Abstract: The present invention relates to polypeptides that are capable of binding to a specific epitope on the neonatal Fc receptor (FcRn). In particular, the present invention relates to novel and improved polypeptides comprising immunoglobulin single variable domains (ISVDs), such as heavy-chain single variable domains, that are capable of binding to a specific epitope on FcRn. The invention further relates to constructs, compounds, molecules or chemical entities that comprise at least one of these ISVDs binding to a specific epitope on FcRn. The present invention further relates to methods for producing such polypeptides as well as to uses of such polypeptides for diverse applications, including but not limited to the extension of the half-life in vivo of therapeutic compounds and/or the prevention and/or treatment of a disease and/or disorder, such as but not limited to a proliferative disease, an inflammatory disease, an infectious disease or an autoimmune disease.

Abstract: The present technology relates to a polypeptide comprising at least three immunoglobulin single variable domains (ISVDs). In particular, the present technology relates to a polypeptide comprising an optimized ISVD binding to fractalkine receptor CX3CR1 and an optimized ISVD binding to albumin. The present technology also relates to a composition of a polypeptide; a polynucleotide encoding a polypeptide; a host or host cell comprising a polynucleotide; a method for producing a polypeptide or composition; and a polypeptide, polynucleotide or composition for use in prevention, therapy and diagnosis of a disease or disorder.

Abstract: The present technology provides immunoglobulin single variable domains (ISVDs) binding both the constant domain of a human T cell receptor (TCR) on a T cell and the constant domain of a non-human primate TCR on a T cell. It also relates to polypeptides comprising an ISVD according to the present technology and at least one ISVD capable of binding to an antigen on a target cell. The present technology further provides nucleic acids encoding said ISVDs or polypeptides as well as vectors, hosts and methods to produce these ISVDs or polypeptides. Moreover, the present technology relates to methods for treatment making use of the ISVDs or polypeptides of the present technology.

Abstract: The present technology provides T cell recruiting polypeptides that specifically bind to the constant domain of a human and of a non-human primate TCR. The present technology also provides nucleic acids, vectors, and compositions. The polypeptides can be used in methods for treatment of cancer.