1. |
- Chu, Yuanyuan, et al.
(author)
-
A20 and CYLD Do Not Share Significant Overlapping Functions during B Cell Development and Activation
- 2012
-
In: Journal of Immunology. - : The American Association of Immunologists. - 1550-6606 .- 0022-1767. ; 189:9, s. 4437-4443
-
Journal article (peer-reviewed)abstract
- The ubiquitin-editing enzyme A20 (TNFAIP3) and the deubiquitinase CYLD are central negative regulators of NF-kappa B signaling. Both can act by removing nonproteolytic K63-linked polyubiquitin chains from an overlapping set of signaling molecules. In B cells, A20 deficiency results in hyperactivity, loss of immune homeostasis, inflammation, and autoimmunity. The reported consequences of CYLD deficiency are controversial, ranging from an absence of effects to dramatic B cell hyperplasia. These differences could be due to varying compensation for the loss of CYLD function by A20. Therefore, to explore potential overlapping physiological functions between A20 and CYLD, we generated and characterized A20/CYLD double-deficient B cells. Interestingly, the lack of both A20 and CYLD did not exacerbate the developmental defects and hyperresponsive activity of A20-deficient B cells. In addition, the extent of B cell activation after in vitro stimulation with anti-CD40, LPS, and CpG was comparable in B cells lacking A20/CYLD and A20 alone. However, in response to BCR cross-linking, we observed small but reproducible additive effects of the lack of A20 and CYLD. Taken together, our results demonstrate that A20 and CYLD do not share significant functions during B cell development and activation. The Journal of Immunology, 2012, 189: 4437-4443.
|
|
2. |
- Kumar, Manish, et al.
(author)
-
MicroRNA let-7 Modulates the Immune Response to Mycobacterium tuberculosis Infection via Control of A20, an Inhibitor of the NF-κB Pathway.
- 2015
-
In: Cell host & microbe. - : elsevier. - 1934-6069 .- 1931-3128. ; 17:3, s. 345-56
-
Journal article (peer-reviewed)abstract
- The outcome of the interaction between Mycobacterium tuberculosis (Mtb) and a macrophage depends on the interplay between host defense and bacterial immune subversion mechanisms. MicroRNAs critically regulate several host defense mechanisms, but their role in the Mtb-macrophage interplay remains unclear. MicroRNA profiling of Mtb-infected macrophages revealed the downregulation of miR-let-7f in a manner dependent on the Mtb secreted effector ESAT-6. We establish that let-7f targets A20, a feedback inhibitor of the NF-κB pathway. Expression of let-7f decreases and A20 increases with progression of Mtb infection in mice. Mtb survival is attenuated in A20-deficient macrophages, and the production of TNF, IL-1β, and nitrite, which are mediators of immunity to Mtb, is correspondingly increased. Further, let-7f overexpression diminishes Mtb survival and augments the production of cytokines including TNF and IL-1β. These results uncover a role for let-7f and its target A20 in regulating immune responses to Mtb and controlling bacterial burden.
|
|
3. |
|
|
4. |
- Yang, Yunlong, et al.
(author)
-
The PDGF-BB-SOX7 axis-modulated IL-33 in pericytes and stromal cells promotes metastasis through tumour-associated macrophages
- 2016
-
In: Nature Communications. - : NATURE PUBLISHING GROUP. - 2041-1723. ; 7:11385
-
Journal article (peer-reviewed)abstract
- Signalling molecules and pathways that mediate crosstalk between various tumour cellular compartments in cancer metastasis remain largely unknown. We report a mechanism of the interaction between perivascular cells and tumour-associated macrophages (TAMs) in promoting metastasis through the IL-33-ST2-dependent pathway in xenograft mouse models of cancer. IL-33 is the highest upregulated gene through activation of SOX7 transcription factor in PDGF-BB-stimulated pericytes. Gain-and loss-of-function experiments validate that IL-33 promotes metastasis through recruitment of TAMs. Pharmacological inhibition of the IL-33-ST2 signalling by a soluble ST2 significantly inhibits TAMs and metastasis. Genetic deletion of host IL-33 in mice also blocks PDGF-BB-induced TAM recruitment and metastasis. These findings shed light on the role of tumour stroma in promoting metastasis and have therapeutic implications for cancer therapy.
|
|