CYTO-STAT TRICHROME CD45-FITC/CD4-RDI/CD3-PC5 MONOCLONAL ANITBODY REAGENT W/ISOTYPIC CONTROL by COULTER CORP.

CYTO-STAT® triCHROME™ CD45-FITC/CD4-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 CD4+ and dual-stained CD3+/CD4+ lymphocytes in whole blood by flow cytometry. An isotypic control, CYTO-STAT® triCHROME™ CD45-FITC/MsIgG1-RD1/MsIgG1-PC5, is used to monitor non-specific binding.

Device Description

AI/ML Overview

Here's a breakdown of the acceptance criteria and study information for the CYTO-STAT® triCHROME™ CD45-FITC/CD4-RD1/CD3-PC5 Monoclonal Antibody Reagent:

1. Table of Acceptance Criteria and Reported Device Performance

The provided summary does not explicitly define acceptance criteria as numerical thresholds for accuracy, linearity, or precision. Instead, it describes general performance goals (e.g., "met all performance specifications," "comparable to those of CD3/T4," "demonstrated linearity," "demonstrated precision"). The "Reported Device Performance" column thus describes the general findings.

Acceptance Criterion Type	Acceptance Criteria (Implicit)	Reported Device Performance
Accuracy	Identify and enumerate targeted lymphocytes in whole blood specimens, comparable to a predicate device (CD3/T4).	CD45/CD4/CD3 and CD3/T4 identify and enumerate essentially identical numbers of the targeted lymphocytes (CD3+, CD4+, and dual-stained CD3+/CD4+ percentages and absolute counts) in whole blood specimens. This was determined through regression and correlation analyses and analyses of variance between the two reagents.
Linearity	Maintain proportional response across a range of CD3+ and CD4+ lymphocyte concentrations.	Linearity of the assay was demonstrated by regression and correlation analyses of recovered versus expected absolute counts across serially diluted concentrated normal whole blood specimens.
Precision (Within-Day/Intralaboratory)	Consistent and reproducible results for lymphocyte concentrations within single-day testing.	Within day/intralaboratory precision of the assay was demonstrated through analysis of mean ± 1 SD and CV from 10 replicate measurements for three different levels of lymphocyte concentrations.
Precision (Interlaboratory)	Consistent and reproducible results for lymphocyte concentrations across different laboratories.	Interlaboratory precision of the assay was demonstrated through analysis of mean ± 1 SD and CV from 10 replicate measurements on a single specimen across different laboratories using different flow cytometers.

2. Sample Size Used for the Test Set and Data Provenance

Sample Size for Accuracy Test: The document states that "Normal and abnormal (e.g., Human Immunodeficiency Virus, organ transplant, autoimmune disesease, low white blood cell count) whole blood specimens were collected." It does not provide a specific numerical sample size.
Sample Size for Linearity Test: Three replicate measurements were made on "a concentrated normal whole blood specimen serially diluted" to achieve various concentrations. The number of unique patient samples used to create this concentrated specimen is not specified.
Sample Size for Precision (Within-Day/Intralaboratory) Test: Three levels of lymphocyte concentrations were obtained (likely from a single normal whole blood specimen through depletion), and "Ten replicate measurements were made for each of three levels," totaling 30 measurements.
Sample Size for Precision (Interlaboratory) Test: "Ten replicate measurements on were made on the same day using different laboratories" on "a single normal whole blood specimen."
Data Provenance: The specimens for accuracy testing were collected from "geographically diverse populations of males and females unselected as to race and ranging in age from 18 to 85 years." The study appears to be prospective in nature, as specimens were "collected" and "processed as lysed preparations and assayed."

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

This type of device (monoclonal antibody reagent for flow cytometry) does not typically involve expert readers establishing a "ground truth" in the way an imaging AI device might. The "truth" or reference standard for comparison is the predicate device's (CD3/T4) performance, and standard laboratory techniques for flow cytometry. The comparison is between two laboratory reagents/methods, not against a human interpretation of images. Therefore, this section is not applicable in the traditional sense. The "ground truth" is implied by the established methodology of flow cytometry and the performance of the predicate device.

4. Adjudication Method for the Test Set

Not applicable for this type of device. The comparison is objective (numerical results from flow cytometers) between the new device and a predicate device, not subjective interpretation requiring adjudication among experts.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

Not applicable. This is a laboratory reagent, not an AI-assisted diagnostic tool that would be used by human readers for interpretation.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done

The entire performance evaluation describes the standalone performance of the reagent and the associated flow cytometry system. The device (reagent) itself is not an "algorithm" in the AI sense, but its performance is measured independently. The results are generated by the instrument based on the reagent reaction, and then analyzed statistically.

7. The Type of Ground Truth Used

The "ground truth" for evaluating the performance of the CYTO-STAT® triCHROME™ CD45-FITC/CD4-RD1/CD3-PC5 reagent is defined by:

Comparison to a legally marketed predicate device: CYTO-STAT®/COULTER CLONE® CD3(IgG1)-FITC/T4-RD1 Monoclonal Antibody Reagent. The performance of the new reagent is directly compared against this established product.
Established flow cytometry principles and methodology: The measurements (percentages and absolute counts of lymphocyte populations) are determined by the COULTER® EPICS® XL/XL-MCL flow cytometers, which are standard in the field.
Clinical relevance: The ability to identify normal and abnormal (e.g., HIV, organ transplant) specimens implies a connection to clinical outcomes, though direct outcomes data for the reagent's performance is not detailed in this summary.

8. The Sample Size for the Training Set

Not applicable. This device is a diagnostic reagent, not an algorithm that requires a "training set" in the machine learning sense. Its performance is chemical/biochemical and instrument-based, not learned from data.

9. How the Ground Truth for the Training Set Was Established

Not applicable, as there is no training set for this type of device.

Summary

Regulation Number and Section

§ 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.”