Limits...
PAR2 absence completely rescues inflammation and ichthyosis caused by altered CAP1/Prss8 expression in mouse skin.

Frateschi S, Camerer E, Crisante G, Rieser S, Membrez M, Charles RP, Beermann F, Stehle JC, Breiden B, Sandhoff K, Rotman S, Haftek M, Wilson A, Ryser S, Steinhoff M, Coughlin SR, Hummler E - Nat Commun (2011)

Bottom Line: K14-CAP1/Prss8 ectopic expression impairs epidermal barrier function and causes skin inflammation characterized by an increase in thymic stromal lymphopoietin levels and immune cell infiltrations.Strikingly, both gross and functional K14-CAP1/Prss8-induced phenotypes are completely negated when superimposed on a PAR2- background, establishing PAR2 as a pivotal mediator of pathogenesis.Our data provide genetic evidence for PAR2 as a downstream effector of CAP1/Prss8 in a signalling cascade that may provide novel therapeutic targets for ichthyoses, pruritus and inflammatory skin diseases.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmacology and Toxicology, University of Lausanne, Lausanne 1005, Switzerland.

ABSTRACT
Altered serine protease activity is associated with skin disorders in humans and in mice. The serine protease channel-activating protease-1 (CAP1; also termed protease serine S1 family member 8 (Prss8)) is important for epidermal homeostasis and is thus indispensable for postnatal survival in mice, but its roles and effectors in skin pathology are poorly defined. In this paper, we report that transgenic expression in mouse skin of either CAP1/Prss8 (K14-CAP1/Prss8) or protease-activated receptor-2 (PAR2; Grhl3(PAR2/+)), one candidate downstream target, causes epidermal hyperplasia, ichthyosis and itching. K14-CAP1/Prss8 ectopic expression impairs epidermal barrier function and causes skin inflammation characterized by an increase in thymic stromal lymphopoietin levels and immune cell infiltrations. Strikingly, both gross and functional K14-CAP1/Prss8-induced phenotypes are completely negated when superimposed on a PAR2- background, establishing PAR2 as a pivotal mediator of pathogenesis. Our data provide genetic evidence for PAR2 as a downstream effector of CAP1/Prss8 in a signalling cascade that may provide novel therapeutic targets for ichthyoses, pruritus and inflammatory skin diseases.

No MeSH data available.


Related in: MedlinePlus

Ichthyosis and inflammation are absent in K14-CAP1/Prss8:PAR2−/− mice.(a) Macroscopic appearance of 2-week-old animals. H&E: haematoxylin and eosin staining of skin. Immunofluorescence (green) shows transgenic CAP1/Prss8 expression at the basal layer in K14-CAP1/Prss8:PAR2+/+, K14-CAP1/Prss8:PAR2+/− and K14-CAP1/Prss8:PAR2−/− transgenic mice. Below: negative control (omission of primary antibody, no 1Ab). Nuclei were counterstained with DAPI (blue), n≥3 mice per group. Bar represents 20 μm. (b) RT–PCR analysis demonstrates expression of the CAP1/Prss8 transgene in K14-CAP1/Prss8:PAR2+/+, K14-CAP1/Prss8:PAR2+/− and K14-CAP1/Prss8:PAR2−/− transgenic mice, and absence of PAR2 gene expression in PAR2−/− animals. β-actin was used to control cDNA, and H2O provided negative control. The blot is representative of three animals analysed per group. (c) Transepidermal water loss and body weight analyses (d) in experimental and control animals, n≥8 mice per group. *P<0.05, **P<0.01, ***P<0.001. (e) Numbers (nb.) of F4/80- and (f) S100-positive cells evident in the skin of 2-week-old animals; (e, f) n=3 mice per genotype. **P<0.01, ***P<0.001. All data are presented as mean±s.e.m.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3105307&req=5

f6: Ichthyosis and inflammation are absent in K14-CAP1/Prss8:PAR2−/− mice.(a) Macroscopic appearance of 2-week-old animals. H&E: haematoxylin and eosin staining of skin. Immunofluorescence (green) shows transgenic CAP1/Prss8 expression at the basal layer in K14-CAP1/Prss8:PAR2+/+, K14-CAP1/Prss8:PAR2+/− and K14-CAP1/Prss8:PAR2−/− transgenic mice. Below: negative control (omission of primary antibody, no 1Ab). Nuclei were counterstained with DAPI (blue), n≥3 mice per group. Bar represents 20 μm. (b) RT–PCR analysis demonstrates expression of the CAP1/Prss8 transgene in K14-CAP1/Prss8:PAR2+/+, K14-CAP1/Prss8:PAR2+/− and K14-CAP1/Prss8:PAR2−/− transgenic mice, and absence of PAR2 gene expression in PAR2−/− animals. β-actin was used to control cDNA, and H2O provided negative control. The blot is representative of three animals analysed per group. (c) Transepidermal water loss and body weight analyses (d) in experimental and control animals, n≥8 mice per group. *P<0.05, **P<0.01, ***P<0.001. (e) Numbers (nb.) of F4/80- and (f) S100-positive cells evident in the skin of 2-week-old animals; (e, f) n=3 mice per genotype. **P<0.01, ***P<0.001. All data are presented as mean±s.e.m.

Mentions: To address whether CAP1/Prss8 can trigger PAR2 activation in vivo and to experimentally test whether the similarities between Grhl3PAR2/+ and K14-CAP1/Prss8 transgenic animals were due to excessive PAR2 activation in both models, we crossed K14-CAP1/Prss8 transgenic mice from line 2 with mice constitutively and globally deficient in PAR2 (PAR2−/−) that do not exhibit obvious skin abnormalities36. Mice carrying the K14-CAP1/Prss8 transgene that were either wt (K14-CAP1/Prss8) or heterozygous mutant for PAR2 (K14-CAP1/Prss8:PAR2+/−) displayed scaly skin with epidermal hyperplasia (Fig. 6a). In contrast, no scaling, epidermal hyperplasia or premature lethality was observed in K14-CAP1/Prss8 transgenic mice that were homozygous mutant for PAR2 (K14-CAP1/Prss8:PAR2−/−, Fig. 6a and Table 1). Despite the absence of PAR2, these mice still expressed the K14-CAP1/Prss8 transgene (Fig. 6a,b). The rescue was also evident functionally, as K14-CAP1/Prss8:PAR2−/− mice exhibited TEWL in the same range as that of wt controls but significantly different from that of K14-CAP1/Prss8:PAR2+/+ littermates (Fig. 6c). Moreover, whereas K14-CAP1/Prss8 mice displayed a significantly lower body weight compared with controls, the K14-CAP1/Prss8:PAR2−/− mice were indistinguishable from littermate controls in this regard (Fig. 6d). Surprisingly, heterozygosity for PAR2 was sufficient to reverse the increased water loss and reduced body weight observed in K14-CAP1/Prss8 transgenic mice, despite persistence of ichthyotic and hyperplastic phenotypes (Fig. 6c,d). Moreover, expression levels of inflammatory markers IL-1α, IL-1β, TSLP and MMP9, as well as of macrophage and dendritic cell markers anti-F4/80 and anti-S100, were indistinguishable from control levels in K14-CAP1/Prss8:PAR2−/− animals (Figs 4c and 6e,f). K14-CAP1/Prss8:PAR2+/− mice manifested an intermediate phenotype, suggesting a dose-dependent effect of PAR2. Thus, absence of PAR2 completely rescued hyperplasia, barrier dysfunction, inflammation and ichthyosis caused by altered CAP1/Prss8 expression in the skin, establishing PAR2 as a pivotal mediator of K14-CAP1/Prss8-driven skin pathology in this model.


PAR2 absence completely rescues inflammation and ichthyosis caused by altered CAP1/Prss8 expression in mouse skin.

Frateschi S, Camerer E, Crisante G, Rieser S, Membrez M, Charles RP, Beermann F, Stehle JC, Breiden B, Sandhoff K, Rotman S, Haftek M, Wilson A, Ryser S, Steinhoff M, Coughlin SR, Hummler E - Nat Commun (2011)

Ichthyosis and inflammation are absent in K14-CAP1/Prss8:PAR2−/− mice.(a) Macroscopic appearance of 2-week-old animals. H&E: haematoxylin and eosin staining of skin. Immunofluorescence (green) shows transgenic CAP1/Prss8 expression at the basal layer in K14-CAP1/Prss8:PAR2+/+, K14-CAP1/Prss8:PAR2+/− and K14-CAP1/Prss8:PAR2−/− transgenic mice. Below: negative control (omission of primary antibody, no 1Ab). Nuclei were counterstained with DAPI (blue), n≥3 mice per group. Bar represents 20 μm. (b) RT–PCR analysis demonstrates expression of the CAP1/Prss8 transgene in K14-CAP1/Prss8:PAR2+/+, K14-CAP1/Prss8:PAR2+/− and K14-CAP1/Prss8:PAR2−/− transgenic mice, and absence of PAR2 gene expression in PAR2−/− animals. β-actin was used to control cDNA, and H2O provided negative control. The blot is representative of three animals analysed per group. (c) Transepidermal water loss and body weight analyses (d) in experimental and control animals, n≥8 mice per group. *P<0.05, **P<0.01, ***P<0.001. (e) Numbers (nb.) of F4/80- and (f) S100-positive cells evident in the skin of 2-week-old animals; (e, f) n=3 mice per genotype. **P<0.01, ***P<0.001. All data are presented as mean±s.e.m.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3105307&req=5

f6: Ichthyosis and inflammation are absent in K14-CAP1/Prss8:PAR2−/− mice.(a) Macroscopic appearance of 2-week-old animals. H&E: haematoxylin and eosin staining of skin. Immunofluorescence (green) shows transgenic CAP1/Prss8 expression at the basal layer in K14-CAP1/Prss8:PAR2+/+, K14-CAP1/Prss8:PAR2+/− and K14-CAP1/Prss8:PAR2−/− transgenic mice. Below: negative control (omission of primary antibody, no 1Ab). Nuclei were counterstained with DAPI (blue), n≥3 mice per group. Bar represents 20 μm. (b) RT–PCR analysis demonstrates expression of the CAP1/Prss8 transgene in K14-CAP1/Prss8:PAR2+/+, K14-CAP1/Prss8:PAR2+/− and K14-CAP1/Prss8:PAR2−/− transgenic mice, and absence of PAR2 gene expression in PAR2−/− animals. β-actin was used to control cDNA, and H2O provided negative control. The blot is representative of three animals analysed per group. (c) Transepidermal water loss and body weight analyses (d) in experimental and control animals, n≥8 mice per group. *P<0.05, **P<0.01, ***P<0.001. (e) Numbers (nb.) of F4/80- and (f) S100-positive cells evident in the skin of 2-week-old animals; (e, f) n=3 mice per genotype. **P<0.01, ***P<0.001. All data are presented as mean±s.e.m.
Mentions: To address whether CAP1/Prss8 can trigger PAR2 activation in vivo and to experimentally test whether the similarities between Grhl3PAR2/+ and K14-CAP1/Prss8 transgenic animals were due to excessive PAR2 activation in both models, we crossed K14-CAP1/Prss8 transgenic mice from line 2 with mice constitutively and globally deficient in PAR2 (PAR2−/−) that do not exhibit obvious skin abnormalities36. Mice carrying the K14-CAP1/Prss8 transgene that were either wt (K14-CAP1/Prss8) or heterozygous mutant for PAR2 (K14-CAP1/Prss8:PAR2+/−) displayed scaly skin with epidermal hyperplasia (Fig. 6a). In contrast, no scaling, epidermal hyperplasia or premature lethality was observed in K14-CAP1/Prss8 transgenic mice that were homozygous mutant for PAR2 (K14-CAP1/Prss8:PAR2−/−, Fig. 6a and Table 1). Despite the absence of PAR2, these mice still expressed the K14-CAP1/Prss8 transgene (Fig. 6a,b). The rescue was also evident functionally, as K14-CAP1/Prss8:PAR2−/− mice exhibited TEWL in the same range as that of wt controls but significantly different from that of K14-CAP1/Prss8:PAR2+/+ littermates (Fig. 6c). Moreover, whereas K14-CAP1/Prss8 mice displayed a significantly lower body weight compared with controls, the K14-CAP1/Prss8:PAR2−/− mice were indistinguishable from littermate controls in this regard (Fig. 6d). Surprisingly, heterozygosity for PAR2 was sufficient to reverse the increased water loss and reduced body weight observed in K14-CAP1/Prss8 transgenic mice, despite persistence of ichthyotic and hyperplastic phenotypes (Fig. 6c,d). Moreover, expression levels of inflammatory markers IL-1α, IL-1β, TSLP and MMP9, as well as of macrophage and dendritic cell markers anti-F4/80 and anti-S100, were indistinguishable from control levels in K14-CAP1/Prss8:PAR2−/− animals (Figs 4c and 6e,f). K14-CAP1/Prss8:PAR2+/− mice manifested an intermediate phenotype, suggesting a dose-dependent effect of PAR2. Thus, absence of PAR2 completely rescued hyperplasia, barrier dysfunction, inflammation and ichthyosis caused by altered CAP1/Prss8 expression in the skin, establishing PAR2 as a pivotal mediator of K14-CAP1/Prss8-driven skin pathology in this model.

Bottom Line: K14-CAP1/Prss8 ectopic expression impairs epidermal barrier function and causes skin inflammation characterized by an increase in thymic stromal lymphopoietin levels and immune cell infiltrations.Strikingly, both gross and functional K14-CAP1/Prss8-induced phenotypes are completely negated when superimposed on a PAR2- background, establishing PAR2 as a pivotal mediator of pathogenesis.Our data provide genetic evidence for PAR2 as a downstream effector of CAP1/Prss8 in a signalling cascade that may provide novel therapeutic targets for ichthyoses, pruritus and inflammatory skin diseases.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmacology and Toxicology, University of Lausanne, Lausanne 1005, Switzerland.

ABSTRACT
Altered serine protease activity is associated with skin disorders in humans and in mice. The serine protease channel-activating protease-1 (CAP1; also termed protease serine S1 family member 8 (Prss8)) is important for epidermal homeostasis and is thus indispensable for postnatal survival in mice, but its roles and effectors in skin pathology are poorly defined. In this paper, we report that transgenic expression in mouse skin of either CAP1/Prss8 (K14-CAP1/Prss8) or protease-activated receptor-2 (PAR2; Grhl3(PAR2/+)), one candidate downstream target, causes epidermal hyperplasia, ichthyosis and itching. K14-CAP1/Prss8 ectopic expression impairs epidermal barrier function and causes skin inflammation characterized by an increase in thymic stromal lymphopoietin levels and immune cell infiltrations. Strikingly, both gross and functional K14-CAP1/Prss8-induced phenotypes are completely negated when superimposed on a PAR2- background, establishing PAR2 as a pivotal mediator of pathogenesis. Our data provide genetic evidence for PAR2 as a downstream effector of CAP1/Prss8 in a signalling cascade that may provide novel therapeutic targets for ichthyoses, pruritus and inflammatory skin diseases.

No MeSH data available.


Related in: MedlinePlus