NCT06039527

Brief Summary

Rationale: Individuals with advanced age are at a progressively increasing risk of acquiring lower respiratory tract infections. Besides calendar age, the degree of frailty also associates with increased susceptibility to pneumonia requiring hospitalization. How alterations in the mucosal immune system with advanced age predispose to infections remains unclear as access to relevant tissue samples is limited. With minimally-invasive nasal sampling methods, it was recently observed that in vital older adults, both CD4+ T cells and CD8+ T cells are selectively lost from the nasal mucosa. However, the exact phenotype, underlying mechanisms, key molecules and consequences of this have not yet been investigated. Objective: Elucidate the mechanisms underlying the loss of nasal T cells and characterize in depth the differences of T cells in young and older adults and associate this loss with susceptibility to infections. Study design: Prospective cohort study Study population: Participants will be recruited from 3 groups:

  • healthy young adults (18-30 years, n=50)
  • vital older adults (\>65 years, n=60)
  • frail elderly (\>65 years, n=60). This group includes individuals without a history of recurrent respiratory infections or with \>2 self-reported episodes of respiratory infection in the past year. Main study parameters/endpoints: Frequency of nasal CD8+ T cells in young adults and frail older adults. Secondary study parameters/endpoints:
  • Phenotype (subsets, activation status), functionality, transcriptomic state, clonality and frequency of nasal and blood T cell populations
  • Stability of T cells and other immune parameters, as described for main study parameter, during a second sample after 3 months.
  • Analysis of other immune populations as for main study parameter
  • Concentration of nasal and systemic factors (e.g. cytokines and metabolites) and their association with T cells and other immune populations
  • Respiratory tract microbiota profiles and presence of asymptomatic viral infections and their association with T cells and other immune parameters
  • Chronological and biological age, sex, and other immunologically relevant parameters with T cell populations and other immune parameters
  • Alteration of T cell phenotype, during and following respiratory tract infections. Levels of antigen-specific T cells and other immune parameters in nose and blood post infection.

Trial Health

57
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
170

participants targeted

Target at P50-P75 for all trials

Timeline
Completed

Started Jan 2021

Longer than P75 for all trials

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

January 24, 2021

Completed
2.6 years until next milestone

First Submitted

Initial submission to the registry

September 1, 2023

Completed
14 days until next milestone

First Posted

Study publicly available on registry

September 15, 2023

Completed
2.6 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 1, 2026

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

May 1, 2026

Completed
Last Updated

September 9, 2025

Status Verified

September 1, 2025

Enrollment Period

5.3 years

First QC Date

September 1, 2023

Last Update Submit

September 2, 2025

Conditions

Outcome Measures

Primary Outcomes (1)

  • Frequency of nasal CD8+ T cells in young adults and frail older adults.

    CD8 T cells relative to nasal epithelial cells (ratio)

    baseline sample or month 3 sample

Secondary Outcomes (16)

  • Phenotype of nasal and blood T cell populations in young adults, healthy older adults and frail older adults that suffer from recurrent respiratory tract infections or not.

    baseline sample or month 3 sample

  • Functionality of nasal and blood T cell populations in young adults, healthy older adults and frail older adults that suffer from recurrent respiratory tract infections or not.

    baseline sample or month 3 sample

  • Transcriptomic cluster composition of nasal and blood T cell populations in young adults, healthy older adults and frail older adults that suffer from recurrent respiratory tract infections or not, as frequency of T cell subsets.

    baseline sample or month 3 sample

  • Clonality of nasal and blood T cell populations in young adults, healthy older adults and frail older adults that suffer from recurrent respiratory tract infections or not.

    baseline sample or month 3 sample

  • Stability of nasal T cells, as described for main study parameter, during a second sample after 3 months.

    baseline sample versus month 3 sample

  • +11 more secondary outcomes

Study Arms (3)

Young adults

N=50 of this group No intervention. Sampling at timepoint 0 and for 50% of the group another sample at 3 months If respiratory symptoms develop in the 3 months after timepoint 0, participants are invited to provide a NPS/OPS to identify causative agent, and if one is established, individuals are sampled 3 more times at months 1, 3 and 5 post symptom onset

Vital elderly

N=60 of this group No intervention. Sampling at timepoint 0 and for 50% of the group another sample at 3 months If respiratory symptoms develop in the 3 months after timepoint 0, participants are invited to provide a NPS/OPS to identify causative agent, and if one is established, individuals are sampled 3 more times at months 1, 3 and 5 post symptom onset

Frail elderly

N=60 of this group. Half with recurring respiratory infections, and half without No intervention. Sampling at timepoint 0 and for 50% of the group another sample at 3 months If respiratory symptoms develop in the 3 months after timepoint 0, participants are invited to provide a NPS/OPS to identify causative agent, and if one is established, individuals are sampled 3 more times at months 1, 3 and 5 post symptom onset

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

Study population: Investigators will recruit participants from 3 groups: * healthy young adults (18-30 years, n=50) * vital older adults (\>65 years, n=60) * frail elderly (\>65 years, n=60). These will be consist of individuals without a history of recurrent respiratory infections or with \>2 self-reported episodes of respiratory infection in the past year. Frailty will be determined by a clinical frailty score. The Clinical Frailty Scale (CFS) is a scale that caretakers can use to identify level of frailty in older patients from 1 (very fit) through 9 (terminally ill). For the present study, "vital older patients" are defined as those with a CFS of 1-3 and "older patients living with frailty with a CFS of 4 or higher".

You may qualify if:

  • Adults able and willing to provide informed consent.
  • Young adults aged 18-30 years old
  • Healthy elderly aged \>65 years old
  • Frail elderly \>65 years old
  • Clinical Frailty score healthy elderly 1-3
  • Clinical Frailty score frail elderly \>3
  • Self-reported respiratory tract infection in previous year healthy elderly 0-1
  • Self-reported respiratory tract infection in previous year frail elderly 0-1 or \>1

You may not qualify if:

  • Incompetence to provide informed consent prior or during study
  • Current smoker or \>40 pack year history
  • History of severe nose bleedings
  • Diagnosed with asthma, COPD or chronic rhinosinusitis
  • Use of inhalation corticosteroids or antibiotics in the past 6 weeks
  • Current use of anti-coagulants (to prevent nosebleeds). Platelet inhibitors like acetylsalicylzuur (Ascal) are allowed.
  • Respiratory tract infection or common cold in the past 2 weeks
  • Immunocompromised individuals (with primary immune deficiency or secondary immune deficiency)
  • Life expectancy \<28 days in the opinion of study physician
  • Vaccination in the 2 months prior to study start. A potential subject that is only excluded from participation based on a recent vaccination will be asked to re-participate 2 months post vaccination.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Leiden University Medical Center

Leiden, South Holland, 2333ZA, Netherlands

RECRUITING

Biospecimen

Retention: SAMPLES WITH DNA

Investigators will collect the following samples: * peripheral blood * nasopharyngeal swab * oropharyngeal swab * nasal curettes * nasosorption

MeSH Terms

Conditions

Respiratory Tract Infections

Condition Hierarchy (Ancestors)

InfectionsRespiratory Tract Diseases

Study Officials

  • Simon P Jochems, PhD

    LUMC

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Simon P Jochems, PhD

CONTACT

Study Design

Study Type
observational
Observational Model
COHORT
Time Perspective
PROSPECTIVE
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Assistant professor

Study Record Dates

First Submitted

September 1, 2023

First Posted

September 15, 2023

Study Start

January 24, 2021

Primary Completion

May 1, 2026

Study Completion

May 1, 2026

Last Updated

September 9, 2025

Record last verified: 2025-09

Data Sharing

IPD Sharing
Will not share

As even pseudonymized data is considered personal data as these can sometimes be traced back to an individual, data can be requested from the PI. If requests fall within the scope of the informed consent and study protocol, an MTA/DTA can be shared. Data will be posted on repositories with restricted access.

Locations