Photodynamic Therapy for Genital Warts Causes Activation of Local Immunity

5-aminolevulinic acid induced photodynamic reactions in diagnosis and therapy for female lower genital tract diseases

Since the patients suffering from female lower genital tract diseases are getting younger and younger and the human papilloma virus (HPV) infection is becoming more widespread, the novel non-invasive precise modalities of diagnosis and therapy are required to remain structures of the organ and tissue, and fertility as well, by which the less damage to normal tissue and fewer adverse effects are able to be achieved. In all nucleated mammalian cells, 5-Aminolevulinic acid (5-ALA) is an amino acid that occurs spontaneously, which further synthesizes in the heme biosynthetic pathway into protoporphyrin IX (PpIX) as a porphyrin precursor and photosensitizing agent. Exogenous 5-ALA avoids the rate-limiting step in the process, causing PpIX buildup in tumor tissues. This tumor-selective PpIX distribution after 5-ALA application has been used successfully for tumor photodynamic diagnosis (PDD) and photodynamic therapy (PDT). Several ALA-based drugs have been used for ALA-PDD and ALA-PDT in treating many (pre)cancerous diseases, including the female lower genital tract diseases, yet the ALA-induced fluorescent theranostics is needed to be explored further. In this paper, we are going to review the studies of the mechanisms and applications mainly on ALA-mediated photodynamic reactions and its effectiveness in treating female lower genital tract diseases.

Evaluation of combination of ALA-PDT and interferon for cervical low-grade squamous intraepithelial lesion (LSIL)

BACKGROUND

Cervical LSIL is a precancerous disease which requires regular follow-up. High risk patients need active interventions. Interferon and topical PDT have been used in the treatment of cervical LSIL. The aim of this study was to evaluate the combination use of topical PDT and interferon in the treatment of cervical LSIL.

MATERIALS AND METHODS

A prospective study was carried out involving 159 women with cervical LSIL and high risk human papillomaviruses (hr-HPV) infection. Patients were divided into three groups. Group 1-receiving interferon suppository only, Group 2-receiving 19 mg/cm2 ALA plus post PDT interferon, and Group 3-receiving 38 mg/cm2 ALA plus post PDT interferon. The primary endpoint was pathological regression. The secondary endpoints were the HPV negative conversion rate and the adverse effects of treatment.

RESULTS

At 6-12 months after PDT, for Group 1, the effective rate, CR rate and HPV negative conversion rate was 48.3 %, 43.3 % and 24.0 %, respectively. For Group 2, the effective rate, CR rate and HPV negative conversion rate were 89.3 %, 71.4 %, and 72.4 %, respectively. For Group 3, the effective rate, CR rate and HPV negative conversion rate were 91.5 %, 66.1 %, and 64.4 %, respectively, significantly higher than those of interferon only group. Two ALA dose group study showed similar efficacy. No patient experienced serious adverse effects.

CONCLUSIONS

ALA-PDT combined with interferon therapy was feasible and tolerable. Two ALA dose groups showed similar outcomes in treating cervical LSIL.

Photodynamic therapy in periodontitis: A narrative review

BACKGROUND

Periodontitis, a chronic infectious disease, is primarily caused by a dysbiotic microbiome, leading to the destruction of tooth-supporting tissues and tooth loss. Photodynamic therapy (PDT), which combines excitation light with photosensitizers (PS) and oxygen to produce antibacterial reactive oxygen species, is emerging as a promising adjuvant treatment for periodontitis.

METHODS

This review focuses on studies examining the antibacterial effects of PDT against periodontal pathogens. It also explores the impact of PDT on various aspects of periodontal health, including periodontal immune cells, human gingival fibroblasts, gingival collagen, inflammatory mediators, cytokines in the periodontium, vascular oxidative stress, vascular behavior, and alveolar bone health. Clinical trials assessing the types of PSs and light sources used in PDT, as well as its effects on clinical and immune factors in gingival sulcus fluid and the bacterial composition of dental plaque, are discussed.

RESULTS

The findings indicate that PDT is effective in reducing periodontal pathogens and improving markers of periodontal health. It has shown positive impacts on periodontal immune response, tissue integrity, and alveolar bone preservation. Clinical trials have demonstrated improvements in periodontal health and alterations in the microbial composition of dental plaque when PDT is used alongside conventional treatments.

CONCLUSIONS

PDT offers a promising adjunctive treatment for periodontitis, with benefits in bacterial reduction, tissue healing, and immune modulation. This article highlights the potential of PDT in periodontal therapy and emphasizes the need for further research to refine its clinical application and efficacy.

A novel PDT: 5-aminolevulinic acid combined 450 nm blue laser photodynamic therapy significantly promotes cell death of HR-HPV infected cells

Human papillomavirus (HPV) infection and related diseases are clinical challenges. The efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) using red laser (630 ± 5 nm) is remarkable and safe. In this study, we aim to investigate the efficacy of ALA-450 nm PDT comparing with ALA-635 nm PDT. We detected cell proliferation and cell apoptosis through MTT assay and flow cytometry assay respectively. Flow cytometry assay determined the intracellular reactive oxygen species (ROS) generation. Western blotting analysis investigated the protein expression. In vivo, immunohistochemical staining assay and TUNEL assay were performer to detect cell apoptosis. ALA-450 nm PDT inhibited the proliferation of End1 and HeLa cells, promoted cell apoptosis more effectively than ALA-635 nm PDT, and induced cell death probably through increasing the intracellular ROS generation and caspase-dependent apoptosis pathway. In vivo, ALA-450 nm PDT significantly inhibited tumour growth and activated cell apoptosis. The ALA-450 nm PDT had an advantage over ALA-635 nm PDT on inhibiting the proliferation of End1 and HeLa cells and inducing cell apoptosis. The ALA-450 nm PDT might be a promising therapeutic strategy for eradicating the HR-HPV infected cells and promoting the integration of diagnosis and treatment of HR-HPV related diseases.HighlightsWe combined 5-aminolevulinic acid with 450 nm blue laser using as a novel type of photodynamic therapy.The ALA-450 nm PDT had an advantage over ALA-635 nm PDT on inhibition of the proliferation of End1 and HeLa cells and inducing cell apoptosis in vitro and in vivo.The ALA-450 nm PDT may provide a novel alternative therapeutic option in patients with persistent HPV infection and promote the integration of diagnosis and treatment.

Photodynamic therapy for intergluteal warts in a child affected by Rett syndrome

Genital warts (GWs) are the most common sexually transmitted infections worldwide, caused by the human papillomavirus (HPV). The increasing prevalence of GWs in children has renewed the interest in therapeutic management which still presents a unique challenge, being influenced by many variables including size, quantity, and location of warts, as well as the presence of comorbidities. Conventional photodynamic therapy (C-PDT) has already shown encouraging results in the treatment of viral warts in adult patients, but its use is still not standardized in the pediatric population. On this topic, we report our experience with C-PDT in a difficult-to-treat area like the perianal region in a 12-year-old girl affected by Rett syndrome, an X-linked dominant neurological disorder, with a 10-month history of florid genital condylomatosis. After the third session of C-PDT, complete clearance of the lesions was achieved. Our case is paradigmatic of the potentiality of PDT to treat difficult lesions in difficult patients. Despite being expensive and time-consuming, this procedure has been demonstrated to be safe and well-tolerated. Lastly, the therapy is also well accepted by parents, due to its minimal invasiveness and the few side effects, compared to the other therapeutic options.

Peripheral blood CD4+ T cell count predicts recurrence of condyloma acuminatum after photodynamic therapy in HIV-positive patients

BACKGROUND

Few studies have reported postoperative relapse of condyloma acuminatum (CA) after 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in human immunodeficiency virus (HIV) positive patients.

METHODS

The clinical data of HIV-positive CA patients treated with ALA-PDT from October 2018 to December 2019 were analyzed retrospectively. Univariate and multivariate Cox regression was used to analyze the variables related to postoperative recurrence. Pearson correlation test was employed to analyze the correlation between CD4⁺ T cell count and postoperative recurrence rate. Kaplan-Meier method was used to compare the CA recurrence after ALA-PDT in low CD4 group and high CD4 group.

RESULTS

A total of 38 HIV-positive patients with CA were included in the study. Among them, 26 patients experienced CA recurrence within 6 months, and the recurrence rate was 68.4%. CD4⁺ T cell count was 187.0 (79.0-596.0) cells/μl in relapsed patients and 406.0 (89.0-612.0) cells/μl in non-relapsed patients, showing a statistically significant difference (p = .005). Pearson correlation coefficient analysis revealed a negative correlation between CD4⁺ T cell count and postoperative recurrence rate (p = .005, r = -.443). Univariate regression analysis showed that CD4⁺ T cell count was correlated with postoperative recurrence, hazard ratio (HR) was 0.99 [95% Confidence interval (CI) = 0.99-1.0, p = .012]. Multivariate Cox regression analysis showed that with the low CD4⁺ T cell count as the reference, the high CD4⁺ T cell count was negatively correlated with postoperative recurrence (HR = 0.09, 95% CI 0.01-0.87, p = .038).

CONCLUSIONS

Peripheral blood CD4⁺ T cell count can predict the CA recurrence rate after ALA-PDT in HIV-positive patients.

Photodynamic therapy in the treatment of condyloma acuminata: A systematic review of clinical trials

INTRODUCTION

Condylomata acuminata (CA) is a sexually transmitted infection with a high prevalence associated with psychosexual morbidity in both men and women of various age. Up to now, treatment modalities yield low clearance and recurrence rate (RR) and are also deemed low quality evidence-wise. Photodynamic therapy (PDT) is a novel and promising therapy to effectively cure and prevent CA recurrence.

METHOD

This systematic review was reported according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) and registered to the International Prospective Register of Systematic Review (PROSPERO) (CRD42022332760).

RESULTS

Ten studies were included in this systematic review. A significant value of complete response (CR) ranging from 63-100% in patients with genital warts after receiving several sessions of PDT. A relatively low recurrence rate was seen in all 10 studies, with an RR of less than 17%. Quality assessment of included studies reported mostly high-quality research.

CONCLUSIONS

PDT therapy resulted in a higher CR with significantly lower RR compared to other therapies. Thus, PDT can be an alternative treatment of CA with low RR and minimal side effects. Additional research, especially randomized clinical trials in various countries, is needed to further substantiate this treatment and formulate definitive protocols.

Photodynamic therapy-a promising treatment of oral mucosal infections

The treatment of oral mucosal infections is increasingly challenging owing to antibiotic resistance. Therefore, alternative antimicrobial strategies are urgently required. Photodynamic therapy (PDT) has attracted attention for the treatment of oral mucosal infections because of its ability to effectively inactivate drug-resistant bacteria, completely heal clinical infectious lesions and usually offers only mild adverse reactions. This review briefly summarizes relevant scientific data and published papers and discusses the potential mechanism and application of PDT in the treatment of oral mucosal infections.

Comprehensive literature review of the applications of surgical laser in benign anal conditions

Surgery for benign anal conditions is a common practice and is usually followed by a good outcome. The present review aimed to summarize the emergence and evolution of different laser techniques used for the treatment of benign anal conditions and report their current outcome. PubMed and Scopus were searched for studies that assessed the use of laser in benign anal conditions. Anal conditions reviewed were hemorrhoids, anal fistula, anal warts, anal stenosis, and anal fissure. The full text of the studies retrieved was summarized in a narrative and tabular form. Laser techniques used for the treatment of hemorrhoidal disease were laser open hemorrhoidectomy, laser hemorrhoidoplasty, and Doppler-guided hemorrhoidal laser dearterialization. Resolution of hemorrhoidal symptoms was reported in 72-100% of patients after laser treatment. YAG laser, fistula laser closure, and photodynamic therapy have been used for the treatment of anal fistula with success rates ranging from 20 to 92.6%. Anal warts can be treated with photodynamic therapy with or without YAG or CO² laser with a success rate up to 88%. A few studies reported the use of laser in the treatment of chronic anal fissure and anal stenosis. The use of laser in the treatment of benign anal conditions is associated with promising outcomes. Laser was most assessed in hemorrhoidal disease and anal fistula and showed more consistent success rates with hemorrhoidal disease than with anal fistula. Preliminary reports assessed the outcome of laser treatment in other conditions as anal fissure and warts with acceptable outcomes.

TLR9 in the Human Papilloma Virus Infections: Friend or Foe?

Immune system plays dual roles during human papilloma virus (HPV) infections, from defense against the virus to induction or stimulation of the HPV-related cancers. It appears that various differences within the immune-related genes and the functions of the immunological parameters of the patients are the main factors responsible for the roles played by immune system during HPV infections. Toll-like receptors (TLRs) play key roles in the recognition of viruses and activation of immune responses. The molecules also can alter the target cell intracellular signaling and may participate in the transformation of the infected cells. TLR9 is the unique intracellular member of TLRs that recognize foreign DNA, including viral DNA. Thus, TLR9 may play significant roles in the defense against HPV and its related cancers. This review article discusses TLR9 antiviral and pathological roles during HPV infection.

Antimicrobial Photodynamic Therapy Involving a Novel Photosensitizer Combined With an Antibiotic in the Treatment of Rabbit Tibial Osteomyelitis Caused by Drug-Resistant Bacteria

Osteomyelitis is deep tissue inflammation caused by bacterial infection. If such an infection persists, it can lead to dissolution and necrosis of the bone tissue. As a result of the extensive use of antibiotics, drug-resistant bacteria are an increasingly common cause of osteomyelitis, limiting the treatment options available to surgeons. Photodynamic antibacterial chemotherapy has attracted increasing attention as a potential alternative treatment. Its advantages are a broad antibacterial spectrum, lack of drug resistance, and lack of toxic side effects. In this study, we explored the impact of the new photosensitizer LD4 in photodynamic antimicrobial chemotherapy (PACT), both alone and in combination with an antibiotic, on osteomyelitis. A rabbit tibial osteomyelitis model was employed and microbiological, histological, and radiological studies were performed. New Zealand white rabbits (n = 36) were randomly divided into a control group, antibiotic group, PACT group and PACT + antibiotic group for treatment. In microbiological analysis, a reduction in bacterial numbers of more than 99.9% was recorded in the PACT group and the PACT + antibiotic group 5 weeks after treatment (p < 0.01). In histological analysis, repair of the damaged bone tissue was observed in the PACT group, and bone repair in the PACT + antibiotic group was even more significant. In radiological analysis, the X-ray Norden score showed that the severity of bone tissue defects or destruction followed the pattern: PACT + antibiotic group < PACT group < antibiotic group < control group.

ALA-PDT successfully treated Majocchi's granuloma by directly killing Trichophyton tonsurans and recruiting T lymphocytes

BACKGROUND

Majocchi's granuloma (MG) is a deep persistent suppurative granulomatous perifolliculitis which might be caused by Trichophyton tonsurans (T. tonsurans). Conventional treatment for MG is oral administration of systematic antifungal drugs, associated with a low cure rate and a high relapse rate. ALA-PDT is a new approach for fungal infection.

METHODS

A case of refractory MG was treated by 3 times of ALA-PDT. At the same time, T. tonsurans strains isolated from the lesions of the patient were used for an in vitro inhibition experiment and an in vivo experiment in guinea pig model to furtherly verify the effectiveness and investigate the mechanism of ALA-PDT for T. tonsurans.

RESULTS

After 3 times of ALA-PDT, the lesions of MG were eliminated. And the mycological and pathological examination showed a disappearance of fungi in follicles. In vitro and in vivo experiment both demonstrated that ALA-PDT could obviously inhibit the growth of T. tonsurans partly by directly destroying the structure of fungal cells and recruiting CD4 + T cells.

CONCLUSION

ALA-PDT is a potentially effective noninvasive method for the treatment of MG with mechanisms of direct killing and with CD4⁺ T cell-mediated immune response.

Successful management of giant condyloma acuminatum of vulva with the combination of surgery and photodynamic therapy: Report of two cases

Patients with condylomata acuminata of the vulva usually have increased difficulty to achieve complete response to treatment and also have a higher risk for disease recurrence. Treatment for this disease varies, including surgical excision, cryotherapy, electrocautery, CO2 laser therapy, topical therapy, and photodynamic therapy (PDT), but none of these alone provides a satisfactory outcome, especially for giant condyloma acuminatum (GCA). We reported two cases of GCA successfully cured with surgical removal, electrocautery and photodynamic therapy.

Efficacy and safety of conventional versus daylight photodynamic therapy in children affected by multiple facial flat warts

BACKGROUND

facial flat warts (FFWs) are a superficial viral skin disease, extremely common in childhood. Recently, conventional photodynamic therapy (C-PDT) has been used for the treatment of FFWs with good outcome. The efficacy of daylight photodynamic therapy (DL-PDT) has not yet been evaluated.

OBJECTIVES

to investigate and assess the efficacy and safety of C-PDT versus DL-PDT using 10% aminolevulinic acid (ALA) in the treatment of recalcitrant FFWs in a paediatric setting.

MATERIALS AND METHODS

30 consecutive patients aged <18 years with FFWs of the face were included and randomly divided into two groups: group A (15 patients) was treated with C-PDT and group B (15 patients) with DL-PDT. Patients underwent treatments for three times with 1-month intervals. The response was assessed on week 4,812 and 24 (T4,T8,T12,T24) and scored as excellent (75-100% reduction of total wart count), very good (74-50% reduction), good (49-25% reduction), poor (<25% reduction or no response). Any adverse event occurring during/after ALA application/irradiation as well as pain intensity were recorded at each visit.

RESULTS

at T4 and T8 no excellent response was achieved in both groups. At week 12, excellent response was observed in 53.3% of group A patients vs 0% of group B patients, although in the latter 66.7% of patients achieved a very good response. Excellent outcome raised to 73.3% and 80% in group A and B, respectively, at week 24. Poor response to therapy was observed in 26.7% of patients in group A and 20% in group B. Both treatment modalities were well tolerated, with transient pain, irritation and hyperpigmentation as main side effects.

CONCLUSIONS

ALA-PDT is effective and safe for FFWs, with striking cosmetic results and no recurrence. Compared with conventional modality, DL-PDT is better tolerated, time-saving, nearly painless and greatly appreciated by young patients.

DNA Strand Break Properties of Protoporphyrin IX by X-Ray Irradiation against Melanoma

Recent reports have suggested that 5-aminolevulinic acid (5-ALA), which is a precursor to protoporphyrin IX (PpIX), leads to selective accumulation of PpIX in tumor cells and acts as a radiation sensitizer in vitro and in vivo in mouse models of melanoma, glioma, and colon cancer. In this study, we investigated the effect of PpIX under X-ray irradiation through ROS generation and DNA damage. ROS generation by the interaction between PpIX and X-ray was evaluated by two kinds of probes, 3′-(p-aminophenyl) fluorescein (APF) for hydroxyl radical (•OH) detection and dihydroethidium (DHE) for superoxide (O₂^•-). •OH showed an increase, regardless of the dissolved oxygen. Meanwhile, the increase in O₂^•- was proportional to the dissolved oxygen. Strand breaks (SBs) of DNA molecule were evaluated by gel electrophoresis, and the enhancement of SBs was observed by PpIX treatment. We also studied the effect of PpIX for DNA damage in cells by X-ray irradiation using a B16 melanoma culture. X-ray irradiation induced γH2AX, DNA double-strand breaks (DSBs) in the context of chromatin, and affected cell survival. Since PpIX can enhance ROS generation even in a hypoxic state and induce DNA damage, combined radiotherapy treatment with 5-ALA is expected to improve therapeutic efficacy for radioresistant tumors.

A New Treatment Opportunity for DIPG and Diffuse Midline Gliomas: 5-ALA Augmented Irradiation, the 5aai Regimen

Prognosis for diffuse intrinsic pontine glioma (DIPG) and generally for diffuse midline gliomas (DMG) has only marginally improved over the last ~40 years despite dozens of chemotherapy and other therapeutic trials. The prognosis remains invariably fatal. We present here the rationale for a planned study of adding 5-aminolevulinic acid (5-ALA) to the current irradiation of DIPG or DMG: the 5aai regimen. In a series of recent papers, oral 5-ALA was shown to enhance standard therapeutic ionizing irradiation. 5-ALA is currently used in glioblastoma surgery to enable demarcation of overt tumor margins by virtue of selective uptake of 5-ALA by neoplastic cells and selective conversion to protoporphyrin IX (PpIX), which fluoresces after excitation by 410 nm (blue) light. 5-ALA is also useful in treating glioblastomas by virtue of PpIX's transfer of energy to O₂ molecules, producing a singlet oxygen that in turn oxidizes intracellular DNA, lipids, and proteins, resulting in selective malignant cell cytotoxicity. This is called photodynamic treatment (PDT). Shallow penetration of light required for PpIX excitation and resultant energy transfer to O₂ and cytotoxicity results in the inaccessibility of central structures like the pons or thalamus to sufficient light. The recent demonstration that keV and MeV photons can also excite PpIX and generate singlet O₂ allows for reconsideration of 5-ALA PDT for treating DMG and DIPG. 5-ALA has an eminently benign side effect profile in adults and children. A pilot study in DIPG/DMG of slow uptitration of 5-ALA prior to each standard irradiation session-the 5aai regimen-is warranted.