CCL2 and infection: Protection from heterologous SARS-CoV-2 Omicron EG.5.1.1 infection was also reflected by reduced systemic CXCL10, CXCL11 and CCL2 inflammatory cytokine production in Ad5 (purple symbols), and Delta (orange symbols) animals relative to the control animals, while CXCL9 was rather sporadically induced in single animals independent of the treatment (Fig. 7a–d).