Differences between Cytokines and Chemokines
The body is meekly and specially designed to regulate its process by different mechanisms. The leukocytes are charged with the function of combatting infection and mounting self-defense mechanism against pathogens and any foreign bodies. Other homeostatic processes critical to maintaining body functions are thermoregulation, excretion, and maintenance of electrolyte balance. The body is prone to infection both from the normal flora and extrinsic pathogen. There are five classes of white blood cells which act by different mechanisms to exert an immune response. The immunity type can either be innate or adaptive, and leucocytes through the facilitation of cytokines are especially vital in the immune response. Growth factors are also involved in synchronizing immunity.
Inflammation usually an immune response characterized by pain, redness, and heat is a vital sign of infection and effective action of the immune system; it is evident in both innate and adaptive immunity and is often mediated by cytokines. Cytokines are small proteins (5-20Kda) released by different cell and are crucial in cell signaling. They are inflammatory molecules and are categorized as pro-inflammatory or anti-inflammatory cytokines. They can act autocrine, paracrine or endocrine and there exists a thin and usually misunderstood distinction between them and hormones.
Cytokines are released by a broad range of specialized cells which include; macrophages, T-lymphocytes, mast cells, endothelial cells among others. They are usually pleiotropic in nature and can act synergistically or antagonistically on the same cell. After production, they bind to specific receptors and initiate a cascade of immune reactions. Notable triggers to cytokine release include pathogens, foreign bodies, and autoimmune factors. The most conspicuous manifestation of cytokine-receptor complex response is inflammation.
There are different subclasses of cytokines depending on their mode of action and target cell receptors, these include; adipokines, chemokines, interferons, interleukins and lymphokines.
Chemokines are low molecular weight particles which are chemotactic immune components. They are a subclass of cytokines and consist of diverse types of protein molecules that act to initiate an immune response seen as inflammation and also regulate other cell functions for instance growth and maturation of cell populations. Their ultimate role is to activate leucocytes and facilitate migration towards the target cells. Chemokines bind to G-protein coupled receptors and initiate a cascade of immune reaction commencing by activation of GTPase thus preparing the cells for movement to the offended sites.
Chemokines induce chemotaxis to nearby cells that have immune properties. They have specific cysteine residue, and this is vital in their classification into the four groups. Considering functionality, chemokines are classified as either inflammatory chemokines or homeostatic chemokines. The homeostatic type is involved in cell migration during maintenance or tissue development.
Similarities between cytokines and chemokines
Being a subclass of cytokines, chemokines share some properties with cytokines. Structural similarity is the most notable since both are protein biomolecules. Functional similarities are also evident, and both chemokines and cytokines are markers of inflammation and do this by binding to a specific protein receptor on the surface of injured cells or tissues. Also, the two can initiate a cascade of reaction as an immune response
Difference between cytokines and chemokines.
As molecules of the same origin serving nearly similar functions, it may be confusing creating a distinction between cytokines and chemokines. Crucial differences that will help you distinguish the two are elaborated below;
Cytokines vs. chemokines
Cytokines are cell signaling molecules that are produced by different cell types for specific biological functions mainly immune response. For instance, interferon is a type of cytokine produced by white cells in response to the invading virus and other foreign organisms. On the other hand, Chemokine is a type of cytokine that is presented as a Chemo-attractant agent; to attract cells especially leucocytes to sites of infection/inflammation.
Many cytokines general have structural similarities even though slight variations exist and act as a distinguishing factor. Cytokines have a conserved cysteine residue, this is present in interferons, interleukins, and adipokines. In contrast, for chemokines conserved cysteine residues are absent. The presence of cysteine residues is critical in determining the functions of cytokines. The absence of cysteine residue in chemokines is speculated to be responsible for its mobility properties hence chemotaxis.
The cytokine is a broad class of small proteins molecules with are subgrouped as chemokines, interleukins, interferons, and adipokines. The criteria used in subdividing cytokines is the type of target receptor interaction in each case. Chemokines as a category of cytokine are further divided into four classes depending on the characteristic in conserved cysteine residues. The levels include; CXC chemokine, C chemokines (lymphotactin), CXXXC chemokines (fractalkine) and CC chemokines all charged with vast immune functions.
The functional difference between cytokines and chemokines
Cytokines are involved in both the cellular immunity and antibody-mediated immunity as the modulating agents can act at site or afar. Cytokines are capable of acting on many cell types while chemokines are limited to leucocytes and lymphocytes thus they are most useful in guiding of cells in the immune system to the site of infection.
Considering action and resultant effects, cytokines can either be pro-inflammatory or anti-inflammatory whereas chemokines are generally inflammatory or homeostatic creating a balance and maintaining body parameters and functions in spite of deviations caused by foreign bodies.
The principle differentiating factor between cytokines and chemokines is in their functions during the initiation and mediation of immune response. Cytokines exhibit considerable structural similarities across the board. They only differ in their roles during immunity, and a close monitor of this will be indispensable in identifying one from the other.
Cytokines are primarily involved in the cellular immunity as well as antibody-mediated immunity during inflammation by inducing non-specific immune responses against pathogens. Cytokines act similarly as hormones as they both bind to specific receptors leading to a cascade of reaction thus the ability to differentiate the two is also crucial. A clear understanding of body immune components at the cellular and molecular level is vital for research purposes as creation and modeling of analogs have proven to be of significance in the treatment of various infections.