EIF2AK3 and viral myocarditis: Since there is more PERK activation and higher cardiac inflammatory cytokines IL-6 and IL-1β in the hearts of wild-type Trim29fl/fl mice, we investigated whether enhanced PERK, IL-6 and IL-1β mediated more recruitment and activation of MDSC in Trim29fl/fl mice during viral myocarditis by flow cytometry.