Flow Cytometric Immune Monitoring of B. Afzelii-Specific T Lymphocytes

N/ANot Yet RecruitingNCT07703787

University Hospital, Strasbourg, France20 enrolled

Overview

Lyme borreliosis diagnosis currently relies on clinical assessment and detection of Borrelia-specific antibodies. However, serology does not allow reliable assessment of active infection. Evaluation of the cellular immune response through Borrelia-specific T lymphocyte monitoring may provide complementary diagnostic and prognostic information. This study aims to assess Borrelia afzelii-specific T-cell responses using multiparameter flow cytometry after stimulation with standardized peptide pools. This approach enables the characterization of CD4+ and CD8+ T cells, including polyfunctional immune responses. The diagnostic and prognostic value of this immunomonitoring strategy will be evaluated in patients with acrodermatitis chronica atrophicans, a late manifestation of Lyme borreliosis associated with B. afzelii.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Lyme Borreliosis Lyme Disease

Eligibility

Sex: ALLMin age: 18 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Age ≥ 18 years * Subject informed of the results of the prior medical examination * Subject informed about the objectives, procedures, and potential risks of the study * Subject affiliated with a health insurance/social security scheme (beneficiary or dependent) * Subject having provided dated and signed informed consent * Lyme borreliosis/acrordermatitis chronica atrophicans (ACA) group: Subject presenting clinical and biological criteria or Borrelia identification confirming chronic atrophic acrodermatitis, with appropriate antibiotic treatment initiated less than 18 months ago or untreated • Control group: Healthy subject with no history of Lyme disease and negative Lyme serology Exclusion Criteria: * Body weight \< 50 kg * Pregnancy or breastfeeding * Diabetes mellitus * Immunodeficiency or ongoing immunosuppressive treatment (including oral corticosteroids) * Contraindication to local anesthesia with lidocaine, with or without adrenaline * Inability to provide informed consent (emergency situation, inability to understand study information, …) * Participation in another clinical trial * Legal protection measures (guardianship, curatorship, or legal safeguard)

Outcomes

Primary Outcomes

Characterization of Borrelia afzelii-specific T-cell immune responses by multiparameter flow cytometry

Descriptive analysis of antigen-specific T-cell responses after stimulation with Borrelia afzelii peptide pools using intracellular cytokine staining (ICS) and activation-induced marker (AIM) assays. Outcomes will include the polyfunctionality index of antigen-specific T cells, comparison of ICS and AIM responses, number of positive peptide pools, and magnitude of antigen-specific CD4+ and CD8+ T-cell responses.

Time frame: At study inclusion (baseline visit)