Information Technology Reference
In-Depth Information
Therefore, adaptation to antibody surveillance under these simulation conditions re-
duced the functional component of fitness by 40%. Also note that a narrower antibody
response (higher stimulation threshold) increased the duration of high V3 function.
Figure 6 shows V3 sequences from one replicate simulation after 500 generations
with an antibody production stimulation frequency threshold of 0.1. Amino acid
replacements, mainly at two sites, produced sequences that are neutralization resis-
tant but suboptimal with regard to their interaction with CCR5.
9.4.3.2 Effect of the Strength of Coreceptor Selection
The effect of the strength of selection by the chemokine coreceptor was investigated
by rerunning simulations with different coreceptor selection coefficient scaling fac-
tors (Fig.7). These simulations were run with an antibody production stimulation
frequency threshold of 0.1 and should be compared with the corresponding plot in
Fig. 5. A coreceptor selection coefficient scaling factor of 0.1, instead of 0.25, as was
used previously (Fig. 5), did not alter appreciably the dynamics of the neutralization
Fig. 6.
Twenty randomly chosen V3 sequences from one replicate simulation with an antibody
production stimulation threshold of 0.1. Other parameter values are as described in Fig. 5.
Periods indicate identity with the initial sequence.
