Assist in diagnosis of innate immunodeficiencies when genetic defects of the innate immune system are suspected in individuals negative for other immunodeficiencies (eg, no detectable abnormality of antibody function, complement activity, neutrophil function, or cell-mediated immunity).
- Patient Preparation
- Collect control specimen from a healthy individual unrelated to patient at approximately the same time as and under similar conditions to the patient.
- Green (sodium heparin) (patient) AND green (sodium heparin) (control). Also acceptable: Yellow (ACD solution A) (patient) AND yellow (ACD solution A) (control). Patient and control specimens must be collected within 48 hours of test performance.
- Specimen Preparation
- Transport 10 mL whole blood (patient) AND 10 mL whole blood (control) in original collection tubes. (Min: 7 mL (patient) AND 7 mL (control)) Do not refrigerate or freeze. LIVE CELLS REQUIRED.
Infant Minimum: 3 mL whole blood (patient) AND 7 mL whole blood (control).
- Storage/Transport Temperature
- CRITICAL ROOM TEMPERATURE.
- Unacceptable Conditions
- Yellow (ACD Solution B). Refrigerated or frozen specimens.
- Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable
New York State Clients: Ambient 24 hours; Refrigerated: Unacceptable; Frozen: Unacceptable
TLR-specific ligands include Pam3CSK4, a synthetic bacterial lipoprotein (TLR2-TLR1 ligand); zymosan cell wall particles from Saccharomyces cerevisiae (TLR6-TLR2 ligand); poly (I:C), a synthetic analog of dsRNA (TLR3 ligand); lipopolysaccharide (LPS) ultra-pure S. minnesota LPS (TLR4 ligand); flagellin purified from S. typhimurium (TLR5 ligand); and CL097 imidazoquinoline compound (TLR7-TLR8 ligand).
Limitation: Defects in TLR3 associated with Herpes Simplex Encephalitis may not be detected in this assay based on the reported instance of a patient with compound heterozygous mutations in TLR3 leading to decreased cytokine production in response to Poly I:C in fibroblasts but not PBMCs1.
Proteins IRAK-4 and MyD88 play essential roles in TLR-mediated signaling. Defects in IRAK-4 and MyD88 result in compromised TLR signaling. Exceptions are , TLR3 and endosomal TLR4, which, are IRAK-4 and MyD88 independent.
1. Guo Y, Audry M, Ciancanelli M, Alsina L, Azevedo J, Herman M, et al. Herpes simplex virus encephalitis in a patient with complete TLR3 deficiency: TLR3 is otherwise redundant in protective immunity. J Exp Med. 2011;208(10):2083-98.
|Component Test Code*||Component Chart Name||LOINC|
|0051589||Toll-Like Receptor Function|
- TLR Function