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GTR Home > > Ethos Laboratories Tru Immune


Test order codeHelp: AB300

Test name


Ethos Laboratories Tru Immune

Purpose of the test


This is a clinical microbial test intended for Help: Diagnosis, Screening



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How to order


By Healthcare Provider via online portal. CPT Code: 0226U

Specimen source

Peripheral (whole) blood

Sample requirements

Blood is drawn in a lavender top tube containing EDTA by a qualified phlebotomist from a patient that SARS CoV-2 antibody testing has been ordered by a Healthcare Provider. The blood tube is labeled with two (2) patient identifiers. The test requisition form or electronic requisition form is filled out by the collector. The blood tube is secured in the proper shipping container to be shipped to the laboratory for testing. Once received at the laboratory the shipping container is placed in a secure area and opened by laboratory staff, using proper PPE, under a biosafety cabinet located in a biosafety level two laboratory.


OAntibody assay
Antibody detection
  • Dynex DSX automated ELISA platform
  • Tru-Immune SARS-CoV-2 Neutralizing Antibody ELISA test

Summary of what is tested

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Clinical utility


Establish or confirm diagnosis

  • Validation and clinical evaluation of a SARS-CoV-2 surrogate virus neutralisation test (sVNT). - PubMed ID: 33043818

Clinical validity


Seventy-seven (77) presumed true negative samples that had been collected prior to the onset of the emergence of COVID-19 pandemic were also randomized before sending to the clinical laboratory for testing. All one-hundred and seven (107) samples were assayed using the Tru-Immune SARS-CoV-2 Neutralizing Antibody ELISA Test and all absorbance readings at 450nm were converted to %Inhibition values based on the equation previously described. Any %Inhibition value > 20% Inhibition was reported as positive and all values < 20% were reported as negative. PCR+ samples were 100.0% positive by the Tru-Immune SARS-CoV-2 Neutralizing Antibody ELISA Test and all negative samples returned a negative result for 100% negative agreement. Results are shown in the table below: SARS-CoV-2 PCR Status Neutralizing Antibody ELISA Test Positive Negative Total Positive 30 0 30 Negative 0 77 77 Total 30 77 107 Percent Positive Agreement (Sensitivity) = TP/(TP+FN) =100% Percent Negative Agreement (Specificity) = TN/ (TN+FP)= 100%


Not provided

Comments about the test interpretation (e.g. clinical implication of test results)

POSITIVE RESULT A positive test result with the Tru-Immune SARS-CoV-2 Neutralizing Antibody ELISA test indicates that functional antibodies capable of neutralizing or inhibiting the SARS-CoV-2 virus were detected in the specimen. This result indicates that the individual has potentially been exposed to COVID-19 and has produced antibodies that are now capable of blocking the interaction between the virus and its target receptor (ACE2). The Tru-Immune SARS-CoV-2 Neutralizing Antibody ELISA test is isotype independent meaning that it can detect the inhibition capacity of all neutralizing antibodies (e.g., IgG, IgM) present in the sample. Positive test results indicate that neutralizing antibodies were detected in the specimen. Semi-quantitative results will be provided which describe the capacity of detected antibodies to block the SARS-CoV-2/ACE2 interaction. Blocking capacity of detected antibodies will be reported as a percentage (%) where the higher the result, the greater the inhibition capacity of the neutralizing antibodies. Neutralizing antibodies to SARS-CoV-2 generally do not begin to appear until 2-10 days after infection. When neutralizing antibodies are present, it often indicates a past infection but does not exclude recently infected individuals who are still contagious. It is unknown how long neutralizing antibodies to SARS-CoV-2 will remain present in the body after infection. Neutralizing antibodies are the best way to evaluate protective immunity to infection, however the duration of this protection is currently unknown. A positive result for neutralizing antibodies may not mean that an individual’s current symptoms are due to COVID-19 infection. Laboratory test results should always be considered in the context of clinical observations and epidemiological data to guide patient management decisions. The Tru-Immune SARS-CoV-2 Neutralizing Antibody ELISA test has been designed to minimize the likelihood of false positive results. However, in the event of a false positive result, immediate measures to consider could include the following: a recommendation for isolation of the individual, monitoring of household or other close contacts for symptoms, isolation that might limit contact with family, friends, or other potentially COVID-19 infected individuals, limits in the ability to work, or other unintended adverse effects. All laboratories using this test must follow standard confirmatory testing and reporting guidelines according to their appropriate public health authorities. NEGATIVE RESULT A negative test result with this test means that SARS-CoV-2 neutralizing antibodies were not present in the specimen above the limit of detection. However, a negative result does not preclude COVID-19 infection and should not be used as the sole basis for treatment, patient management decisions, or to rule out active infection. Individuals tested early after infection may not have detectable neutralizing antibody despite active infection; in addition, not all individuals will develop a detectable neutralizing response SARS-CoV-2 infection. The absolute sensitivity of the Tru-Immune SARS-CoV-2 Neutralizing Antibody ELISA test is unknown. When diagnostic testing is negative, the possibility of a false negative should be considered in the context of an individual’s recent exposures and the presence of clinical signs and symptoms consistent with COVID-19. This is especially important if the individual has had recent exposure to COVID-19, or clinical presentation suggestive of COVID-19, and diagnostic tests for other causes of illness (e.g., other respirator illness) are negative. Direct testing for virus (e.g., RT-PCR testing) should always be performed in any individual suspected of COVID-19, regardless of the Tru-Immune SARS-CoV-2 Neutralizing Antibody ELISA test result. Risks to an individual of a false negative result include: restriction of activities deemed appropriate for individuals with evidence of a neutralizing antibody response to SARS-CoV-2, or other unintended adverse events.

Test services

  • Result interpretation, Order code: VR100

Clinical resources

Practice guidelines

  • NICE, 2022
    UK NICE Guideline NG191, COVID-19 rapid guideline: managing COVID-19

Consumer resources

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