CD80 and gonorrhea: However, there was no significant difference in the expression of the costimulatory molecule CD80 on the surface of dendritic cells when exposed to the microparticulate formulations of n-butyl—DPD, isobutyl—DPD, n-hexyl—DPD, and phenyl—DPD in combination with the microparticulate gonorrhea vaccine compared to the cells exposed to the gonorrhea vaccine microparticles alone (Figure 16B).