On the Cover: Effect of adjuvant in germinal centers development. Spleens from A, WT and B, Cr2^-/- mice collected 10 days after immunization with NP-KLH in PBS. Spleens from C, WT and D, Cr2^-/- mice collected 10 days after immunization with NP-KLH precipitated in alum. Mesenteric lymph nodes from E, WT and F, Cr2^-/- mice collected 10 days after immunization with NP-KLH precipitated in alum. Germinal centers and follicles were visualized by staining with PNA (blue) and anti-IgD (brown) Ab, respectively. (Figure 4 from X. Wu, N. Jiang, Y.-F. Fang, C. Xu, D. Mao, J. Singh, Y.-X. Fu, and H. Molina. Impaired affinity maturation in Cr2^-/- mice is rescued by adjuvants without improvement in germinal center development. J. Immunol. 165:3119.)