### cell:

T cell
* All T cells originate from haematopoietic stem cells in the bone marrow.
* activated by zwitterionic molecules prevent abscesses induced by pathogenic bacteria.
* are able to recognise virus infected cells early in the infection process
  - absent as are peripheral T cells and B lymphocytes
  - an important part of the immune system and aid in fighting disease
* are essential for cell-mediated immunity
  - disease development
  - important in the development of some autoimmune diseases, including multiple sclerosis
  - key cells that coordinate immune system response
* are lymphocytes or cells of the lymphatic system
  - which develop in the thymus
* are part of the natural defense system of the body
  - what is known as the cancer-immunity cycle
  - primed in the thymus, where they undergo two selection processes
  - produced in the bone marrow and later move to the thymus where they mature
  - specialized white blood cells mobilized by the immune system to destroy foreign cells
  - that part of the immune system which turn an immune response on and off
* are the cells which control and regulate the immune response
  - quarterback of the immune system
* are the white blood cells that fight infections
  - orchestrate the immune response
  - what vaccines ultimately activate and produce
  - white blood cells which fight infection
* are, in fact, special kinds of white blood cells.
* attach to the invading cell and kill it directly, cell mediated destruction of the invader.
* attack a. cells that are infected with viruses
  - when they are exposed to small amounts of an antigen
* become specific killers when presented with protein cues.
* can also produce memory cells with an even longer life span than B memory cells
  - be helper cells or killer cells
  - live for months to years
  - prevent the rapid evolution of lung fibrosis
  - represent an exclusive means of immunopathology in a virus infection
  - respond vigorously in vitro to previously encountered antigens
* come in many varieties
  - to attack the virus and are killed
  - two different types, helper cells and killer cells
* contribute to control of chronic parasitemia in Plasmodium chabaudi infections in mice.
* contribute to the body's defenses in two major ways
  - control of infection
  - immune defenses in two major ways
* deal with intracellular parasites, typically viruses.
* defend the body from microbes by interacting with another immune system cell
  - potentially deadly pathogens such as bacteria, viruses, and fungi
* destroy cells marked by antibodies or expressing specific antigens.
* develop in an organ called the thymus.
* direct the immune response.
* do, however, readily squeeze through the vascular endothelium without any loss of integrity.
* express a clonal antigen-specific receptor.
* function in the cell-mediated immune response iii.
* have receptors which are generated by randomly shuffling gene segments
  - several functions
* help in various other ways.
* induce acute pancreatitis and diabetes in immune-compromised NOD mice
  - terminal differentiation of transformed B cells to mature plasma cell tumors
* infiltrate the pancreas and destroy the beta-cells in the islets of langerhans.
* is compatible with normal ovarian function in mice
  - geared toward regulation rather than immune response
* lead the immune response against infections.
* lymphocytes' job is to scan cells for infection.
* mature in bone marrow, and B cells mature in the thymus.
* mature in the thymus gland, which lies on the heart
* mediate cellular reactions
  - delayed hypersensitivity by releasing various lymphokines
* mediated hypersensitivity is responsible for prevention of the disease.
* play a cardinal role in regulating the immune system
  - critical role in costimulation blockade-resistant allograft rejection
  - key role in combating most viral infections
  - large role in our fight against cancer
* play an important role in acute experimental pancreatitis in mice
  - in vivo rejection of human melanoma
  - critical roles in host immune responses to pathogens
* produce a large group of cytokines known as interleukins
  - antibodies in response to specific antigens on the surface of foreign cells
  - antiviral cytokines but are impaired in cytolytic function
  - proteins called lymphokines, which are one type of cytokine
* proliferate before they differentiate into effector cells.
* provide for desirable outcomes such as protection from pathogens and tumours.
* recognize and kill infected cells
  - antigen only in the context of other proteins found on cell surfaces
  - only fragments of proteins bound to histocompatibility proteins
* regulate the immune system's response to infections.
* reproduce through a process known as mitosis, in which the cells split in two.
* require tryptophan for their proliferation
  - two signals to become activated
* respond to antigens exposed on the surfaces of macrophages.
* responses to the parent tumor, and thereby serve as immunotherapeutic vaccines.
* see antigen in a different way to B cells.
* seek and destroy cells containing viruses.
* serve two roles.
* start in the marrow but migrate through the bloodstream to the thymus and mature there.
* take their name.
* undergo metabolic reprogramming after they are activated.
* work in both direct and indirect ways to fight cancer
  - on cell-mediated immune responses
  - primarily by producing proteins called lymphokines