Figure 4.

Ocular B cells are activated B cells with transcriptional similarities to synovial B cells in rheumatoid arthritis (RA). Clonally expanded B cells demonstrate evidence of plasmablast differentiation and class switching. A, Diagram showing t-distributed stochastic neighbor embedding subanalysis of blood and ocular B cells colored by cluster (top panel) or by tissue source (bottom panel). B–E, Clusters B8 and B9 were excluded from further analysis because these clusters represented predominantly myeloid cells and erythrocyte precursors, respectively. B, Heatmap representation of relative gene expression of cluster-defining genes (rows) for each patient (columns black, red, grey, blue) and tissue (blood, red; eye, grey). Clusters are annotated with cell lineages defined above. Genes specific to B-cell subsets and T cells are indicated with labeled brackets. Samples with less than 5% contribution to each cluster were excluded. C, Heatmap representation of relative expression of cell lineage or state-defining gene set expression between B-cell clusters. Samples with less than 5% contribution to each cluster were excluded. D, Diagram showing distribution of the top expanded B-cell clonotype from patient UV150 between activated B cell (ABC; B4 and B6) and plasmablast (B7) clusters. E, Concentration of each immunoglobulin subclass in blood, ocular ABCs, and ocular plasmablasts clusters for each patient. Relative frequency of switched non-immunoglobulin M (IgM) subclass increases with differentiation. F, Relative expression of AICDA, found primarily in ABCs. PB = plasmablast.