Cutaneous Immune Responses to Ablative Fractional Laser, Heat- and Cold-Based Dermatological Procedures

Area of Science:

• Dermatology and Immunology
• Cutaneous immune responses to physical modalities

Background:

• Dermatology frequently utilizes physical treatments like ablative fractional laser (AFL), electrocautery, and cryotherapy.
• Understanding the short-term immune reactions to these modalities is crucial for optimizing their clinical application.

Purpose of the Study:

• To compare the innate and adaptive immune responses induced by ablative fractional laser (AFL) versus heat- and cold-based dermatological procedures.
• To characterize the timing and nature of immune cell infiltration following these interventions.

Main Methods:

• Murine skin was subjected to AFL, monopolar electrocautery (RF), thermocautery, and cryotherapy, standardized to reach the reticular dermis.
• Innate (neutrophils) and adaptive (T cells) immune cell infiltration was assessed on Days 1 and 7 post-treatment via histology.
• Immune response in murine basal cell carcinomas (BCC) after AFL was also examined.

Main Results:

• AFL and heat-based procedures induced immediate innate immune responses (neutrophil infiltration) and increased CD45+ cells on Day 1.
• Cryotherapy elicited a delayed innate immune response, with increased neutrophils and CD45+ cells observed on Day 7.
• AFL demonstrated a significant increase in dermal T cells by Day 7 and enhanced CD8+ T cell infiltration in BCC tumors.

Conclusions:

• Heat-based procedures induce immediate cutaneous immune responses, whereas cryotherapy results in a delayed immune reaction.
• Ablative fractional laser (AFL) significantly boosts T cell responses in both normal skin and basal cell carcinoma tumors.
• AFL shows promise as an adjuvant therapy in the immunotherapeutic treatment of keratinocyte cancers.