Development of EndoScreen Chip, a Microfluidic Pre-Endoscopy Triage Test for Esophageal Adenocarcinoma

SIMPLE SUMMARY: Esophageal adenocarcinoma (EAC) is often detected late and has a poor survival rate. Currently, patients are selected for endoscopy-biopsy diagnosis based on clinical risk factors such as the precursor condition Barrett’s esophagus, history heartburn/reflux, age and high body mass index. To enable blood-based screening, we previously discovered and validated novel blood biomarkers for early stage EAC. To support clinical application, here, we report the technology development of the microfluidic EndoScreen chip and validation using the biomarker JAC-C9 (Jacalin-lectin binding complement component C9) in a test cohort of 46 samples. Compared to clinical risk factors alone, we found that use of blood biomarkers JAC-C9 and total C9 in addition to clinical risk factors improved EAC prediction in this cohort, suggesting that a simple blood test can help the physician prioritize patients for endoscopic evaluation. Future work will deploy a panel of markers on a point-of-care version of EndoScreen chip, to enable population screening and early diagnosis of EAC and thereby reduce mortality from this cancer. ABSTRACT: The current endoscopy and biopsy diagnosis of esophageal adenocarcinoma (EAC) and its premalignant condition Barrett’s esophagus (BE) is not cost-effective. To enable EAC screening and patient triaging for endoscopy, we developed a microfluidic lectin immunoassay, the EndoScreen Chip, which allows sensitive multiplex serum biomarker measurements. Here, we report the proof-of-concept deployment for the EAC biomarker Jacalin lectin binding complement C9 (JAC-C9), which we previously discovered and validated by mass spectrometry. A monoclonal C9 antibody (m26 3C9) was generated and validated in microplate ELISA, and then deployed for JAC-C9 measurement on EndoScreen Chip. Cohort evaluation (n = 46) confirmed the expected elevation of serum JAC-C9 in EAC, along with elevated total serum C9 level. Next, we asked if the small panel of serum biomarkers improves detection of EAC in this cohort when used in conjunction with patient risk factors (age, body mass index and heartburn history). Using logistic regression modeling, we found that serum C9 and JAC-C9 significantly improved EAC prediction from AUROC of 0.838 to 0.931, with JAC-C9 strongly predictive of EAC (vs. BE OR = 4.6, 95% CI: 1.6–15.6, p = 0.014; vs. Healthy OR = 4.1, 95% CI: 1.2–13.7, p = 0.024). This proof-of-concept study confirms the microfluidic EndoScreen Chip technology and supports the potential utility of blood biomarkers in improving triaging for diagnostic endoscopy. Future work will expand the number of markers on EndoScreen Chip from our list of validated EAC biomarkers.