in ▁back bone ▁has ▁a ▁flu ores cent ▁label ▁to ▁allow ▁flow ▁c yt ometry ▁analysis . ▁Inc ub ation ▁of ▁M HC - St rep - tag ▁fusion ▁prote ins ▁with ▁the ▁St rep - T act in ▁back bone ▁results ▁in ▁the ▁formation ▁of ▁a ▁M HC - mult imer , ▁which ▁is ▁capable ▁for ▁ant igen - specific ▁st aining ▁of ▁T ▁cells . ▁ ▁Re vers ible ▁st aining ▁Because ▁the ▁mole c ule ▁d - bi ot in ▁has ▁a ▁much ▁higher ▁aff inity ▁to ▁St rep - T act in ▁than ▁St rep - tag , ▁it ▁can ▁effectively ▁comp ete ▁for ▁the ▁binding ▁site . ▁Therefore , ▁a ▁M HC ▁mult imer ▁based ▁on ▁the ▁interaction ▁of ▁St rep - tag ▁with ▁St rep - T act in ▁is ▁easily ▁dis rupted ▁in ▁the ▁presence ▁of ▁relatively ▁low ▁concentr ations ▁of ▁d - bi ot in . ▁Without ▁the ▁St rep - T act in ▁back bone , ▁the ▁single ▁M HC - St rep - tag ▁fusion ▁prote ins ▁sp ont ane ously ▁det ach ▁from ▁the ▁T CR ▁of ▁the ▁T ▁cell , ▁because ▁of ▁weak ▁binding ▁aff in ities ▁( mon omer ic ▁M HC - ep ito pe ▁complex es ▁cannot ▁provide ▁stable ▁binding , ▁see ▁above ). ▁ ▁References ▁ ▁Category : Pro te in ▁methods ▁Category : Bi ote chn ology ▁Category : M ole cular ▁bi ology ▁techniques ▁Category : B io chem istry ▁Category : L abor atory