Functional Characterization of Antibodies against Neisseria gonorrhoeae Opacity Protein Loops
Figure 2
Specificity of antibodies against the conserved Opa loops.
Cell lysates of an Opa-negative variant and each of the 8 Opa–positive variants of strain FA1090 were incubated at RT or 100°C prior to fractionation and incubated with (A and D) AbSV linear (1∶75,000), (B and E) AbSV cyclic (1∶6,000), and (C) Ab4L linear (1∶6,000). The broader reactivity of AbSV cyclic compared to AbSV linear is clearly shown whether native or denatured Opa proteins are analyzed. Ab4L linear is even more broadly reactive in that it recognizes all denatured Opa proteins well except OpaE. None of the antibodies recognize a protein in the Opa-negative lane (−). The location of a 25 kDa molecular weight marker is indicated, and the denatured Opa proteins migrated at a slightly higher molecular weight than those incubated at RT, which is consistent with well characterized heat modifiable nature of these proteins. The Ab4L linear immunoblot was kindly provided by Dr. Amy Simms.