The disclosure also relates to a method of reducing the number of neutrophils in a body region by administering a Serum Amyloid P (SAP) composition in an amount and for a time sufficient to suppress neutrophil movement into the body region. In particular, it relates to a method of reducing the number of neutrophils in a body region suffering from an acute injury or from a chronic or long-term disease. Further, the disclosure relates to a method of increasing the number of neutrophils in a body region by administering an anti-SAP antibody or material able to bind SAP. The disclosure further relates to compositions usable with these methods.