Given the mechanism of action, the ideal antibody needs to have sufficient antigen affinity and specificity.
As a result engineering is carried out at finer sequence resolution relative to standard CDR grafting methods, providing for the optimization of antibody properties beyond immunogenicity such as antigen affinity and solution behavior.
huHMFG1 was shown to retain the antigen affinity and same specificity of the rodent ancestor.
Several mutations yield amino acid substitutions that improve antigen binding by increasing the antigen affinity and diversity [ 12].
The relative importance of these factors (antigen density, antigen affinity and internalisation) in the killing process has not yet been determined.
Clearly, many factors including antigen affinity and antigen density will also play an important role in the killing of targeted antigen-positive cells, since those with high density will attract more AIC and those with higher antigen affinity may 'hold on' to increased levels of radioactivity for a longer time period.
Variable regions derived from such techniques can readily be grafted onto antibody framework constructs to generate repertoires of full-length antibodies of the desired isotype, and screened for properties including antigen affinity and specificity.
Even though the underlying protein scaffold remains constant in a heterogeneous population of ADCs, each conjugate has its own set of properties with respect to important parameters such as pharmacokinetics, toxicity, aggregation, antigen affinity, and drug release.
In lymphocyte signaling, T- and B-cells' cell fate depends on both antigen quality (affinity) and quantity (amount of presented antigen).
However, the degenerate primer mixtures commonly used for PCR cloning of antibody fragments can and frequently do introduce out-of-context mutations to combinations that can lead to severe reduction of stability, production yield and antigen affinity.
