RT Journal Article SR Electronic T1 Recent thymic emigrants produce antimicrobial IL-8, express complement receptors and are precursors of a tissue-homing Th8 lineage of memory cells JF bioRxiv FD Cold Spring Harbor Laboratory SP 059535 DO 10.1101/059535 A1 Marcin L Pekalski A1 Arcadio Rubio García A1 Ricardo C Ferreira A1 Daniel B Rainbow A1 Deborah J Smyth A1 Meghavi Mashar A1 Jane Brady A1 Natalia Savinykh A1 Xaquin Castro Dopico A1 Sumiyya Mahmood A1 Simon Duley A1 Helen E Stevens A1 Neil M Walker A1 Antony J Cutler A1 Frank Waldron-Lynch A1 David B Dunger A1 Claire Shannon-Lowe A1 Alasdair J Coles A1 Joanne L Jones A1 Chris Wallace A1 John A Todd A1 Linda S Wicker YR 2016 UL http://biorxiv.org/content/early/2016/12/12/059535.abstract AB The adaptive immune system utilizes multiple mechanisms linked to innate immune cell functions to respond appropriately to pathogens and commensals. Here we discover further aspects of this connectivity by demonstrating that naïve T cells as they emerge from the thymus (recent thymic emigrants, RTEs) express complement receptors (CR1 and CR2), the bacterial pathogen recognition receptor TLR1 and an enzyme that deactivates bacterial lipopolysaccharide (AOAH) and following activation secrete the anti-microbial cytokine IL-8. CR2+ naïve T cells also express a selection of genes associated with tissue migration, consistent with the hypothesis that following emigration from the thymus RTEs seed peripheral compartments where some pursue their anti-microbial potential by becoming IL-8-producing CR2+ memory cells while others undergo homeostatic expansion. CR2+ naïve and memory cells are abundant in children but decrease with age, coinciding with the involution of the thymus. The ability of CR2, which is also a receptor for Epstein-Barr Virus (EBV), to identify recent thymic emigrants will facilitate assessment of thymic function during aging and aid investigations of multiple clinical areas including the occurrence of T cell lymphomas caused by EBV.