CCL4 and susceptibility to pneumonia measurement: Further underscoring the importance of Dusp1 in innate immunity, studies involving pneumonia mouse models infected with Chlamydophila pneumoniae reveal that Dusp1-/-mice elicit a heightened pro-inflammatory response, marked by an increase in cytokines (IL-6 and IL-1β) and chemokines (CCL3, CCL4, CXCL1, CXCL2) 40, contirbuting to abnormal pulmonary leukocyte infiltration.