IMMUNE CELL FUNCTION ASSAY
Device Facts
| Record ID | K013169 |
|---|---|
| Device Name | IMMUNE CELL FUNCTION ASSAY |
| Applicant | Cylex, Inc. |
| Product Code | NID · Hematology |
| Decision Date | Apr 2, 2002 |
| Decision | SESE |
| Submission Type | Traditional |
| Regulation | 21 CFR 864.5220 |
| Device Class | Class 2 |
| Attributes | Real-World Evidence |
Real-World Evidence
| Submission | Device | Sponsor | RWD Sources | RWE Use Summary | Key Tags |
|---|---|---|---|---|---|
| K013169 · Apr 2, 2002 | IMMUNE CELL FUNCTION ASSAY | Cylex, Inc. | Clinical cohort of transplant recipients; Clinical cohort of apparently healthy adults | The study evaluated the Cylex Immune Cell Function Assay in a multi-center clinical setting to compare ATP concentration results between immunosuppressed transplant patients and healthy controls, establishing clinical performance characteristics. | Transplant recipients; Immunosuppressive therapy; Multi-center study; Clinical performance |
Clinical Evidence
| Study Design | Population | Comparator | Key Endpoints |
|---|---|---|---|
| Multi-center study of Cylex Immune Cell Function Assay; Multi-center clinical evaluation | 78 transplant recipients (immunosuppressed) and 44 apparently healthy adults; Sample Size: 122 total (63 transplant subjects and 40 healthy adults included in final analysis) | Becton Dickinson TriTest/MultiTest CD4 count by flow cytometry | ATP concentration (ng/mL) as an indicator of immune cell function |
Indications for Use
The Cylex Immune Cell Function Assay measures the concentration of ATP from circulating CD4 cells following in vitro stimulation with phytohemagglutinin (PHA) as an indicator of immune cell function. This measurement is made on heparin anticoagulated whole blood using a luminometer and luciferin/luciferase. The assay is used for the detection of cell mediated immune response in populations undergoing immunosuppressive therapy for organ transplant.
Device Story
Device measures ATP concentration in CD4 cells to assess cell-mediated immune function. Input: heparin-anticoagulated whole blood. Process: in vitro stimulation with phytohemagglutinin (PHA) triggers ATP synthesis in responsive cells; antibody-coated magnetic particles immunoselect CD4 cells; lysis reagent releases intracellular ATP; luciferase-luciferin reaction produces light proportional to ATP concentration. Output: light measurement (emission max 562 nm) via luminometer, converted to ATP concentration (ng/mL) using calibration curve. Used in clinical laboratory settings by trained personnel. Results assist clinicians in evaluating immune status of transplant patients on immunosuppressive therapy, potentially aiding in management of immunosuppression.
Clinical Evidence
Multi-center study of 44 healthy adults and 78 transplant recipients. Evaluated Cylex ICF Assay vs. flow cytometry CD4 counts. Results showed statistically significant differences between healthy and transplant populations for both assays (p < 0.0001). Mean ATP levels were 464 ng/mL (healthy) vs. 304 ng/mL (transplant).
Technological Characteristics
Uses antibody-coated magnetic particles for CD4 cell immunoselection. Detection via bioluminescence (luciferin/luciferase reaction) measured by luminometer (562 nm emission). Requires heparin-anticoagulated whole blood. Standalone assay system.
Indications for Use
Indicated for the detection of cell-mediated immunity in immunosuppressed populations, specifically those undergoing immunosuppressive therapy for organ transplant.
Regulatory Classification
Identification
An automated differential cell counter is a device used to identify one or more of the formed elements of the blood. The device may also have the capability to flag, count, or classify immature or abnormal hematopoietic cells of the blood, bone marrow, or other body fluids. These devices may combine an electronic particle counting method, optical method, or a flow cytometric method utilizing monoclonal CD (cluster designation) markers. The device includes accessory CD markers.
Special Controls
*Classification.* Class II (special controls). The special control for this device is the FDA document entitled “Class II Special Controls Guidance Document: Premarket Notifications for Automated Differential Cell Counters for Immature or Abnormal Blood Cells; Final Guidance for Industry and FDA.”
Predicate Devices
- Becton Dickinson TriTest™ CD4 FITC/CD8 PE/CD3 PerCP Reagent (K971205)
- Becton Dickinson MultiTest™ CD3 FITC/CD8 PE/CD45 PerCP/CD4 APC Reagent (K974360)