MARCO and arthritic joint disease: The study revealed that in the draining lymph nodes of late-stage arthritis, close crosstalk between ALCAM+ macrophages and CD6 + T cells promoted B cell differentiation into plasma cells and IgG2b+ class switching.100 The aggregation of IgG2b+ plasma cells near the MARCO+ sinusoids in the draining lymph nodes was associated with the exacerbation of late-stage arthritis.100 The findings of Kenney et al. further deepen our understanding of the relationship between arthritis progression and lymphatic dysfunction.