2020 Pediatric Rheumatology Research in Review

Staying with the theme of big data as it relates to lupus, Dr. Schulert discussed a study by Nehar-Belaid et al. examining molecular heterogeneity in pediatric lupus by mapping expression of genes from lupus-related monogenic disorders to distinct cell clusters, including mostly monocytes and dendritic cells. The researchers found that combining cell cluster enrichment yielded six patient cellular clusters, which provides a “tremendous resource for lupus immunology to lay the groundwork for understanding the heterogeneity of pediatric lupus,” he said.¹⁸

Another interesting cell population with relevance to pediatric rheumatic diseases are PRIME cells, Dr. Schulert noted. In recent research using PRIME cells to predict rheumatoid arthritis flares, he discussed a paper by Orange et al. that used a unique method of obtaining three drops of blood once per week remotely from study patients, paired with a weekly remote clinical assessment, to identify the unique gene expression characteristics of patients experiencing a flare, characterized by circulating PRIME cells.¹⁹ Dr. Schulert said this approach raises an interesting question regarding the identification of similar PRIME cells in childhood arthritis.

Shifting gears back to pediatric rheumatology and the genetics of PFAPA, Dr. Schulert shared findings from a study by Manthiram et al. that looked at common genetic susceptibility loci links between PFAPA syndrome, Behçet’s disease and recurrent aphthous stomatitis.²⁰ The investigators examined three large cohorts of PFAPA patients using a target gene approach to identify genetic risk alleles and found both Behçet’s and PFAPA most significantly associate with interleukin 12α, especially during PFAPA flares.

In a separate study looking at autoinflammation, de Jesus et al. measured distinct interferon signatures and cytokine patterns to define additional systemic autoinflammatory diseases among four distinct groups of patients and found that the interferon-stimulated gene score can be used to identify and subdivide patients with undifferentiated systemic autoinflammatory diseases, Dr. Schulert explained.²¹

Carina Stanton is a freelance science journalist based in Denver.

References

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