Page 48 - Annual report 2021-22

Annual Report 2021-22 |

and a complicated graft preparation process. Moreover, no “Made in India” bioengineered skin graft
is available for clinical use and importing these materials is costly and impractical due to their short
shelf-life. Implantation of isolated epidermal and dermal cells is a viable alternative. However, the
implanted primary cells need structural and microenvironmental support for proper growth and
function. This structural and microenvironment support is provided by the extracellular matrix (ECM)
in normal skin. In severe wounds, there is a significant loss of ECM, hence transplantation of cultured 31
skin cells does not yield expected outcomes due to the poor mechanical and structural support.
Development of an easy indigenous technique for making a clinically viable bioengineered autologous
skin cell graft would be beneficial for millions of patients. Keeping these in mind, an autologous cell
embedded bio-scaffold is being developed as a complete skin substitute.
MicroRNAs in vitiligo skin

Identification of the repair response pathways in melanocytes that are activated during pigmentation
with an implication towards their loss in vitiligo. miRNAs were successfully extracted and enriched
from pigmented vs depigmented skin (day 14 post-wound) of 5 vitiligo patients. Data was normalized
and differentially expressed miRNAs were identified in depigmented skin (compared to pigmented
skin). Real-time PCR was used to validate some of the most upregulated and downregulated miRNAs
in vitiligo skin during wound healing. Commercially available stem cell lines (H9ESCs stem cell HSCs /
IMR90 hiPSC) have been used for differentiation and generation of organoids instead of
reprogramming.

Bioscaffolds for skin therapeutics

Archana’s group has developed a simple way of making cell embedded scaffolds using the
polyelectrolyte complexation (PEC) technique, utilizing chitosan (CH) as a positively charged polymer
and a mixture of chondroitin sulphate (CS) and hyaluronic acid (HA) as negatively charged polymers.
When these polymer solutions are mixed, there is spontaneous electrostatic interaction leading to the
formation of a cross-linked scaffold. As this technique produces no by-products and only uses a
polymer solution for making the scaffold, primary skin cells can be added easily during the scaffold
formation process. Two different compositions of the PEC, one with CH and CS (CH-CS PEC), another
with CH and CS+HA [CH-(CS-HA) PEC] were explored, for their ability for the complete grafting of
keratinocyte and fibroblast cells. Following physicochemical characterization, hemocompatibility and
protein adsorption studies, the scaffold's ability to engraft keratinocytes was evaluated by microscopic
examination. Finally, expression of proliferation and functional markers by the keratinocyte cells were
compared between seeded and grafted cells on the same scaffold, to understand the impact of
complete cellular grafting on the cellular behaviour. In future, this study will lead to the differences
between grafted and seeded cells using cellular and molecular assays. This includes analysis of
proliferation and differentiation markers of keratinocytes, melanocytes and fibroblasts using
quantitative PCR based methods.