ITGA4 and infection: Since immunophenotyping of CD11b+ infiltrates revealed a significant difference in neutrophil accumulation in the infection site, we assessed the phenotype of the accumulated neutrophils by examining the expression of adherence molecules, including L-selecting (CD62L), α4-integrin (CD49d), and β2-integrin (CD11c), which are expressed differentially on their surface under inflammatory conditions and are associated with neutrophil recruitment from the circulation (23, –, 25).