Diagnostic Assays

TICRO boasts qualified, highly trained personnel combined with access to state-of-the-art facilities, including Immunohistochemistry, Flow Cytometry, and Imaging and Histology Core Facilities, to meticulously conduct experiments and assays according to study specifications.

A sample of our most commonly requested assays is provided below. Please contact us regarding additional diagnostic assays.

Antibody Viral Inhibition Assay / Microneutralization Assay

Assay to determine if an antibody sample can inhibit virus infection or replication in an in vitro assay. In brief, a confluent monolayer of MDCK cells on a 96-well plate is infected with dilutions of a virus. The dilution of the virus is known to infect the monolayer leading to the presence of countable viral plaques. Test compounds are then incubated with the virus prior to infection or after infection. One day after the MDCK cells have been infected, a primary antibody specific for the virus is used to detect infected cells. Viral foci which are visualized on an ImmunoSpot instrument. The resulting inhibition of viral foci in the 96-well plate is then used to calculate the inhibition within the original sample.

ELISA (Enzyme-linked immunosorbent assay)

Common laboratory technique used to measure the concentration of an analyte (usually antibodies or antigens) in solution. An ELISA is used to detect and quantify specific antigen-eliciting molecules involved in biological processes present in biological samples (i.e. plasma, serum, and cell extracts). In brief, a plate is coated with a primary antibody, which recognizes the antigen of the target molecule and bonds with it. A secondary antibody that is joined to an enzyme (horseradish peroxidase substrate - HRP) that catalyzes the reaction mixture, yielding a specific color, recognizes the antigen-antibody complex. The optical density of this color correlates to the amount of analyte present in the original sample.

Hemagglutination Inhibition Assay (HAI)

Assay used to measure the relative concentration of neutralizing antibodies to influenza virus isolated from either hybridoma tissue culture supernatants, mouse serum or in tissue homogenates. In brief, antibodies against the influenza HA protein bind to the antigenic sites on the HA protein of the influenza virus, these sites then become unavailable for subsequent binding and cross-linking with RBCs. This inhibition of hemagglutination effect by influenza virus is the basis for the HAI test.

Multi-Analyte Profiling (Luminex)

Multiplexing is a method for high-volume biomarker testing—or testing multiple analytes simultaneously within a single run—using a single sample volume. Pre-made kits utilizing microspheres or beads allow for the simultaneous capture of multiple analytes from a single reaction. The beads are individually read using an xMAP instrument. Typically cytokine and chemokine levels are analyzed at different timepoints during infectious disease modeling or therapeutic evaluation.

ELISpot (Enzyme-linked immune absorbent spot assay)

Immunoassay used to detect the presence of a particular analyte. By using specific antibodies matched for target molecules the frequency and total numbers of cells secreting antibodies, cytokines and other molecules can be determined and visualized as a ‘spot’ on a membrane. Variations of this assay can allow for the determination of antigen-specific memory B cells and the presence of plaque-forming virus. The number of ‘spots’ are captured and analyzed on a ELISpot plate reader.

RT-PCR (Reverse transcription-polymerase chain reaction)

Following RNA isolation, a technique combining the reverse transcription of RNA to DNA and the subsequent application of PCR in a sample to amplify specific sequences. The amount of RNA in a sample can be quantified using real-time or quantitative PCR (qPCR).

Nucleic Acid Sequencing

Following isolation of nucleic acid samples, sequencing data can be generated by TICRO through third-party providers.