Clinical Trial Details
— Status: Active, not recruiting
Administrative data
NCT number |
NCT05020496 |
Other study ID # |
300007159 |
Secondary ID |
|
Status |
Active, not recruiting |
Phase |
Early Phase 1
|
First received |
|
Last updated |
|
Start date |
March 21, 2022 |
Est. completion date |
October 1, 2026 |
Study information
Verified date |
June 2024 |
Source |
University of Alabama at Birmingham |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The overall goal of this study is to determine novel mechanisms for ultraviolet light
(UV)-induced suppression of the immune system in human subjects and to improve understanding
of UV-induced skin carcinogenesis.
Description:
Sunlight is the major environmental agent to which the skin is exposed. Injudicious exposure
to wavelengths in the ultraviolet spectrum can lead to sunburn, aging of the skin, skin
cancer and a variety of photosensitivity diseases, many of which have an immunologic
pathogenesis. American Cancer Society acknowledges that most skin cancers are a direct result
of exposure to the ultraviolet (UV) rays in sunlight. Skin cancer has also been linked to
exposure to some artificial sources of UV rays (indoor tanning, welding and metal work, and
phototherapy). UV, in addition to producing mutant cells, also impairs host cell-mediated
immune responses that have evolved to identify and eradicate the mutant cells before they
develop into clinically apparent malignancies. In fact, organ transplant recipients who are
treated with immunosuppressive medications have a greatly increased risk (up to 100 times) of
UV induced skin cancers and the tumors that do develop behave more aggressively. Triggering
receptor expressed on myeloid cells (Trem)-1 is highly expressed by myeloid cells in human
infectious and inflammatory diseases and is associated with poor prognosis of cancer
patients. However, most studies have focused on Trem1 mediated effects on innate immune cells
such as neutrophils in inflammatory reactions. Little is known about whether and how Trem1
regulates the adaptive immunity, especially the activity of antigen presenting cells (APC) to
regulate the activation and function of antigen specific T cells. Our study will demonstrate
a novel mechanism for Trem1 signaling in T cell mediated immune responses and
photocarcinogenesis in skin. Different biological parameters in UV exposed skin tissues will
be analyzed, which are crucial for UV-induced DNA damage, erythema, and immune suppressive
effects that have been directly associated with photoimmunology and implicated in the risk of
skin cancer. These will correlated with the responsiveness of allergen induced contact
hypersensitivity.
Participants will be stratified based on gender and then randomly assigned to: 1) Control 2)
Non-UVB, or 3) UVB groups. The primary endpoint for the study will be the CHS evaluation on
day 34.The Control group no DPCP (Group 1) will serve as a negative control while the UVB &
diphenylcyclopropenone (DPCP) group (Group 2) will serves as a positive control for
measurement of response to irritant (contact hypersensitivity = CHS). Subjects in the UVB,
DPCP, and Biopsy group (Group 3), who have no more than one standard deviation above the mean
of CHS from the negative Control group, will be considered as Non-responders.