TABLE 2.   Anti-SIV responses of treated and control monkeysa Treatment Animal Absorbance at 405 nm at wk postchallenge No. of antibody-negative animals/total 2 4 8 12 CAP:I 89D420 0.182 0.221 0.169 0.034 3/6 H608 0.171 0.141 0.151 0.035 359L 0.167 0.455 ND ND 407L 0.157 0.156 0.160 0.043 H671 0.170 0.426 ND ND 89D367 0.170 0.304 ND ND CAP:II 89C001 0.168 0.055 0.048 0.039 4/6 P778 0.181 0.089 0.013 0.035 976W 0.188 0.236 1.913 1.486 P851 0.193 0.167 0.377 0.172 936P 0.193 0.035 0.036 0.040 P407 0.158 0.066 0.087 0.053 Control 89D264 0.159 0.371 0.853 0.595 0/4 89D205 0.175 0.466 ND ND 59R 0.156 0.495 1.069 0.347 AH37 0.159 0.452 0.765 0.467 a Results in italics correspond to single treatment and challenge. A whole-virus antigen ELISA was used to evaluate seroconversion to SIV. The historical cutoff for this assay is an optical density of 0.250. ND, not done. Positive responses are indicated in bold.