What are Cytokines?
Cytokines are small cell-signaling protein molecules, which are used extensively in intercellular communication. Cytokines can be classified as proteins, peptides, or glycoproteins. The term cytokines refer to a large and diverse family of regulators produced throughout the body by cells of diverse embryological origin.
Cytokines are a unique family of growth factors. They are secreted primarily from leukocytes and can be produced by a variety of hematopoietic and non-hematopoietic cell types and exert autocrine, paracrine and endocrine effects, as do the hormones. They are, therefore, more correctly related to hormones than to growth factors in their overall functions. Cytokines stimulate both humoral and cellular immune responses, as well as the activation of phagocytic cells.
What are Growth Factors?
Growth factors are proteins that bind to receptors on the cell surface, with the primary result of activating cellular proliferation and/or differentiation. Many growth factors are quite versatile, stimulating cellular division in numerous different cell types; while others are specific to a particular cell-type. Growth factors are capable of stimulating cellular growth, proliferation and cellular differentiation.
Growth Factors and Cytokines in Wound Healing
Growth factors, cytokines and chemokines are crucial for coordinating multiple cell types during the healing process. Proper wound healing is guided by stringent regulation of these agents as well as a wound environment that favors their activity. As to the acute wound, the healing process is controlled by spatio-temporal action of these growth factors. Cytokines and chemokines will lead through progression of healing, resulting in the re-establishment of the skin’s barrier function. What’s more, the generation of a proteolytic environment by inflammatory cells infiltrating the wound site and the prolonged up-regulation of pro-inflammatory cytokines and chemokines will inhibit normal progression of wound healing.
Growth factors and cytokines released at sites of injury and inflammation play an important role in stimulating endothelial progenitor cell (EPC) migration to these sites. The comparative analysis of literature shows that under neutral in vitro conditions, several growth factors and cytokines influence favorably indices of EPC angiogenic function. While, under acidic conditions, the biological activity of certain growth factors may be impaired, although TPO, SCF and IL-3 were each able to rescue EPCs from acidic exposure apoptosis, a combination of these three factors stimulated cell proliferation and prevented apoptosis. Possible combinations of growth factors and cytokines together with EPC transplantation may provide for a greater extent of vessel repair and new vessel formation.
Creative Bioarray develops and offers Cytokines & Growth Factors for studies in many areas of biological research including cancer, angiogenesis and other research purposes.