The present invention is directed to an isolated nucleic acid molecule encoding an interferon-.alpha.-induced protein, particularly the protein designated p36. Expression vectors and host cells comprising the nucleic acid molecule are also provided, as well as methods for increasing or decreasing the expression of the interferon-.alpha.-induced protein in host cells. DNA oligomers and antibodies specific for interferon-.alpha.-induced protein are provided, each of which can be used to detect interferon-.alpha.-induced protein in a sample. Methods for diagnosing immunodeficiency and autoimmune disease in an individual and methods for detecting the presence or past existence of lupus inclusions or interferon-.alpha. in a sample are also provided.