Examples of marked changes in gene expression between pre-infection and acute infection in the Wave 2 cohort included components of ‘Immunoregulatory interactions between a lymphoid and a non-lymphoid cell’ pathway term (e.g., SIGLEC1, SIGLEC9, SELL, all increased) and ‘Development and heterogeneity of the ILC family’ (e.g., IFNG, GATA3, RORA, all decreased) (Fig. 2b). This evidence concerns the gene SELL and infection.