Characteristic Nucleolar-Reticular Immunofluorescence Staining Pattern on Touch Prints of Hamster Liver: A Marker for Scl-70 Antibody

Abstract

Sera from 48 patients with systemic sclerosis (SSc) and from 62 patients with other connective tissue diseases were studied for nuclear staining patterns by indirect immunofluorescence (IIF) using touch prints of hamster liver, HEp-2 and cryostat sections of monkey esophagus as substrates. Immunodiffusion studies performed in all cases disclosed Scl-70 antibody in 36 SSc patients. The IIF pattern of Scl-70 antibody is characterized by diffuse granular and nucleolar staining on HEp-2, a combined nucleolar and diffuse reticular staining on imprints of hamster liver and large speckled (nucleolar) fluorescence on cryostat sections of monkey esophagus. Touch prints of hamster liver revealed a partially nucleolar fluorescence as a dominant sign of the combined staining. Hamster liver substrate which is easily available might replace the expensive HEp-2 cells for detecting Scl-70 antibody.

Antibodies targeting extractable nuclear antigens: historical development and current knowledge

“…The antigen was termed Scl‐70 after the molecular weight of approximately 70 kDa of the protein detected in first experiments. During later experiments with inhibitors of proteolysis, additional protein antigens of 86, 89, 95 and 100–105 kDa were identified, which specifically reacted with the Scl‐70 antibody 72 …”

Fever of unknown origin secondary to type I crescentic glomerulonephritis and anti-SCl 70 antibodies without clinical manifestations of systemic sclerosis

“…Using a recombinant peptide as antigen has allowed better standardization with consistent results between different laboratories [16]. Specificity of anti-Scl 70 antibody for diffuse scleroderma is near to 98-100% [17][18][19][20]. Anti-Scl 70 antibodies are seldom seen in healthy people or patients without scleroderma.…”