Red top tube or SST
Allow sample to clot at room temperature for 20 to 60 minutes. Centrifuge ASAP to separate serum from cells and aliquot cell-free serum into a labeled polypropylene or similar plastic tube.
Clotted or hemolyzed samples, plasma
Send serum Priority Overnight via FedEx and in a well insulated container with an ice pack or frozen on dry ice.
2-8°C for 48 hours, >1 month at -70°C
ELISA followed by confirmation by flow cytometry.
Immunology Lab - Functional Assay
PAP, pulmonary alveolar proteinosis, intracellular infection, GMCSFA
Granulocyte-macrophage colony-stimulating factor (GM-CSF) promotes the proliferation and differentiation of hematopoetic cells including macrophages, neutrophils and dendritic cells. Neutralization of GM-CSF activity can therefore impair the development and/or function of these cell types.
Neutralizing anti-GM-CSF autoantibodies are associated with pulmonary alveolar proteinosis (PAP), a rare lung disease that is characterized by the inability of macrophages to clear surfactant from the alveolar lung spaces. Additionally, anti-GM-CSF autoantibodies have been noted in patients with opportunistic infections with intracellular organisms such as M. avium complex, Cryptococcus, Nocardia and Aspergillus species. It is possible that neutralization of GM-CSF in vivo leads to compromised macrophage function which is a key component of the immune response to intracellular organisms.
Anti-GM-CSF autoantibodies are detected by an initial screening ELISA. If the result is positive, the test reflexes to a flow cytometry assay to determine the ability of the autoantibody to neutralize GM-CSF. Low titer, non-neutralizing autoantibodies may be detected in healthy individuals. Clinically significant anti-GM-CSF autoantibodies are reported when both the ELISA and the abilty to neutralize GM-CSF are positive.
Kitamura, T., et al. Idiopathic pulmonary alveolar proteinosis as an autoimmune disease with neutralizing antibody against granulocyte/macrophage colony-stimulating factor. The Journal of experimental medicine. 1999; 190:875-880.
Bonfield, T. L., et al. Anti-GM-CSF titer predicts response to GM-CSF therapy in pulmonary alveolar proteinosis. Clinical Immunology. 2002; 105:342-350.
Rosen, L. B., et al. Anti-GM-CSF autoantibodies in patients with cryptococcal meningitis. Journal of Immunology. 2013; 190:3959-3966
86353,88184,88185- Flow reflex