Ignite Creation Date:
2025-12-25 @ 3:31 AM
Ignite Modification Date:
2025-12-26 @ 2:13 AM
Study NCT ID:
NCT04350905
Status:
COMPLETED
Last Update Posted:
2022-04-12
First Post:
2020-04-16
Is NOT Gene Therapy:
False
Has Adverse Events:
True
Brief Title:
Characterization of Skin Immunity to Aedes Aegypti Saliva in Dengue-endemic Participants in Cambodia
Sponsor:
National Institute of Allergy and Infectious Diseases (NIAID)
Organization:
Study Overview
Official Title:
Characterization of Skin Immunity to Aedes Aegypti Saliva in Dengue-Endemic Participants in Cambodia
Status:
COMPLETED
Status Verified Date:
2021-04-09
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
Background:
Mosquito-borne viruses like dengue cause major illness and death worldwide, particularly in Southeast Asia. When mosquitoes deliver a virus into the skin of humans, they also leave saliva. Researchers want to learn more about skin immunity to mosquito saliva. They hope this will help with future vaccines and treatments for these diseases.
Objective:
To compare the early and late innate immune response in the skin of Aedes aegypti bitten versus unbitten skin.
Eligibility:
Healthy people ages 18-45 who live within about 15 km of the study site in Chbar Mon
Design:
Participants will have 3 visits.
The baseline/screening visit will include:
Medical and medication history
Questions about participants demographic information, mosquito biting risk factors, and responses to mosquito or other insect bites
Physical exam
Urine sample for some participants
Mosquito feeding. A feeding device will be placed on the participant s arm for up to 20 minutes. The insects will feed through a mesh on the bottom of the feeding device. Participants may be given standard treatments for any skin reactions.
Blood tests
Four skin biopsies taken from bitten and unbitten skin. Local anesthetic will be administered, and a small tool will be used to remove the participant s skin.
Participants will have a second visit the next day. They will have a physical exam and blood tests. They will have 1 skin biopsy.
Participants will have a final visit about 2 weeks later. They will have a physical exam and blood tests.
During the study, participants will be asked to take measures to prevent more mosquito bites.
Mosquito-borne viruses like dengue cause major illness and death worldwide, particularly in Southeast Asia. When mosquitoes deliver a virus into the skin of humans, they also leave saliva. Researchers want to learn more about skin immunity to mosquito saliva. They hope this will help with future vaccines and treatments for these diseases.
Objective:
To compare the early and late innate immune response in the skin of Aedes aegypti bitten versus unbitten skin.
Eligibility:
Healthy people ages 18-45 who live within about 15 km of the study site in Chbar Mon
Design:
Participants will have 3 visits.
The baseline/screening visit will include:
Medical and medication history
Questions about participants demographic information, mosquito biting risk factors, and responses to mosquito or other insect bites
Physical exam
Urine sample for some participants
Mosquito feeding. A feeding device will be placed on the participant s arm for up to 20 minutes. The insects will feed through a mesh on the bottom of the feeding device. Participants may be given standard treatments for any skin reactions.
Blood tests
Four skin biopsies taken from bitten and unbitten skin. Local anesthetic will be administered, and a small tool will be used to remove the participant s skin.
Participants will have a second visit the next day. They will have a physical exam and blood tests. They will have 1 skin biopsy.
Participants will have a final visit about 2 weeks later. They will have a physical exam and blood tests.
During the study, participants will be asked to take measures to prevent more mosquito bites.
Detailed Description:
Mosquito-borne viruses continue to cause significant global morbidity and mortality, particularly in Southeast Asia. When mosquitoes deliver the virus into the skin of humans while probing for a blood meal, they deposit also saliva, which contains a myriad of pharmacologically active compounds that modulate the host immune system. Little is known about skin immunity to mosquito saliva, particularly in endemic volunteers as most clinical studies are performed in na(SqrRoot) ve individuals who have never or rarely been exposed to a particular mosquito vector. People living in endemic areas have had long-term repeated exposure to these vectors and therefore have different immune response to mosquito saliva, which could interfere with mosquito-borne disease vaccine effectiveness. Characterization of skin immunity via various technical modalities will be important in order to identify critical aspects of the innate and adaptive immune responses after a vector bite.
Here, we will execute a paired study of exposed-unexposed skin to carefully examine the innate and adaptive immune responses in the skin and blood to exposure of the saliva of Aedes aegypti, the mosquito vector of dengue, Zika, and chikungunya viruses. We will enroll 42 participants to undergo vector feeding and give blood samples at baseline and 2 and 14 days later. Additionally, participants will give skin punch biopsy samples of bitten (exposed) and unbitten (unexposed) skin. For analysis, we will group 10-12 participants in each of 4 technical modality cohorts or groups : 1) immunohistochemistry, 2) RNA sequencing, 3) flow cytometry, and 4) T-cell receptor sequencing. With the current rise of vector-borne diseases in the United States and around the world, we hope the results of this study contribute to future vaccine design and clinical development strategies for vector#borne diseases.
Here, we will execute a paired study of exposed-unexposed skin to carefully examine the innate and adaptive immune responses in the skin and blood to exposure of the saliva of Aedes aegypti, the mosquito vector of dengue, Zika, and chikungunya viruses. We will enroll 42 participants to undergo vector feeding and give blood samples at baseline and 2 and 14 days later. Additionally, participants will give skin punch biopsy samples of bitten (exposed) and unbitten (unexposed) skin. For analysis, we will group 10-12 participants in each of 4 technical modality cohorts or groups : 1) immunohistochemistry, 2) RNA sequencing, 3) flow cytometry, and 4) T-cell receptor sequencing. With the current rise of vector-borne diseases in the United States and around the world, we hope the results of this study contribute to future vaccine design and clinical development strategies for vector#borne diseases.
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
False
Is a FDA Regulated Device?:
False
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
Secondary ID Infos
| Secondary ID | Type | Domain | Link | View |
|---|---|---|---|---|
| 20-I-N053 | None | None | View |