Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT02715323 |
| Other study ID # |
R1295/101/2015 (SERI-STIIC-3) |
| Secondary ID |
2016/2048 |
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
May 2016 |
| Est. completion date |
November 2019 |
Study information
| Verified date |
April 2024 |
| Source |
Singapore National Eye Centre |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
Ocular surface disease, especially dry eye and scleritis, commonly affects patients with
autoimmune diseases. Ocular surface immune cells are increased in autoimmune disease; however
the full subset of immune cells activated is unknown. Recent experimental studies show that
dendritic cells and T cells in the cornea are critically associated with corneal nerve
innervation. Corneal confocal microscopy (CCM) allows rapid non-invasive in vivo imaging of
dendritic cells and corneal nerves. The investigators propose to investigate how ocular
surface health, conjunctival immune cells and corneal nerve/dendritic cell morphology
interact in 3 rheumatological conditions: Sjogren's syndrome (SS), Rheumatoid arthritis (RA),
Systemic lupus erythematosus (SLE).
The preliminary flow cytometric studies show that various immune cells (eg: T cells, B cells,
and dendritic cells) can be quantified using minimally invasive impression membranes
(Eyeprim). Clinically, the research team is experienced in measuring features of ocular
surface inflammation (conjunctival redness, tear breakup times) with Oculus keratograph5M.
The investigators also aim to harvest conjunctival immune cells using impression cytology and
quantify specific cell types with flow cytometry. Corneal nerve morphology and dendritic cell
density and distribution will be assessed using CCM; in collaboration with the group who have
pioneered this technique.
The investigator anticipate that alterations in corneal nerve and dendritic cell parameters
will correlate with immune activation/inflammation, deterioration of tear function and
increased systemic severity of the rheumatological disease. In addition, the investigators
hypothesize that the lower the corneal nerve density, the higher the number of corneal
dendritic cells and conjunctival inflammatory cells. Studying these relationships may allow a
better mechanistic understanding of local corneal and systemic immune activation and the
development of a non-invasive ophthalmic surrogate marker of dendritic cell activation and
nerve fibre loss to aid earlier diagnosis, risk stratification and the development of new
therapies in autoimmune patients with severe dry eye.
Description:
1. BACKGROUND AND RATIONALE
1.1 General Introduction
Ocular surface disease, especially dry eye and scleritis, commonly affects patients with
autoimmune diseases. Ocular surface immune cells are increased in autoimmune disease;
however the full subset of immune cells activated is unknown. Recent experimental
studies show that dendritic cells and T cells in the cornea are critically associated
with corneal nerve innervation. Corneal confocal microscopy (CCM) allows rapid
non-invasive in vivo imaging of dendritic cells and corneal nerves. The investigators
propose to investigate how ocular surface health, conjunctival immune cells and corneal
nerve/dendritic cell morphology interact in 3 rheumatological conditions: Sjogren's
syndrome (SS), Rheumatoid arthritis (RA), Systemic lupus erythematosus (SLE).
The preliminary flow cytometric studies show that various immune cells (eg: T cells, B
cells, and dendritic cells) can be quantified using minimally invasive impression
membranes (Eyeprim). Clinically, the research team is experienced in measuring features
of ocular surface inflammation (conjunctival redness, tear breakup times) with Oculus
keratograph5M. The investigators also aim to harvest conjunctival immune cells using
impression cytology and quantify specific cell types with flow cytometry. Corneal nerve
morphology and dendritic cell density and distribution will be assessed using CCM; in
collaboration with the group who have pioneered this technique.
Investigators anticipate that alterations in corneal nerve and dendritic cell parameters
will correlate with immune activation/inflammation, deterioration of tear function and
increased systemic severity of the rheumatological disease. In addition, the
investigator hypothesize that the lower the corneal nerve density, the higher the number
of corneal dendritic cells and conjunctival inflammatory cells. Studying these
relationships may allow a better mechanistic understanding of local corneal and systemic
immune activation and the development of a non-invasive ophthalmic surrogate marker of
dendritic cell activation and nerve fibre loss to aid earlier diagnosis, risk
stratification and the development of new therapies in our autoimmune patients with
severe dry eye.
1.2 Rational for the Study Purpose
Dry eye, a type of chronic ocular surface inflammation, is highly prevalent and
contributes to corneal blindness and imposes a severe health burden. Scleritis is ocular
surface inflammatory disorder associated with mild to severe inflammation of the sclera
with or without intraocular inflammation. Severe dry eye or scleritis is associated with
autoimmune diseases like SS, RA, SLE, and other conditions. Current treatment of dry eye
is often not effective enough (eg., cyclosporine) or causes adverse effects (eg.,
corticosteroid-induced glaucoma). In autoimmune dry eye, there is immune-mediated damage
to the ocular surface and the lacrimal gland. In various models of dry eye disease, it
has been shown that components of the immune system such as T cells, macrophages and
cytokines such as interleukin (IL) 1β and tumor necrosis factor (TNF)-α are critical for
triggering and maintaining this disease. Likewise treatment of non-infective sclerits is
a very challenging situation to all uveitis specialists.
Ocular surface immune cells are increased when autoimmune disease is present, either the
proportion or number of a particular type of immune cell, eg. monocytes or CD4+ T cells
may be increased in the presence of more severe local inflammation and/or systemic
activity. A signature of immune cell infiltration may be present in a particular
rheumatological condition. If certain types of cells, (e.g., T cells or B cells) are
predominant in the systemic disease, it suggests that a T cell approach (e.g.,
tacrolimus) or B cell approach (e.g., rituxamab) may be used. Alternatively, if certain
cytokines play a major role in dry eye, an inhibitor of cytokine signalling such as a
JAK inhibitor may be used.
Recent studies have shown that dendritic cells and T cells in the cornea are critically
associated with corneal nerve innervation [1, 2]. This has been shown in both human and
animal studies [1-4]. At the same time, the technology for in vivo imaging of human
corneal nerves and dendritic cells and their quantification have greatly improved
recently. This has led to an explosion of interest in harnessing this technology as a
surrogate marker for peripheral neuropathies and to explore underlying mechanisms
[5-27]. The investigators have previously shown that first generation CCM can quantify
the presence and density of Langerhans cells (LCs) in Bowman's layer of the cornea in
patients with diabetes [28]. However the latest 3rd generation HRT III can be used to
classify and quantify Langerhans cells (LCs) into a mature phenotype (dendritic cell
bearing long processes) or an immature phenotype (non-dendritic cell lacking cell
dendrites) to provide insight into immune alterations in vivo [29]. A recent
experimental study in diabetic mice has used CCM to show that direct contact between DCs
and the corneal nerves may trigger nerve fiber damage [30].
Gap in scientific knowledge: Researchers have shown that proinflammatory cytokines are
elevated in tears of humans with dry eye; many of these may be secreted by immune cells.
They found in preliminary flow cytometric studies that CD4+ T cells, CD19+ B cells,
CD14+ monocytes, CD1c dendritic cells can be quantified using minimally invasive
impression membranes (Eyeprim)[31]. The full subset of immune cells activated in the
ocular surface in dry eye, and in various rheumatological conditions, is not known. The
proportions of these cells in different severity of dry eye and different systemic
activity of autoimmune disease have not been evaluated. Furthermore, it is uncertain
whether the integrity of cornea innervation is also a determinant of tear function in
patients with autoimmune systemic disease.
The research group has undertaken many clinical trials and imaging studies of the human
ocular surface. This includes measurements with Oculus (non-invasive tear breakup
times), staining, etc., and the measurement of cytokines using the multiplex bead based
sandwich immunofluorescence assay[32-38]
Preliminary Studies The research group has also optimized Eyeprim collection of
conjunctival immune cells and method of analysis using a panel of immune markers with
Amnis [31], a relatively new type of flow cytometry (Figure 1) coupled with microscopy
(Figure 2). The advantage of the Amnis technique is the direct visualization of analyzed
cells to permit co-localisation of signals. They have published on the validity of the
cell morphological parameter analysis using the Amnis software, compared to a human
grader [31]. In addition, they have also used conventional flow cytometry (BD FACS) to
quantify CD3, CD4, CD8, CCR7, CXCR3, CD109 and CD63 staining (data not shown).
In collaboration with the ENA team, their team has been trained in image acquisition
using CCM to enable quantification of corneal nerves and dendritic cells [1, 2, 4, 9,
10, 13, 14, 16, 21, 27](Figure 3). Sub-basal corneal nerve fibre density, corneal nerve
branch density, corneal nerve fibre length and tortuosity (Figure 3, 4) will be
quantified using both manual (CCMetrics) and automated (ACCMetrics) image analysis
software, developed by the ENA team. Sub-basal mature and immature dendritic cell
density and distribution in relation to corneal nerves will be quantified.
The collaborators, Prof Malik and Dr. Petropoulos are leading the Early neuropathy
assessment (ENA team-http://qatar-weill.cornell.edu/research/faculty/eng/index.html) and
have pioneered the use of in vivo CCM as a rapid, non-invasive ophthalmic instrument to
monitor diabetic and other peripheral neuropathies. They will actively engage in
training and overseeing optimal image capture and will provide the necessary software
and licensing privileges to enable detailed quantification and interpretation [9, 10,
12-14, 16, 17, 20, 21, 23-27].
2. HYPOTHESIS AND OBJECTIVES Overall long term objective: Discover safe and effective
treatment for ocular surface inflammation and define the ocular surface indications for
clinical usage of medications targeting the immune system in rheumatological disease.
Clinical / Healthcare implications: There are many benefits in using CCM in autoimmune
disease. CCM allows rapid, non-invasive imaging of the corneal nerves and dendritic
cells to determine the level of inflammation and its consequence in autoimmune diseases.
This will allow earlier diagnosis, risk stratification and more timely intervention at
the rheumatology clinics, enhancing multidisciplinary care of autoimmune patients. The
investigator will build a normative database (either ethnic or local age specific data
from a reading centre) by using this study as a platform to recruit more patients.
Basic science implications: Advance understanding of relationship between corneal nerves
and tear function/immunology.
Short term objectives: researchers propose a nationwide study in collaboration with Tan
Tock Seng Hospital to study clinical features and conjunctival immune cells in patients
with ocular surface inflammatory disease with or without associated systemic autoimmune
or collagen vascular disease.
Academic objectives: Aim to:
- Enhance multidisciplinary collaborations, between SERI and S Albani from STIIC
(cell analysis)
- Build new collaborations (TTSH ophthalmologist Dr R Agrawal)
- Increase value/synergy from currently approved funding: SERI pilot grant
(recruitment of pilot participants and optimization of tools),
- Compete for future funding, NMRC STAR award, CS or CBIRG.
Expected findings:
- Different systemic severities of the rheumatological diseases, symptoms of dry eye,
tear function, NIKBUT and corneal staining may correlate with corneal nerve and
dendritic/non-dendritic cell defects.
- Tear cytokines may correlate with corneal nerve and dendritic/non-dendritic cell
defects.
- Change in the density and subtypes of T cells or other cells such as dendritic in
the conjunctiva (impression cytology) may correlate with corneal nerve and
dendritic/non-dendritic cell defects.
2.3 Potential Risks and Benefits: 2.3.1 Potential Risks
- It is possible that there may be some slight discomfort during the sampling of
conjunctival cells using the impression membrane
- Some slight discomfort or redness from tear fluid collection (Schirmer test)
- Rarely a corneal epithelial defect may occur from in vivo confocal microscopy, but
this generally heals in 1-2 days. Corneal epithelial defect means that a layer of
the cornea is broken, liken to what happened during an abrasion.
- Stinging sensation as a result of local anaesthetic (Alcaine)
2.3.2 Potential Benefits With greater understanding of the presence of various
inflammatory mediators, the investigators can gain further insight into the complex
process taking place in autoimmune diseases patients.
3. STUDY POPULATION 3.1 List The Number and Nature of Subjects to be Enrolled. The
investigators will recruit patients with 3 specific rheumatological diagnoses and
controls
- SS (n=40), RA (n=40), SLE (n=40)
- Healthy age/ethnicity/sex matched control subjects (n=40)
Total sample size: 160
4. STUDY DESIGN This is a cross-sectional study involving 160 participants. Study duration:
One visit, recruitment duration: 1 Year
4.1.1 Screening Visit and Procedures Screening visit and procedures will be done on a
separate day. Participants referred from TTSH will be allocated a time slot to come to SERI
for the ocular examinations. On the day of procedure, SERI coordinator will screen for
eligible subjects by asking them some questions base on the inclusion and exclusion
checklist. If found to be eligible and participants are interested, consent will be taken at
SERI and SERI optometrist will proceed with the ocular assessments.
4.1.2 Study Procedures
The examinations will be done by SERI study team members. The list of required examinations
is shown:
1. Dry Eye Symptoms (SPEED Questionnaire)
2. Non-invasive Tear Break-up Time (NIKBUT)- Oculus K5M
3. Conjunctival Redness- Oculus K5M
4. Tear collection from Schirmers strip
5. Impression Cytology- using EyePrim conjunctival membranes
6. Corneal Fluorescein Staining- Oculus K5M
7. In vivo corneal confocal microscopy (CCM)
8. Retrieval of clinical information from participants
