ATCC has adapted four influenza strains to tissue culture (TC) using MDCK cells (ATCC^® CCL-34™). The new TC-adapted products include two swine-derived H1N1 viruses and two of the H3N2 subtype. These new TC-adapted products join three popular strains already available (Table 1).

While chicken embryos support the growth of almost all influenza viruses, MDCK cells are also widely used for TC adaptation of influenza viruses. The ATCC TC-adapted strains are produced in ATCC CCL-34 cells and can be propagated in that cell line (Figure 1).

Tissue culture-adapted viruses from ATCC Genuine Cultures:

• Eliminate the need for embryonated chicken eggs
• Propagate easier and faster
• Retain high viral titer as determined by plaque assay

Items highlighted in blue are newly added TC-adapted offerings.
 * Recommended by FDA for analytical sensitivity (LoD) studies (Draft Guidance for Industry and FDA Staff – Establishing the Performance Characteristics of In Vitro Diagnostic Devices for the Detection or Detection and Differentiation of Influenza Viruses. Docket Number FDA-2008-D-0095).

ATCC determines viral titers for TC-adapted strains by both TCID-50 and plaque assay. The plaque assay titers of our TC-adapted strains are consistently between 10⁴ and 10⁷ PFU/mL (Figure 2). 

Figure 2. Plaque assay for
ATCC VR-1679 at a 10^-5 dilution.

To download a full list of ATCC Influenza Research Materials, please click here.

ATCC Genuine Cultures provide the top-quality strains needed to maintain product quality and reputation. With ATCC Genuine Cultures, our customers can rely on:

• Polyphasic characterization
• Genotypic analysis to ensure authenticity
• Management of strain stocks using a proprietary seed system
• Cultures that can be passaged up to five more times
• Meticulous protocols for preservation and storage to ensure viability
• Robust Quality Systems including ISO 9001:2000, 17025:2005, and Guide 34:2000
• The widest selection of microbes available