ALK5 inhibitor impact on bleomycin-induced systemic sclerosis mouse model via multifunctional optical coherence
Pavel V Nikitin1, Harshdeep S Chawla1, Jessica Gutierrez1
1Department of Biomedical Engineering, University of Houston, 3517 Cullen Blvd, Houston, Texas 77204, USA.
APL Bioengineering
|November 10, 2025
Summary
Multifunctional optical coherence tomography (OCT) noninvasively assesses skin changes in a systemic sclerosis (SSc) mouse model. This technique shows promise for monitoring disease progression and evaluating treatments like SB 525334.
Area of Science:
- Biomedical Engineering
- Rheumatology
- Optical Imaging
Background:
- Systemic sclerosis (SSc) is a severe autoimmune disease marked by fibrosis and vascular issues.
- Noninvasive imaging is vital for tracking SSc progression and treatment efficacy.
- Current methods may lack the comprehensive assessment needed for SSc.
Purpose of the Study:
- To evaluate the feasibility of multifunctional optical coherence tomography (OCT) for assessing skin changes in a murine SSc model.
- To quantitatively measure skin thickness, stiffness, and microvasculature noninvasively.
- To explore OCT's potential for monitoring SSc pathogenesis and therapeutic responses.
Main Methods:
- Utilized a bleomycin-induced murine model of systemic sclerosis (SSc).
- Employed multifunctional optical coherence tomography (OCT), including OCT angiography and elastography.
- Assessed skin thickness, stiffness, and microvasculature changes longitudinally.
- Administered SB 525334, a TGF-β1 receptor ALK5 inhibitor, as a therapeutic intervention.
Main Results:
- Bleomycin treatment significantly increased skin thickness, stiffness, and vessel lumen width, indicating fibrosis and vascular changes.
- Multifunctional OCT successfully detected these structural, biomechanical, and vascular alterations.
- SB 525334 treatment partially reversed the bleomycin-induced changes in skin properties.
Conclusions:
- Multifunctional OCT is a technically feasible, noninvasive method for monitoring experimental SSc.
- The technique can quantify fibrosis and vascular dysfunction, key SSc hallmarks.
- This approach shows potential for evaluating novel SSc therapies like TGF-β inhibitors.


