I am afraid your question is far too abridged. You need to tell us what you are planning to do and what type of cells you are after. When you say sensitised, sensitised to what? Are you after antibody coated cells? Please provide more information, we will try to guide you. Best wishes.
Does this answer your question? https://www.sigmaaldrich.com/life-science/metabolomics/enzyme-explorer/cell-signaling-enzymes/complement-proteins/preparation-of-antibody.html