When we generally speak of the immune response to viral infections, we talk of neutralising antibodies. These are antibodies that can neutralise the effect of the virus and reduce its load.
My question is, what do the rest of the antibodies produced, which are not neutralising, even do?
Is it a failure of the immune response of the body to produce antibodies that are not neutralising? But isn't binding enough for opsonisation?
How is 'neutralising' even defined? Are such antibodies neutralising just based on binding (since I assume neutralisation assays are in-vitro) or do even these antibodies require downstream antibody effector mechanisms like complement, opsonisation, ADCC etc. for neutralisation?