In vitro, incubation of bone marrow cells from wildtype mice with recombinant IL-1β resulted in a significant increase in neutrophil CXCR2 (Figure 5B), whereas neutralizing IL-1β with anti-IL-1β antibody in CDI-plasma reduced the increase in neutrophil CXCR2 (Figure 5C). The gene discussed is CXCR2; the disease is clostridium difficile infection.