bims-actimu Biomed News
on Actinopathies in inborn errors of immunity
Issue of 2024–12–08
three papers selected by
Elodie Busch, University of Strasbourg



  1. J Pediatr Clin Pract. 2024 Dec;14 200128
      We present a case of X-linked thrombocytopenia (XLT) with a novel WAS gene variant expressing a normal amount of Wiskott-Aldrich syndrome protein (WASp) in lymphocytes. XLT usually decreases WASp expression not only in platelets, but also in lymphocytes. However, there were cases, such as the present one, in which WASp was expressed normally in lymphocytes and absent only in platelets. Our finding suggests that it is of greater diagnostic sensitivity to perform an expression analysis of WASp in both platelets and lymphocytes when XLT is suspected.
    Keywords:  Wiskott-Aldrich syndrome protein; X-linked thrombocytopenia; lymphocyte; novel variant
    DOI:  https://doi.org/10.1016/j.jpedcp.2024.200128
  2. Cell Death Dis. 2024 Dec 01. 15(11): 871
      DOCK8 deficiency has been shown to affect the migration, function, and survival of immune cells in innate and adaptive immune responses. The immunological mechanisms underlying autosomal recessive (AR) hyper-IgE syndrome (AR-HIES) caused by DOCK8 mutations remain unclear, leading to a lack of specific therapeutic options. In this study, we used CRISPR/Cas9 technology to develop a mouse model with a specific DOCK8 point mutation in exon 45 (c.5846C>A), which is observed in patients with AR-HIES. We then investigated the effect of this mutation on B cell development, cell metabolism, and function in a mouse model with Dock8 gene mutation. The results demonstrated that Dock8 gene mutation inhibited splenic MZ and GC B cell development and crippled BCR signaling. In addition, it resulted in enhanced glycolysis in B cells. Mechanistically, the reduced BCR signaling was related to decreased B cell spreading, BCR clustering, and signalosomes, mediated by inhibited activation of WASP. Furthermore, the DOCK8 mutation led to increased expression of c-Myc in B cells, which plays an important role in glycolysis. As such, GC B cells' formation and immune responses were disturbed in LCMV-infected mice. These findings will provide new insights into the immunological pathogenesis of primary immunodeficiency disorder caused by DOCK8 mutation.
    DOI:  https://doi.org/10.1038/s41419-024-07180-w
  3. Pediatr Allergy Immunol. 2024 Dec;35(12): e70003
      
    Keywords:  CARMIL2; India; Molluscum contagiosum; combined immunodeficiency; eczema
    DOI:  https://doi.org/10.1111/pai.70003