Limits...
Superficial dsg2 expression limits epidermal blister formation mediated by pemphigus foliaceus antibodies and exfoliative toxins.

Brennan D, Hu Y, Medhat W, Dowling A, Mahoney MG - Dermatol Res Pract (2010)

Bottom Line: Cell-cell adhesion mediated by desmosomes is crucial for maintaining proper epidermal structure and function, as evidenced by several severe and potentially fatal skin disorders involving impairment of desmosomal proteins.We showed that ectopic expression of Dsg2 reduced the extent of blister formation in response to both ETA and PF Ig.Collectively, our data support the role for Dsg2 in cell adhesion and suggest that ectopic superficial expression of Dsg2 can increase membrane preservation of Dsg1 and limit epidermal blister formation mediated by PF antibodies and exfoliative toxins.

View Article: PubMed Central - PubMed

Affiliation: Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.

ABSTRACT
Cell-cell adhesion mediated by desmosomes is crucial for maintaining proper epidermal structure and function, as evidenced by several severe and potentially fatal skin disorders involving impairment of desmosomal proteins. Pemphigus foliaceus (PF) and staphylococcal scalded skin syndrome (SSSS) are subcorneal blistering diseases resulting from loss of function of the desmosomal cadherin, desmoglein 1 (Dsg1). To further study the pathomechanism of these diseases and to assess the adhesive properties of Dsg2, we employed a recently established transgenic (Tg) mouse model expressing Dsg2 in the superficial epidermis. Neonatal Tg and wild type (WT) mice were injected with purified ETA or PF Ig. We showed that ectopic expression of Dsg2 reduced the extent of blister formation in response to both ETA and PF Ig. In response to PF Ig, we observed either a dramatic loss or a reorganization of Dsg1-alpha, Dsg1-beta, and, to a lesser extent, Dsg1-gamma, in WT mice. The Inv-Dsg2 Tg mice showed enhanced retention of Dsg1 at the cell-cell border. Collectively, our data support the role for Dsg2 in cell adhesion and suggest that ectopic superficial expression of Dsg2 can increase membrane preservation of Dsg1 and limit epidermal blister formation mediated by PF antibodies and exfoliative toxins.

No MeSH data available.


Related in: MedlinePlus

Dsg2 offers protection against PF Ig-induced acantholysis. (a) Newborn WT and Inv-Dsg2 Tg mice were injected subcutaneously with 10 mg of purified PF Ig for 18 hours. Gross blisters were more pronounced in WT mice, as compared to Tg mice. (b) Mice were sacrificed, and their skin was processed for histology, revealing more dramatic blisters in the WT (n = 6) than in Tg mice (n = 10). Top panels show 3X magnification, and lower panels show 40X magnification of the site of blister formation (arrows). (c) The extent of blistering was graded as described in Figure 2. Each dot represents one animal. The average blister scores were 4.0 ± 0.0 for WT mice and 2.1 ± 0.7 for Tg mice. These values were statistically significant, P ≤  .000022 (2-tailed unequal variance) or ≤  .000012 (1-tailed unequal variance). (d) Back skin biopsies of WT and Tg mice treated with PF Ig were homogenized in Laemmli buffer, the proteins were resolved with SDS-PAGE and immunoblotted for Dsg1 (27B2), Dsg2, and Actin. Western blotting demonstrates that superficial Dsg2 slightly enhances retention of Dsg1 in response to PF Ig.
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fig4: Dsg2 offers protection against PF Ig-induced acantholysis. (a) Newborn WT and Inv-Dsg2 Tg mice were injected subcutaneously with 10 mg of purified PF Ig for 18 hours. Gross blisters were more pronounced in WT mice, as compared to Tg mice. (b) Mice were sacrificed, and their skin was processed for histology, revealing more dramatic blisters in the WT (n = 6) than in Tg mice (n = 10). Top panels show 3X magnification, and lower panels show 40X magnification of the site of blister formation (arrows). (c) The extent of blistering was graded as described in Figure 2. Each dot represents one animal. The average blister scores were 4.0 ± 0.0 for WT mice and 2.1 ± 0.7 for Tg mice. These values were statistically significant, P ≤  .000022 (2-tailed unequal variance) or ≤  .000012 (1-tailed unequal variance). (d) Back skin biopsies of WT and Tg mice treated with PF Ig were homogenized in Laemmli buffer, the proteins were resolved with SDS-PAGE and immunoblotted for Dsg1 (27B2), Dsg2, and Actin. Western blotting demonstrates that superficial Dsg2 slightly enhances retention of Dsg1 in response to PF Ig.

Mentions: Next, we wanted to assess whether ectopic expression of Dsg2 could protect against skin blister formation induced by PF pathogenic antibodies. We purified Ig from the sera of PF patients with the active disease and performed passive transfer of the PF Ig into newborn WT and Tg mice. We, and others, have shown that mice injected with normal human Ig do not develop skin blister formation [6]. In accordance with the literature, we observed extensive gross blisters in WT mice 18 hours after injection with PF Ig [6]. However, the Inv-Dsg2 Tg mice injected with PF Ig developed significantly less extensive blisters (Figure 4(a)). The severity of skin blistering was similar between gross observation and histological analysis (Figure 4(b)). Again similar to the blistering observed with ETA in Figure 2, we observed a slight downward shift in the site of blister formation in Tg, as compared to WT, skin (Figure 4(b), lower panels). The extent of histological blistering was then graded, and the results showed that Tg mice were less susceptible to blister formation in response to PF Ig (Figure 4(c)). Thus, ectopic expression of Dsg2 in the superficial epidermis rendered the Tg mice more resistant to PF Ig-induced skin blisters.


Superficial dsg2 expression limits epidermal blister formation mediated by pemphigus foliaceus antibodies and exfoliative toxins.

Brennan D, Hu Y, Medhat W, Dowling A, Mahoney MG - Dermatol Res Pract (2010)

Dsg2 offers protection against PF Ig-induced acantholysis. (a) Newborn WT and Inv-Dsg2 Tg mice were injected subcutaneously with 10 mg of purified PF Ig for 18 hours. Gross blisters were more pronounced in WT mice, as compared to Tg mice. (b) Mice were sacrificed, and their skin was processed for histology, revealing more dramatic blisters in the WT (n = 6) than in Tg mice (n = 10). Top panels show 3X magnification, and lower panels show 40X magnification of the site of blister formation (arrows). (c) The extent of blistering was graded as described in Figure 2. Each dot represents one animal. The average blister scores were 4.0 ± 0.0 for WT mice and 2.1 ± 0.7 for Tg mice. These values were statistically significant, P ≤  .000022 (2-tailed unequal variance) or ≤  .000012 (1-tailed unequal variance). (d) Back skin biopsies of WT and Tg mice treated with PF Ig were homogenized in Laemmli buffer, the proteins were resolved with SDS-PAGE and immunoblotted for Dsg1 (27B2), Dsg2, and Actin. Western blotting demonstrates that superficial Dsg2 slightly enhances retention of Dsg1 in response to PF Ig.
© Copyright Policy - open-access
Related In: Results  -  Collection

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fig4: Dsg2 offers protection against PF Ig-induced acantholysis. (a) Newborn WT and Inv-Dsg2 Tg mice were injected subcutaneously with 10 mg of purified PF Ig for 18 hours. Gross blisters were more pronounced in WT mice, as compared to Tg mice. (b) Mice were sacrificed, and their skin was processed for histology, revealing more dramatic blisters in the WT (n = 6) than in Tg mice (n = 10). Top panels show 3X magnification, and lower panels show 40X magnification of the site of blister formation (arrows). (c) The extent of blistering was graded as described in Figure 2. Each dot represents one animal. The average blister scores were 4.0 ± 0.0 for WT mice and 2.1 ± 0.7 for Tg mice. These values were statistically significant, P ≤  .000022 (2-tailed unequal variance) or ≤  .000012 (1-tailed unequal variance). (d) Back skin biopsies of WT and Tg mice treated with PF Ig were homogenized in Laemmli buffer, the proteins were resolved with SDS-PAGE and immunoblotted for Dsg1 (27B2), Dsg2, and Actin. Western blotting demonstrates that superficial Dsg2 slightly enhances retention of Dsg1 in response to PF Ig.
Mentions: Next, we wanted to assess whether ectopic expression of Dsg2 could protect against skin blister formation induced by PF pathogenic antibodies. We purified Ig from the sera of PF patients with the active disease and performed passive transfer of the PF Ig into newborn WT and Tg mice. We, and others, have shown that mice injected with normal human Ig do not develop skin blister formation [6]. In accordance with the literature, we observed extensive gross blisters in WT mice 18 hours after injection with PF Ig [6]. However, the Inv-Dsg2 Tg mice injected with PF Ig developed significantly less extensive blisters (Figure 4(a)). The severity of skin blistering was similar between gross observation and histological analysis (Figure 4(b)). Again similar to the blistering observed with ETA in Figure 2, we observed a slight downward shift in the site of blister formation in Tg, as compared to WT, skin (Figure 4(b), lower panels). The extent of histological blistering was then graded, and the results showed that Tg mice were less susceptible to blister formation in response to PF Ig (Figure 4(c)). Thus, ectopic expression of Dsg2 in the superficial epidermis rendered the Tg mice more resistant to PF Ig-induced skin blisters.

Bottom Line: Cell-cell adhesion mediated by desmosomes is crucial for maintaining proper epidermal structure and function, as evidenced by several severe and potentially fatal skin disorders involving impairment of desmosomal proteins.We showed that ectopic expression of Dsg2 reduced the extent of blister formation in response to both ETA and PF Ig.Collectively, our data support the role for Dsg2 in cell adhesion and suggest that ectopic superficial expression of Dsg2 can increase membrane preservation of Dsg1 and limit epidermal blister formation mediated by PF antibodies and exfoliative toxins.

View Article: PubMed Central - PubMed

Affiliation: Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.

ABSTRACT
Cell-cell adhesion mediated by desmosomes is crucial for maintaining proper epidermal structure and function, as evidenced by several severe and potentially fatal skin disorders involving impairment of desmosomal proteins. Pemphigus foliaceus (PF) and staphylococcal scalded skin syndrome (SSSS) are subcorneal blistering diseases resulting from loss of function of the desmosomal cadherin, desmoglein 1 (Dsg1). To further study the pathomechanism of these diseases and to assess the adhesive properties of Dsg2, we employed a recently established transgenic (Tg) mouse model expressing Dsg2 in the superficial epidermis. Neonatal Tg and wild type (WT) mice were injected with purified ETA or PF Ig. We showed that ectopic expression of Dsg2 reduced the extent of blister formation in response to both ETA and PF Ig. In response to PF Ig, we observed either a dramatic loss or a reorganization of Dsg1-alpha, Dsg1-beta, and, to a lesser extent, Dsg1-gamma, in WT mice. The Inv-Dsg2 Tg mice showed enhanced retention of Dsg1 at the cell-cell border. Collectively, our data support the role for Dsg2 in cell adhesion and suggest that ectopic superficial expression of Dsg2 can increase membrane preservation of Dsg1 and limit epidermal blister formation mediated by PF antibodies and exfoliative toxins.

No MeSH data available.


Related in: MedlinePlus