Treg Effector Function and Th2/Treg Ratio in Allergic Conjunctivitis: Effect of Desensitization Therapy

NCT07171307 | Not Yet Recruiting

• 3 other identifiers: CEI-2024/06/16CI-032-2024CB-031-2024
• Study Type: observational
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to evaluate the effector function and expression of TIGIT and PD-1 on Tregs, as well as the Th2/Treg ratio, in patients with allergic conjunctivitis with and without desensitization therapy, compared to healthy controls. Peripheral blood and tear samples will be collected once at enrollment. Treg and Th2 populations will be immunophenotyped, TIGIT and PD-1 expression assessed, and functional assays performed. Cytokine and antibody (IgE, IgG4) concentrations will be measured in serum and tears. Results will be analyzed using descriptive statistics, Shapiro-Wilk test for distribution, t-tests or ANOVA for group comparisons, and correlation analyses for associations, with p\<0.05 considered significant. This study seeks to identify immunological markers associated with disease severity and treatment response, potentially informing future therapeutic strategies.

Conditions

Conjunctivitis, Allergic

Keywords

conjunctivitis allergic; TIGIT; Tregs; PDL-1

Outcome Measures

Primary Outcomes (4)

• To evaluate the effector function and the expression of TIGIT and PD-1 molecules on regulatory T cells, as well as the Th2/Treg, in patients with allergic conjunctivitis with and without allergen-specific immunotherapy, and in healthy control subjects.

  Patients with allergic conjunctivitis, both with and without desensitization treatment, as well as healthy subjects as a control group, will be included in the study. Peripheral blood and tear samples will be collected from all participants. Peripheral blood samples will be used for immunophenotyping of Treg and Th2 lymphocytes and for assessing the expression levels of the effector molecules TIGIT and PD-1.

  At baseline (single assessment at enrollment in all study and control groups)

• Proportion of Treg and Th2 lymphocytes and Th2/Treg ratio in peripheral blood

  Peripheral blood mononuclear cells will be immunophenotyped to quantify Treg and Th2 populations and calculate the Th2/Treg ratio.

  At baseline (single assessment at enrollment in all study and control groups)

• Cytokine profile associated with Treg and Th2 lymphocytes in serum and tears

  Concentrations of cytokines related to Treg (e.g., IL-10) and Th2 (e.g., IL-4, IL-5, IL-13) will be measured in serum and tear samples.

  At baseline (single assessment at enrollment in all study and control groups)

• Effector function of Treg lymphocytes assessed by TIGIT and PD-1 expression and functional assays.

  Treg cells will be analyzed for expression of effector molecules TIGIT and PD-1, and functional assays will be performed to assess suppressive capacity.

  At baseline (single assessment at enrollment in all study and control groups)

Secondary Outcomes (2)

• Concentration of IgE and IgG4 antibodies in serum and tears

  At baseline (single assessment at enrollment in all study and control groups)

• Correlation of immunological parameters with ocular symptom severity and treatment response

  At enrollment (clinical evaluation performed once in all study and control groups)

Study Arms (3)

Conjunctivitis Allergic with allergen-specific immunotherapy (AIT)

The study subjects will be patients with a confirmed diagnosis of allergic conjunctivitis, active symptoms, and positive skin tests, who do not present any other type of systemic or local disease or inflammatory process and who are receiving allergen-specific immunotherapy (AIT).

Conjunctivitis Allergic without allergen-specific immunotherapy (AIT)

The study subjects will be patients with a confirmed diagnosis of allergic conjunctivitis, active symptoms, and positive skin tests, who do not present any other type of systemic or local disease or inflammatory process, and who are not receiving immunotherapy treatment.

Control group

The control subjects will be clinically healthy individuals, with a normal ocular surface and no evidence of active ocular disease or local or systemic inflammatory or infectious processes.

Eligibility Criteria

• Age: 5 Years - 30 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The study subjects are patients recruited from the outpatient clinic of "Clinical Immunology" at Instituto de Oftalmologia Conde de Valenciana. All patients are evaluated by specialists in ophthalmology and allergy.

You may qualify if:

• Subjects aged between 5 and 30 years, of either sex.
• Subjects with a confirmed diagnosis of allergic conjunctivitis.
• Presence of active symptoms.
• Positive skin tests.
• Willingness to participate in the protocol by signing informed consent.

You may not qualify if:

• Subjects who have had an infection within the two months prior to sample collection.
• Patients with other active systemic allergic diseases (such as bronchial asthma, dermatitis, among others).
• Subjects with chronic-degenerative or autoimmune diseases.
• Subjects who have received topical immunosuppressive treatment in the last two months.
• Subjects receiving systemic immunosuppressive therapy.

Sponsors & Collaborators

• Instituto de Oftalmología Fundación Conde de Valenciana: lead

Study Sites (1)

Instituto de Oftalmología FAP Conde de Valenciana, IAP Sede Centro

Mexico City, Mexico City, 06800, Mexico

Location

Related Publications (2)

• Kucuksezer UC, Ozdemir C, Cevhertas L, Ogulur I, Akdis M, Akdis CA. Mechanisms of allergen-specific immunotherapy and allergen tolerance. Allergol Int. 2020 Oct;69(4):549-560. doi: 10.1016/j.alit.2020.08.002. Epub 2020 Sep 6.

  PMID: 32900655 BACKGROUND

• Calzada D, Baos S, Cremades-Jimeno L, Cardaba B. Immunological Mechanisms in Allergic Diseases and Allergen Tolerance: The Role of Treg Cells. J Immunol Res. 2018 Jun 14;2018:6012053. doi: 10.1155/2018/6012053. eCollection 2018.

  PMID: 30013991 BACKGROUND

Biospecimen

Retention: SAMPLES WITH DNA

Blood and tear samples will be collected from patients with and without desensitization therapy, as well as from healthy control subjects. Blood samples will be collected via venipuncture into EDTA tubes for whole blood and into serum separator tubes for serum isolation. Tear samples will be collected by capillarity using sterile borosilicate tubes and physiological saline solution. Whole blood samples will be used immediately for immunophenotyping of Th2 and Treg lymphocytes, as well as for the isolation of mononuclear cells (MNCs). Serum and tear samples will be stored at -80°C until analysis of cytokines, IgE, and IgG4.

MeSH Terms

Conditions

Conjunctivitis, Allergic

Condition Hierarchy (Ancestors)

Conjunctivitis; Conjunctival Diseases; Eye Diseases; Hypersensitivity, Immediate; Hypersensitivity; Immune System Diseases

Central Study Contacts

María del Carmén Jiménez Martínez

CONTACT

5554421700; mcjimenezm@institutodeoftalmologia.org

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Target Duration: 1 Day
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Head of the Immunology Department, Research Unit

Study Record Dates

• First Submitted: September 1, 2025
• First Posted: September 12, 2025
• Study Start: January 1, 2026
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): September 1, 2026
• Last Updated: September 17, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will not share

Locations

ME (1)