<prompt> Which leukotriene is the adhesion factor for the neutrophil on the cell surface to attach endothelium?B4C4D4E4  <response>: Ans: A B4 Ref: Ammthanarayan R. Paniker CKJ. Textbook of Microbiology, 8th Edition. Hyderabad: Universities Press: 2009. Pg. 165Explanation:LeukotrienesA substance originally demonstrated in lungs, producing slow, sustained contraction of smooth muscles, and therefore termed slow reacting substance of anaphylaxis SRS-A, has since been identified as a family of leukotrienes LTB4, C4, D4, E4.LTB4 is a potent mediator of leukocyte movement both in vitro and in vivo. It mediates interaction of neutrophils PMNs w ith vascular endothelial cells. 