TNF regulates transcription of NLRP3 inflammasome components and inflammatory molecules in cryopyrinopathies
Matthew D. McGeough, Alexander Wree, Maria E. Inzaugarat, Ariela Haimovich, Casey D. Johnson, Carla A. Peña, Raphaela Goldbach-Mansky, Lori Broderick, Ariel E. Feldstein, Hal M. Hoffman
Matthew D. McGeough, Alexander Wree, Maria E. Inzaugarat, Ariela Haimovich, Casey D. Johnson, Carla A. Peña, Raphaela Goldbach-Mansky, Lori Broderick, Ariel E. Feldstein, Hal M. Hoffman
View: Text | PDF
Research Article Immunology Inflammation

TNF regulates transcription of NLRP3 inflammasome components and inflammatory molecules in cryopyrinopathies

Abstract

The NLRP3 inflammasome is a protein complex responsible for caspase-1–dependent maturation of the proinflammatory cytokines IL-1β and IL-18. Gain-of-function missense mutations in NLRP3 cause the disease spectrum known as the cryopyrin-associated periodic syndromes (CAPS). In this study, we generated Nlrp3-knockin mice on various KO backgrounds including Il1b/Il18-, caspase-1–, caspase-11– (Casp1/11-), and Tnf-deficient strains. The Nlrp3L351P Il1b–/– Il18–/– mutant mice survived and grew normally until adulthood and, at 6 months of age, exhibited marked splenomegaly and leukophilia. Injection of these mice with low-dose LPS resulted in elevated serum TNF levels compared with Nlrp3L351P Casp1/11–/– mice and Il1b–/– Il18–/– littermates. Treatment of Nlrp3A350V mice with the TNF inhibitor etanercept resulted in all pups surviving to adulthood, with normal body and spleen/body weight ratios. Nlrp3A350V Tnf–/– mice showed a similar phenotypic rescue, with marked reductions in serum IL-1β and IL-18, reduced myeloid inflammatory infiltrate in the skin and spleen, and substantial decreases in splenic mRNA expression of both inflammasome components (Nlrp3, Pycard, pro-Casp1) and pro-cytokines (Il1b, Il18). Likewise, we observed a reduction in the expression of both pro-Casp1 and pro-Il1b in cultured Nlrp3A350V Tnf–/– BM-derived DCs. Our data show that TNF is an important transcriptional regulator of NLRP3 inflammasome components in murine inflammasomopathies. Moreover, these results may have therapeutic implications for CAPS patients with partial responses to IL-1–targeted therapies.

Authors

Matthew D. McGeough, Alexander Wree, Maria E. Inzaugarat, Ariela Haimovich, Casey D. Johnson, Carla A. Peña, Raphaela Goldbach-Mansky, Lori Broderick, Ariel E. Feldstein, Hal M. Hoffman

×

Figure 5

KO of TNF eliminates inflammatory skin disease in Nlrp3A350V mice.

Options: View larger image (or click on image) Download as PowerPoint
KO of TNF eliminates inflammatory skin disease in Nlrp3A350V mice. (A–D)...
(A–D) IHC of skin sections from Nlrp3A350V mice showed positive staining for F4/80 and MPO, with the presence of neutrophil pockets and a notable loss of s.c. tissue, while skin sections from Nlrp3A350V Tnf–/– mice had a complete absence of these and were indistinguishable from those of control animals. Nlrp3A350V Tnf+/– mice were partially protected, with less F4/80- and MPO-positive staining and increased s.c. tissue compared with skin tissue from Nlrp3A350V mice. Quantification of (B) skin thickness, (C) F4/80-positive cells, and (D) MPO-positive cells. Representative sections and quantification of skin thickness and IHC are from 9 mice in each group. Representative sections in A are oriented with the basal region on the far right of each panel (original magnification, ×10). Scale bar: 200 μm. *P < 0.05, by Kruskal-Wallis with Dunn’s multiple comparisons test. Data represent the mean ± SEM.