I'm trying to understand how lupus (particularly SLE) develops due to immunodeficiencies. I've understood that it's a type 3 hypersensitivity (autoimmune disease), where immunocomplexes (of self antigenes and anti bodies) accumulate, and that the immune system fails to degrade these immunocomplexes. I've learned at uni that the antibodies have self affinity for intracellular components (such as DNA, proteins etc.), and that T cells have self affinity for the intracellular components, so they recognize self antigenes and trigger immune responses? And does this happen because T cells have not been presented for self intracellular molecules in the negative selection (and they're not presented for even healthy people), or is it because the T cells in SLE pasients are not presented with self intracellular molecules in negative selection (and this is standard, and they should be presented with self intracellular components). Can anyone explain the molecular and immunological explanation behind lupus? Thanks!!