Method of producing an immunoligand/payload conjugate

A method of treating a pathologic condition in a subject in need thereof, comprising

• administering to the subject in need thereof an effective amount of an immunoligand/payload conjugate,
• wherein the immunoligand/payload conjugate is produced by enzymatically conjugating at least one glycine-modified payload to the immunoligand with a sequence-specific sortase or a catalytic domain thereof,
• wherein the immunoligand is selected from the group consisting of,
• (i) an antibody,
• (ii) an antibody-based binding protein being a protein containing at least one antibody-derived VH, VL, or CH immunoglobulin domain,
• (iii) an antibody fragment binding to a receptor, antigen, growth factor, cytokine and/or hormone, and
• (iv) an antibody mimetic selected from the group consisting of DARPins, C-type lectins, A-domain proteins of S. aureus, transferrins, lipocalins, 10th type III domains of fibronectin, Kunitz domain protease inhibitors, affilins, gamma crystallin derived binders, cysteine knots or knottins, thioredoxin A scaffold based binders, nucleic acid aptamers, artificial antibodies produced by molecular imprinting of polymers, and stradobodies, and
• wherein the payload is selected from the group consisting of a cytokine, a radioactive agent, an anti-inflammatory drug, a toxin, and a chemotherapeutic agent.