One study found gender differences in the inflammatory response of mice to the lung after nickel exposure, with the male being more susceptible to acute pneumonia and subchronic lung inflammation than females by a mechanism that induces increased neutrophil by CXCL1 and IL-6/STAT3 signaling pathways and enhanced monocyte infiltration by CXCL1 and CCL2 in male (41). Here, CXCL1 is linked to pneumonia.