Expression of MHCII-related genes and the E3 ligase March1 vary in different GC subsets. GC B cells were FACS sorted based on their CXCR4 and MHCII staining profile and subjected to RT-PCR analysis. Data were normalized to Hprt. Points represent individual samples from separate mice, with data pooled from two experiments each with two mice. Horizontal lines indicate means.