The invention provides antibodies that are modified to reduce aggregration propensity, and methods of producing such antibodies. The present invention also provides particularly stable and soluble scFv antibodies and Fab fragments specific for TNF, which comprise specific light chain and heavy chain sequences that are optimized for stability, solubility, in vitro and in vivo binding of TNF, and low immunogenicity. 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.