AbstractAutosomal recessive congenital ichthyosis (ARCI) is a cornification disorder of the epidermis characterised by extensive scaling and marked erythroderma and increased transepidermal water loss (TEWL). Currently only symptomatic therapeutics are available, but current research is focussing on enzyme replacement therapy using recombinant transglutaminase 1 (TGase-1), a protein involved in crosslinking the cornified envelope in the stratum corneum of the skin, along with skin models mimicking the ARCI phenotype to create a causative therapy, the first for ARCI patients.
Knockdown of TGM1 was utilised with small interfering RNA in primary keratinocytes. Recombinant human TGase-1 (rhTGase-1) produced in bacteria, human and insect cells were separately transfected into cultured keratinocytes using a protein transfection kit and cellular localisation was visualised by immunocytochemistry. The activities of each rhTGase-1 were also measured through a specific keratinocyte TGase-1 assay kit to investigate how stable the protein was after transfection.
Results from knocked down keratinocytes transfected with recombinant TGase-1 showed that rhTGase-1 from human and insect cells localised to the plasma membrane of differentiated keratinocytes whereas rhTGase-1 produced in bacteria mostly localised in the cytoplasm, likely due to lack of posttranslational modifications.
The results demonstrated for the first time that rhTGase-1 produced in human cells localised to the cell membrane in cultured TGM1 knockdown keratinocytes, showing its potential as a therapeutic drug for future causative therapy of TGM1 pathogenic ARCI.
|Date of Award
|27 Jul 2022
|Hans Hennies (Main Supervisor) & Roger Phillips (Co-Supervisor)