Human Subcutaneous Inflammatory Response to Glucose Sensors (TISSUESENSOR)

Human Subcutaneous infLammatory Response to Glucose Sensors: Impact on the Quality of the Measure

The aim of the study is to describe the inflammatory response to enzimatic glucose sensors after 10 days of use and to evaluate the relationship between the magnitude of the FBR (foreign body response) with the accuracy of the sensor (MARD)

Study Overview

• Status: Completed
• Conditions: Inflammatory Response to Glucose Sensors
• Intervention / Treatment: Device: glucose sensor

Detailed Description

Eighteen Type 1 DM patients are going to be included. Primary Objectives

1. To define the intra-individual and inter-individual variability of the macrophage count around the sensor
2. To assess whether there is a relationship between the number of macrophages, fibrosis and MARD of the MCG registry.

Secondary Objectives

To describe the histology of tissue response. This description will include:

1. HE stain: cell types, arrangement, vascular structures, signs of hemorrhage-clot. Giemsa stain: mast cells. Masson's trichrome stain: str. vascular.
2. Immunohistochemistry: Vascular assessment, characterization of macrophages

Each patient will have 1 glucose sensor inserted in the non-dominant arm. During the useful life of the sensor (10), a minimum of 4 capillary blood glucose determinations/day will be performed The sensor has a length of 8 mm and a diameter of 0.4 mm. All the necessary material will be provided, including a control diary to help the patient remember to carry out the self-control and set its time distribution.

On the last day of sensor use, it will be removed and a 4-mm punch skin biopsy will be performed 5 minutes later.

Tissue samples will be fixed in 4% formaldehyde solution, paraffin blocks made and sectioned. The resulting samples will be stained Semiquantitative determination of lymphocytes, neutrophils, mast cells, macrophages will be performed; fibrin, fibrosis, vascular proliferation and karyorrhexis

In all cases, a quantitative immunohistochemical study will be performed with x40 field counting with photographs and grid (Dako omnis with envision system) for:

Macrophages

The monitor-glucometer will be recovered for download and study of the record. The interstitial glucose - blood pairs will be made with those recorded but not used for callibration.

Glucose sensor values and insulin doses will be recover from tha medical application

• Study Type: Observational
• Enrollment (Actual): 24

Contacts and Locations

Study Locations

• Spain
  • Barcelona
    • Sabadell, Barcelona, Spain, 08208
      • Hospital Parc Tauli

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Eighteen people diagnosed with type 1 diabetes and treated with closed-loop systems

Description

Inclusion Criteria:

• 1. Type 1 diabetes of more than 6 months duration, confirmed by positivity for Ab antiGAD 65 2. Be a regular user of a continuous glucose monitoring system 2. To Understand the proposed protocol and acceptance of participation.

Exclusion Criteria:

• Treatment with drugs that could potentially modify the inflammatory response during the 10 days prior to surgery (non-steroidal anti-inflammatory drugs or corticosteroids, antioxidants or platelet antiaggregants).

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Biopsy performed; after 10 days of use, the sensor is removed and the biopsy performed	Device: glucose sensor; skin biopsy (punch)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Macrophages sourronding the sensor		10 days
MARD (CGM record for 10 days)	median absolute relative difference (BG- Sensor glucose)	10 days

Collaborators and Investigators

• Sponsor: Corporacion Parc Tauli

Publications and helpful links

General Publications

• Rigla M, Pons B, Rebasa P, Luna A, Pozo FJ, Caixas A, Villaplana M, Subias D, Bella MR, Combalia N. Human Subcutaneous Tissue Response to Glucose Sensors: Macrophages Accumulation Impact on Sensor Accuracy. Diabetes Technol Ther. 2018 Apr;20(4):296-302. doi: 10.1089/dia.2017.0321. Epub 2018 Feb 22.

Study record dates

Study Major Dates

• Study Start (Actual): June 21, 2022
• Primary Completion (Actual): July 12, 2023
• Study Completion (Actual): September 20, 2023

Study Registration Dates

• First Submitted: February 23, 2023
• First Submitted That Met QC Criteria: February 23, 2023
• First Posted (Actual): March 6, 2023

Study Record Updates

• Last Update Posted (Actual): September 28, 2023
• Last Update Submitted That Met QC Criteria: September 27, 2023
• Last Verified: September 1, 2023

More Information

Terms related to this study

• Keywords: Enzymatic glucose sensors, foreign body response
• Other Study ID Numbers: PI18/01118

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes