Advancing Multiplexed Infectious Disease Diagnostics
Multiplexed solutions for accurate, rapid detection and management of infectious diseases
Focus: Development and commercialization of multiplexed products for the diagnosis of Infectious diseases, with an emphasis on tuberculosis (TB).
Approach: Instrument platform agnostic—we leverage the right instrumentation platform for the right diagnostic application, tailored to the needs of our target clinical markets.
Technology: Bead-based flow cytometric multiplex assays for simultaneous detection of multiple biomarkers.
Impact: Enabling better decisions in diagnosis, treatment selection, and treatment monitoring.
Technology
Our platform combines bead-based multiplex assays with flow cytometry to deliver highly sensitive diagnostics.
- Assay principle: Analytes such as proteins or nucleic acids are conjugated to distinct fluorescent microbeads. The conjugated microbeads are pooled and incubated with patient samples. Each bead population is identified by its unique fluorescent signature as it passes through a dual-laser flow cell or fluorescent imager.
- Detection: Simultaneous measurement of multiple biomarkers in a single sample.
- Scalability: Adaptable for both high-throughput testing and single-sample formats.
Pipeline
AppGenex Diagnostics is developing a portfolio of proteomic and molecular TB diagnostic solutions designed to support clinicians across the continuum of care—from initial screening and diagnosis to treatment selection and monitoring.
Multiplex TB Serodetection Test
The Multiplex TB Serodetection Test detects active TB disease in humans. This panel consists of multiple purified, recombinant pathogen antigens chemically cross-linked to fluorescently coded microbeads. This unique antigen combination is designed to deliver consistently high sensitivity and specificity for active TB detection.
- Multiple antigens for sensitivity: Multiple antigens are necessary to reach the required level of sensitivity, reducing false negatives and improving diagnostic confidence.
- Blood-based sampling: Using blood samples avoids the biohazard associated with infectious sputum and supports detection in cases where sputum collection is difficult or not possible.
- Single-tube efficiency: Testing can be performed in a single tube or well using small sample volumes.
- Sample flexibility: Detects antibodies in blood targeting M.tb antigens, indicative of active TB. Requires only a few drops of blood, which can be processed directly or applied to filter paper as dried blood spots (DBS).
- Field-ready sampling: DBS enable simple sample collection in remote or resource-limited settings (e.g., refugee camps, rural villages) by healthcare workers or trained field staff.
- Clinical coverage: Detects multiple forms of active TB, including:
- Adult pulmonary TB
- Extrapulmonary TB (non-sputum specimen cases)
- Pediatric TB (difficult sputum collection)
- Clinically diagnosed cases that test negative by traditional methods
- Status: This test is under review by the Indian Council for Medical Research.
Multiplex MDR-TB Panel
The Multiplex MDR-TB Test is a molecular diagnostic panel intended for patients who test positive on the Multiplex TB Serodiagnostic Panel. It is designed to detect multidrug-resistant TB (MDR-TB) and support selection of the most appropriate antibiotics for treatment.
- Multiple single-stranded nucleic acid probes: Multiple single-stranded nucleic acid probes specific to target mutations in genes associated with drug resistance are cross-linked to microbeads, enabling detection and prediction of resistance to first-line drugs in infected individuals.
- ·Clinical coverage: Developed to detect resistance to four main drugs used for the initial treatment of TB (rifampin, isoniazid, ethambutol, and streptomycin)
- ·Need: Growing numbers of MDR-TB cases are emerging as a result of TB treatment mismanagement. Identifying MDR-TB status can support more effective and cost-effective treatment.
- Status: In development
Multiplex TB Treatment Response Panel
The Multiplex TB Treatment Response Test tracks key biomarkers in the blood of TB patients that correlate with antibiotic treatment success and is designed to help predict treatment efficacy.
- Antibodies specific to blood-based biomarkers: The assay consists of antibodies specific to blood-based biomarkers cross-linked to microbeads.
- Clinical coverage: Tracks immunomodulatory biomarker levels that correlate with TB treatment success. A decrease in biomarker concentration is indicative of treatment success.
- Need:Treatment success and patient adherence can be difficult to assess. Better visibility into treatment response may help prevent the emergence of MDR-TB.
- Status: In development.
TB-Plex assay for Nonhuman Primates
The TB-Plex assay (in partnership with Charles River Laboratories) is a high-throughput bead-based immunoassay used to screen nonhuman primate (NHP) serum and plasma for antibodies to M.tb.
- Technology: Uses Luminex flow cytometry technology to simultaneously measure the fluorescent signal of beads coupled with multiple different TB antigens.
- Colony management: TB is highly contagious and potentially fatal in NHPs. Serological assays like TB-Plex are critical for routine health surveillance, pre-export testing, and managing specific pathogen-free (SPF) colonies.
- Status: Commercialized by Charles River Laboratories, the product was launched in 2018.