cell-mediated immunity

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cell-·me·di·at·ed im·mu·ni·ty (CMI),

, cellular immunity
Immune responses mediated by activated, antigen-specific T lymphocytes. These T cells may function as effector cells or may orchestrate propagation of the inflammatory response and cellular recruitment through their secretion of cytokines and chemokines.
Synonym(s): delayed hypersensitivity (1)

cell-mediated immunity

n.
Immunity resulting from a cell-mediated immune response. Also called cellular immunity.

cell-me·di·at·ed im·mu·ni·ty

, cellular immunity (CMI) (sel'mē'dē-āt-ĕd i-myū'ni-tē, sel'yū-lăr)
Immune responses that are initiated by T lymphocytes and mediated by T lymphocytes, macrophages, or both (e.g., graft rejection, delayed-type hypersensitivity).
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CELL-MEDIATED IMMUNITY

cell-mediated immunity

Abbreviation: CMI.
The regulatory and cytotoxic activities of T cells during the specific immune response. This process requires about 36 hr to reach its full effect. Synonym: T-cell–mediated immunity See: illustration; humoral immunity

Unlike B cells, T cells cannot recognize foreign antigens on their own. Foreign antigens are recognized by antigen-presenting cells (APCs) such as macrophages, which engulf them and display part of the antigens on the APC's surface next to a histocompatibility or “self-” antigen (macrophage processing). The presence of these two markers, plus the cytokine interleukin-1 (IL-1) secreted by the APCs activates CD4 helper T cells (TH cells), which regulate the activities of other cells involved in the immune response.

CMI includes direct lysis of target cells by cytotoxic T cells, creation of memory cells that trigger a rapid response when a foreign antigen is encountered for the second time, and delayed hypersensitivity to tissue and organ transplants. T cells also stimulate the activity of macrophages, B cells, and natural killer cells. These functions are controlled largely by the secretion of lymphokines such as the interleukins, interferons, and colony-stimulating factors. Lymphokines facilitate communication and proliferation of the cells in the immune system.

See also: immunity

cell-mediated immunity

Action by the immune system involving T cells (T LYMPHOCYTES) and concerned with protection against viruses, fungi, TUBERCULOSIS and cancers and rejection of foreign grafted material. Cell-mediated immunity is not primarily effected by ANTIBODIES.
References in periodicals archive ?
In conclusion, the large majority of our knowledge on the mechanisms leading to human NK cell-mediated porcine endothelial cell recognition and destruction was generated in vitro.
As an indicator of susceptibility to infectious disease, cell-mediated immunity was measured by antibody response to three vaccines and skin prick tests, white blood cell count, and self-reported illness.
Caption: The authors concluded that their findings indicated that cell-mediated immunity is affected by the herpes zoster vaccine and enhanced by a stronger, or more recent, dose.
Combined IgE- and cell-mediated food allergic conditions
This study estimated the NK cell-mediated cytotoxicity of mice which is treated by MBGS and, furthermore, used the tumor-bearing murine model of inducing the metastasis from the primary tumor by radiation [12] and observes for the effectiveness of MBGS in conjunction with the radiation therapy to control cancer metastasis.
Practically all forms of immunity are affected by protein-energy malnutrition, but non-specific defences and cell-mediated immunity are most severely affected.
The groups were acute T cell-mediated rejection group (group A, 27 cases), chronic active antibody-mediated rejection group (group B, 9 cases), chronic active T cells mediated rejection group (group C, 5 cases), borderline lesions group (group D, 13 cases), normal group without obvious acute rejection or injury of immunosuppressant toxicity (group E, 11 cases), and recurrence of allograft nephropathy group (group F, 4 cases).
These are then presented to naive T cells in the locoregional lymph nodes, which then stimulates even more of a cell-mediated immune response and inflammatory response that then further increases apoptosis of local cells," Dr.
Ultra violet radiation from the sun initiates DNA damage in skin cells and suppresses cell-mediated immunity, allowing sun-damaged cells and cancer cells to escape immune destruction.
The procedure was approved by the US Food and Drug Administration in 1988 as the first cellular immunotherapy for cancer, and since then has been investigated for preventing and treating a variety of T cell-mediated diseases, including acute and chronic graft-versus-host disease, solid organ and tissue transplantation, systemic sclerosis, systemic lupus erythemotades, rheumatoid arthritis, Crohn's disease, and diabetes mellitus.
Dean Bottino, Head Modeling & Simulation Oncology, Roche Pharmaceuticals, will present a webinar entitled “Multi-scale modeling to optimize the antitumor effect of antibody-dependent cell-mediated cytotoxicity (ADCC) enhanced therapies” on Wednesday, June 19, 2013 at 1:00 - 2:00 pm EDT.
The deal includes the acquisition of Cylex's core product, ImmuKnow, a noninvasive biomarker ofimmune function that assesses cellular immune status by detecting cell-mediated immunity (CMI) in populations undergoing immunosuppressive therapy for an organ transplant.