Photothermal therapy enhanced the effectiveness of imiquimod against refractory cutaneous warts through boosting immune responses

Clinical guideline for the diagnosis and treatment of cutaneous warts (2022)

AIM

Cutaneous warts caused by human papillomavirus are benign proliferative lesions that occur at any ages in human lives. Updated, comprehensive and systematic evidence-based guidelines to guide clinical practice are urgently needed.

METHODS

We collaborated with multidisciplinary experts to formulate this guideline based on evidences of already published literature, focusing on 13 clinical questions elected by a panel of experts. We adopted Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to form classification of recommendations as well as the improved Delphi method to retain respective recommendations with a consensus degree of over 80%.

RESULTS

Our guideline covered aspects of the diagnosis and treatment of cutaneous warts such as diagnostic gold standard, transmission routes, laboratory tests, treatment principle, clinical cure criterion, definitions, and treatments of common warts, flat warts, plantar warts, condyloma acuminatum, and epidermodysplasia verruciformis. Recommendations about special population such as children and pregnant women are also listed. In total, 49 recommendations have been obtained.

CONCLUSIONS

It is a comprehensive and systematic evidence-based guideline and we hope this guideline could systematically and effectively guide the clinical practice of cutaneous warts and improve the overall levels of medical services.

Laser vaccine adjuvants: Light-augmented immune responses

Adjuvants are essential for ensuring the efficacy of modern vaccines. Considering frequent local and systemic adverse reactions, research into the development of safer and more effective adjuvants is being actively conducted. In recent years, the novel concept of laser vaccine adjuvants, which use the physical energy of light, has been developed. For long, light has been known to affect the physiological functions in living organisms. Since the development of lasers as stable light sources, laser adjuvants have evolved explosively in multiple ways over recent decades. Future laser adjuvants would have the potential not only to enhance the efficacy of conventional vaccine preparations but also to salvage candidate vaccines abandoned during development because of insufficient immunogenicity or owing to their inability to be combined with conventional adjuvants. Furthermore, the safety and efficacy of non-invasive laser adjuvants make them advantageous for vaccine dose sparing, which would be favorable for the timely and equitable global distribution of vaccines. In this review, we first describe the basics of light-tissue interactions, and then summarize the classification of lasers, the history of laser adjuvants, and the mechanisms by which different lasers elicit an immune response.

Transcriptomic analysis of mechanism of melanoma cell death induced by photothermal therapy

Melanoma is a malignancy with poor prognosis. Its incidence rate has been on the rise and it poses high health and economic challenges to different populations. Photothermal therapy (PTT) served as an effective local therapy in treating various tumors, particularly cutaneous carcinoma like melanoma. To fully understand the mechanisms of tumor cell death induced by PTT, we investigated gene expression and immune cells compositions of B16-F10 tumors after PTT treatment. A total of 256 differentially expressed genes (DEGs) were identified, with 215 being downregulated and 41 upregulated by PTT. Functional annotation showed that most DEGs involved in immune response and inflammatory response. Immune cells compositions inference revealed changes in many immune cells including regulatory T cells, M2 macrophage and B cells after PTT treatment. Our results help delineate the mechanism of cell death at the transcriptional level triggered by non-invasive PTT treatment of melanoma without exogenous light absorbing agents.

Hydrogen-Peroxide-Responsive Protein Biomimetic Nanoparticles for Photothermal-Photodynamic Combination Therapy of Melanoma

BACKGROUND AND OBJECTIVES

Recently, there has been a rapid increase in the incidences of melanoma, which represents a serious threat to human health. Generally, tumor-microenvironment-responsive nanoparticle-based photothermal-photodynamic combination therapy (PTT-PDT) is characterized by intratumoral response and tumor targeting. In this study, we designed and synthesized hydrogen-peroxide-responsive protein biomimetic nanoparticles (MnO₂ -ICG@BSA) for the treatment of melanoma.

STUDY DESIGN/MATERIALS AND METHODS

Briefly, MnO₂ -ICG@BSA was prepared using a mild protein synthesis method by loading indocyanine green (ICG) into a bovine serum albumin-manganese dioxide complex (MnO₂ @BSA); next, its characteristics were determined. In addition, in vitro biocompatibility and antitumor efficacy were assessed using the classic cell counting kit-8 assay. Moreover, in vivo high-frequency ultrasound and thermal imaging were used to evaluate the oxygen-production capacity and photothermal conversion effect of MnO₂ -ICG@BSA at the tumor site, and Singlet Oxygen Sensor Green (SOSG) was used to measure singlet oxygen levels in the tumor. The antitumor efficacy was assessed based on relative tumor size, bodyweight, survival curves, and hematoxylin and eosin staining.

RESULTS

The results showed that MnO₂ -ICG@BSA has a high photothermal conversion efficiency, a strong singlet oxygen-generation ability, and high photothermal stability. In addition, in vitro PTT-PDT experiments showed that MnO₂ -ICG@BSA has a significant inhibitory effect on the proliferation of B16F10 melanoma cells. Meanwhile, in vivo experiments showed that MnO₂ -ICG@BSA has a significant inhibitory effect on melanoma in mice. Preliminary toxicity studies indicated that MnO₂ -ICG@BSA exhibits low toxicity.

CONCLUSION

From the results, we can conclude that MnO₂ -ICG@BSA could be used in PTT-PDT to treat melanoma, making it a good candidate material for PTT-PDT. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Laser adjuvant for vaccination

The use of an immunologic adjuvant to augment the immune response is essential for modern vaccines which are relatively ineffective on their own. In the past decade, researchers have been consistently reporting that skin treatment with a physical parameter, namely laser light, augments the immune response to vaccine and functions as an immunologic adjuvant. This "laser adjuvant" has numerous advantages over the conventional chemical or biological agents; it is free from cold chain storage, hypodermic needles, biohazardous sharp waste, irreversible formulation with vaccine antigen, undesirable biodistribution in vital organs, or unknown long-term toxicity. Since vaccine formulations are given to healthy populations, these characteristics render the "laser adjuvant" significant advantages for clinical use and open a new developmental path for a safe and effective vaccine. In addition, laser technology has been used in the clinic for more than three decades and is therefore technically matured and has been proved to be safe. Currently, four classes of laser adjuvant have been reported; ultrashort pulsed, non-pulsed, non-ablative fractional, and ablative fractional lasers. Since each class of the laser adjuvant shows a distinct mechanism of action, a proper choice is necessary to craft an effective vaccine formulation toward a desired clinical benefit for a clinical vaccine to maximize protection. In addition, data also suggest that further improvement in the efficacy is possible when a laser adjuvant is combined with chemical or biological adjuvant(s). To realize these goals, further efforts to uncover the molecular mechanisms of action of the laser adjuvants is warranted. This review provides a summary and comments of the recent updates in the laser adjuvant technology.