Blocked lectins; methods and affinity support for making the same using affinity ligands; and method of killing selected cell populations having reduced non-selective cytotoxicity

摘要

An activated affinity ligand is described comprising: a ligand having (a) a region with affinity for binding sites of a lectin; and (b) a reactive group capable of covalently linking the ligand to the lectin to thereby block one or more of the binding sites of the lectin. A blocked lectin is described comprising one or more affinity ligands covalently linked by means of a reactive group present on each of the ligands to a lectin such that one or more binding sites of the lectin is blocked. A cell-binding agent-blocked lectin conjugate is described comprising the above-described blocked lectin and a cell-binding agent covalently linked to: (a) one of the covalently linked affinity ligands; or (b) the lectin. A method of preparing the cell-binding agent-blocked lectin conjugate is described. An affinity support capable of binding to a lectin to form a blocked lectin is described comprising an activated affinity ligand covalently linked to a solid support. A method of preparing the affinity support capable of binding to a lectin to form a blocked lectin is described. A method of killing selected cell populations having reduced cytotoxicity to non-selected cell populations is described comprising contacting a cell population or tissue suspected of containing cells from said selected cell population with the above-described cell-binding agent-blocked lectin conjugate, wherein the lectin is a cytotoxic lectin. Medicaments and methods of treatment using the above-described cell-binding agent-blocked lectin conjugate also are described.