Search PubMed⌕ Search

Biomedical subjects

S Ahlstedt

Publications and source records attributed to S Ahlstedt.

At least 91 records · Page 5Linked to original sources
PubMed1987

The localization of the antibody response in milk or bile depends on the nature of the antigen.

Immunization in the Peyer's patches of rats with horse spleen ferritin or Escherichia coli 06 carrying type 1 pili resulted in an IgA antibody response detected in milk and bile and an IgG and IgM antibody response in serum, milk, and bile. The IgA antibody response to type 1 pili was as a mean 5.0-fold higher in milk than in bile. In contrast IgA antibody activity to 06 LPS was as a mean 6.3-fold higher in bile than in milk. The IgA antibodies to ferritin were randomly distributed between milk and bile. The IgG and IgM antibody activity to all three antigens studied were higher in the milk than in the bile. The secretory antibody response could be transferred from immunized rats to unimmunized rats with mesenteric lymph node cells (MLN) taken from donor rats 4 days after immunization in the Peyer's patches. IgA antibodies to pili and ferritin appeared solely in the milk of the recipients, whereas IgA antibodies to the 06 LPS only appeared in the bile. The ratios serum:milk and serum:bile for the IgG and IgM antibodies indicated an antigen-specific direction of homing with local production of these two isotypes primarily in the mammary gland. Antibody-forming cells of the IgA class could not be detected in the MLN on the day the cells were transferred. It is concluded that the difference seen in antibody distribution between milk and bile is not due to dissemination of antigen, but instead a result of different homing or expansion at the mucosal-glandular site dependent on the antigen specificity of the migrating cells.

Animals↗
PubMed1987

Differences in the kinetics of histamine formation and granulation of human basophilic cells from bone marrow, peripheral blood, and cord blood.

Human bone marrow, cord blood, and peripheral blood contain progenitor cells, which during culture mature to histamine-containing basophilic cells. In bone marrow the histamine content per Alcian blue staining basophilic cell was low before culture. Cultivation of BML cells resulted in increased histamine levels in cultures (P less than 0.05), whereas the basophilic cells did not increase significantly. Cell cultures were stimulated with conditioned medium (CM) produced with allergen-stimulated cells from atopics and from the Mo T leukaemic cell line. Cells from cultures stimulated with CM contained less histamine calculated per basophilic cell than did those from unstimulated cultures (P less than 0.05). There was a significant correlation between the numbers of basophilic cells and the histamine content in cells on day 0 prior to cultivation and after 14 days of cultivation (P less than 0.01 and P less than 0.05 respectively). In cord blood there was a correlation between the numbers of basophilic cells and the histamine levels prior to cultivation (P less than 0.05). During cultivation the number of basophilic cells increased five-fold (P less than 0.02), whereas the histamine levels did not increase resulting in a decreased histamine level per basophilic cell (P less than 0.02). In peripheral blood the basophilic cells contained the highest levels of histamine. The numbers of basophilic cells and their content of histamine showed good correlation both before and after unstimulated and stimulated cultivation (P less than 0.01), whereas unstimulated cultures did not show such correlation. The results indicate the presence of different proportions of progenitor cells in bone marrow, cord blood, and peripheral blood, all with different ability to produce histamine and become granulated basophilic cells.

Allergens↗
PubMed1987

Antibodies to penicillin in children receiving long-term secondary prophylaxis for rheumatic fever.

The occurrence of IgE and IgG antibodies to penicillin G and V in children on long-term treatment with penicillin as secondary prophylaxis for rheumatic fever was studied using Phadebas RAST (Pharmacia Diagnostics, Uppsala, Sweden) and ELISA respectively. The duration of the prophylaxis ranged between 1.5 months and 5 years (mean 1.8 years). Of 18 patients who had been given penicillin for more than 1.5 months, two had IgE antibodies and 12 had IgG antibodies to penicillin. Patients with acute rheumatic fever who had not yet received long-term treatment with penicillin had antibodies of the IgG class in two out of 12 cases. The patients gave no history of adverse reactions to the penicillin injections and there were no signs of immune complex-mediated disease. The two children who had IgE antibodies were switched to oral erythromycin instead of the penicillin injections. Penicillin is the drug of choice in the prophylaxis of rheumatic fever and can apparently be safely given as intramuscular injections of depot-penicillin to prevent recurrences of the disease and ensuing cardiac damage.

Child↗
PubMed1987

The influence of substance P on the proliferation of peripheral blood lymphocytes from normal individuals and birch pollen-allergic patients.

We have studied the influence of substance P (SP) on the proliferative response of concanavalin A (ConA)-activated peripheral blood lymphocytes from 16 birch pollen-allergic patients, sampled before and during the pollen season, and from 15 normal individuals. The median response to ConA 3 micrograms/ml in the presence of SP 10(-11)-10(-6) M, was in most instances within +/- 10% of the control value for cells from both healthy and atopic individuals. However, the individual differences were considerable. Analysis of the proliferative responses to ConA of the cells from the allergic patients sampled before and during season, revealed higher responses in the presence of 10(-6) than of 10(-7) M SP. This was in contrast to the findings in the normal individuals: only half of their cells showed such increased responses. This difference in response frequency was statistically significant between allergic patients before season and normal individuals (P less than 0.05) and between allergic patients during season and normal individuals (P less than 0.01). The difference in proliferation rate in the SP concentration interval, 10(-6) to 10(-7) M, for the cells from allergic patients, sampled both before and during season, was significantly different from the cells from healthy individuals (P less than 0.03 and P less than 0.001 respectively). The cells sampled from four allergic subjects during the birch pollen season showed a more profoundly decreased response to ConA in the presence of SP 10(-8) M, compared with their cells sampled before season. Such responses were never seen with cells sampled before season and with cells from normal individuals. The results suggest an involvement of SP in the immunoregulation, particularly in patients exhibiting allergic reactions to birch pollen.

Adult↗
PubMed1987

Immune regulation of goblet cell development.

In rats, goblet cells were found in the bronchiole epithelium surrounding enlarged lymphoid noduli. The goblet cell number increased with age. Old rats had goblet cells in the columnar epithelium. Immunization with aerosolized antigen increased goblet cell hyperplasia in bronchioli with a luminal diameter of 0.5-1.0 mm. In mice, goblet cell differentiation in the respiratory epithelium was caused by local delayed-type hypersensitivity reactions. Manipulations of the delayed hypersensitivity reactions with immune suppression and depletion of helper T cells eliminated the increase in goblet cell number.

Animals↗
PubMed1987

Regulation of the delayed hypersensitivity reaction in the lung reflected as mononuclear, mast cell and mucus cell appearance after T helper cell depletion and adoptive transfer.

Epicutaneous sensitization with picrylchloride (PiCl) induced a strongly delayed hypersensitivity (DH) reaction in mice. Local challenge in the airways of these mice resulted in increased numbers of mononuclear cells, mast cells and mucus cells. Depletion of T helper cells in vivo by treatment with monoclonal antibody (GK 1.5) inhibited the DH reaction. This treatment also resulted in a decrease in the number of mononuclear and mucus cells in the lung after intranasal challenge. The DH reaction was transferred to recipients with immune lymph node cells and spleen cells from mice sensitized epicutaneously with PiCl. The recipient mice also showed a slight increase in the number of mononuclear cells in the lung after intranasal challenge. These results indicate that T cells are not only involved in the DH reaction but also in the accompanying lung reaction.

Animals↗
PubMed1987

Effect of capsaicin on bronchial reactivity and inflammation in sensitized adult rats.

The involvement of tachykinins in the airway reactivity of ovalbumin (OA)-sensitized rats was studied by capsaicin (CAPS) treatment. In subcutaneously sensitized animals, the reactivity to both OA aerosol and serotonin given intravenously was decreased when CAPS was given after the sensitization period. No effects on the serum IgE and IgG antibody levels were seen in these animals. In contrast, when CAPS was given before the sensitization period, no effects were seen on the OA aerosol and serotonin reactivities. Immunohistochemical examination revealed that the Ia antigen expression in the bronchial epithelium was increased by both subcutaneous and aerosol sensitization. The CAPS treatment decreased this Ia antigen expression. Histological examination of mononuclear cells, mast cells and goblet cells revealed only small effects on the cell numbers by both the OA sensitization and the CAPS treatment. The results demonstrate a link between tachykinins, serotonin, the immune system and clinical lung reactivity. The mechanisms for this seem to be complex, since the timing of the CAPS treatment and antigen sensitization is crucial for the outcome.

Animals↗
PubMed1987

Lack of IgA antibody response in secretions of rat dams during long-term ovalbumin feeding. Induction of systemic tolerance in pups but not in adult rats.

Antigen uptake, serum and secretory immune response was studied in rat dams fed pellets substituted with ovalbumin during three consecutive pregnancies and lactation periods. The concentration of ovalbumin was somewhat higher in milk than in serum, and both serum and milk concentrations showed a parallel decrease with feeding time. IgA antibodies did not develop in the milk during the 7-month feeding period and no antibody response could be detected in saliva or bile. By the time of the first lactation about half of the dams had developed low titres of IgG antibodies in serum and milk and the number of IgG responders, as well as the mean antibody titre, increased with each lactation. Also when injected directly into the Peyer's patches ovalbumin induced solely IgG antibodies in the milk, while immunization with ferritin in addition resulted in both IgA and IgM antibodies in the milk against ferritin. The presence or absence of immunological tolerance to ovalbumin was examined in three groups of rats: (1) dams which had been fed ovalbumin-substituted pellets for one pregnancy and the first 14 days of the lactation period, i.e. for approximately 5 weeks altogether; (2) pups that were born by and kept together with these mothers, and (3) pups that were born by and kept together with mothers that were fed ovalbumin-substituted pellets during the pregnancy and until weaning at day 21 (altogether for 6 weeks). The rat dams in group 1 were not tolerant to a subcutaneous injection of ovalbumin 4 weeks after the termination of feeding with ovalbumin-substituted food.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Age-dependent bone marrow mast cell maturation in specific pathogen-free rats.

In the present study we have investigated an age-dependent mast cell increase. The mast cell numbers in bone marrow from (BN x Wi/Fu)F1 rats were determined using Alcian blue staining of cells in solution. From the 6th to the 19th week of age the number of mast cells in the bone marrow increased 6-fold with a marked peak around the 12th week of age. This increase in mast cell numbers was accompanied with increased histamine levels. Immunization increased the numbers further, also when the age-dependent mast cell increase was corrected for. The results should be considered in relation to previous studies revealing increased mast cell numbers in the bone marrow after immunization and also increasing numbers in the lungs of rats immunized with protein antigens or exposed to environmental antigens.

Aging↗
PubMed1986

Serum antibodies against native, processed and digested cow's milk proteins in children with cow's milk protein intolerance.

Children with or without cow's milk protein intolerance were investigated for serum antibodies to native cow's milk proteins, processed cow's milk proteins and native- and pepsin-digested beta-lactoglobulin. Antibodies of IgG and IgA isotypes were determined with ELISA and those of IgE isotype with RAST. Children who exhibited slowly appearing untoward reactions to cow's milk feeding had significantly higher titres of IgG antibodies against both native and digested beta-lactoglobulin than children with an immediate type of reaction or no intolerance. The IgG antibodies to pepsin-digested beta-lactoglobulin were efficiently inhibited by native beta-lactoglobulin even at low concentrations, which suggests that there were no antibodies specific for the degraded proteins. The children with slow reactions to cow's milk also tended to have higher antibody levels of the IgG and IgA isotypes to both native and processed cow's milk. Antibodies to this mix of antigens discriminated less well, however, than the antibodies to isolated beta-lactoglobulin between the groups of children with slowly appearing reactions, with immediate reactions and the controls. Seven out of nine children with an immediate type of reaction to cow's milk protein had IgE antibodies against cow's milk protein determined with the RAST, while this type of antibodies could not be demonstrated in any child in the two other groups. Using processed or digested protein as antigen did not increase the sensitivity of the antibody determinations.

Animals↗
PubMed1986

Origin and kinetics of IgA, IgG and IgM milk antibodies in primary and secondary responses of rats.

IgA and IgM antibodies were detected in rat milk after immunization with ferritin in Peyer's patches (Pp) 1 day after parturition but not after intramammary gland or intravenous immunization. The antibody levels decreased from day 9 to day 17 of the nursing period and were undetectable during a second lactation period. Despite the absence of milk IgM antibodies after intramammary gland or intravenous immunization, the serum levels of the IgM antibodies were similar after all three immunization methods. IgA antibodies were not found in serum after any of the immunization methods.IgG antibodies appeared in serum and milk after P. intramammary gland, and intravenous immunization. Milk and serum IgG antibodies from all the Pp-immunized animals decreased from day 9 to day 17 of the lactation period. After intramammary gland immunization, however, the IgG antibody levels increased in all the milk samples, but only in four of seven sera. The milk and serum IgG antibody levels were lower but still detectable during a second lactation period. Re-injection of ferritin in the Pp during a third lactation period resulted in higher levels of milk IgA, IgG and IgM antibodies than after the first injection. Rats with serum IgG antibodies against Escherichia coli 08 naturally present in their gut flora had no corresponding milk antibodies of any isotype. The results suggest tht milk antibodies of all three isotypes stem from local production in the mammary gland and that blood IgG and IgM antibodies originate at least partly from stimulation in Pp.

Animals↗
PubMed1986

Hepatic production of biliary IgM in the rat.

Drainage of the thoracic duct resulted in a decrease in the IgA level in rat bile, but at the same time there was an increase in both the total IgM level and the specific IgM antibody activity to Escherichia coli 06 in the bile of animals immunized in the Peyer's patches with these bacteria. The increase in total IgM was significantly higher in animals immunized with the E. coli 06 than in unimmunized rats. The level of total IgG was not altered during the drainage. IgM antibodies to E. coli 04 given intravenously during lymph drainage did not appear in the bile, whereas specific IgM antibodies to E. coli 06 occurring after active immunization increased in the bile of the same animal. The data elucidate two aspects of the hepatic IgM turnover. First IgM could take the place of IgA in cases of IgA deficiency, and second the IgM might originate from intrahepatic production.

Animals↗
PubMed1986

Antigen-specific down-regulation of bronchial reactivity in rats sensitized daily without adjuvant.

Daily sensitization with ovalbumin (OA) and dog serum albumin (DSA) without adjuvant was performed in rats for 2-week periods. When the antigen was administered subcutaneously (s.c.), antibody responses were induced, as assessed in serum and bronchial lavage, and strong increases in transpulmonary pressure (TPP) after intravenous (i.v.) challenge with antigen. Sensitization without adjuvant with antigen as aerosol for similar periods also evoked pronounced antibody formation, although only weak increases of TPP were seen after challenge. Animals sensitized s.c. with OA and simultaneously exposed to OA as aerosol exhibited suppression of the TPP increase after challenge, whereas the antibody responses were not affected to any great extent. In contrast, the increase of TPP after challenge in animals similarly sensitized s.c. with DSA were not suppressed by OA given simultaneously as aerosol or vice versa.

Adjuvants, Immunologic↗
PubMed1986

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.

Adolescent↗
PubMed1986

Clinical and immunological effects of oral immunotherapy with a standardized birch pollen extract.

Oral immunotherapy (IT) was evaluated in a pilot study in two centres in children aged 8-15 years with allergic rhinoconjunctivitis. High doses (up to 20 X 10(6) BU monthly) of a defined freeze-dried birch pollen extract administered in enteric-coated gelatine capsules were given either daily for seven consecutive days every month or once weekly. Symptom scores, as assessed by sneezing, dripping and blockage of the nose, and redness, itching and swelling of the eyes, were significantly lower in treated patients compared to untreated, or placebo treated controls after 3 to 5 months of therapy. In all the 16 treated, but only in three of eight untreated patients, the scores were lower during the pollen season 1982 than during the pollen season preceding the treatment period, despite comparable pollen counts during the two seasons. One year after beginning treatment the reactivity in conjunctival provocation tests was decreased about 10-fold (P less than 0.001) in the patients receiving more than 2 X 10(5) BU monthly compared to about two-fold in patients receiving lower doses, or placebo. Increased levels of IgE antibodies directed against birch pollen were recorded in the serum and saliva of most patients after 3-4 months of active IT. In contrast, IgG antibody responses were poor in most of the patients. Side effects, particularly from the gastrointestinal tract, appeared in all treated children. In one of them a systemic reaction occurred during IT. The study indicates that properly performed oral IT with a potent birch allergen extract in enteric-coated capsules may be effective.

Administration, Oral↗
PubMed1986

In vitro appearance of large human histamine-containing basophilic cells.

The appearance of large human basophilic cells containing histamine was followed to reflect cell maturation in cultures of peripheral blood leukocytes. Aliquots were taken on day 0 and after 7, 9-10 and 14 days in culture, and the basophilic cell numbers were determined in 200 microliter cytospin specimens stained with Wright's stain. The number of small basophils initially present declined during the culture period. The number of spontaneously appearing large basophilic cells varied among the cultures from different individuals and was slightly, though not significantly, higher in atopic individuals than in normals. In cultures of cells from atopic individuals, the number of large basophilic cells was reproducibly increased by the addition of appropriate allergen to the cultures. In cultures of cells from normal individuals, the number was increased two- to six-fold by adding conditioned medium (CM), either from 3-day cultures of cells from atopic individuals stimulated with allergen or with CM from the Mo T cell leukemic line. The addition of mitomycin C decreased the number of large basophilic cells and cycloheximide abrogated their appearance.

Allergens↗