Table of Contents
Effector Cells Definition
Effector Cell – Definition Activation Process Types and Function.
There are two types of effector cells:
- T cells: T cells are lymphocytes that originate in the thymus. They are responsible for cell-mediated immunity, which is the immune response that occurs when a cell is infected with a virus or other pathogen. The T cells recognize and destroy the infected cells.
- B cells: B cells are lymphocytes that originate in the bone marrow. They are responsible for antibody-mediated immunity, which is the immune response that occurs when an antibody binds to a pathogen. The B cells produce antibodies that destroy the pathogen.
Effector T Cell Generation
Effector T cells are generated in the thymus, where they mature from naive T cells. Naive T cells are created in the bone marrow, and then migrate to the thymus, where they undergo several rounds of cell division. During this process, the naive T cells acquire the ability to recognize and respond to specific antigens. The effector T cells then exit the thymus and migrate to the lymph nodes and other organs, where they mount an immune response to the antigen.
Production of T cell receptor
T cell receptor is produced on the surface of a T cell. It is a glycoprotein molecule made up of two chains, a heavy chain and a light chain. The heavy chain is the same for all T cell receptors, while the light chain is different for each receptor. The T cell receptor is produced when a gene for the receptor is copied from the DNA of a T cell into a messenger RNA molecule. The RNA molecule is then used to make a protein molecule.
Maturation of T cell
Maturation of T cells begins in the thymus gland. T cells that are produced in the thymus are called thymocytes. Thymocytes undergo a process of selection and maturation as they move through the thymus. Only the cells that are able to respond to the body’s own proteins are allowed to mature. These cells are called self-tolerant cells. The thymocytes that are not able to respond to the body’s own proteins are eliminated.
Positive Selection
Positive selection is a process that favors the proliferation of alleles that contribute to the adaptive fitness of a population. It is the opposite of natural selection, which is a process that favors the proliferation of alleles that lead to the extinction of a population. Positive selection can be caused by a number of factors, including changes in the environment, the introduction of new selective pressures, or the mutation of previously neutral alleles into beneficial alleles.
Negative Selection
Negative selection is a process in which cells with deleterious mutations are eliminated from a population. This occurs because the cells with the mutations are less likely to survive and reproduce than the cells without the mutations.
T- Cell Activation
The activation of a T cell involves the stimulation of its TCR, which causes the cell to undergo a series of biochemical changes. The first change is the activation of the cell’s phosphatases, which removes the phosphate group from many proteins, including the TCR. This allows the TCR to bind to its ligand on the surface of an antigen-presenting cell.
Next, the TCR undergoes a conformational change, which allows it to bind to the peptide fragment of the antigen that is bound to the MHC molecule. This interaction between the TCR and the peptide-MHC molecule causes the TCR to become phosphorylated, and this phosphorylation signals the cell to undergo a series of changes that leads to its activation.
The most important change is the induction of the T cell receptor zeta (TCRz) chain, which is a critical component of the TCR that is not expressed until the T cell is activated. The TCRz chain binds to the Zap70 protein, which is a tyrosine kinase that is involved in the activation of the T cell.
The Zap70 protein then phosphorylates the Syk protein, which is also a tyrosine kinase. The Syk protein then phosphorylates a number of other proteins, including the IkB kinase (IKK) and the mammalian target of rapamycin (mTOR). These proteins then activate the
Types of Effector Cell and Their Function
There are three types of effector cells:
1. Helper cells – Help to activate the immune response by stimulating other cells.
2. Killer cells – Destroy viruses and bacteria to protect the body.
3. Memory cells – Store information about previous infections so the body can respond more quickly the next time an infection occurs.
Downregulation of Effector Cell Function
CD4+ T cells are the main cells of the immune system that recognize and destroy pathogens. They also produce cytokines, which are proteins that help regulate the immune system.
Cytokines are important for the activation and function of T cells. T cells that produce high levels of cytokines are called effector T cells. These T cells are able to recognize and destroy pathogens more effectively.
Cytokine production is regulated by a number of factors, including the activity of regulatory T cells. Regulatory T cells produce cytokines that inhibit the activity of effector T cells.
If the number of regulatory T cells increases, it can lead to a decrease in the number of effector T cells and a decrease in cytokine production. This can lead to a decreased ability to fight infection and disease. Effector Cell – Definition Activation Process Types and Function.
