SMCC (Succinimidyl-4-(N-maleimidomethyl cyclohexane)-1-carboxylate) is a hetero-bifunctional crosslinker that contain N-hydroxysuccinimide (NHS) ester and maleimide groups that allow covalent conjugation of amine- and sulfhydryl-containing molecules. SMCC-conjugated antigen couples spleen cells to induce antigen-specific immune responses.