Antigen

About: Antigen is a research topic. Over the lifetime, 170233 publications have been published within this topic receiving 6982342 citations. The topic is also known as: antibody generator & Antigen.

The influence of immunologically committed lymphoid cells on macrophage activity in vivo

Abstract: It has been shown that the immune response of mice to infection with L. monocytogenes gives rise to a population of immunologically committed lymphoid cells which have the capacity to confer protection and a proportionate level of delayed-type hypersensitivity upon normal recipients. The cells were most numerous in the spleen on the 6th or 7th day of infection, but persisted for at least 20 days. Further study revealed that the immune cells must be alive in order to confer protection, and free to multiply in the tissues of the recipient if they are to provide maximum resistance to a challenge infection. The antibacterial resistance conferred with immune lymphoid cells is not due to antibacterial antibody; it is mediated indirectly through the macrophages of the recipient. These become activated by a process which appears to depend upon some form of specific interaction between the immune lymphoid cells and the infecting organism. This was deduced from the finding that immune lymphoid cells from BCG-immunized donors, which were highly but nonspecifically resistant to Listeria, failed to protect normal recipients against a Listeria challenge unless the recipients were also injected with an eliciting dose of BCG. The peritoneal macrophages of animals so treated developed the morphology and microbicidal features of activated macrophages. It is inferred that acquired resistance depends upon the activation of host macrophages through a product resulting from specific interaction between sensitized lymphoid cells and the organism or or its antigenic products. Discussion is also made of the possibility that activation of macrophages could be dependent upon antigenic stimulation of macrophages sensitized by a cytophilic antibody.

IL-2: The First Effective Immunotherapy for Human Cancer

Abstract: The ability of IL-2 to expand T cells with maintenance of functional activity has been translated into the first reproducible effective human cancer immunotherapies. The administration of IL-2 can lead to durable, complete, and apparently curative regressions in patients with metastatic melanoma and renal cancer. The growth of large numbers of tumor-infiltrating lymphocytes with in vitro anti-cancer activity in IL-2 has led to the development of cell transfer therapies that are highly effective in patients with melanoma. The genetic modification of T cells with genes encoding αβ TCRs or chimeric Ag receptors and the administration of these cells after expansion in IL-2 have extended effective cell transfer therapy to other cancer types.

Microdroplet testing for HLA-A, -B, -C, and -D antigens. The Phillip Levine Award Lecture.

Abstract: The microdroplet lymphocyte cytotoxicity test is universally accepted as the standard test for HLA antigen determination. An update of the technical details of the test is given, based on the authors’ testing 160,000 persons. Methods for quality control of the test as well as reproducibility data are provided. International standardization of the specificities has been accomplished by seven international workshops and a continuous cell exchange involving testing of 108 cells since 1974 by as many as 180 laboratories. The test has recently become applicable to the detection of HLA-D determinants, previously thought to be detectable only by lymphocyte-determined (LD) tests. Purified peripheral blood lymphocytes are reacted with antisera from which HLA-A, -B, and -C antibodies have been removed. B lymphocytes were found to be smaller than T lymphocytes by Coulter counter sizing. The purity of cell suspensions enriched for B lymphocytes can be individually monitored, as shown by the reactions produced by 126 test samples. HLA-D antigens have a linkage disequilibrium with certain HLA-A and -B specificities as demonstrated by population and family studies. Haplotypes found in 34 parents of 18 families demonstrate the new haplotypes, which now consist of four antigens per haplotype. Studies of HLA-D frequencies in Caucasians, Negroes, and Orientals show a distinctive distribution in the races. B lymphocytes also appear to have an autoantigen against which autoantibodies are readily produced. The autoantibodies are more active against B than T lymphocytes and act most effectively at 5 C. Although they appear in many diseases, most notably in systemic lupus erythematosus, they also occur in 10% of normal males and females. In patients awaiting kidney transplants, antibodies against B lymphocytes are often found. Patients with cold B-cell antibodies (autoantibodies) were shown to have higher transplant survival rates than those with warm B-cell antibodies (allogeneic). Thus, in performing crossmatch tests it is now necessary to distinguish antibodies against T and B lymphocytes and those that react in cold and in warm conditions.

Treatment of metastatic melanoma with autologous CD4+ T cells against NY-ESO-1.

Abstract: We developed an in vitro method for isolating and expanding autologous CD4+ T-cell clones with specificity for the melanoma-associated antigen NY-ESO-1. We infused these cells into a patient with refractory metastatic melanoma who had not undergone any previous conditioning or cytokine treatment. We show that the transferred CD4+ T cells mediated a durable clinical remission and led to endogenous responses against melanoma antigens other than NY-ESO-1.

A quantitative immunochemical measure of the primary interaction between I BSA and antibody.

Abstract: Most qualitative and quantitative antibody tests measure secondary effects of primary antigen-antibody interactions. Some of these secondary effects are observed in vivo, such as the Arthus phenomenon and anaphylaxis; whereas some are observed in vitro, such as complement fixation, precipitation, erythrocyte agglutination, and hemolysis. These tests measure the capacity of an antiserum to produce the secondary effect selected as the indicator, but they do not always reflect the total antibody content of the antiserum with respect to the test antigen, since antibody in a given antiserum is heterogeneous with respect to the biological or physical effects it produces.1 Examples of diversity of antibody in a single antiserum are numerous even when considering one