Resistance, Remission, and Qualitative Differences in HIV Chemotherapy
Figure 2. Four simulations corresponding to therapy (2). The simulations have a common viral set-point of disease progression with the treatment starting values T(0) = 306/mm3 and Vs(0) = 21/mm3 (obtained from Figure 1a,b at 5.8 years), T(0) = 217/mm3 and Vs(0) = 31/mm3 (obtained from Figure 1a,b at 7.7 years), T(0) = 100/mm3 and Vs(0) = 69/mm3 (obtained from Figure 1a,b at 8.4 years), and T(0) = 43/mm3 and Vs(0) = 156/mm3 (obtained from Figure 1a,b at 8.6 years). The rates of exponential increase in (approximately .03, .02, .01, .005) are inversely correlated to starting CD4+ T-cell counts, and the exponential rates of decay in (all about -.2) are not correlated to starting viral levels (different viral set-points would give different values for the parallel slopes) (1,2). The lack of correlation of viral decay rates is an indication of slower clearance of wild-type virus in the external lymphoid compartment. The time to the downward spike in is correlated to starting viral levels (1). The treatment parameters c1=2.0, c2=.17, c3=.15 and the resistance mutation parameter q=10-6 are the same in all four simulations.