What substance do you use to viruses grow in a laboratory?

Viruses are obligate intracellular parasites, meaning they can only replicate inside the cells of a host organism. In a laboratory setting, viruses are typically grown in cell cultures, which are prepared from living cells that have been isolated from an organism. The specific type of cell culture used depends on the virus being studied. For example, some viruses can only grow in certain types of cells, such as human cells or animal cells.

The process of growing viruses in cell cultures involves several steps:

1. Obtaining the virus: The first step is to obtain the virus that you want to study. This can be done by isolating the virus from an infected organism, such as a human patient or an animal. Alternatively, the virus can be obtained from a laboratory stock.

2. Preparing the cell culture: The next step is to prepare the cell culture. This involves obtaining the appropriate type of cells and growing them in a culture medium that provides the cells with the nutrients they need to survive. The culture medium is typically supplemented with serum, which contains growth factors that help the cells to grow.

3. Infecting the cells: Once the cell culture is prepared, the virus is introduced into the culture. This can be done by adding the virus directly to the culture medium, or by using a technique called transfection. Transfection involves introducing the virus into the cells using a chemical agent or a physical method.

4. Incubation: After the cells have been infected with the virus, the culture is incubated at a suitable temperature and humidity. This allows the virus to replicate inside the cells. The incubation period can vary depending on the virus being studied.

5. Harvesting the virus: Once the virus has replicated to a sufficient level, the virus is harvested from the cell culture. This can be done by collecting the culture medium and centrifuging it to remove the cells. The supernatant, which contains the virus, is then collected and stored.

The virus that has been harvested from the cell culture can then be used for further studies, such as characterization, purification, or vaccine development.