Biomarker for diagnosing nonspecific interstitial pneumonia

The principal problem addressed by the present invention is the provision of a biomarker that allows simple, high-precision clinical or histopathological diagnosis of nonspecific interstitial pneumonia. At least one antibody, contained in a blood sample, selected from among a group consisting of an anti-Mx1 antibody, an anti-NINJ2 antibody, an anti-DCX antibody, an anti-C10orf49 antibody, an anti-ZMAT4 antibody, an anti-CDC42SE1 antibody, and an anti-GPT2 antibody can serve as a biomarker for nonspecific interstitial pneumonia (NSIP).