A blood-based prognostic biomarker in IBD.

Area of Science:

• Immunology
• Genetics
• Gastroenterology

Background:

• Previously identified a CD8 T cell transcriptional signature separating inflammatory bowel disease (IBD) patients into IBD1 and IBD2 subgroups.
• A need exists for a clinically applicable blood-based test to identify these subgroups without complex cell separation procedures.

Purpose of the Study:

• To develop and validate a blood-based gene expression classifier for identifying IBD subgroups in Crohn's disease (CD) and ulcerative colitis (UC).
• To assess the prognostic value of this classifier in predicting disease aggressiveness and treatment escalation.

Main Methods:

• Transcriptomic analysis of CD8 T cells and whole blood from IBD patients.
• Machine learning algorithms used to identify and optimize a 17-gene quantitative PCR (qPCR) classifier from whole blood samples.
• Independent validation of the qPCR classifier in separate cohorts of CD and UC patients.

Main Results:

• The 17-gene qPCR classifier successfully stratified patients into two distinct subgroups (IBDhi and IBDlo) in independent validation cohorts.
• IBDhi patients (analogous to IBD1) showed significantly more aggressive disease, with earlier and more frequent treatment escalations compared to IBDlo patients (analogous to IBD2).
• High sensitivity and negative predictive values were observed for predicting treatment escalation within 18 months.

Conclusions:

• This study presents the first validated prognostic biomarker for predicting outcomes in newly diagnosed IBD patients.
• The developed blood-based test offers a practical tool for identifying patient subgroups and guiding personalized therapeutic strategies in IBD.
• This biomarker represents a significant advancement towards personalized medicine in the management of IBD.