Figure 4.

Variable B-cell homeostasis in human SLE. The challenge of tailoring specific B-cell therapies for a heterogeneous B-cell disease is illustrated by the high variability of B-cell profiles displayed by individual SLE patients. This variability applies to both populations with regulatory potential (transitional and marginal zone-like cells) and pathogenic potential (memory, effector and plasma cells). This figure represents a heat map showing B-cell profiles for normal individuals and patients with SLE. Each column represents an individual and each row corresponds to a B-cell subset (specified on the right according to previously published classifications). Both individuals and cell populations are hierarchically clustered and reordered accordingly. Color maps correspond to the log of the percentage of the cell subset with respect to the CD19⁺ subset (except for the 9G4⁺ group, which are expressed relative to their immediate parent population). The healthy and SLE groups were clustered separately, each using correlation as the distance measure and complete linkage. There were 25 healthy individuals and 49 patients with SLE. This type of data visualization clearly demonstrates both high interindividual variability as well as clustering of patient subsets, and should help design and evaluate B-cell therapies in SLE. Abbreviations: CXCR, CXC-chemokine receptor; SLE, systemic lupus erythematosus.