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K Granfors

Publications and source records attributed to K Granfors.

At least 145 records · Page 8Linked to original sources
PubMed1986

IgA-anti-yersinia antibodies in yersinia triggered reactive arthritis.

Patients who develop reactive arthritis after yersinia enteritis are characterised by high and persisting IgA-anti-yersinia antibodies. We have further analysed the humoral immune response to yersinia in this condition. Total concentrations of IgM, IgG, IgA, and secretory IgA in the serum and specific anti-yersinia antibodies belonging to IgA1, IgA2, or secretory IgA were compared in patients with or without reactive arthritis. In the former group the serum concentration of secretory IgA and of yersinia specific antibodies in all categories studied was raised compared with the level in patients without joint symptoms; the difference was most significant for the IgA-anti-yersinia antibodies with secretory piece or with J chain. The findings suggest that the strong antibody response in the patients developing reactive arthritis is due to a chronic stimulation of the intestinal lymphoid tissue.

Antibodies, Bacterial↗
PubMed1985

Pathogenesis of Yersinia-triggered reactive arthritis: immunological, microbiological and clinical aspects.

When a patient develops reactive arthritis after Yersinia enteritis, the following conditions are often fulfilled: the patient is HLA-B27-positive; however, some B27-negative individuals develop severe arthritis and some positives do not, in the initial phase, the diarrhea is milder, the anti-Yersinia antibody response of IgG class is more vigorous and persists longer, the anti-Yersinia antibody response of IgA class is more vigorous and persists much longer, the anti-Yersinia antibodies of IgA1 and IgA2 subclass, those with J-chain and, especially, those with secretory piece are produced more vigorously, indicating local immunostimulation close to the intestinal epithelium, in the early phase, Yersinia-IgM immune complexes are found in the circulation, and the lymphocyte transformation response against not only Yersinia but also against other gram-negative enteric bacteria is weaker. When all these aspects are considered together a strong suspicion arises that the patients who are destined to develop reactive arthritis fail in their first line of defense against the invading organism when contracting a Yersinia enteritis. This may lead to persistence of the microorganism within the body, e.g., in the intestinal epithelium or in the mesenteric lymphoid tissues, maintaining a stimulus for a prolonged--apparently futile and perhaps harmful--antibody production. Finally, the initiating and decisive factor should not be forgotten: the Yersinia. Why and how it triggers the process is at present one of the enigmas of the pathogenesis of reactive arthritis.

Antibodies, Bacterial↗
PubMed1985

A Yersinia enterocolitica serotype 0:3 lipopolysaccharide-specific monoclonal antibody reacts more strongly with bacteria cultured at room temperature than those cultured at 37 degrees C.

It has been suggested that the O-side chains of the lipopolysaccharide (LPS) of serotype 0:3 strains of Yersinia enterocolitica vary quantitatively and qualitatively depending on whether they are cultured at 37 degrees C or 25 degrees C. It is uncertain whether this affects the expression of the serotype-specific antigens that are probably carried on the LPS. We studied this question with a serotype 0:3-specific monoclonal antibody, 2C1. This monoclonal antibody immunoprecipitated a 39K major protein from detergent-solubilized 125I-labeled Yersinia preparation. However, results of Western blot experiments demonstrated that the antigens reactive with 2C1 were not actually the 39K protein but the O-side chains of the LPS. Significantly, reactivity could be detected whether the bacteria were cultured at room temperature or at 37 degrees C. However, absorption experiments confirmed that there were less accessible antigenic determinants on the 37 degrees C-LPS. The LPS preparations were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and silver staining. These SDS-PAGE profiles showed that less O-side chains were present in the 37 degrees C-LPS. Hence, the most likely explanation for our observation is that the 37 degrees C incubation condition induced a partial smooth to rough transition of the Yersinia LPS with a decrease in the amount of 2C1-reactive antigen.

Absorption↗
PubMed1984

Immune capacity of the chicken bursectomized at 60 hr of incubation: cytoplasmic immunoglobulins and histological findings.

Chickens were surgically bursectomized at 60 hr of incubation, before the bursal anlage appears. Completeness of the bursectomy was confirmed at autopsy at 10 weeks of age. These embryonically bursectomized (Bx)3 chickens are known to produce immunoglobulins of IgM, IgG, and IgA classes but so far no specific antibodies have been observed even after heavy immunization. The Bx chickens had mature plasma cells in an almost normal frequency when studied at 10 weeks of age. The amount of germinal center formation in the spleen and cecal tonsils was markedly decreased when compared to the control (Co) chickens. Also, the frequency of cytoplasmic IgA-positive (c-IgA+) cells was severely decreased in the Bx animals, whereas the occurrence of c-IgG+ and c-IgM+ cells was not affected to the same extent. These findings support the hypothesis that heavy-chain class switch may occur without the bursal influence, and that the bursa of Fabricius is essential only for expansion or creation of the antibody repertoire.

Aging↗
PubMed1984

Immune capacity of the chicken bursectomized at 60 hr of incubation: effect of adherent cells on the production of immunoglobulins and specific antibodies in vitro.

Cells from chickens bursectomized at 60 hr of incubation (Bx) and normal controls (Co) were assessed for the ability to secrete immunoglobulins and specific antibodies in vitro. Anti-tetanus antibodies were observed in the culture supernatants of cells from tetanus-immunized Co chickens. Cells from immunized Bx and nonimmunized Co chickens did not secrete specific antibodies. Cells of both Bx and Co chickens secreted similar amounts of immunoglobulins (IgM, IgG, IgA). Antigenic stimulation in vitro had no effect on the secretion of specific antibodies or on cell proliferation; this applies for Bx and Co chickens. To test whether antigenic stimulation in vitro together with adherent cells would induce antibody production in Bx cells, cocultures of peripheral blood adherent cells and lymphocytes from spleen or peripheral blood were used. Culture of lymphocytes with histocompatible and allogeneic adherent cells, with or without antigenic stimulation, did not enhance secretion of anti-tetanus antibodies from cells of Bx chickens. The adherent cells increased the secretion of total immunoglobulins, of all classes, by both Co and Bx cells alike. They also enhanced the secretion of specific antibodies by Co cells. These findings indicate that the functional failure of Bx lymphoid cells cannot be corrected by better antigenic presentation.

Animals↗
PubMed1984

An outbreak of Yersinia pseudotuberculosis infection.

Nineteen patients were involved in an outbreak of infection caused by Yersinia pseudotuberculosis serotype 3. No epidemics attributable to this microorganism have been previously reported; the most extensive known cluster of cases involved four children in one family and their pet dog. The key finding in the outbreak described in the present study was the bacteriologic identification of serotype 3 in stool specimens from patients with clinically typical yersiniosis. Twelve cases were identified by isolation of Y pseudotuberculosis from stool specimens. An ELISA permitted serological diagnosis of the remaining seven cases. The antibody response was unusually slow in some patients. A noteworthy feature of the outbreak was the high incidence of postinfection complications, which developed in 10 of 19 patients. In spite of active screening of the respective families and environments of the patients, no transmitting factor was found, and the precise source of the infection remains unknown.

Adolescent↗
PubMed1984

Immune capacity of the chicken bursectomized at 60 H of incubation. Effect of bursal epithelial cells and bursal epithelium-conditioned medium on the production of immunoglobulins and specific antibodies in vitro.

Cells from chickens bursectomized at 60 h of incubation (Bx) are known to produce immunoglobulins without any detectable antibody specificity. In the present work cells from Bx birds were cultured together with bursal epithelial cells (BE) or bursal epithelium-conditioned medium (BECM) to establish whether they could be induced to produce specific antibodies. Cells obtained from 10-day-old or 10-week-old birds were used. The effects were assessed with regard to the production of total immunoglobulins and specific antibodies; the birds had been preimmunized. BE had no effect on the production of immunoglobulins by either Bx or control (Co) cells. When cells from 10-week-old birds were cultured in the presence of BECM, no difference in the immunoglobulin production was seen between Bx and Co chicken cells. At the age of 10 days the cells of Bx birds produced considerably less Ig than the cells of normal Co birds. At this age BECM had no effect on the Co cells, but it markedly enhanced the production of IgA-class immunoglobulins of Bx birds. With regard to production of specific anti-tetanus antibodies, BE stimulated the production of IgA-class antibodies by cells from preimmunized Co chickens but had no effect on cells from preimmunized Bx birds. In spite of the normal production of immunoglobulins in vitro the cells of Bx chickens did not produce specific antibodies. In conclusion, these findings indicate that if B cells have matured without a contact with the bursa of Fabricius, later in vitro exposure to BE or BECM can no longer induce them to production of specific antibodies.

Aging↗
PubMed1983

Immune capacity of the chicken bursectomized at 60 hours of incubation: failure to produce immune, natural, and autoantibodies in spite of immunoglobulin production.

Chickens surgically bursectomized at 60 hr of incubation were immunized at the ages of 6, 7, 8, and 9 weeks with Escherichia coli lipopolysaccharide, levan, tetanus toxoid, and dinitrophenyl-bovine serum albumin. All antigens were given on each occasion. All embryonically bursectomized (BX) chickens had detectable concentrations of serum IgM, IgG, and IgA. On the whole, the IgG level was markedly decreased and the levels of IgM and IgA were normal. Concentrations of serum immunoglobulins did not change during immunization in the BX chickens. In spite of the production of serum immunoglobulins the BX chickens were unable to respond to the immunization by production of specific antibodies, whereas the control (CO) chickens produced good antibody response to each antigen used. The BX chickens also lacked both natural antibodies to phosphorylcholine, fecal bacteria, rabbit red blood cells (RRBC), and MHC antigens and autoantibodies to the liver, kidney, and thyroidea. Neither were any antibodies to the bursal structures observed. These results support the hypothesis that the bursal influence is not necessary for isotype switch, but is essential for the production of specific antibodies.

Animals↗
PubMed1983

Clinical correlates of circulating immune complexes in patients with recent yersiniosis.

Circulating immune complexes (CICs) and rheumatoid factor were studied in 31 patients with serologically confirmed yersiniosis (12 in a pilot series and 19 in a prospective series). Yersiniosis is an intestinal infection complicated occasionally by extraintestinal symptoms such as aseptic arthritis. Four tests representing three main principles (affinity of human platelets and of C1q for complexed IgG and of conglutinin for C3) were used for the detection of CICs, which were found in all patients. Fifty-five of 62 specimens of serum from the prospective series of 19 patients reacted positively in at least one test. The conglutinin-binding assay and the platelet-125I-labeled staphylococcal protein A test gave positive results most frequently (74% and 84% of the time). Mean levels of CICs were significantly higher in patients with prolonged gastroenteritis than in those with histocompatibility leukocyte antigen B27-positive arthritis. During follow-up, the mean level of CICs (as measured by the platelet-protein A test) decreased significantly in patients with arthritis, while CICs and rheumatoid factor persisted in patients with prolonged gastroenteritis.

Adult↗
PubMed1983

Plasmid associated antibody production against Yersinia enterocolitica in man.

The presence of plasmids was studied in 46 Yersinia enterocolitica strains isolated from human fecal specimens. In the 36 cases where specific antibodies were detected, 33 of the isolated bacteria were harbouring a 45-48 Mdalton plasmid responsible for autoagglutination and Ca2+ dependent growth at 37 degrees C. Symptoms compatible with yersiniosis were present in all patients where information was available. In the 10 cases with clinical symptoms but without specific antibodies only 2 of the isolated yersinia strains contained plasmids which were of another size. These results indicate an association between the presence of the 45-48 Mdalton plasmid in Y. enterocolitica strains and the pathogenicity of the strains to human hosts.

Agglutination↗
PubMed1983

Immune capacity of the chicken bursectomized at 60 hr of incubation: surface immunoglobulin and B-L (La-like) antigen-bearing cells.

Chickens were surgically bursectomized at 60 hr of incubation before the bursal anlage appears. Completeness of the bursectomy was confirmed at autopsy at 10 wk of age. These embryonically bursectomized (Bx) chickens are known to produce immunoglobulins of IgM, IgG, and IgA classes, but so far no specific antibodies have been observed even after heavy immunization. Regarding the appearance of surface immunoglobulin positive (s-Ig+) cells, the most striking effect of bursectomy was observed in the frequency of s-IgG+ cells, which were markedly decreased in the spleen, peripheral blood, and thymus of the Bx birds when compared with the age-matched controls. s-IgM+ cells were significantly decreased in the peripheral blood and s-IgA+ cells in the spleen of the Bx birds. In contrast to these findings, s-Ig+ cells of all three classes were present in normal frequency in the bone marrow. Bursectomy had no effect on the total lymphocyte and other white cell counts in the peripheral blood. Likewise, no effect on the frequency of B-L (Ia-like) antigen-positive cells in different organs was observed.

Animals↗
PubMed1983

Immune capacity of the chicken bursectomized at 60 hours of incubation: mitogen-induced cell proliferation and immunoglobulin secretion.

Chickens were bursectomized surgically at 60 hr of incubation. Bone marrow cells from the bursectomized (Bx) and control (Co) chickens responded equally well by proliferation to B cell mitogens (dextran sulfate, anti-mu, anti-gamma) when studied at the age of 10 weeks. In contrast, spleen cells of Bx chickens responded significantly less to anti-mu and anti-gamma than did spleen cells of the Co chickens. When observed at the age of 10 days, a significantly depressed secretion of IgM, IgG, and IgA by the Bx cells was observed in vitro. This difference between the Bx and Co chickens had disappeared when studied at the age of 10 weeks.

Aging↗
PubMed1982

Studies on the chicken lymphocyte receptor for aggregated IgG.

Chicken lymphocytes isolated from different lymphoid organs were analyzed for Fc IgG receptor by binding of heat aggregated IgG (agg IgG) in the indirect immunofluorescence test. The binding of agg IgG was shown to be specific for Fc IgG receptor, since IgM and F(ab')2 fractions were bound to the lymphocytes in a much less degree. The highest frequency of agg IgG binding cells, almost 100%, was found in the bursa of Fabricius. In contrast to bursa, only a small percentage of thymus cells bound agg IgG. Dose-dependent experiments showed that binding of agg IgG to thymus cells takes place only at high concentrations of the aggregates whereas bursa cells bind agg IgG also at low concentrations. The finding indicates the existence of high and low avidity agg IgG receptors and/or different density of Fc receptors on bursa and thymus cells. A far lower percentage of EA rosette forming cells than of agg IgG binding cells in the various lymphoid organs may depend on the existence of two different Fc IgG receptors on the chicken lymphocytes.

Animals↗