Download J Immunol Methods

Pediatrics. 2006 Dec;118(6):2498-503.
A fast procedure for the detection of defects in Toll-like receptor signaling.
von Bernuth H, Ku CL, Rodriguez-Gallego C, Zhang S, Garty BZ, Marodi L, Chapel
H, Chrabieh M, Miller RL, Picard C, Puel A, Casanova JL.
Laboratory of Human Genetics of Infectious Diseases, University of Paris Rene
Descartes, Institut National de la Sante et de la Recherche Medicale U550,
Necker Medical School, Paris, France. [email protected]
OBJECTIVES: Inborn defects in Toll-like receptor signaling are recently
described primary immunodeficiencies that predispose affected children to
life-threatening infections. Patients with interleukin-1 receptor-associated
kinase-4 deficiency are prone to invasive pneumococcal disease, and patients
with UNC-93B deficiency are prone to herpes simplex virus encephalitis. These
genetic disorders are underdiagnosed, partly because diagnosis currently
requires expensive and time-consuming techniques available at only a few
specialized centers worldwide. We, therefore, aimed to develop a cheap and fast
test for the detection of defects in Toll-like receptor signaling. PATIENTS AND
METHODS: We used flow cytometry to evaluate the cleavage of membrane-bound
L-selectin on granulocytes in 38 healthy controls and in 7 patients with
genetically defined Toll-like receptor signaling defects (5 patients with
interleukin-1 receptor-associated kinase-4 deficiency and 2 patients with
UNC-93B deficiency), on activation with various Toll-like receptor agonists.
RESULTS: Impaired L-selectin shedding was observed with granulocytes from all of
the interleukin-1 receptor-associated kinase-4-deficient patients on activation
with agonists of Toll-like receptors 1/2, 2/6, 4, 7, and 8 and with granulocytes
from all of the UNC-93B-deficient patients on activation with agonists of
Toll-like receptors 7 and 8. All of the healthy controls responded to these
stimuli. CONCLUSIONS: The assessment of membrane-bound L-selectin cleavage on
granulocytes by flow cytometry may prove useful for the detection of primary
immunodeficiencies in the Toll-like receptor pathway, such as interleukin-1
receptor-associated kinase-4 deficiency and UNC-93B deficiency. This procedure
is cheap and rapid. It may, therefore, be suitable for routine testing worldwide
in children with invasive pneumococcal disease and in patients with herpes
simplex encephalitis.
PMID: 17142536 [PubMed - indexed for MEDLINE]