S.BIOMEDICS

Treatment of Critical Limb Ischemia FECS-Ad Allogeneic Adipose-derived Mesenchymal Stem Cell Spheroids

Critical Limb Ischemia: Peripheral arterial disease causing ulcer and necrosis of tissues due to blockage of lower limb vessels

Cause: Developed from a worsened case of peripheral arterial disease caused by a decrease in blood flow due to angiostenosis, occlusion, or obstruction of the lower limb vessels Occurs as a complication of diseases such as smoking, high blood pressure, and diabetes
Symptom: It usually causes severe ischemic pain and if it is developed further, it causes skin ulcers or tissue necrosis.
Delayed treatment may result in the need to amputate the limbs within 6 months.

Basic Research	Non-clinical	Phase 1	Phase 2	Phase 3	Approval
Phase 1/2a

DATA

Secretion of Blood Vessel Regeneration Factors

The cytokines (IL-6, IL-8) and growth factors (VEGF, b-FGF) related to tissue regeneration and angiogenesis show a superior generation rate in FECS-Ad to 2D culture method (2D) and other 3D technology.

Vascular Tissue Regeneration

Visual observation

PBS (negative control), 2D mesenchymal stem cells (2D MSC) and FECS-Ad were injected into the muscular tissue of nude mice in order to confirm the angiogenesis effect. As a result, a large number of red blood vessels were observed in the tissue injected with FECS-Ad.

PBS

No vascular tissue observed
2D MSC

Some vascular tissues observed
FECS-Ad

A number of vascular tissues observed

Immunofluorescence staining

Immunofluorescence staining using anti-CD31 and anti-αSMA antibodies, vascular endothelial cell markers, was carried out in order to confirm angiogenesis in the tissue. Whereas few to no vascular endothelial cells were observed in the negative control group (PBS), a large amount of CD31 and αSMA were observed in the group administered with FECS-Ad. As they form a tubular structure, the regeneration of vascular tissues was confirmed.

- Normal control group
- FECS-Ad Day 14
- PBS Day 14
- FECS-Ad Day 28
CD31 and HNA
- Normal control group
- FECS-Ad Day 14
- PBS Day 14
- FECS-Ad Day 28
αSMA

Tissue Fibrosis Improvement

As a result of staining the muscle tissue of the administration site using Hematoxylin and Eosin (H&E) and Masson's Trichrome (MT), little to no tissue fibrosis was observed in the group administered with the test substance (FECS-Ad) and it shows a pattern similar to that of the normal tissue (positive control group) whereas large amounts of tissue fibrosis were observed in the negative control group (PBS).

- Normal tissue
- FECS-Ad Day 14
- PBS Day 14
- FECS-Ad Day 28
H&E
- Normal tissue
- FECS-Ad Day 14
- PBS Day 14
- FECS-Ad Day 28
MT

Effect of Lower Limb Regeneration

When PBS (negative control) was administered to an animal model for lower limb ischemia, the tissue was necrotized and the loss of the limb occurred from Day 7. When 2D cultured mesenchymal stem cells (2D MSC) were administered, the blood flow partially improved but did not recover up to the feet area. In the group administered with FECS-Ad, the blood flow improved from Day 7 of observation, and on Day 28, the lower limb and feet were regenerated completely.

	Day 0	Day 7	Day 14	Day 21	Day 28
PBS
2D MSC
FECS-Ad