A Pilot Study to Finetune Skin Processing Procedures in Recent Vaccinees, Prior to GeKoSkimm Study Initiation (GeKoSkimm-pilot)

Not Applicable

Completed

• Conditions: Yellow Fever
• Interventions: Other: Skin biopsy

• Registration Number: NCT06539351
• Lead Sponsor: Institute of Tropical Medicine, Belgium

Brief Summary

This pilot study aims to optimize the sample processing techniques for collecting and analyzing skin biopsies obtained from individuals routinely vaccinated against yellow fever. By addressing logistical challenges early, risks will be mitigated and the main study's efficiency will be enhanced.

In order to do so, 15 participants will be identified at the ITM polyclinic after receiving a yellow fever vaccination. Participants will be invited to one study visit at the ITM Clinical Trial Site (CTS) 28 days after vaccination to collect blood samples, skin punch biopsies and a minimally-invasive microbiopsy at the site of vaccination. To investigate the ideal location for the skin punch biopsies, participants will be divided in 3 groups; in the first 5 participants the biopsies will be taken directly on the vaccination site, for the next 5 participants, the biopsies will be taken at +/- 3 cm distance from the vaccination site, and for the last five participants, the biopsies will be taken at +/- 10 cm distance from the vaccination site.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2024-07-29
• Study First Submitted QC: 2024-08-01
• Study First Posted: 2024-08-06
• Study Start: 2024-09-09
• Primary Completion: 2024-11-25
• Study Completion: 2024-11-25
• Status Verified: 2025-05
• Last Update Submitted: 2025-05-08
• Last Update Posted: 2025-05-09

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 15

Inclusion Criteria

• BMI lower than 30kg/m²
• Able and willing to provide written informed consent
• Having received a yellow fever vaccination 28 days (+2 or -2 days) ago

Exclusion Criteria

• Any confirmed or suspected immunosuppressive or immunodeficient state (incl. cancer); asplenia; recurrent severe infections and use of immunosuppressant medication within the last 6 months prior to recruitment, except topical or short-term oral steroids
• History of bleeding disorder (e.g., factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following venipuncture
• Any other significant disease, disorder, planned surgery, or finding which may significantly affect the ability of the volunteer to participate in the study
• Tendency to keloid (scar) formation in response to skin damage

Skin diseases at the biopsy or vaccination site

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
All participants	Skin biopsy	-

Primary Outcome Measures

Name	Time	Method
Optimize sample processing for optimal cell yield	1 day	To test the sample processing flow. This involves evaluating the efficiency and practicality of sample collection, preservation, and analysis protocols to ensure optimal cell yield.

Secondary Outcome Measures

Name	Time	Method
Absolute number of YFC-specific TRM cells per skin biopsy	1 day	Using different skin dissociation protocols, the absolute number of YFV-specific TRM cells that can be isolated out of 4mm punch biopsy skin samples, as determined by flow cytometry.
percentage of YFC-specific TRM cells per skin biopsy	1day	Using different skin dissociation protocols, the percentage of YFV-specific TRM cells that can be isolated out of 4mm punch biopsy skin samples, as determined by flow cytometry.

Trial Locations

Locations (1)

Clinical Trial Site ITM; 🇧🇪 Antwerp, Belgium