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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Jo-1 Ab

Test Code(s): JO1 / XJO1

CPT Code(s): 86235

Methodology: Enzyme Immunoassay

Clinical Significance: The Jo-1 antibodies test is an aid in the diagnosis of polymyositis and is not definitive in isolation. Antibodies to the Jo-1 antigen, also recognized as the enzyme histidyl-t RNA synthetase, are found in approximately 25% of patients with polymyositis. High proportions of patients with interstitial lung disease, associated with polymyositis, are positive for the antibody.

Days Performed: Mon-Fri, dayshift - day varies.

Turnaround Time: Stat: Not available stat.
Routine: 5 working days.

Specimen Requirements

Specimen: Blood

Collection Container: Preferred: Red top
Also Acceptable: Red cap with yellow ring (SST)

Collection Volume: Preferred: 3 mL
Pediatrics: 1 mL

Sample Analyzed: Serum

Volume Required: Preferred: 1 mL
Pediatrics: 0.3 mL

Specimen Processing: Centrifuge. Transfer cell-free serum to clear plastic vial. Refrigerate.

Specimen Transport: Transport specimen to UWHC Core Laboratory (B4/220). Transport with coolant pack if coming from UWHC Satellite lab location.

Unacceptable Criteria: Grossly hemolyzed, lipemic or turbid specimens should be avoided.

Stability: Ambient: 8 hours
Refrigerated: 1 week
Frozen: At -20 C or colder, no limit. Note: Avoid repeat freeze and thaw.


Normal Jo-1 Ab (0 days and up): Negative

Histidyl-t RNA synthetase antibodies, nti-Jo-1 antibodies

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