Argumentative essay on Discuss the importance of adhesion molecules in health and disease. Needs to be 6 pages. They participate in the recruitment of neutrophils to the site of inflammation in a dynamic and multiple-step manner. Different families of adhesion molecules participate in leukocytes localization dynamics: selecting family and their ligand participate in the rolling phase. integrin family and their ligands mediates the activation and firm adhesion of leukocytes to the endothelium. both selectins and integrins participate in trans-endothelial migration. Inflammatory and immune responses are important in host defense but on the other hand they can also generate pathological inflammation in a variety of conditions. Several illnesses characterized by acute inflammation with infiltration of neutrophils are in most of the cases associated with augmented expression of selectins (E-selectin and P-selectin), while ICAM-1 and VCAM-1 expression prevails in chronic conditions (Etzioni, 1996). Furthermore, enhanced local expression and increased amount of serum-soluble adhesion molecules have been reported in atherosclerosis, ischemia-perfusion injury, acute lung injury, rheumatoid arthritis and graft/organ rejection (Bevilacqua et al., 1994).
Asthmatic symptoms have been linked to specific cytokines (IL-4 and IL-5) which are produced by CD4 T helper cells. CD4 helper cells are not only the major lymphocyte responders in an allergic response, but also the cells responsible for the memory of an allergen. Very Late Antigen 1 (VLA-1) and VLA-2 are two adhesion molecules (integrins) implicated in the attachment of CD4 T helper cells to the extra-cellular matrix of the lung during allergic asthma. The expression of these adhesion molecules is thought to be of vital importance in the capability of the immune system to react against allergens. Thus, in people without asthma normal adhesion of CD4 T helper cells will help the organism to react against a dangerous antigen, but in asthmatic patients the inhalation of a harmless