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Completed

NCT Number: NCT01379768

Study of the Cell Response in the Tear Film After Overnight Contact Lens Wear

The purpose of this study was to count and analyze the white blood cells in tear samples collected from study participants following sleep. The results from contact lens wearers were compared with the results from non-contact lens wearers.

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Key information

Conditions

White Blood Cells

Age range

17 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

University of Waterloo Centre for Contact Lens Research

Waterloo, Ontario, N2L 3G1, Canada

About this study

The objective of the study was to determine and compare the relative oxidative response of polymorphonuclear neutrophils (PMNs), the relative cell adhesion response of PMNs, and the leukocyte population in tear samples collected from contact lens wearers and non-contact lens wearers. Tear samples were collected via a binocular eye-wash. The samples were processed, and a cell count was performed using a hemacytometer. Flow cytometry was used to determine the expression of different PMN cell markers before and after stimulation with bacterial lipopolysaccharide (LPS).

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • 17 years of age or older.
  • Ocular examination in the last two years.
  • Has up-to-date spectacles.
  • Falls into one of the following three categories:
  • Adapted wearer of Lotrafilcon A contact lenses
  • Adapted wearer of Lotrafilcon B contact lenses
  • Does not wear contact lenses
  • Other protocol-defined inclusion criteria may apply.

Exclusion criteria

  • Ocular disease
  • Systemic or topical medications that may affect ocular health.
  • Known sensitivity to diagnostic pharmaceuticals used in study.
  • Uses artificial tears and/or rewetting drops.
  • Wears contact lenses on an overnight basis for more than one night per week.
  • Other protocol-defined exclusion criteria may apply.

Treatment and study plan

Lotrafilcon A contact lens

Device

Commercially marketed, silicone hydrogel, single-vision contact lens FDA-approved for daily and extended (overnight) wear for up to 30 nights.

Other names: AIR OPTIX NIGHT & DAY AQUA

Lotrafilcon B contact lens

Device

Commercially marketed, silicone hydrogel, single-vision contact lens FDA-approved for daily or extended (overnight) wear up to 6 nights.

Other names: NIGHT & DAY®

Clear Care Cleaning and Disinfection Solution

Device

Hydrogen peroxide-based contact lens care system for nightly cleaning and disinfection of study lenses

Other names: Clear Care®

Primary outcomes

  1. Leukocyte Population

    Time frame: Week 5

    A tear sample was collected after 8 hours of sleep using an ocular surface cell collection apparatus (OSCCA). Different types of white blood cells (leukocytes) were identified, which included neutrophils, monocytes, and lymphocytes. The total amount of leukocytes for contact lens wearers and non-lens wearers is presented. Potential differences in leukocyte count between lens wearers and non-lens wearers may indicate a different immune response.

  2. Relative Cell Adhesion Response of Polymorphonuclear Leukocytes (PMNs)

    Time frame: Week 5

    A tear sample was collected after 8 hours of sleep using an ocular surface cell collection apparatus (OSCCA) and analyzed on a flow cytometer. CD54 is a protein typically found in the cell membrane of leukocytes, which up-regulates during inflammation and promotes cell adhesion. Cell adhesion response is reported as a ratio of stimulated to non-stimulated samples.

  3. Relative Oxidative Response of Polymorphonuclear Leukocytes (PMNs)

    Time frame: Week 5

    A tear sample was collected after 8 hours of sleep using an ocular surface cell collection apparatus (OSCCA) and analyzed on a flow cytometer. Oxidative response is reported as a ratio of activated to non-activated samples. DCF (dichlorofluorescein diacetate) is a molecular probe that measures the oxidative burst. Upon stimulation, the PMNs synthesize reactive oxygen species, such as superoxide or hydrogen peroxide, which is detected by the probe. Differences in the oxidative response between contact lens wearers and non-lens wearers is indicated by a shift in the ratio (stimulated/unstimulated).

  4. Change From Week 1 in Leukocyte Population at Week 5

    Time frame: Week 1, Week 5

    A tear sample was collected after 8 hours of sleep using an ocular surface cell collection apparatus (OSCCA). Different types of white blood cells (leukocytes) were identified, which included neutrophils, monocytes, and lymphocytes. The difference between total leukocytes for contact lens wearers and non-lens wearers (Week 5 minus Week 1) is presented.

  5. Change From 1 Week in Relative Cell Adhesion Response of PMNs at Week 5

    Time frame: Week 1, Week 5

    A tear sample was collected after 8 hours of sleep using an ocular surface cell collection apparatus (OSCCA) and analyzed on a flow cytometer. Cell adhesion response is reported as a ratio of activated to non-activated samples. The difference between the ratio data for contact lens wearers and non-lens wearers (Week 5 minus Week 1) is presented.

  6. Change From Week 1 in Relative Oxidative Response of PMNs at Week 5

    Time frame: Week 1, Week 5

    A tear sample was collected after 8 hours of sleep using an ocular surface cell collection apparatus (OSCCA) and analyzed on a flow cytometer. Oxidative response is reported as a ratio of activated to non-activated samples. The difference between the ratio data for contact lens wearers and non-lens wearers (Week 5 minus Week 1) is presented.

Sponsors and collaborators

Lead sponsor

CIBA VISION

Industry

Collaborators

  • University of Waterloo

Registry information

Official study title

Polymorphonuclear Leukocyte Response During Overnight Lens Wear

Acronym: CORNWALL

Important dates

Study start
2011
Primary completion
2012
Study completion
2012
First posted
Jun 23, 2011
Registry last updated
Mar 8, 2013

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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