Company: FTII
Filing Date: 2025-02-14
Form Type: S-4
Source: 0001493152-25-006997
Chunk: 347

Company: FutureTech II Acquisition Corp.
Filing Date: 2025-02-14
Form: S-4
Chunk 347
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 by study endpoints of 1, 4, and 12 weeks with 4 animals per group. Human adipose-derived
AAT was injected subcutaneously (200 μl) in rats to characterize the immune response and tissue remodeling. For this study, AAT was
produced at lab-scale and was not irradiated prior to implantation. New adipocytes infiltrated the implants by one week, increasing in
abundance at later time points. The majority of implant sites had minimal to mild inflammation and appeared to integrate well into existing
host subcutaneous tissue. The implants showed evidence of cell infiltration, vascularization, adipogenesis and intracellular lipid accumulation,
which indicated implant biocompatibility. Infiltration of host cells into AAT from surrounding tissue indicated the potential to promote
regeneration of adipose tissue using AAT as a scaffold. Samples prepared using mild processing reagents appeared to favor earlier adipocyte
infiltration of the implants and a slighter inflammatory reaction compared to acetone processing. Oil Red O staining highlighted the band
of new adipose tissue forming from the edges of the implant at four weeks. Additionally, cells in the center of the matrix stained positive
for CD31, indicated vascular development, which is the necessary prerequisite for formation and maintenance of new adipose tissue. A number
of cells also stained positive for CD44, a cell surface receptor for hyaluronic acid that is expressed on both cells of hematopoietic
and non- hematopoietic origin and is involved in lymphocyte homing. By twelve weeks, the adipose tissue development had progressed further
into the implant and areas of collagen remodeling were observed histologically.

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In vivo biocompatibility in
a rat model. Histology of acellular adipose tissue implants after four weeks in Sprague Dawley rats stained with (A) hematoxylin and
eosin, (B) Oil Red O staining for intracellular lipids, (C) CD31 and (D) CD44 immunofluorescence.

Fat grafting
for soft tissue reconstruction uses lipoaspirate and ASCs enriched from lipoaspirate. To compare AAT to these clinical techniques, we
evaluated biocompatibility and volume retention of human lipoaspirate and cells in an immune-deficient mouse model. Athymic nude mice
(n = 12 per group) each received subcutaneous injections of AAT with and without ASCs. For implants containing ASC