Microbiology

QFT-Plus is an IFNγ release assay, commonly known as an IGRA, and measures the cell-mediated immune response to specific TB antigens in whole blood. It is optimized with innovative CD8 T cell technology, providing a more comprehensive view of the immune response to TB infection.

The test employs standard phlebotomy procedures using whole blood to make sample collection easy and fast. Sample incubation can occur on-site or at the testing laboratory, providing your practice with complete flexibility and convenience. Patients may be tested in a single patient visit, with objective results.

Features:
– High sensitivity (>94%) and specificity (>97%)
– Objective and controlled laboratory assay
– Innovative CD8 T cell technology
– Unaffected by BCG vaccination
– Robust and reliable results
– Industry leading flexible blood collection options
– More cost effective than TST when multiple screening

Procedure
The QFT-Plus test is a straightforward laboratory TB blood test that involves the following steps:

1. Collect whole blood, using one of two options:
– Direct draw: Collect 1 ml of whole blood directly into each of four QFT-Plus blood collection tube and hold at room temperature for up to 16 hours prior to incubation.
– Single lithium-heparin tube: Draw at least 5 ml of blood into a single blood collection tube containing lithium-heparin as the anticoagulant. Blood collected into a single lithium-heparin tube may be stored at room temperature or refrigerated for up to 53 hours prior to transfer to QFT-Plus tubes and incubation.
– Note: QFT-Plus has 4 blood collection tubes: Nil, TB1, TB2, and Mitogen. Collect 1 ml of whole blood into each tube.
2. Incubate for 16 to 24 hours at 37°C.
3. Detect released IFNγ in harvested plasma by ELISA.
4. Analyze results using QFT-Plus Analysis Software.

QIAGEN QuantiFERON-TB Gold Plus ELISA Kit: 2 sets of 12 x 8 Microplate Strips; IFN-gamma Standard, lyophilized; Green Diluent; Conjugate 100x Concentrate, lyophilized; Wash Buffer 20x Concentrate; Enzyme Substrate Solution; Enzyme Stopping Solution

QIAGEN QuantiFERON-TB Gold Plus Collection Tubes: 200 QFT-Plus Blood Collection Tubes (50 each: Nil, TB1, TB2 and Mitogen tubes)