Anti-TNF antibodies, fragments and regions thereof which are specific for human tumor necrosis factor-.alpha. (TNF.alpha.) and are useful in vivo diagnosis and therapy of a number of TNF.alpha.-mediated pathologies and conditions, as well as polynucleotides coding for murine and chimeric antibodies, methods of producing the antibody, methods of use of the anti-TNF antibody, or fragment, region or derivative thereof, in immunoassays and immunotherapeutic approaches are provided.