Serum levels of the IgA isotype switch factor TGF‐β1 are elevated in patients with COVID‐19
Er‐yi Wang, Hao Chen, Bao‐qing Sun, Hui Wang, Hui‐Qi Qu, Yichuan Liu, Xi‐zhuo Sun, Jingchun Qu, Zhang‐fu Fang, Lifeng Tian, Yi‐feng Zeng, Shau‐Ku Huang, Hakon Hakonarson, Zhi‐gang Liu
FEBS Letters, 2021 Jul;595(13):1819‐1824.
The original version of this article contained errors in the conclusion of the abstract and in the discussion section. In the conclusion of the abstract, it read: ‘the TGF‐β1 activator THBS3’. In the discussion, it read: ‘Thrombospondins activate TGF‐β1 by direct binding with the inactive precursor complex of TGF‐β1, known as latent TGF‐β [12]’.
According to the authors’ personal communication with Professor Joanne Murphy‐Ullrich at the University of Alabama at Birmingham, a leading expert on thrombospondin (TSP)‐1 and TGF‐β1 activation, only the TSP‐1 family member is able to activate latent TGF‐β. The activation sequence (KRFK) present in the TSP‐1 type 1 repeat is critical for latent TGF‐β activation [1]. None of the other TSP family members can activate latent TGF‐β, because they either lack the type 1 repeats entirely (e.g. TSP‐3 encoded by THBS3 [2]) or lack the specific activation sequence (TSP‐2) [3].
As a result, the authors request the following corrections:
In the abstract, it should read: ‘the thrombospondin 3 gene THBS3, homologous to the TGF‐β1 activator THBS1’;
In the discussion, it should read: ‘Thrombospondin‐1 (TSP‐1) activates TGF‐β1 by direct binding to the inactive precursor complex of TGF‐β1, known as latent TGF‐β [12]. The activation sequence (KRFK) in the TSP‐1 second type 1 repeat is critical for latent TGF‐β activation. Thrombospondin‐3 encoded by THBS3 does not activate TGF‐β due to the lack of the type 1 repeats, and its role is still understudied and warrants further exploration’.
References
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