In cell biology, a lymphokine-activated killer cell (also known as a LAK cell) is a white blood cell, consisting mostly of natural killer, natural killer T, and T cells that has been stimulated to kill tumor cells, but because of the function in which they activate, and the cells they can successfully target, they are classified as different than the classical natural killer and T lymphocyte systems.
It has been shown that when Peripheral blood leukocytes (PBL) are cultured in the presence of Interleukin 2, it results in the development of effector cells, which are cytotoxic and are seen to localize to tumor sites and are capable of lysing fresh, non-cultured cancer cells, both primary and metastatic. [1] LAK cells respond to these lymphokines, particularly IL-2, by developing into effector cells capable of lysing tumor cells that are known to be resistant to NK cell activity. After stimulated by IL-2, LAK cells can target and kill tumor cells in the early innate response. [2]
The mechanism of LAK cells is distinctive from that of natural killer cell because they can lyse cells that an NK cell cannot. LAK cells are also capable of acting against cells that do not display the major histocompatibility complex, as has been shown by the ability to cause lysis in non-immunogenic, allogeneic and syngeneic tumors. LAK cells function in the same way as NK cells in the peripheral blood but are more sensitive to and can target tumor cells.
The use of LAK cells has been found to be helpful in treating human cells with different cancers in vitro [3] . LAK cell therapy is a method that uses interleukin 2 (IL-2) to enhance the number of lymphocytes in an in vitro setting, and it has formed the foundation of many immunotherapy assays that are now in use. [4] LAK cells have shown potential as a cellular agent for cancer therapy and have been utilized therapeutically in association with IL-2 for the treatment of various cancers. LAK cells have anticancer efficacy against homologous carcinoma cells and can grow ex vivo in the presence of IL-2. [5] In melanoma and gastric cancer cells, intercellular adhesion molecule 1 (ICAM-1) antibody can significantly inhibit in vitro LAK-induced lysis of cancer cells. A study has shown that ICAM1 in lung cancer cells increases LAK cell-mediated tumor cell death as a new anti-tumor mechanism. [6] One study uses a 4 hour chromium release assay, which is an assay used to measure the cytotoxicity of T cells and natural killer cells, to measure lysis of the fresh solid tumor cells from 10 cancer patients and found that in all 10 cancer patients the fresh autologous tumor cells were resistant to lysis by PBL with natural killer cells, but were lysed by the LAK cells. [2]
LAK cells, along with the administration of IL-2 have been experimentally used to treat cancer in mice and humans, but there is very high toxicity with this treatment - Severe fluid retention was the major side effect of therapy, although all side effects resolved after interleukin-2 administration was stopped. Treatment of IL-2 cells by themselves to treat cancers are more dangerous than treatment with the combination of IL-2 and LAK cells. [7]
Natural killer cells, also known as NK cells or large granular lymphocytes (LGL), are a type of cytotoxic lymphocyte critical to the innate immune system. They belong to the rapidly expanding family of known innate lymphoid cells (ILC) and represent 5–20% of all circulating lymphocytes in humans. The role of NK cells is analogous to that of cytotoxic T cells in the vertebrate adaptive immune response. NK cells provide rapid responses to virus-infected cells, stressed cells, tumor cells, and other intracellular pathogens based on signals from several activating and inhibitory receptors. Most immune cells detect the antigen presented on major histocompatibility complex I (MHC-I) on infected cell surfaces, but NK cells can recognize and kill stressed cells in the absence of antibodies and MHC, allowing for a much faster immune reaction. They were named "natural killers" because of the notion that they do not require activation to kill cells that are missing "self" markers of MHC class I. This role is especially important because harmful cells that are missing MHC I markers cannot be detected and destroyed by other immune cells, such as T lymphocyte cells.
Immunotherapy or biological therapy is the treatment of disease by activating or suppressing the immune system. Immunotherapies designed to elicit or amplify an immune response are classified as activation immunotherapies, while immunotherapies that reduce or suppress are classified as suppression immunotherapies. Immunotherapy is under preliminary research for its potential to treat various forms of cancer.
Interleukin-2 (IL-2) is an interleukin, a type of cytokine signaling molecule in the immune system. It is a 15.5–16 kDa protein that regulates the activities of white blood cells (leukocytes, often lymphocytes) that are responsible for immunity. IL-2 is part of the body's natural response to microbial infection, and in discriminating between foreign ("non-self") and "self". IL-2 mediates its effects by binding to IL-2 receptors, which are expressed by lymphocytes. The major sources of IL-2 are activated CD4+ T cells and activated CD8+ T cells. Put shortly the function of IL-2 is to stimulate the growth of helper, cytotoxic and regulatory T cells.
This is a list of AIDS-related topics, many of which were originally taken from the public domain U.S. Department of Health Glossary of HIV/AIDS-Related Terms, 4th Edition.
Interleukin 12 (IL-12) is an interleukin that is naturally produced by dendritic cells, macrophages, neutrophils, helper T cells and human B-lymphoblastoid cells (NC-37) in response to antigenic stimulation. IL-12 belongs to the family of interleukin-12. IL-12 family is unique in comprising the only heterodimeric cytokines, which includes IL-12, IL-23, IL-27 and IL-35. Despite sharing many structural features and molecular partners, they mediate surprisingly diverse functional effects.
Interferon gamma is a dimerized soluble cytokine that is the only member of the type II class of interferons. The existence of this interferon, which early in its history was known as immune interferon, was described by E. F. Wheelock as a product of human leukocytes stimulated with phytohemagglutinin, and by others as a product of antigen-stimulated lymphocytes. It was also shown to be produced in human lymphocytes. or tuberculin-sensitized mouse peritoneal lymphocytes challenged with Mantoux test (PPD); the resulting supernatants were shown to inhibit growth of vesicular stomatitis virus. Those reports also contained the basic observation underlying the now widely employed interferon gamma release assay used to test for tuberculosis. In humans, the IFNG protein is encoded by the IFNG gene.
Antibody-dependent cellular cytotoxicity (ADCC), also referred to as antibody-dependent cell-mediated cytotoxicity, is a mechanism of cell-mediated immune defense whereby an effector cell of the immune system kills a target cell, whose membrane-surface antigens have been bound by specific antibodies. It is one of the mechanisms through which antibodies, as part of the humoral immune response, can act to limit and contain infection.
Interleukin-1 beta (IL-1β) also known as leukocytic pyrogen, leukocytic endogenous mediator, mononuclear cell factor, lymphocyte activating factor and other names, is a cytokine protein that in humans is encoded by the IL1B gene. There are two genes for interleukin-1 (IL-1): IL-1 alpha and IL-1 beta. IL-1β precursor is cleaved by cytosolic caspase 1 to form mature IL-1β.
The following are notable events in the Timeline of immunology:
Interleukin-15 (IL-15) is a protein that in humans is encoded by the IL15 gene. IL-15 is an inflammatory cytokine with structural similarity to Interleukin-2 (IL-2). Like IL-2, IL-15 binds to and signals through a complex composed of IL-2/IL-15 receptor beta chain (CD122) and the common gamma chain. IL-15 is secreted by mononuclear phagocytes following infection by virus(es). This cytokine induces the proliferation of natural killer cells, i.e. cells of the innate immune system whose principal role is to kill virally infected cells.
Interleukin 21 (IL-21) is a protein that in humans is encoded by the IL21 gene.
CD16, also known as FcγRIII, is a cluster of differentiation molecule found on the surface of natural killer cells, neutrophils, monocytes, macrophages, and certain T cells. CD16 has been identified as Fc receptors FcγRIIIa (CD16a) and FcγRIIIb (CD16b), which participate in signal transduction. The most well-researched membrane receptor implicated in triggering lysis by NK cells, CD16 is a molecule of the immunoglobulin superfamily (IgSF) involved in antibody-dependent cellular cytotoxicity (ADCC). It can be used to isolate populations of specific immune cells through fluorescent-activated cell sorting (FACS) or magnetic-activated cell sorting, using antibodies directed towards CD16.
CD226, PTA1 or DNAM-1 is a ~65 kDa immunoglobulin-like transmembrane glycoprotein expressed on the surface of natural killer cells, NK T cell, B cells, dendritic cells, hematopoietic precursor cells, platelets, monocytes and T cells.
The Interleukin-2 receptor alpha chain is a protein involved in the assembly of the high-affinity Interleukin-2 receptor, consisting of alpha (IL2RA), beta (IL2RB) and the common gamma chain (IL2RG). As the name indicates, this receptor interacts with Interleukin-2, a pleiotropic cytokine which plays an important role in immune homeostasis.
Autologous immune enhancement therapy (AIET) is a treatment method in which immune cells are taken out from the patient's body which are cultured and processed to activate them until their resistance to cancer is strengthened and then the cells are put back in the body. The cells, antibodies, and organs of the immune system work to protect and defend the body against not only tumor cells but also bacteria or viruses.
Natural killer T (NKT) cells are a heterogeneous group of T cells that share properties of both T cells and natural killer cells. Many of these cells recognize the non-polymorphic CD1d molecule, an antigen-presenting molecule that binds self and foreign lipids and glycolipids. They constitute only approximately 1% of all peripheral blood T cells. Natural killer T cells should neither be confused with natural killer cells nor killer T cells.
The NK-92 cell line is an immortalised cell line that has the characteristics of a type of immune cell found in human blood called ’natural killer’ (NK) cells. Blood NK cells and NK-92 cells recognize and attack cancer cells as well as cells that have been infected with a virus, bacteria, or fungus. NK-92 cells were first isolated in 1992 in the laboratory of Hans Klingemann at the British Columbia Cancer Agency in Vancouver, Canada, from a patient who had a rare NK cell non-Hodgkin-lymphoma. These cells were subsequently developed into a continuously growing cell line. NK-92 cells are distinguished by their suitability for expansion to large numbers, ability to consistently kill cancer cells and testing in clinical trials. When NK-92 cells recognize a cancerous or infected cell, they secrete perforin that opens holes into the diseased cells and releases granzymes that kill the target cells. NK-92 cells are also capable of producing cytokines such as tumor necrosis factor alpha (TNF-a) and interferon gamma (IFN-y), which stimulates proliferation and activation of other immune cells.
Cytokine-induced killer cells (CIK) cells are a group of immune effector cells featuring a mixed T- and natural killer (NK) cell-like phenotype. They are generated by ex vivo incubation of human peripheral blood mononuclear cells (PBMC) or cord blood mononuclear cells with interferon-gamma (IFN-γ), anti-CD3 antibody, recombinant human interleukin (IL)-1 and recombinant human interleukin (IL)-2.
Thomas A. Waldmann was an American immunologist who has worked on therapeutic monoclonal antibodies to the IL-2 receptor, Interleukin 15 (IL-15), and Adult T-cell Leukemia (ATL). Until the week he died, he was an active distinguished investigator at the Lymphoid Malignancies Branch of the National Cancer Institute.
Cellular adoptive immunotherapy is a type of immunotherapy. Immune cells such as T-cells are usually isolated from patients for expansion or engineering purposes and reinfused back into patients to fight diseases using their own immune system. A major application of cellular adoptive therapy is cancer treatment, as the immune system plays a vital role in the development and growth of cancer. The primary types of cellular adoptive immunotherapies are T cell therapies. Other therapies include CAR-T therapy, CAR-NK therapy, macrophage-based immunotherapy and dendritic cell therapy.