ANA seen in SLE is directed against?
“Antibodies to double-stranded DNA and the Smith (Sm) antigen are virtually diagnostic of SLE" ---------- Robbins
Antinuclear antibodies in SLE
1) Generic antinuclear antibodies (ANA)
□ These are most common (93-100% of patients), thus are most sensitive antibodies for SLE (best screening test).
2) Anti-dsDNA and Anti-smith (Sm) antibodies
□ These are the most specific antibodies for SLE.
3) Antihistone antibodies
□ Particularly seen in drug-induced SLE.
4) Anti-RNP SS-A (Ro), SS-B (La)
□ These are seen in neonatal lupus with congenital heart block and in subacute cutaneous lupus. These antibodies are associated with decreased risk of lupus nephritis.
5) Other less common types of ANAs in SLE
□ Anti-U1 RNP
□ Anti-DNA topoisomerase (Scl-70)
□ Anticentromere
□ Anti-histidyl t-RNA synthase
dsDNA
mRNA
Nucleolus
Ribosomes