Abstract: An analogue peptide that comprises the variable regions of the light or heavy chains of an antibody of a first species selectively binding to a carcinoma antigen has 1 to 46 amino acids of the framework regions per chain substituted with amino acids such as those present in equivalent positions in antibodies of a species other than the first species, or fragments thereof comprising 1 to 3 variable region CDRs per chain and optionally flanking regions thereof of 1 to 10 or more amino acids, alone or with an N-terminal fragment of 1 to 10 or more amino acids, combinations or mixtures thereof. The polypeptide may also comprise an effector agent and/or be glycosylated, and is presented as a composition with a carrier. The analogue peptides are used in diagnostic kits for carcinomas and methods for in vivo imaging and treating a primary or metastasized carcinoma, and in vitro diagnosing a carcinoma, ex vivo purging neoplastic cells from a biological fluid.

Abstract: The present invention provides recombinant peptides that specifically and selectively bind to the human milk fat globule (HMFG) antigen, BA46. In particular, the present invention provides recombinant variants of the Mc3 antibody, including humanized versions of Mc3. The variant Mc3 peptides are particularly useful for diagnostic, prognostic, and therapeutic applications in the field of breast cancer. The present invention also provides methods for the humanization of antibodies such as murine monoclonal antibodies. The novel humanization methods are applied to the production of humanized Mc3 antibodies and it is shown that these humanized antibodies retain the ability to engage in high affinity binding to their cognate antigen. Such humanization enables the use of these antibodies for immunodiagnostic and immunotherapeutic applications in humans.