Development of engineering product 3D cell culture systems designed for airway modelling

Chronic airway diseases have a complex set of mechanisms in which environmental and genetic factors play a role. It is very important to study the molecular pathologies of these diseases and to establish suitable cellular model systems that mimic the in vivo environment for tissue transplantation needed after critical surgical operations. Various cellular in vitro model systems have been created in the literature to model the airway. The most prevalent in vitro model for airway cell cultures is the air-liquid interface (ALI)-culture system, which uses transwell-insert membrane structures. However, in current ALI cell culture applications, since there is no practical system design that can seed both sides of transwell membranes, the ALI culture system can not sufficient when examining cell-cell interaction. The tendency of commercially available systems to 3D cell culture systems is also extremely limited. In the first step of the thesis; the use of transwells currently used in ALI culture systems has been modified by making them more effective and for this purpose, transwell adapters have been printed from a 3D printer, leak tests have been carried out and epithelial-fibroblast co-cultures have been made by adapting them to the ALI system. Immunocytochemistry and real-time PCR studies were performed on co-culture models and the effectiveness of the models was verified. As a result of the trials, a new product has been developed that transforms it into a 3D co-culture system. In the second part of the study, biodegradable membranes were produced for epithelial tissue graft formation and application in transwell inserts. For this purpose, nonwoven nanofiber mesh membranes were synthesized by electrospinning method using the polymers poly (L-lactic acid) (PL24, Corbion, intrinsic viscosity=1.5-2.0 dL/g) and poly(e-caprolactone) (PCL12, Corbion, intrinsic viscosity=1.0-1.3 dL/g). After the optimization and characterization studies were carried out, the suitable membranes were integrated into the 3D ALI culture-system and evaluated in cell culture systems. The constructed biodegradable membrane was shown to be sustainable, similar to the barrier structure seen in the physiological environment, and acceptable for application in ALI-culture systems for airway modeling.