Predicted to enable serine-type endopeptidase inhibitor activity. Predicted to be involved in antibacterial humoral response and innate immune response. Predicted to act upstream of or within negative regulation of peptidase activity. Predicted to be located in extracellular region. Predicted to be active in extracellular space. Is expressed in brain; epididymis; and lung. Orthologous to human WFDC3 (WAP four-disulfide core domain 3). [provided by Alliance of Genome Resources, Apr 2022]