalin A, 7[-2,15]%, or cow's milk, 3[-8,14]% as compared with disease controls (n = 13), 19[15,24]% and 24[17,31]%; F = 7.1, p = 0.004 and F = 6.7, p = 0.005, respectively. At rechallenge the suppressor activity, induced both by Concanavalin A and cow's milk, reached the level of disease controls only in patients who had acquired clinical tolerance to cow's milk (n = 13/23), but not in those retaining CMA (n = 10/23). Our results indicate that the maturation of suppressor function is delayed in CMA, which might be of primary importance in the etiopathogenesis of CMA.

Child, Preschool↗
PubMed1993

Immunologic disturbances in cow's milk allergy, 2: Evidence for defective interferon-gamma generation.

We have investigated the role of interferon-gamma (IFN-gamma) in the regulation of antigen-specific T-cell function in patients with cow's milk allergy. The study population consisted of 22 patients, aged from 7.6 to 56.9 months, who had challenge-proven cow's milk allergy (CMA) manifested with either skin (n = 9) or gastrointestinal (n = 13) symptoms. In addition, 11 age-matched children and 6 adults, mean (SD) age 31 (7) years, were studied as controls. Patients with challenge-proven CMA were rechallenged to establish whether they had acquired clinical tolerance to cow's milk. The spontaneous and mitogen-induced IFN-gamma and interleukin-4 (IL-4) generation of isolated lymphocytes was evaluated in vitro with commercial ELISA Kits at diagnosis and at reassessment. At diagnosis, the IFN-gamma production was not detectable in patients with CMA as compared with control children. IL-4 production was almost undetectable in all subjects in this study. However, at reassessment the CMA patients who had acquired clinical tolerance to cow's milk (n = 16) showed enhanced IFN-gamma production, when compared with that of control children, but still lower when compared with that of healthy adults. Our results indicate that the maturation of IFN-gamma producing T-cells is delayed in CMA, which could lead to a disturbance in the regulation of T-cell function. This defect might be an important etiologic factor for CMA.

Child, Preschool↗
PubMed1993

Diet during rotavirus enteritis affects jejunal permeability to macromolecules in suckling rats.

We studied the influence of diet during diarrhea on gut mucosal barrier in a suckling rat model. Rat pups were inoculated with IDIR virus (a group B rotavirus) at 10 d of age. Beginning 2 d postinfection, in addition to maternal milk, group CM received a daily gavage of cow milk and group GG received Lactobacillus casei strain GG, a human strain previously shown to survive the passage through the gastrointestinal tract and temporarily colonize the gut. Group CMGG received a combination of these, and control animals were gavaged with tap water. At 21 d of age, jejunal absorption of intact and degraded horseradish peroxidase (HRP) in Ussing chamber was markedly higher in IDIR virus-infected than in noninfected controls. In the two groups gavaged with cow milk, group CM and group CMGG, the numbers of specific antibody-secreting cells (enumerated by the solid-phase enzyme-linked immunospot assay) against beta-lactoglobulin were significantly higher than in the groups that had not received cow milk. In parallel with immune system activation, a statistically significant increase in the absorption of intact HRP (mean and 95% confidence interval, ng x h-1 x cm-2) was detected: group CM, 302 (155, 586); group CMGG, 174 (56, 545); infected controls, 121 (57, 257); and group GG, 44 (8, 254). A decrease in the uptake of intact HRP (F = 3.64, p = 0.06) and degraded HRP (F = 9.50, p = 0.004) was associated with the introduction of L. casei GG to the diet, irrespective of coexposure to cow milk.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Local immune response in patients with cow milk allergy: follow-up of patients retaining allergy or becoming tolerant.

To assist in identifying factors that determine the clinical outcome of cow milk allergy, we subjected to rechallenge 37 patients with a history of cow milk allergy, mean (+/- SD) age 27.6 +/- 7.1 months, after a follow-up of 13.5 +/- 5.1 months with a milk-free diet. A solid-phase enzyme-linked immunoassay was used to assess the total number of immunoglobulin-secreting and specific antibody-secreting cells among peripheral blood lymphocytes primed during provocation by milk antigens, giving indirect evidence of local immune response in the gut. Patients with persistent cow milk allergy (n = 13) had milder reactions at rechallenge than they had shown at the time of diagnosis. Numbers of immunoglobulin-secreting cells in these patients increased significantly from a geometric mean (95% confidence interval) in the IgA class of 1570 (1009, 2445) to 2984 (1941, 4583) IgA-secreting cells/10(6) cells, in the IgG class of 1445 (1067, 1959) to 2740 (1698, 4425) IgG-secreting cells/10(6) cells, and in the IgM class of 842 (534, 1325) to 2235 (1429, 3495) IgM-secreting cells/10(6) cells. By contrast, in patients (n = 24) who had acquired cow milk tolerance, the number of immunoglobulin-secreting cells did not increase during provocation. The total number of IgA-secreting cells before rechallenge was significantly higher than it had been before the initial challenge. The patients who acquired cow milk tolerance also had specific antibody-secreting cells of IgA isotype before the second challenge. These results indicate that in cow milk allergy the ability to mount a local immune response against cow milk antigens, particularly in the IgA class, is related to the suppression of clinical sensitivity.

Animals↗
PubMed1992

Preponderance of IgM from blood lymphocytes in response to infantile rotavirus gastroenteritis.

Immune responses triggered by acute rotavirus infection in infants are poorly defined. To obtain indirect evidence as to gut immune response to rotavirus, the solid phase enzyme linked immunoassay (ELISPOT) of immunoglobulin and specific antibody secreting cells among circulating blood lymphocytes was used. Seventeen well nourished patients from seven to 25 months of age were studied during the peak of rotavirus infection, and in convalescence. A transient but distinct immunoglobulin secreting cell response in IgM and IgG, but not in IgA, classes was found during the diarrhoeal phase. This response included a quantitatively prominent activation of specific antibody secreting cells against rotavirus in the IgM class, mean (95% confidence interval (CI)) 82 (32, 210)/10(6) cells v 8 (4, 17)/10(6) cells in convalescence, p = 0.01. The response in the IgA class was not significant. The results indicate that local immune mechanisms are activated in rotavirus diarrhoea. They further suggest that although IgA is the predominant immunoglobulin operative in the gastrointestinal tract, this may not be the case in infantile rotavirus enteritis.

Antibody Specificity↗
PubMed1992

Cow's milk provocation induces an immune response to unrelated dietary antigens.

The activation of immune mechanisms was evaluated by the solid phase enzyme linked immunoassay of immunoglobulin and specific antibody secreting cells in 27 patients (aged from nine to 69 months), subjected to a diagnostic cow's milk challenge or a rechallenge. A significant rise in the total number of immunoglobulin secreting cells was associated with clinically positive (n = 17), but not a negative (n = 10) cow's milk challenge in all immunoglobulin isotypes. The number of specific antibody secreting cells against beta lactoglobulin, mean (95% confidence interval), increased from 4.8 (1.4, 15.8) to 16.9 (5.5, 52.7) specific antibody secreting cells/10(6) cells, p = 0.02, and against casein from 2.2 (0.8, 6.1) to 7.5 (2.5, 22.5) specific antibody secreting cells/10(6) cells, p = 0.01, in patients positive to challenge in the IgM class only, indicating defective immune elimination of milk antigens. In addition to the specific immune response to cow's milk antigens, an increase in IgM specific antibody secreting cells against an unrelated dietary antigen, gliadin, from 8.2 (2.1, 31.1) to 31.0 (14.2, 67.6) specific antibody secreting cells/10(6) cells, p = 0.01, was observed. These results indicate that cow's milk challenge, in patients who have cow's milk allergy, induces a strong non-antigen specific immune response that includes a response against unrelated antigens concomitantly present in the intestinal lumen. Activation of such immune mechanisms may hence reflect increased antigenic load caused by the immune mediated lesion in the gut mucosa.

Antibody Specificity↗
PubMed1992

Enhancement of the circulating antibody secreting cell response in human diarrhea by a human Lactobacillus strain.

Human Lactobacillus sp strain GG (Lactobacillus GG) administered during acute rotavirus diarrhea has been shown to promote clinical recovery. To elucidate the immune mechanisms behind such a favorable outcome, the ELISPOT (solid phase enzyme-linked immunospot) assay of Ig- and specific antibody-secreting cells among circulating lymphocytes was used, giving indirect evidence of the immunologic events in the gut. After rehydration, 39 children with acute rotavirus diarrhea, mean age 16 (SD 6) mo, randomly received either a Lactobacillus GG fermented milk product (study group) or a pasteurized yogurt (placebo group). The duration of diarrhea was significantly shorter in the study group than in the placebo group [mean 1.1 (SD 0.6) versus 2.5 (SD 1.4)d, p = 0.001]. Lactobacillus GG therapy was associated with a significantly enhanced nonspecific humoral response during the acute phase of the infection, reflected in the IgG, IgA, and IgM Ig-secreting cell numbers. At convalescence, 90% of the study group versus 46% of the placebo group had developed an IgA specific antibody-secreting cell response to rotavirus (p = 0.006). The results indicate that Lactobacillus GG promotes recovery from rotavirus diarrhea via augmentation of the local immune defense. Furthermore, specific IgA response to rotavirus is endorsed, which is possibly relevant in protection against reinfections.

Animals↗
PubMed1992

Early dietary antigens delay the development of gut mucosal barrier in preweaning rats.

To determine the effects of early antigen exposure on the maturation of the gastrointestinal mucosal barrier, rat pups were divided into three groups at the age of 14 d. In addition to normal maternal milk, group CM (n = 24) received daily a gavage feed of cow's milk and group PH (n = 20) a whey protein hydrolysate during the experimental feeding period (14-20 d). Controls (n = 15) remained on maternal milk only. At 21 d, when "gut closure" normally occurs, intestinal absorption of horseradish peroxidase (HRP), was examined in vitro in Ussing chambers. The absorption of intact HRP [geometric mean (95% confidence interval)] was significantly higher in group CM [35.3 (16.7, 74.7) ng.h-1.cm-2] than in group PH [5.2 (1.4, 19.5) ng.h-1.cm-2] and in controls [3.4 (0.8, 15.1) ng.h-1.cm-2; F = 5.54, p = 0.006]. The absorption of degraded HRP was comparable in all groups. There were no modifications in electrical parameters in association with increased mucosal permeability to HRP. Furthermore, in group CM electron-microscopic studies disclosed accumulation of HRP in the cytoplasm of the epithelial cells and in the intercellular spaces where cell junctions remained unaltered. These results indicate that early administration of antigens delays the process of gut closure. They further suggest that continuously enhanced endocytosis of macro-molecules is induced by an insult to the mucosa as part of the host response to these antigens, irrespective of the protection afforded by maternal milk.

Animals↗
PubMed1991

Increased beta-lactoglobulin absorption during rotavirus enteritis in infants: relationship to sugar permeability.

We studied absorption of the potentially allergenic protein beta-lactoglobulin during acute rotavirus diarrhea in infants and assessed the relationship of this macromolecular absorption with intestinal sugar permeability. After oral rehydration, 38 patients with acute gastroenteritis were given orally a 100-ml solution containing 4 g (11.7 mmol/L) of lactulose and 0.8 g (4.4 mmol/L) of mannitol, and their recovery rate as shown in urine passed during the subsequent 5 h was measured. A blood sample was taken 2 h after a milk feed for ELISA measurement of beta-lactoglobulin in circulating immune complexes. Twelve nondiarrhea patients were studied after an overnight fast as controls. Immune complexes containing beta-lactoglobulin were found in the serum of all, but the levels [median (range)] were significantly higher in patients with rotavirus diarrhea [686 (36-4352)] than in nondiarrhea patients [165 (0-2594)]; p = 0.007. The mean (95% confidence interval) lactulose/mannitol urinary recovery ratios were increased in patients with acute diarrhea [0.19 (0.10, 0.30)] compared to nondiarrhea patients [0.01 (0.005, 0.02)]; p = 0.0001. Thus, a significant correlation between beta-lactoglobulin absorption and sugar permeability was found; Spearman's rank correlation coefficient = 0.42, p = 0.004. This correlation was not, however, direct but was due to an inverse relationship between urinary recovery of mannitol and serum beta-lactoglobulin immune complexes. These results indicate that rotavirus gastroenteritis is associated with enhanced beta-lactoglobulin absorption and elevated lactulose/mannitol permeability test results, but these represent different phenomena.

Antigen-Antibody Complex↗
PubMed1991

A human Lactobacillus strain (Lactobacillus casei sp strain GG) promotes recovery from acute diarrhea in children.

To determine the effect of a human Lactobacillus strain (Lactobacillus casei sp strain GG, Gefilac) on recovery from acute diarrhea (82% rotavirus), 71 well-nourished children between 4 and 45 months of age were studied. After oral rehydration, the patients randomly received either Lactobacillus GG-fermented milk product, 125 g (10(10-11) colony-forming units) twice daily (group 1); Lactobacillus GG freeze-dried powder, one dose (10(10-11) colony-forming units) twice daily (group 2); or a placebo, a pasteurized yogurt (group 3) 125 g twice daily; each diet was given for 5 days, in addition to normal full diet otherwise free of fermented dairy products. The mean (SD) duration of diarrhea after commencing the therapy was significantly shorter in group 1 (1.4 [0.8] days) and in group 2 (1.4 [0.8] days) than in group 3 (2.4 [1.1] days); F = 8.70, P less than 0.001. After rehydration, each dietary group maintained a positive weight trend. The urinary lactulose-mannitol recovery ratios (means [95% confidence intervals]) on admission were 0.09 (0.03, 0.24) in group 1, 0.12 (0.07, 0.22) in group 2, and 0.08 (0.04, 0.18) in group 3; no significant alterations in intestinal permeability were observed at retesting after 2 days of realimentation. The result indicates that early nutritional repletion after rehydration causes no mucosal disruption and is beneficial for recovery from diarrhea. It is further suggested that Lactobacillus GG in the form of fermented milk or freeze-dried powder is effective in shortening the course of acute diarrhea.

Acute Disease↗
PubMed1990

Antigen absorption in rabbit bacterial diarrhea (RDEC-1). In vitro modifications in ileum and Peyer's patches.

Intestinal absorption of antigenic (intact) and degraded beta-lactoglobulin and horseradish peroxidase was studied in rabbits experimentally infected at weaning with the rabbit-specific Escherichia coli strain RDEC-1 (015:NM). Transepithelial fluxes of both proteins were measured at four stages after infection: early, peak, late, and recovery, on segments of ileum and Peyer's patches mounted in Ussing chambers. During this period of observation, absorption of antigenic beta-lactoglobulin and intact horseradish peroxidase decreased significantly in the ileum and Peyer's patches of age-matched controls. No significant age-related decrease was observed in the controls for the transport of these proteins in degraded form. RDEC-1 infection caused, first, a rise in degraded protein fluxes across Peyer's patches only, during the early phase of the disease. Second, during the peak phase of infection, absorption of antigenic beta-lactoglobulin by the ileum rose to 74.0 ng/hr/cm2 (90% confidence interval: 63.1, 86.8) vs 15.8 (5.8, 42.8) in the controls (P = 0.07), and absorption of intact horseradish peroxidase rose to 21.8 (16.5, 26.7) ng/hr/cm2 vs 4.4 (0.7, 26.6) in control ileum, (P = 0.09). These rises, which were similar in Peyer's patches, delayed the physiologic decrease in protein absorption that occurs with age. These results indicate that increased antigen absorption is observed during bacterial diarrhea and that it might interfere with the immune responses of the host.

Animals↗
PubMed1990

Development of the neonatal rat small intestinal barrier to nonspecific macromolecular absorption: effect of early weaning to artificial diets.

We studied the effect of early weaning from maternal breast milk to artificial diets on rat jejunal absorption of an exogenous 40-kD glycoprotein, horseradish peroxidase (HRP). Rat pups, fed maternal milk (MM) from birth, received one of three diets for the last 4 d before weaning (d 17-21): MM, protein hydrolysate formula (PH), or soy formula (S). Some rats were pretreated on d 14 with intraperitoneal hydrocortisone (5 mg/rat). In MM-fed rat pups, jejunal HRP absorption was markedly higher on d 17 than on d 21. [Geometric means (95% confidence interval) were: d 17, 626.4 (461.3, 850.6) versus d 21, 90.6 (48.2, 170.5) IU HRP/mL x cm x min, p less than 0.01.] By contrast, 21-d-old PH- and S-fed pups maintained elevated absorption of the tracer [PH, 292.3 (177.5, 480.6), p less than 0.05 versus MM pups, S, 340.8 (164.4, 704.8), p less than 0.01 versus MM pups]. Wt-matched control studies indicate that the difference in HRP absorption was not due to the smaller body wt of formula-fed pups. The increased absorption in formula-fed animals was suppressed by hydrocortisone. In S-fed pups, the increased macromolecular absorption appeared, in part, to be the result of diffusion across altered villus absorptive cells. In PH-fed pups, there was no evidence of damage and HRP absorption appeared to occur by vesicle-mediated transport. Delay in the normal maturation of small intestinal "closure" appears to be associated with early weaning to artificial diets. This may lead to increased nonspecific macromolecular permeability that could result in immune-mediated sensitization and food intolerance.

Age Factors↗