PubMed Health⌕ Search

Biomedical subjects

A Toivanen

Publications and source records attributed to A Toivanen.

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

Yersinia-associated arthritis in the rat: experimental model for human reactive arthritis?

Rats of five different strains were injected intravenously with live Yersinia enterocolitica O:8 or Yersinia pseudotuberculosis III. Twelve to 18 days after inoculation of Y. enterocolitica O:8, arthritic symptoms appeared in the hindpaws of SHR rats. They started with erythema, followed by swelling and painful movement, closely resembling findings in adjuvant arthritis. Histologically, the inflammation was dominated by neutrophils in two cases, whereas in two others the inflammatory cells were predominantly lymphocytes. Two of five rats yielded positive bacterial cultures from the joints. Altogether, arthritis was observed in five of nine SHR surviving beyond day 14 after the bacterial inoculation. Rats of Lewis, Wistar, WKY and Zucker strains did not develop any signs of arthritis after intravenous injection of Y. enterocolitica or pseudotuberculosis. Also in the SHR rats, Y. pseudotuberculosis failed to induce arthritis.

Animals↗
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↗
PubMed1986

Long-term effect of levamisole on the immune functions in melanoma patients.

Thirty radically operated patients with a locally advanced malignant melanoma were given adjuvant levamisole orally 50 mg three times a day on two days a week for one to 40 months in order to prevent recurrence of melanoma. During levamisole treatment the number of E- and EAC-rosette forming cells, proliferative responses of lymphocytes to phytohemagglutinin, concanavalin A and to purified protein derivative of tuberculin were followed at two to four month intervals. All patients were clinically followed at least for five years or to the recurrence of melanoma. Only slight variations occurred in the number of E- and EAC-rosette forming cells and in the responses to mitogens during levamisole treatment. Five out of 30 patients were alive without a recurrence at five years after starting adjuvant levamisole treatment. We conclude that adjuvant levamisole treatment is of no benefit in radically operated melanoma with satellites or metastases in the regional lymph nodes.

B-Lymphocytes↗
PubMed1986

Effect of tamoxifen on immune functions.

Tamoxifen (20 mg twice daily) was given to ten patients with breast cancer whose immune functions were determined prior to and 3, 6, and 12 months after starting tamoxifen therapy. No consistent changes could be observed in erythrocyte rosette-forming cell counts, erythrocyte antibody rosette-forming cells, active erythrocyte rosette-forming cells, theophylline-resistant rosette-forming cells, surface immunoglobulin-positive cells, and responses to mitogens phytohemagglutinin and concanavalin A. Erythrocyte antibody rosette-forming cells decreased significantly, however, at 6 months and active erythrocyte rosette-forming cells at 12 months after starting tamoxifen. We conclude that no change in the immune capacity could be detected during tamoxifen treatment.

Breast Neoplasms↗
PubMed1985

Immune functions and the prognosis of patients with solid tumours.

The immune competence of 169 patients with solid malignant tumours was assessed before initiation of radiotherapy or chemotherapy and followed during the course of the disease. The data of years 1974-1984 were collected and subjected to an analysis in order to evaluate their prognostic significance. The number of leucocytes and lymphocytes in the peripheral blood, the percentage or absolute number of E-rosette forming cells or EAC-rosette forming cells or serum immunoglobulin levels did not show any association with the prognosis. Lymphocyte proliferative responses to PHA, Con A and PPD as studied before initiation of the treatment did not correlate with recurrence or final prognosis of the disease, except that the responses to PPD were slightly lower in patients with recurrence of gynaecological cancer, melanoma or gastrointestinal cancer than in their respective control patients. In the values observed after the first treatment course a low response to PPD was associated with poor prognosis in patients with melanoma or gastrointestinal cancer. At the time of recurrent disease the PPD response showed an association with a poor final outcome in patients with gastrointestinal malignancy. Of the responses assessed less than 3 months before death due to cancer, only in patients with breast cancer were low Con A responses seen; in all patient groups the PHA responses decreased in the terminal patients. The results do not support the idea that the methods currently available should be routinely used in the follow-up of cancer patients; rather, they indicate the need to seek new methods for this purpose.

Adolescent↗
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↗
PubMed1984

Lymphocyte subpopulations in patients with breast cancer after postoperative radiotherapy.

The effects of radiotherapy on the immune competence of patients with mammary cancer was studied using enumeration of the various lymphocyte subpopulations as detected by monoclonal OKT antisera, lymphocyte proliferative responses to phytohemagglutinin, concanavalin A, purified protein derivative to tuberculin (PPD), and serum immunoglobulin levels. The tests were carried out in nine patients with newly diagnosed and operated mammary cancer before and after the radiation therapy, and 6 months later, and in ten patients whose mammary cancer had been diagnosed and treated at least 3 years earlier and who had remained tumor-free. The number of lymphocytes in the peripheral blood and the various T-cell subpopulations as well as the OKIa1 cells mostly representing B-cells decreased. The only population increasing were the OKM1-positive cells, mostly representing monocytes and null cells. As also described earlier, the responses to mitogens decreased because of the radiotherapy but recovered, except for the responses to PPD which remained low.

Aged↗
PubMed1984

B-L antigens (class II) of the chicken major histocompatibility complex control T-B cell interaction.

The detailed study of the genetic control of T-B cell interactions in the chicken has been hampered by the lack of defined major histocompatibility complex (MHC) recombinant chicken lines. In the present study we have used some recently described MHC recombinant chicken lines separating regions encoding antigens that are homologous to class I and class II antigens of mammals in adoptive bursa cell transfer experiments, in which bursa cells from newly hatched chicks were transplanted into cyclophosphamide (Cy)-treated chicks. Subsequent immunizations of the recipients with a thymus-dependent antigen (SRBC) and a thymus-independent antigen (Brucella abortus) showed that the generation of germinal centers in the spleen and the production of antibodies to SRBC required identity between donor and recipient class II antigens (B-L antigens), whereas response to Brucella antigen did not require identity at any of the known MHC loci of the chicken. The results thus reveal that also in the chicken class II (B-L) region genes encode cell-surface glycoproteins that serve as restriction elements in T-B cell cooperation.

Animals↗
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↗
PubMed1984

Role of Ia-positive cells in the lymphocyte responses to Yersinia.

Activation of T lymphocytes by an antigen requires joint recognition of the antigen and the class-II HLA determinants on the membrane of the antigen-presenting cells (APC). Patients with reactive arthritis exhibit a depressed lymphocyte transformation response to Yersinia, suggesting a possible immunoregulatory disturbance in these patients. In this study the role of Ia (class-II HLA antigen)-positive APC in the lymphocyte response to a complex antigen, whole Yersinia bacterium, was evaluated. The results demonstrate that Ia-positive cells are necessary for the T-lymphocyte response to Yersinia. The role of APC in the pathogenesis of reactive arthritis is discussed.

Antibodies, Monoclonal↗
PubMed1984

Immune function in patients with ovarian carcinoma treated with irradiation or with cytostatics.

The immunocompetence of 25 patients with ovarian cancer was followed up during and after radiation or chemotherapy, by using the number of lymphocytes, E-rosette-forming cells, and mitogen responses as parameters. In comparison with chemotherapy, the irradiation caused a profound and permanent immunosuppression. In patients treated with chemotherapy, the number of E-rosette-forming cells and the mitogen responses were fewer in the patients who developed recurrence or dissemination.

Adult↗
PubMed1984

Lymphocyte transformation responses to gram negative bacteria after Yersinia and Salmonella infection: the importance of enterobacterial common antigen for the response.

Increased lymphocyte transformation (LT) responses have been observed in Yersinia infections both against the causative bacterium and against other enterobacteria. The responses of patients with reactive arthritis are lower than those of non-arthritic patients. We have now studied the LT responses against several gram negative bacteria and against a pair of enterobacterial common antigen (ECA) positive and ECA negative Salmonella typhimurium strains in patients after Yersinia or Salmonella infection. The haptenic ECA alone seemed not to be responsible for the increased LT responses. We conclude that some other common antigenic determinants present on the bacteria are responsible for the LT response.

Antigens, Bacterial↗