Related Experiment Video
Updated: Feb 5, 2026
04:53
An In Vitro Approach to Photodynamic Therapy
Published on: August 17, 2018
9.4K
An In Vitro Approach to Photodynamic Therapy
1Department of Dermatology, University of California, Davis; Dermatology Service, Sacramento VA Medical Center; evanaustin1500@gmail.com.
Journal of Visualized Experiments : Jove
|September 4, 2018
Summary
Photodynamic therapy (PDT) effectively induces cancer cell apoptosis using a photosensitizer (PS) and light. This study details an in vitro method to optimize PDT protocols for novel applications.
Area of Science:
- Biomedical Engineering
- Photochemistry
- Cell Biology
Background:
- Photodynamic therapy (PDT) utilizes photosensitizers (PS) and light to induce cell apoptosis, approved for actinic keratosis and recommended for skin cancers.
- PDT offers a low-cost, non-invasive treatment with minimal side effects, promoting cell apoptosis via reactive oxygen species.
- Established PDT protocols are crucial for studying novel PSs, optimizing treatment parameters, and exploring new clinical indications.
Purpose of the Study:
- To establish a reproducible in vitro method for studying photodynamic therapy (PDT) in adherent cell lines.
- To investigate the dose-dependent effect of 5-aminolevulinic acid (5-ALA) on squamous cell carcinoma apoptosis.
- To provide a framework for optimizing PDT parameters like incubation time, temperature, and light wavelengths.
Main Methods:
- Squamous cell carcinoma cells were incubated with varying concentrations of 5-aminolevulinic acid (5-ALA) (0-2 mM) for 30 minutes.
- Cells were photoactivated using 417 nm blue light for 1,000 seconds.
- Apoptosis and necrosis were quantified using annexin-V and 7-aminoactinomycin D flow cytometry.
Main Results:
- A dose-dependent increase in cell apoptosis was observed following 5-ALA incubation.
- Consistent incubation and light parameters are critical for inter-test validity in in vitro PDT studies.
- The developed protocol simulates clinical PDT and can be adapted for various cell lines and PSs.
Conclusions:
- In vitro PDT research facilitates the development of new photosensitizers (PSs) and treatment protocols.
- This method provides a foundation for optimizing PDT parameters and exploring new therapeutic indications.
- Consistent experimental conditions are essential for reliable in vitro photodynamic therapy research.
Related Concept Videos
00:59Gene Therapy
27.6K
Gene therapy is a technique where a gene is inserted into a person’s cells to prevent or treat a serious disease. The added gene may be a healthy version of the gene that is mutated in the patient, or it could be a different gene that inactivates or compensates for the patient’s disease-causing gene. For example, in patients with severe combined immunodeficiency (SCID) due to a mutation in the gene for the enzyme adenosine deaminase, a functioning version of the gene can be...
27.6K
01:26Group Therapy
450
Group therapy is a sociocultural approach to psychological treatment, where individuals with shared psychological challenges come together under the guidance of a mental health professional. This therapeutic modality offers unique opportunities for individuals to connect, share, and grow within the context of a supportive group. By fostering mutual understanding and collaboration, group therapy can address a range of psychological concerns effectively, often complementing or surpassing the...
450
01:20Frustration and Conflict: Approach-Approach, Approach-Avoidance
539
Frustration occurs when people are obstructed or prevented from achieving a desired goal or fulfilling a perceived need. For example, when someone's input is ignored in a discussion, it can lead to feelings of frustration. Conflict, however, arises from opposing interests, goals, or actions. Conflicts can take various forms based on the nature of these opposing desires or goals.
One common type of conflict is the Approach–Approach Conflict. In this case, a person faces two desirable...
One common type of conflict is the Approach–Approach Conflict. In this case, a person faces two desirable...
539
02:49Cancer Therapies
10.2K
Cancer therapies are various modes of treatment, such as surgery, radiation therapy, and chemotherapy that are administered to cancer patients.
However, cancer treatments can pose several challenges, as therapies used to kill cancer cells are generally also toxic to normal cells. Moreover, cancer cells mutate rapidly and can develop resistance to chemical agents or radiation therapy. Besides, all types of cancer cells may not respond to the same therapy. Some cancer cells respond to one...
However, cancer treatments can pose several challenges, as therapies used to kill cancer cells are generally also toxic to normal cells. Moreover, cancer cells mutate rapidly and can develop resistance to chemical agents or radiation therapy. Besides, all types of cancer cells may not respond to the same therapy. Some cancer cells respond to one...
10.2K
01:22Behavior Therapy
725
Behavior therapy incorporates diverse techniques rooted in classical conditioning principles to address maladaptive behaviors and anxiety disorders. These methods aim to reduce avoidance behaviors, foster adaptive coping mechanisms, and alter associations between stimuli and responses, making them effective in a wide range of therapeutic contexts.
Exposure therapy is a cornerstone of behavioral treatment for anxiety disorders. It involves systematic exposure to feared stimuli, either in real...
Exposure therapy is a cornerstone of behavioral treatment for anxiety disorders. It involves systematic exposure to feared stimuli, either in real...
725
01:28Drug Therapy
301
The advent of drug therapy has profoundly shaped modern mental health care, providing targeted treatments for a range of psychological disorders. Psychotherapeutic drugs, classified into antianxiety, antidepressant, and antipsychotic medications, address symptoms across anxiety disorders, mood disorders, and schizophrenia. While these medications have transformed patient outcomes, they require careful management due to their potential side effects and limitations.
Antianxiety Medications
Antianxiety Medications
301