Editorial

Austin J Biotechnol Bioeng. 2014;1(3): 3.

Chemokines: The Holy Messengers of Leukocyte Trafficking

Krishna Mohan Poluri*

Department of Biotechnology, Indian Institute of Technology Roorkee, India

*Corresponding author: Krishna Mohan Poluri, Department of Biotechnology, Indian Institute of Technology Roorkee (IIT-Roorkee), Roorkee-247667, Uttarakhand, India.

Received: September 02, 2014; Accepted: September 04, 2014; Published: September 06, 2014

The classical panorama of an innate immune regulation during inflammation, infection, and sterile tissue injury is the rapid recruitment of circulating leukocytes throughout the organism in an effort to eliminate the infectious pathogens (such as bacteria, virus), tissue damage and other physiological insults. The salient features that are involved in the leukocyte trafficking (Figure 1) are: (a) Release of chemokines - small proteins of size 8-10 kD and are known as chemotactic cytokines, by the tissue macrophages; (b) transcytosis and decoration of chemokines on the luminal surface of endothelium forming the chemokine gradients; (c) the initial attachment and rolling of leukocytes on the inflamed endothelium; during this stage, several adhesion events are arbitrated by the different ligands and receptor pairs. For instance, L-selectin constitutively expressed by leukocytes and P, E-selectins expressed by activated endothelial cells facilitate the initial attachment and rolling of leukocytes on the endothelial surface under shear flow of blood. (d) Activation of the seven transmembrane-spanning G protein- coupled receptors (GPCRs) on the leukocytes by the chemokines bound to proteoglycans/glycosaminoglycans (GAGs) on the luminal surface of the endothelium, resulting in integrin activation and firm adhesion of rolling cells. (e) Migration of the leukocytes along the chemokine gradients, shape change, extravasations across the endothelium, and their entry into the underlying target tissue. (f) Finally, leukocytes perform the immune surveillance activities such as microbial killing and tissue repair through various mechanisms that include phagocytosis, degranulation, and extracellular traps etc [1-6]. From various stages of the recruitment process, it is obvious that chemokines emerge as "master regulators" in mediating the leukocyte trafficking in resolving infection/inflammation.

Citation: Poluri KM. Chemokines: The Holy Messengers of Leukocyte Trafficking. Austin J Biotechnol Bioeng. 2014;1(3): 3. ISSN: 2378-3036