The skin is the largest organ of the body and is critical to survival of the organism as a barrier to the environment and for thermal regulation and hydration retention. In order to serve these critical functions, the skin is constantly undergoing renewal and possesses the capacity for repair of wounds, which are dependent on the multiple types of stem cells in the skin. The most investigated stem cells of the skin are keratinocytes. These epidermal stem cells have been able to successfully treat patients with extensive burn wounds.

In practice, a biopsy of a healthy portion of the patient’s is made, and the keratinocytes it contains are grown on a feeder layer composed of cells called fibroblasts. A few weeks later, these stem cells give rise to continuous sheets of epidermis that can be transplanted back to the patient. Through cellular expansion, keratinocytes interact with the feeder layer and can undergo multiple fates: rest, symmetric division, asymmetric division, death and differentiation. Understanding the dynamics of keratinocytes regarding these features is important to improve skin transplantation techniques such as to incorporate hair follicles and natural mechanistic properties to the engineered skin. The goal of this project is to develop algorithms for identifying and tracking keratinocytes in co-culture- in the presence of other cells – in label-free phase contrast and/or digital holographic microscopy videos. The student will have to implement novel tracking approaches of cells whose shape and number vary over time. Then, we will develop analytic tools to obtain quantitative data: cell count, division time, death rate and more.