Hologic Panther Fusion Controls
The Panther Fusion SARS-CoV-2 Assay is a real-time RT-PCR in vitro diagnostic test intended for the qualitative detection of RNA from SARS-CoV-2 isolated and purified from nasopharyngeal (NP) and oropharyngeal (OP) swab specimens obtained from individuals who meet COVID-19 clinical and/or epidemiological criteria. The Panther Fusion SARS-CoV-2 Assay is for use only under Emergency Use Authorization (EUA) in the US laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C.§263a, to perform high complexity tests.
Results are for the identification of SARS-CoV-2 RNA. The SARS-CoV-2 RNA is generally detectable in nasopharyngeal and oropharyngeal swab specimens during the acute phase of infection. Positive results are indicative of the presence of SARS-CoV-2 RNA, clinical correlation with patient history and other diagnostic information is necessary to determine patient infection status. Positive results do not rule out bacterial infection or co-infection with other viruses. Laboratories within the United States and its territories are required to report all positive results to the appropriate public health authorities.
Negative results do not preclude SARS-CoV-2 infection and should not be used as the sole basis for patient management decisions. Negative results must be combined with other clinical observations, patient history, and epidemiological information. The Panther Fusion SARS-CoV-2 Assay on the Panther Fusion system utilizes Open Access reagents and functionality and is intended for use by trained clinical laboratory personnel specifically instructed and trained in the operation of the Panther Fusion system and in vitro diagnostic procedures. The Panther Fusion SARS-CoV-2 Assay is only for use under the Food and Drug Administration’s Emergency Use Authorization. Summary and Explanation of the Test.
Coronaviruses are a large family of viruses that may cause illness in animals or humans. In humans, several coronaviruses are known to cause respiratory infections ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). The most recently discovered coronavirus, SARS-CoV-2, causes the associated coronavirus disease COVID-19.
This new virus and disease were unknown before the outbreak began in Wuhan, China, in December 2019.1 The most common symptoms of COVID-19 are fever, tiredness, and dry cough. Some patients may have aches and pains, nasal congestion, runny nose, sore throat, or diarrhea. These symptoms are usually mild and begin gradually. Some people become infected but don’t develop any symptoms and don’t feel unwell. The disease can spread through respiratory droplets produced when an infected person coughs or sneezes. These droplets land on objects and surfaces around the person.
Other people may acquire SARS-CoV-2 by touching these objects or surfaces, then touching their eyes, nose, or mouth. Person-to-person spread was subsequently reported outside Hubei province and in countries outside China, including in the United States.2 Some international destinations and the United States now have apparent community spread of SARS-CoV-2 that is not related to travel.
Principles of the Procedure
The Panther Fusion SARS-CoV-2 Assay involves the following steps: sample lysis, nucleic acid capture, elution transfer, and multiplex RT-PCR when analytes are simultaneously amplified and detected. Nucleic acid capture and elution takes place in a single tube on the Panther Fusion system. The eluate is transferred to the Panther Fusion system reaction tube containing the assay reagents. Multiplex RT-PCR is then performed for the eluted nucleic acid on the Panther
Fusion system.
Nucleic acid capture and elution: Prior to processing and testing on the Panther Fusion system, specimens need to be transferred to a Specimen Lysis Tube containing specimen transport media (STM) that lyses the cells, releases target nucleic acid, and protects them from degradation during storage.
The Internal Control-S (IC-S) is added to each test specimen and controls via the working Panther Fusion Capture Reagent-S (FCR-S). The IC-S in the reagent monitors specimen processing, amplification, and detection. Capture oligonucleotides hybridize to nucleic acid in the test specimen. Hybridized nucleic acid is then separated from the specimen in a magnetic field.
Wash steps remove extraneous components from the reaction tube. The elution step elutes purified nucleic acid. During the nucleic acid capture and elution step, the total nucleic acid is isolated from specimens.
Elution transfer and RT-PCR: During the elution transfer step, the eluted nucleic acid is transferred to a Panther Fusion reaction tube already containing oil and reconstituted master mix.
Target amplification occurs via RT-PCR. A reverse transcriptase generates a DNA copy of the target sequences. Target specific forward and reverse primers and probes then amplify targets while simultaneously detecting and discriminating multiple target types via multiplex RT-PCR. To safeguard against potential mutational drift in the SARS-CoV-2 genome, the Panther Fusion
SARS-CoV-2 Assay amplifies and detects two conserved regions of the ORF1ab gene in the same fluorescence channel.
The two regions are not differentiated and amplification of either or both regions leads to a fluorescence signal. The Panther Fusion system compares the fluorescence signal to a predetermined cut-off to produce a qualitative result for the presence or absence of the analyte. The analytes and the channel used for their detection on the Panther/Panther Fusion system are summarized in the table below.