Over the past 8 years, Drs. Ackerman, Furuta and their colleagues have completed a number of studies that have been presented at national meetings and in a peer-reviewed publication, demonstrating the ability of the Esophageal String Test™ (EST) to capture luminal inflammatory mediators. These studies have consisted of:

  1. in vitro assays, showing that eosinophil products adhere to the string in a time and concentration-dependent fashion.

  2. in vivo clinical studies, revealing the EST can capture luminal eosinophil granule proteins from subjects with EoE following an overnight incubation. 

  3. more in vivo clinical studies, determining that the analytes in the EST sample provide a highly significant correlation with levels found in the mucosal tissue biopsy—the gold standard test.

  4. additional clinical studies determining that the EST is safe and well-tolerated.

In Vitro Assays and In Vivo Clinical Studies

The Oesophageal String Test: A Novel, Minimally Invasive Method Measures Mucosal Inflammation in Eosinophilic Oesophagitis — These results show the EnteroTracker®’s ability to capture and quantitate esophageal biomarkers in a minimally invasive fashion that reflects disease status based on biopsies (gold standard).

Furuta GT, et al. The Oesophageal String Test: A Novel, Minimally Invasive Method Measures Mucosal Inflammation in Eosinophilic Oesophagitis. Gut 2013; 62:1395-1405.

Additional Clinical Evidence:

Similarly, the EST has undergone a further study that has verified the same findings in testing done in a one-hour time frame. These studies have been presented in oral and poster presentations at national (Digestive Disease Week, Orlando, FL USA) and international meetings (International Eosinophil Society-IES, Oxford UK). These studies have consisted of clinical studies determining that:

  • the EnteroTracker® can capture luminal eosinophil granule proteins from EoE subjects after 1 hour.
  • the analytes in the EST sample provide a highly significant correlation with levels found in the mucosal tissue, the gold standard test.
  • additional mediators, including EoE-relevant cytokines, can be sampled with the EST device.
  • head-to-head comparison of the EST device to endoscopy revealed that the EnteroTracker was almost universally preferred by parents and patients over endoscopy.
  • the EnteroTracker® is safe and well-tolerated.

Data obtained in the above studies were procured from adults and children, male and female subjects at different study sites in Denver and Chicago.

Published Papers using the Esophageal String Test™:

One-Hour Esophageal String Test: A Nonendoscopic Minimally Invasive Test That Accurately Detects Disease Activity in Eosinophilic Esophagitis
Ackerman SJ, et al. (2019). The American Journal of Gastroenterology, 1. doi: 10.14309/ajg.0000000000000371

Esophageal Microbiome in Eosinophilic Esophagitis
Harris JK, et al. (2015). PLoS ONE, 10(5). doi: 10.1371/journal.pone.0128346

The Esophageal String Test (EST): A Novel Minimally Invasive Method for Measuring Esophageal Inflammation in Eosinophilic Esophagitis (EoE)
Furuta GT, et al. (2013). Gut, 62(10):1395-405. PMID: 22895393

Novel Device to Sample the Esophageal Microbiome - The Esophageal String Test
Fillon SA, et al. (2012). PLoS ONE, 7(9). doi:10.1371/journal.pone.0042938

Abstracts on the Esophageal String Test™:

The 1-Hour Esophageal String Test: A Non-Endoscopic Minimally Invasive Test to Accurately Detect Disease Activity in Eosinophilic Esophagitis
Ackerman SJ, et al.  J. Allergy and Clin Immunol 2019; 143(2): Ab309-Ab309.

The Minimally Invasive Esophageal String Test Measures Changes in Mucosal Inflammation in Pediatric Eosinophilic Esophagitis During Treatment: A Longitudinal Study
Amsden K, et al. Poster Presentation at the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN). J. Ped. Gastroenterol. Nutr. (JPGN) October, 2013.

A Novel Minimally Invasive Esophageal String Test Measures Changes in Mucosal Inflammation in Pediatric Eosinophilic Esophagitis During Treatment
Amsden K, et al. Poster Presentation at the International Falk Workshop, September 5, 2013. Graz, Austria on GERD: Gastroesophageal Reflux Disease.

Determination of the Molecular Phenotype of Esophageal Mucosal Inflammation in Children with Eosinophilic Esophagitis Using a 1-hour Esophageal String Test (EST)
Ackerman SJ, et al. Oral Presentation at the 8th International Symposium of the International Eosinophil Society, Keeble College, Oxford University, UK. July 13-17, 2013.

The Esophageal String Test (EST) Quantifies Luminal Eosinophil and Chemokine Biomarkers Reflective of Esophageal Inflammation in Adults with Eosinophilic Esophagitis (EoE)
Ackerman SJ, et al. Poster Presentation at the 8th International Symposium of the International Eosinophil Society, Keeble College, Oxford University, UK. July 13-17, 2013.

The Esophageal String Test (EST) Quantifies Luminal Eosinophil and Chemokine Biomarkers Reflective of Esophageal Inflammation in Adults with Eosinophilic Esophagitis (EoE)
Ackerman SJ, et al. Submitted to Digestive Disease Week (DDW) 2013. Programmed as Oral Talk, May 21, 2013, Orlando, Florida.

Determination of the Molecular Phenotype of Esophageal Mucosal Inflammation in Children with Eosinophilic Esophagitis Using a 1-hour Esophageal String Test (EST)
Ackerman SJ, et al. Digestive Disease Week (DDW) 2013. Programmed as Poster Presentation, May 19, 2013, Orlando, Florida.

Novel Proteomic Analysis of Esophageal Inflammation
Jonscher K, et al. J Biomol Tech. 2011; October; 22 (Supplement):S66. PMCID: PMC3186572

The Esophageal String Test (EST) Captures Charcot-Leyden Crystal Protein/Galectin-10 (CLC/Gal-10) as a Disease-Specific Biomarker of Active Eosinophilic Esophagitis (EoE)
Ackerman SJ, et al. North American Society for Pediatric Gastroenterology Hepatology and Nutrition Annual Meeting Oct. 21-23, 2011. J. Ped. Gastro. Nutr. 2011;53(1):E44.

A Novel Test for Eosinophilic Esophagitis (EoE) – The Esophageal String Test (EST)
Furuta GT, et al. North American Society for Pediatric Gastroenterology Hepatology, and Nutrition Annual Meeting (NASPGHAN), Oct. 21-23, 2011. J. Ped. Gastro. Nutr. 2011;53(1):E47.

Identification of Esophageal Microbiota in Eosinophilic Esophagitis and Gastrointestinal Reflux Disease
Fillon S, et al. 7th Biennial Symposium of the International Eosinophil Society, Inc. “Eosinophils 2011 – Forever Young.” June 21-25, 2011, Quebec City, Canada. Program and Abstracts, Poster Abstract E4, Page 144.

The Esophageal String Test (EST): A Novel Minimally Invasive Method for Measuring Esophageal Inflammation in Eosinophilic Esophagitis
Furuta GT, et al. 7th Biennial Symposium of the International Eosinophil Society, Inc. “Eosinophils 2011 – Forever Young.” June 21-25, 2011, Quebec City, Canada. Program and Abstracts, Poster Abstract E12, Page 153

The Esophageal String Test (EST): A Novel Minimally Invasive Method for Measuring Esophageal Inflammation in Eosinophilic Esophagitis (EoE). Gastroenterology
Furuta GT, et al. May, 2011; 140 (5, Supplement 1):S-187