CD4 and infection: Lymphocyte-activation gene 3 (LAG3) expressed exclusively in activated T and NK lymphocytes, was upregulated only in MN, is a CD4 homologue that binds MHC class II molecules with very high affinity and has a negative regulatory effect on T cell function and DC maturation (Fig. 4(C)).41, 42 Analysis of the expression of transcription factors in MN indicated that IRF1, STAT1 and STAT2 were the most highly expressed transcription factors activated in similar proportions in both groups, whereas, E2F1, PLM and KLF5 were the transcription factors changing the most after infection.