(203 days)
CYTO-STAT® triCHROME™ CD45-FITC/CD8-RD1/CD3-PC5 is a three-color fluorescent reagent comprised of three murine monoclonal antibodies. Each antibody is labeled with a different color fluorochrome. The reagent identifies a lymphocyte gate based on CD45 staining (vs. side scatter) and allows simultaneous identification and enumeration of total CD3+, total CD8+ and dual-stained CD3+/CD8+ lymphocytes in whole blood by flow cytometry. An isotypic control, CYTO-STAT® triCHROME™ CD45-FITC/MsIgG1-RD1/MsIgG1-PCS, is used to monitor non-specific binding.
CYTO-STAT® triCHROME™ CD45-FITC/CD8-RD1/CD3-PC5 Monoclonal Antibody Reagent With Isotypic Control. A three-color fluorescent reagent comprised of three murine monoclonal antibodies. Each antibody is labeled with a different color fluorochrome.
The provided text describes the performance testing for the CYTO-STAT® triCHROME™ CD45-FITC/CD8-RD1/CD3-PC5 Monoclonal Antibody Reagent. Here's an analysis based on your request:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state numerical acceptance criteria in a dedicated section. However, it describes how performance was assessed and the general conclusion for each category. Based on the text, the acceptance criteria are implicitly that the product "met all performance specifications" and provided "comparable" results to the predicate device.
| Performance Characteristic | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Accuracy | Identify and enumerate targeted lymphocytes in whole blood specimens, comparable to CD3/T8 predicate device. | "Results analyzed in terms of minimums, maximums, means ± 1 SD, regression and correlation analyses, and analyses of variance demonstrated that CD45/CD3 and CD3/78 identify and enumerate essentially identical numbers of the targeted lymphocytes in whole blood specimens." (Note: CD45/CD3 is shorthand for CYTO-STAT® triCHROME™ CD45-FITC/CD8-RD1/CD3-PC5 and CD3/T8 for the predicate device). |
| Linearity | Demonstrate linearity of the assay for recovered vs. expected absolute counts of CD3+ (CD3+/CD3+/CD8+) lymphocyte concentrations. | "Results analyzed in terms of regression and correlation analyses for recovered versus expected absolute counts demonstrated linearity of the assay." |
| Precision (Within Day) | Demonstrate within-day/intralaboratory precision (mean ± 1 SD and CV) for CD3+ and CD8+ (CD3+/CD8+) lymphocyte concentrations. | "Results analyzed in terms of mean ± 1 SD and CV demonstrated within day/intralaboratory precision of the assay." |
| Precision (Interlaboratory) | Demonstrate interlaboratory precision (mean ± 1 SD and CV) for CD3+ and CD8+ (CD3+/CD8+) lymphocyte concentrations across different laboratories. | "Results analyzed in terms of mean ± 1 SD and CV demonstrated interlaboratory precision of the assay." |
2. Sample Size Used for the Test Set and Data Provenance
- Accuracy Test Set Sample Size: "Normal and abnormal (e.g., Human Immunodeficiency Virus, organ transplant, autoimmune diseases, low white blood cell count) whole blood specimens were collected..." The exact number of specimens is not specified.
- Linearity Test Set Sample Size: "Three replicate measurements were made on a concentrated normal whole blood specimen serially diluted to achieve a range of ten CD3+ (CD3+/CD3+/CD8+) lymphocyte concentrations." This implies at least 30 measurements (3 replicates x 10 dilutions) from a single specimen source.
- Precision (Within Day) Test Set Sample Size: "Ten replicate measurements were made for each of three levels of CD3+ and CD8+ (CD3+/CD8+) lymphocyte concentrations..." This suggests 30 measurements (10 replicates x 3 levels) on selectively depleted normal whole blood specimens.
- Precision (Interlaboratory) Test Set Sample Size: "Ten replicate measurements on were made on the same day using different laboratories..." "All measurements were made on a single normal whole blood specimen divided and assayed with CD45/CD8/CD3." This implies 10 measurements per laboratory, with the number of laboratories not explicitly stated beyond "different laboratories."
- Data Provenance:
- Accuracy: Specimens were collected from "geographically diverse populations of males and females unselected as to race and ranging in age from 18 to 85 years." The document does not specify the country of origin but states "geographically diverse." The data appears to be prospective as specimens were collected specifically for this testing.
- Linearity & Precision: These involved manipulation of "normal whole blood specimen" or "concentrated normal whole blood specimen," suggesting controlled laboratory experiments rather than direct patient samples for the test set.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This information is not applicable as the device is a diagnostic reagent for flow cytometry, not an image-based AI device requiring human expert adjudication for ground truth. The "ground truth" here is the established method of lymphocyte enumeration by flow cytometry using a comparable predicate device (CD3/T8) and the inherent biological characteristics of the samples.
4. Adjudication Method for the Test Set
This is not applicable for the reasons stated above.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done
This is not applicable as this is not an image-based AI device where human readers are involved in interpretation. The comparison is between two reagent assays for flow cytometry.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
This is not applicable in the context of an algorithm. However, the performance reported for accuracy, linearity, and precision represents the standalone performance of the reagent and flow cytometer system to identify and enumerate lymphocytes. Human involvement would be in sample preparation, running the flow cytometer, and data analysis software operation, but not in "reading" or "interpreting" like an AI model.
7. The Type of Ground Truth Used
The "ground truth" for evaluating the new reagent's performance is established by:
- Comparison to a Predicate Device: The accuracy study directly compares the results of the new CD45/CD8/CD3 reagent with those obtained from the predicate device, CYTO-STAT®/COULTER CLONE® CD3(IgG1)-FITC/T8-RD1 Monoclonal Antibody Reagent (K922744). The predicate device's established performance serves as the reference for "truth."
- Biological Expectations/Mathematical Models: For linearity, the ground truth is based on expected absolute counts from serial dilutions. For precision, the ground truth relates to the reproducibility of the measurements from a given sample.
8. The Sample Size for the Training Set
This product is a chemical reagent, not an AI model requiring a "training set" in the machine learning sense. Therefore, this information is not applicable.
9. How the Ground Truth for the Training Set was established
As there is no "training set" for this type of medical device (reagent), this question is not applicable.
§ 864.5220 Automated differential cell counter.
(a)
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.(b)
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.”