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CONDITION : B = ACTIVE OR B = PRESENTING-2
ACTION : B → INTERNALISED AND Ag → deleted
In each site of the lattice, the procedure may fi nd a couple
of elements in the two sets of B-cells and antigens for which
the conditions are fulfi lled. In this case the conditions are: the
B-cell has to be active or presenting the epitope and the match
is between its receptor and the antigen epitope. If more epitopes
defi ne the antigen, then all of them are tested; the set of epitopes
is scanned in random order to avoid bias. Given the BCR and the
Ag’s epitope, the match and the affi nity are computed in terms
of probability to bind, utilising the affi nity function as defi ned
in section 3.5. Then a coin with that probability is fl ipped and the
decision of ...