Monocyte Transmigration

ABSTRACT: We investigated the hypothesis that transmigration drives monocyte transcriptional changes. Using Agilent Whole Human Genome Microarrays, we identified over 600 differentially expressed genes (2x, p<0.05) in freshly isolated human monocytes following 1.5 h of transmigration across IL1beta-stimulated ECs compared to untreated monocytes. Genes up-regulated by monocyte transmigration belong to a number of overrepresented functional groups including immune response, and inhibition of apoptosis. qRT-PCR confirmed increased expression of monocyte chemotactic proteins 1 and 3 and of NLR family apoptosis inhibitory protein (NAIP) following monocyte transmigration. In addition, quantification of annexin V binding revealed a reduction in apoptosis following monocyte transmigration. Comparison of gene expression in transmigrated monocytes to additional controls (monocytes which failed to transmigrate and monocytes incubated beneath stimulated ECs) revealed 89 differentially expressed genes which were controlled by the physical process of diapedesis. Functional annotation of these genes showed down-regulation of antimicrobial genes (e.g. alpha-defensin down 50x, cathelicidin down 9x, and cathepsin G down 3x). qRT-PCR confirmed down-regulation of these genes. Immunoblots confirmed that monocyte transmigration down-regulates alpha-defensin protein expression. Overall, these data indicate that exposure of monocytes to stimulated ECs promotes further monocyte recruitment and inhibits monocyte apoptosis. Unexpectedly, following transmigration monocytes displayed reduced anti-microbial expression.

ORGANISM(S): Homo sapiens

PROVIDER: GSE14027 | GEO | 2009/11/16

SECONDARY ACCESSION(S): PRJNA112453

REPOSITORIES: GEO