ABSTRACT The present invention relates to particularly stable and soluble scFv antibodies and Fab fragments specific for TNF, which comprise specific light chain and heavy chian sequences that are optimized for stability, solubility, in vitro and in vivo binding of TNF, and low immunogenicity. Said antibodies are designed for the diagnosis and/or treatment of TNF mediated disorders. The nucleic acids, vectors and host cells for expression of the recombinant antibodies of the invention, methods for isolating them and the use of said antibodies in medicine are also disclosed.