Staphylococcal protein A coated with antiserum is utilized in which serological test for cerebrospinal fluid?

Staphylococcal protein A coated with antiserum is primarily utilized in coagglutination tests because this method directly leverages the ability of protein A to bind immunoglobulins. In these tests, the antiserum is attached to the protein A on the surface of Staphylococcus aureus, enhancing its ability to agglutinate bacteria that have the corresponding antigens present in the test sample, such as cerebrospinal fluid.

Coagglutination tests are useful for identifying specific pathogens in clinical samples by detecting the presence of antigen-antibody complexes. The binding of the antigen in the cerebrospinal fluid to the antibodies on the protein A-coated Staphylococcus leads to visible clumping, indicating a positive result. This technique is advantageous in a clinical setting for rapid diagnosis and is particularly effective for certain types of bacterial meningitis.

While other options involve serological reactions, they do not utilize protein A in the same manner as coagglutination tests. For instance, latex agglutination tests typically use latex beads that are coated with antibodies, and counterimmunoelectrophoresis involves the simultaneous application of antigens and antibodies in an electric field, which does not include the use of Staphyloc