Tissue Culture for Viral Isolation

Tissue culture involves the inoculation of patient specimens into live cells to allow for viral replication, which can then be detected through

cytopathic effects (CPE), immunostaining, or molecular methods

Cells freshly isolated from human or animal tissue that retain normal diploid chromosome content but are short-lived.

Primary Cell Cultures

Primary Cell Cultures

Primary Rabbit Kidney

Primary Monkey Kidney

Primary Human Embryonic Kidney (HEK)

Primary Rabbit Kidney is Used for:

Herpes Simplex Virus (HSV) types 1 and 2

High sensitivity but limited availability.

Primary Rabbit Kidney

Primary Monkey Kidney is Used for:

• Influenza A & B

• Parainfluenza (Types 1, 2, 3)

• Mumps, Measles, Rubella

• Enteroviruses

Primary Human Embryonic Kidney (HEK) is Used for:

• Parainfluenza, Measles, Rubella

• Adenoviruses, Rhinoviruses

• HSV 1 & 2, Varicella Zoster Virus (VZV)

While primary cells are still used for some virus types, many labs now prefer

immortalized or genetically engineered cell lines due to standardization, longer shelf-life, and fewer contamination risks.

Cell Lines (Derived from primary cultures)

1. Diploid Cell Lines

2. Heteroploid (Continuous) Cell Lines

Cells with stable chromosome complement

Diploid Cell Lines

Diploid Cell Lines senesce after

30–50 passages.

Diploid Cell Lines

• WI-38, MRC-5, IMR-90

Human fibroblast lines

WI-38, MRC-5, IMR-90

WI-38, MRC-5, IMR-90 are best for

Cytomegalovirus (CMV), HSV, Rubella

Have abnormal karyotypes and can replicate indefinitely.

Heteroploid (Continuous) Cell Lines

Heteroploid (Continuous) Cell Lines are Common choices for

high-throughput and routine viral culture.

These cell lines are immortalized and can divide indefinitely, making them valuable tools for virology laboratories.

Heteroploid (Continuous) Cell Lines

They typically have abnormal chromosome numbers and are derived from human carcinomas.

Heteroploid (Continuous) Cell Lines

List Heteroploid (Continuous) Cell Lines

A549 Cells

HEp-2 Cells

HeLa Cells

Origin: Human lung carcinoma (adenocarcinoma)

A549 Cells

A549 Cells Key Viruses Cultured

Adenoviruses

Varicella Zoster Virus (VZV)

A549 Cells are Also used for

influenza, SARS-CoV-2, and

Origin: Human laryngeal carcinoma

HEp-2 Cells

HEp-2 Cells Key Viruses Cultured:

Respiratory Syncytial Virus (RSV)

Adenoviruses

HEp-2 Cells Show clear cytopathic effect (CPE) in these cells.

Adenoviruses

Often used in direct fluorescent antibody (DFA) testing for RSV.

HEp-2 Cells

Origin: Human cervical adenocarcinoma

HeLa Cells

HeLa Cells Key Viruses Cultured:

• Respiratory Syncytial Virus (RSV)

• Rhinoviruses

• Adenoviruses

robust, fast-growing, and one of the oldest human cell lines used in laboratories globally.

HeLa cells

are now commonly used in shell vial cultures and automated immunofluorescence platforms.

A549 and HEp-2

preferred for RSV culture and antigen detection.

HEp-2

Order of Inoculation

1. Diploid cell lines inoculated first (e.g., MRC-5)

2. Then heteroploid/continuous lines (e.g., A549, HeLa)

3. Primary cells inoculated last due to fragility and higher cost