Primate Monocytes - CD14, CD16 - Ziegler-Heitbrock

What a difference ADA2 makes: Insights into the pathophysiology of ADA2 deficiency from single-cell RNA sequencing of monocytes.

Abstract

Discussion on the increase in nonclassical monocytes in patients with DADA2 as shown by scRNA seq; these pro inflammatory cells also show increased TNFR2, type I, and type II IFN pathway gene expression. In this issue of the Journal of Leukocyte Biology,Watanabe et al.1 provide us with novel insights into the pathophysiology of ADA2 deficiency (DADA2). DADA2 is a rare autosomal recessive autoinflammatory condition caused by biallelic loss-of-function mutations in the ADA2 gene, encoding adenosine deaminase 2, resulting in reduced or absent plasma ADA2 enzymatic activity.2,3 DADA2 displays an extended phenotype comprising fevers, vasculopathy (ranging from livedo racemosa to polyarteritis nodosa and life-threatening lacunar stroke or central nervous system hemorrhage), bone marrow failure, and immunodeficiency.4 The ADA2 gene is located at a highly polymorphic locus on 22q11.1. Many structural variations have been described.