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At least 19 recordsLinked to original sources
PubMed1976

Studies on the mechanism of specific immunological unresponsiveness. II. Immunological properties of lymphoid cells from normal, immunized and immunologically unresponsive mice transferred into lethally irradiated recipients.

The immunological capacity of lymphoid cells from mice rendered tolerant to high and low doses of BSA was investigated. The tolerance was induced by multiple injections of high and low doses of antigen through the period of 30 days. Lymph node and bone marrow cells from tolerant animals were transferred into lethally irradiated syngeneic recipients. After 10 days, when lymphoid organs of the recipients were repopulated with the injected cells, challenge injection of the same antigen incorporated into complete Freund's adjuvant was given. The immune response of the transferred cells in the recipients was evaluated by analysis of the specific antibodies in the sera. Lymphoid cells from donors rendered toloerant with high doses of antigen recovered their reactivity 20 days after the transfer to the level of reaction of normal cells. Lymphoid cells from donors receiving multiple injection of low doses of BSA remained tolerant after the transfer through the entire observation period. According to the cellular events in the donors during the period of tolerance induction, and the behaviour of the transferred lymphoid cells in the new recipients, it seems possible that tolerance induced with high doses of BSA corresponded to the B-cell tolerance, while low doses of antigen most likely induced tolerance of T-cell population. The possible cellular mechanisms of B and T-cell tolerance were discussed.

Animals↗
PubMed1977

Biological and immunological characterization of human luteinizing hormone: II. A comparison of the immunological and biological activities of pituitary extracts after electrofocusing using different standard preparations.

The profile of immunologically active human luteinizing hormone (hLH) was determined in aqueous pituitary extracts after electrofocusing using two radioimmunoassay systems and the estimates for each fraction were compared to those obtained by an in vitro bioassay method. Similar biological and immunological profiles were obtained in the pH 7.0-9.0 region, where most of the biological activity was present. Biological to immunological (B/I) ratios ranging from 0.6 to 1.7 (mean ratio 1.01; n = 21) were found in the major biologically active fractions of this pH region when a highly purified human pituitary LH preparation (68/40) was used as standard in both types of assays. The close proximity of these ratios to unity indicates a similar composition of biological and immunological activities in all these fractions in relation to that of the highly purified standard. However, marked discrepancies were observed in the pH region 3.0-7.0 where the B/I ratios ranged from 0.1 to 0.9, indicating the presence of immunological activity associated with relatively little biological activity. When impure human LH preparations of pituitary (69/104) and urinary (hMG 2nd IRP) origin were used as standards for the bioassay and radioimmunoassay of the hLH present in the major fractions of the pH region 7.0-9.0, significantly higher B/I ratios were obtained than with the use of the highly purified standard (68/40). These elevated B/I ratios are attributed to the presence in the impure standard preparations of immunological activity, which is associated with little or no biological activity. These observations may provide an explanation for the differences in B/I ratios which were reported for hLH in plasma, using different standard preparations.

Biological Assay↗
PubMed1979

Immunological surveillance against neoplasia: an immunological quandary.

Immunological endeavor in recent years calls for a reappraisal of the concept of immunosurveillance against neoplasia. This concept proposes an immunological policing system capable of aborting tumor growth by the recognition of "nonself" tumor associated antigens on neoplastic cells. The model is supported by evidence of tumor induction in the immunosuppressed host and the demonstration of an immune response to tumors in animals. The occurrence of tumor, regarded as a failure of immunosurveillance, is attributed to selection of neoplastic cells for immunological or other reasons or abnormal humoral or cellular antitumor immune responses. However protagonists of the postulate are faced with mounting evidence that fails to support the surveillance hypothesis. These observations include, inter alia, the monoclonality of certain tumors, the low incidence of spontaneous tumors in genetically immunodeficient mice and immunological privileged sites, and new ideas about the pathogenesis of lymphoproliferative neoplasms. However, contradictory arguments are not sufficiently substantiated to prosecute the case against surveillance conclusively. In citing highlights of the evolving quandary, both the pros and cons of immunological surveillance are presented here.

Animals↗
PubMed1978

Biological and immunological characterization of human luteinizing hormone: IV. Biological and immunological profile of two international reference preparations after electrofocusing.

The first IRP of Human Pituitary Gonadotrophins (FSH/LH) for bioassay (69/104) and the 1st IRP of Human Pituitary Luteinizing Hormone (LH) for immunoassay (68/40) were fractionated by an electrofocusing technique in a sucrose density gradient and the profile of biological and immunological activities was determined. The partially purified LH preparation (69/104) gave a broad pattern of biolgical and immunological activities which extended from pH 4 to 10. The biological : immunological (B/I) ratio of the various fractions (using the 68/40 preparation as standard) ranged from 0.04 to 1.05. The low B/I ratios indicate the presence of high levels of immunologically active, biologically inactive material in this preparation. In contrast to the behaviour of the 69/104 preparation, the major proportion (88%) of the biological activity recovered after electrofocusing of the highly purified LH preparation (68/40) was found within the pH range 7--9, with B/I ratios (again using as standard the 68/40 preparation) ranging from 0.4 to 1.5. Multiple dose parallel line design radioimmunoassays revealed a lack of parallelism between the 69/104 and 68/40 International Reference Preparations. This was attributed to the presence of acidic material in the former preparation, which is practically absent from the latter. The biological LH profiles of both the 69/104 and 68/40 preparations differed from those previously reported for aqueous extracts of pituitaries. It is concluded that the dissimilarity in the electrofocusing profiles of the biological and immunological activities of the 69/104 preparation renders this preparation unsuitable as a reference preparation for the quantitation of biologically active LH by radioimmunoassay methods. Using the same criteria, the 68/40 preparation would appear to be a more suitable standard.

Animals↗
PubMed1978

Modification of prostaglandin and thromboxane release by immunological sensitisation and successive immunological challenges from guinea-pig lumg.

The release of prostaglandins (PGs) and thromboxanes (Txs) from perfused guinea pig lungs was investigated during different immunological states. The major product released from normal lungs perfused with exogenous arachidonic acid was 6-oxo-PGF1a. The procedure of sensitisation to specific antigen resulted in an increase in the release of 15-oxo-13,14-dihydro-TxB2 and a decrease in the release of 6-oxo-PGF1a- and 6,15-dioxo-13,14-dihydro-PGF1a from lungs perfused with arachidonic acid. The relative amount of 15-oxo-13,14-dihydro-TxB2 released progressively increased with the number of immunological challenges with both exogenous and endogenously derived substrate, arachidonic acid. This change in response to successive immunological challenges may represent a protective mechanism to prevent parent Txs and PGs entering the systemic circulation.

Anaphylaxis↗
PubMed1978

Multi-system immunologically mediated disease: T lymphocyte deficiency and thyroid immunologic disease--a report of four cases.

Four cases are described of multi-system immunologically-mediated disease (systemic lupus erythematosus (two cases), polymyositis, and sarcoidosis) in association with thyroid autoimmunity. In all patients there was evidence of T lymphocyte deficiency, namely poor response of peripheral blood lymphocytes (PBL) to T cell mitogens (four cases) and failure or decreased ability to become sensitized to dinitrochlorobenzene (three cases), although two patients were ill and two were being treated with steroids. There was also evidence of B lymphocyte deficiency since PBL of no patient responded normally to pokeweed mitogen, a B and T lymphocyte mitogen. In two patients there was evidence of cell-mediated immunity to human thyroid antigens. Although thyroid stimulating antibody was not detected in the one patient with Graves' disease tested, significant titres of thyroid antibodies were detected in all cases. Possible relationships between T lymphocyte deficiency, organ-specific autoimmune disease and immunologically-mediated multi-system disorders are discussed.

Adult↗
PubMed1976

Immunological and non-immunological mechanisms of some of the desirable and undesirable effects of anti-inflammatory and analgesic drugs.

Studies were carried out on patients with adverse reactions to aspirin, paracetamol, phenacetin, codeine, dihydrocodeine, some pyrazolone derivatives, and indomethacin. Three clinico-pathological forms of adverse reactions received particular attention: (1) Asthma, with or without manifestations of systemic anaphylaxis; (2) Serum-sickness-like syndrome; (3) Lymph node enlargement with histological features simulating lymphoma or Hodgkin's disease, which occurred in patients receiving phenylbutazone in particular. A variety of immunological investigations, including some in vitro correlates of immediate- or delayed-type allergy, were carried out. The three syndromes seemed to be associated with immediate-type (or immediate-type-like), immediate-type plus delayed-type, and delayed-type allergy, respectively. In most of the patients with immediate-type-like reactions, and where immunological mechanisms were apparently not involved, pharmacological mediators, particularly histamine, were released from their leucocytes when challenged in vitro with the causative agent(s). This suggested that the main underlying abnormality of their asthma or peripheral vascular manifestations was a direct release of mediators by the drugs, i.e. some type of idiosyncrasy. The causative mechanism of this abnormality has not been established yet.

Anaphylaxis↗
PubMed1977

Sequential immunologic stimuli to the respiratory tract: a paradox in the degree of potentiation of airway responses depending on the sequence of reverse passive and active immunologic stimulation.

Immunologic stimuli to the airway of rhesus monkeys were given by aerosol challenge with ascaris antigen or anti-IgE. Both of these stimuli produce immediate-type airway responses. When 2 sequential aerosol challenges were given during the same experiment, the response following the second stimulus was always less than or equal to the first response following any combination of stimuli except the anti-IgE-ascaris sequence. The second response following the latter challenge was always greater than or equal to the first response. The possibility that this exception was the result of anti-IgE priming mediator releasing cells for antigen was not supported by in vitro experiments. It is suggested that the results obtained with the anti-IgE-ascaris sequence may relate to the presence of intralumenal mast cells in the bronchi and the molecular weights of the 2 immunologic stimuli.

Animals↗
PubMed1978

Immunological experimental arthritis in pigs. V. Reaction of the synovial membrane in the pigs non-immunized and immunized with the virus of Aujeszky's disease after the intraarticular administration of the immunological complexes.

Immunized animals were given intraarticular complexes formed in vitro from the autologous serum and virus AD. 7 days after complex administration with excess of the virus, weak inflammatory reactions of the immunological type were noted. After neutral complex administration virulent immunological inflammation of the synovial membrane took place. The histological picture resembled rheumatoid arthritis in the man and the changes obtained after the virus administration to the joints with a high level of antibodies. Administration of complexes and homological serum alone to the joints of the nonimmunized animals caused the occurrence of superficial focuses of fibrinoid necrosis, but there was a lack of cellular reactions.

Animals↗
PubMed1979

[Immunology of pregnancy -- more recent aspects of immunological mother-child relations (author's transl)].

An account is given of some topical aspects relating to immunology of pregnancy, with reference being made to more recent literature. Included are hypothetical considerations on undisturbed embryonic development, the barrier function of the placenta, the ontogenesis of the immune system, immunosuppressive factors of pregnancy serum, the macrophage function of placental cells, pregnancy proteins, and immunological peculiarities of EPH gestosis.

Antibody Formation↗
PubMedDate not supplied

Current concepts of tumor immunology. I. Basic immunologic concepts.

Interest in tumor immunology grew out of the study of host response to microbial infections during the second half of the 19th century. However, the growth of interest in transplantation during the 1950s and 1960s is largely responsible for the great surge of scientific investigation into tumor immunobiology which we are experiencing today. Tumor cells possess certain abnormal antigens in addition to their normal complement of transplantation antigens. These abnormal antigens evoke an immune response in the host, which involves both the humoral and the cell-mediated systems. Though the cell-mediated (thymus derived) system is generally conceded the most important role in tumor cell destruction, the humoral (bursal-equivalent derived) system also plays a role in host response which is presently less clearly understood. Certain aspects of the humoral response (blocking factors) actually appear to inhibit the host response against a tumor. This complex system of host immune response to tumor has been termed the immunosurveillance system.

Animals↗
PubMed1976

The immunologic system, immunologic deficiency disorders and lymphoid hyperplasia of the small intestine.

The purpose of this paper is to review our current concept of the systems that subserve immunological functions. It concerns specifically the immunodeficiency diseases probably due to a B cell immunodeficiency. An attempt is made to classify those diseases clinically as well as roentgenologically. At last using the enteroclysis technique some examples of immunodeficiency syndromes are shown with special emphasis on developing a malignant disease.

Animals↗
PubMed1976

Immunological and non-immunological phagocytosis by inflammatory macrophages, epithelioid cells and macrophage polykaryons from foreign body granulomata.

Inflammatory macrophages, epithelioid cells and macrophage polykaryons were obtained on the surface of round glass coverslips inserted into the subcutaneous tissue of mice and removed at different intervals. About 90 per cent of the macrophages and polykaryons express IgG, C and non-specific surface receptors, involved in phagocytosis, up to 15 days after coverslip implantation. In 21-day-old lesions, about 50 per cent of these cells lose the IgG resed with IgM and complement but do not incorporate these particles and are poorly phagocytic for glutaraldehyde-treated horse red blood cells. The ultrastructural study of these cells demonstrates that they are macrophages which have undergone epithelioid transformation. Whole-body irradiation of mice bearing implanted coverslips of 7 days duration reveals that 6 days after irradiation, the great majority of macrophages and multinucleate cells have acquired epithelioid characteristics. It is suggested that the loss of immunological receptors during epithelioid transformation in granulomas may protect bacteria and be disadvantageous to the host.

Age Factors↗
PubMed1978

Immunological properties of membrane-bound adenosine triphosphatase: immunological identification of rutamycin-sensitive F0.F1ATPase from Micrococcus luteus ATCC 4698 established by crossed immunoelectrophoresis.

(1) F0.F1ATPase (EC 3.6.1.3) from Micrococcus luteus ATCC 4698 was solubilized from plasma membranes by the non-ionic detergent Triton X-100 in the presence of 0.05 M MgCl2. (2) The antibiotics rutamycin, Dio-9, quercetin, oligomycin, botrycidin, efrapeptin, leucinostatin, valinomycin, and venturicidin as well as N,N'-dicyclohexylcarbodiimide and dinitrophenol are potent inhibitors of F0.F1ATPase activity.(3) F0.F1ATPase activity is completely inhibited by anti-F1ATPase antibodies. The inhibition is non-competitive. (4) Crossed immunoelectrophoresis reveals a reaction of immunological identity of F0.F1ATPase and F1ATPase indicating that both enzymes have in common antigenic sites.

Adenosine Triphosphatases↗
PubMed1976

Secretory immunological system of fowl. V. The gallbladder: an integral part of the secretory immunological system of fowl.

The concentrations of IgA, IgM and IgY were measured in gallbladder (GB) bile and serum from chickens of various ages. The ontogeny data suggested that IgA and IgY were synthesized by the GB. Furthermore, the chicken GB becomes lymphoid 3-8 days post-hatch and contains distinct foci of lymphocytes by 7 weeks of age. That the GB can synthesize and secrete IgA was shown in two ways. IgA-containing cells were demonstrated by immunofluorescence and in vitro studies with adult GB explants showed the synthesis and secretion of IgA and also IgY and IgM. Immunoglobulin class suppression experiments and quantitation of IgA in sera from selected sites supported the concept of synthesis and secretion of IgA by the GB. Several lines of evidence also support the concept of some bile IgA being derived from serum. Introduction of antigen directly into the GB was shown to stimulate antibody formation, and this antibody was detectable in bile and serum. A very unusual finding, in one animal, was the presence of a normal secretory IgA concentration in the presence of undetectable serum IgA. These data indicate that the GB is an integral part of the secretory immunological system and suggest that aberrations in GB-immune function may result in pathological clinical manifestations.

Aging↗
PubMed1976

Immunologic protection of rabbit corneal allografts with heterologous 'blocking' antibody. Immunologic protection of corneal allografts.

Exchange penetrating keratoplasties were performed in NZW rabbits using conreas soaked in heterologous 'blocking' antibody (guinea pig anti-rabbit gamma-globulin) under various experimental situations and immunogenic stimuli. Results suggest that the antibody can protect the rabbit graft from weak rejection stimuli possibly by blocking the afferent arc of the immunologic reflex, but cannot protect the graft from presensitization, or nonocular sensitization. The use of a blocking antibody in human transplantation would be simple and of slight risk to a graft recipient.

Animals↗