Recurrent Group A Streptococcus Tonsillitis

To determine differences in GC Tfh cells isolated from the tonsils of children who have undergone tonsillectomy for either recurrent Group A Streptococcus (GAS) tonsillitis (RT) or non-RT (sleep apnea). Grants: Thrasher Research Fund for an Early Career Award 12969 - Jennifer Dan UM1 AI100663 - Shane Crotty Clinical Research Fellowship Grant UK Charity No. 1089464 - David Layfield, Ramsey Cuttress, Christian Ottensmeier Overall design: Tonsillar cells were isolated from 5 RT and 5 non-RT children. Cells were left unstimulated or stimulated with GAS or recombinant streptococcal pyrogenic exotoxin A (SpeA), a critical GAS virulence factor. Cells cultured for 18 hours. Cells were sorted for GC Tfh cells (CXCR5hiPD-1hiof CD45RA-CD4+T cells) using the Activation Induced Marker (AIM) assay. For unstimulated cells, CD25-OX40-GC Tfh cells were sorted. For GAS-specific or SpeA-responsive GC Tfh cells, CD25+OX40+GC Tfh cells were sorted. All cells were sorted into RNA lysis buffer. All data are derived from GC Tfh cells.