Intercellular adhesion molecule-1 deficiency attenuates the development of skin fibrosis in tight-skin mice

Area of Science:

• Dermatology
• Immunology
• Genetics

Background:

• Systemic sclerosis is characterized by cutaneous fibrosis.
• The tight-skin (TSK/+) mouse model exhibits skin fibrosis due to a fibrillin 1 gene mutation and immunological abnormalities.
• The role of adhesion molecules in TSK/+ mouse skin fibrosis remains uninvestigated.

Purpose of the Study:

• To investigate the role of adhesion molecules, specifically L-selectin and ICAM-1, in the pathogenesis of skin fibrosis in TSK/+ mice.
• To determine if ICAM-1 deficiency or blockade affects skin sclerosis and fibroblast function.

Main Methods:

• Generated TSK/+ mice lacking L-selectin and/or ICAM-1.
• Administered ICAM-1 antisense oligonucleotides to TSK/+ mice.
• Assessed skin sclerosis, T cell infiltration, and fibroblast phenotype/function (growth, collagen synthesis) in response to IL-4 stimulation.

Main Results:

• ICAM-1 deficiency significantly suppressed skin sclerosis by approximately 48% in TSK/+ mice.
• L-selectin deficiency had no significant effect on skin sclerosis.
• ICAM-1 deficiency reduced T cell infiltration into the skin.
• ICAM-1 expression was augmented on TSK/+ dermal fibroblasts stimulated with IL-4.
• Loss or blocking of ICAM-1 suppressed the IL-4-induced upregulation of growth and collagen synthesis in TSK/+ fibroblasts.

Conclusions:

• ICAM-1, particularly on skin fibroblasts, significantly contributes to the development of skin fibrosis in TSK/+ mice.
• ICAM-1 plays a role in T cell migration to fibrotic skin.
• Targeting ICAM-1 may be a potential therapeutic strategy for systemic sclerosis.