Using laser technology to boost immunotherapy for skin cancer: Rikke Christensen defends her PhD

Rikke Louise Christensen initiated her research at the Dermatology Department at Bispebjerg Hospital in 2020 and furthered her studies through a 7-month research stay at Associate Professor Shawn Demehris laboratory at Massachusetts General Hospital in Boston in 2022. Rikke is also the first student to complete a SCIN CAG PhD. Her research primarily focuses on evaluating the effectiveness of ablative fractional laser (AFL) in delivering PD-1 inhibitors locally and studying the cutaneous biodistribution after laser treatment. Furthermore, exploring AFL as adjuvant to systemic anti-PD-1 therapy by assessing the tumor response. 

The first part of her thesis examined the efficacy of AFL in delivering PD-1 inhibitors into the skin. The results demonstrated that the laser effectively facilitated the penetration of the drug, particularly in the middle layer of the skin. Additionally, the study revealed  the best outcome when using higher density setting and that the PD-1 inhibitor accumulated in a time dependent manner.

In addition, the drug delivery study investigated the PD-1 inhibitor’s biodistribution throughout the skin after laser treatment. The research showed that AFL led to a homogenous uptake that distributed in horizontal band-shaped pattern, whereas injecting the PD-1 inhibitors directly into the skin resulted in a focal  deep deposition that decreased over time. In second part of her thesis testing the combination of AFL and anti-PD1 therapy, the combined treatment resulted in a higher clearance rate of tumors compared to using either anti-PD-1 therapy or laser alone.

The findings of Rikke Louise Christensen's research suggest that the use of AFL in combination with PD-1 inhibitors could enhance the effectiveness of skin cancer treatment. Not only does the laser assist in delivering the PD-1 inhibitor locally, but it also appears to possess its own anti-cancer properties that can boost PD-inhibitor treatment. This discovery holds potential for more personalized and effective treatment approaches for skin cancer patients.

Principal supervisor: Prof. Merete Hædersdal, MD, PhD, DMSc

Primary supervisor: Uffe Høgh Olesen, MSc, PhD

Co-supervisors: Prof. Søren Husted, MSc, PhD and Silje Haukali Omland, MD, PhD