What type of testing involves isolating the virus from macrophages for ASF diagnosis?

In the context of diagnosing African Swine Fever (ASF), isolating the virus from macrophages is best achieved through cell culture techniques. This method involves inoculating macrophage cultures with a sample suspected of containing the ASF virus. If the virus is present, it will replicate within the macrophages, allowing for its detection and further analysis.

Cell culture is a critical technique for viral isolation because it provides a controlled environment where viruses can grow and be studied in detail. It also allows for the observation of cytopathic effects, which are changes in the infected cells that can indicate the presence of a virus. This approach is particularly important for viruses like ASF that can be challenging to detect using other methods.

The other options play different roles in diagnostic processes but do not typically involve isolating the virus directly from cells. Sero-diagnostic assays are used to identify antibodies in the serum, antigen detection focuses on identifying viral proteins, and genetic sequencing involves analyzing the virus's genetic material to identify the pathogen. Each of these methods can be useful in conjunction with cell culture but does not specifically involve isolating the virus from macrophages.