Examining immune responses to pneumococcal vaccination using lymph node aspiration

Optimisation of Lymph Node Fine Needle Aspiration to Study Pneumococcal Vaccine-induced Immunity

Not applicable Interventional Leiden University Medical Center · NCT06202703

This study is testing how well pneumococcal vaccines work by looking at immune responses in healthy adults aged 20 to 40 to help improve future vaccines.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment5 (estimated)
Ages20 Years to 40 Years
SexAll
SponsorLeiden University Medical Center Academic / other
Locations1 site (Leiden)
Trial IDNCT06202703 on ClinicalTrials.gov

What this trial studies

This study investigates the immune response generated by pneumococcal vaccines by analyzing germinal center B cell frequency through fine needle aspiration of lymph nodes. The research aims to determine the timing of peak immune responses following vaccination, which could provide insights into the mechanisms of vaccine-induced immunity. By understanding these immune responses, the study seeks to inform future vaccine design and optimize dosing intervals. Participants will be healthy adults aged 20 to 40 who meet specific health criteria.

Who should consider this trial

Good fit: Ideal candidates for this study are healthy adults aged 20 to 40 without significant co-morbidities.

Not a fit: Patients with a BMI over 30, those who are pregnant or breastfeeding, or individuals with documented pneumococcal vaccination or infection will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved vaccine designs that enhance immunity against pneumococcal diseases.

How similar studies have performed: While this approach is relatively novel, similar studies have shown promise in understanding immune responses to vaccines.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Participants between the ages of 20 and 40 years old
* Participants should be generally healthy and without substantial co-morbidities, including all auto-immune diseases that are being actively treated with immunosuppressive therapy. Patients with chronic diseases that do not require immunosuppressive therapy and are stable, defined as not requiring change of therapy or hospitalization in the six weeks preceding study enrollment, might be eligible for this study.

Exclusion Criteria:

* BMI \> 30 kg/m2
* Pregnancy at time of inclusion
* Breastfeeding during the course of the study
* Documented pneumococcal vaccination and/or infection
* Pneumococcal infection is defined as any infection that is microbiologically confirmed to be caused by S. pneumoniae (e.g. positive blood or sputum cultures for S. pneumoniae, positive urine S. pneumoniae antigen test)
* Documented HIV infection
* Documented primary immune disorder or primary coagulopathy
* Use of immunosuppressive medication or anticoagulants
* Known hypersensitivity to any of the vaccine components
* Recent (i.e. \<4 weeks before inclusion) surgery in axillar area or major surgery elsewhere
* Vaccination with any vaccine \< 1 month before inclusion
* Subjects vaccinated 1 - 6 months before enrolment can be included into the study. Study vaccine will be injected in the contralateral arm.
* Fever at time of inclusion

Where this trial is running

Leiden

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Vaccine-Preventable Diseases
Last reviewed 2026-06-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.