Immunoglobulin A (IgA), Serum/Plasma

Immunoglobulin A (IgA) is an antibody that plays a critical role in mucosal immunity. Its secretory form is the main immunoglobulin found in mucous secretions, including tears, saliva, colostrum, intestinal juice, vaginal fluid and secretions from the prostate and respiratory epithelium. It is also found in small amounts in blood. Because it is resistant to degradation by enzymes, secretory IgA can survive in harsh environments such as the digestive and respiratory tracts, to provide protection against microbes that multiply in body secretions. IgA is a poor activator of the complement system, and opsonises only weakly. Its heavy chains are of the type α.

Selective IgA deficiency (SIgAD) is a primary immunodeficiency disease and is the most common of the primary antibody deficiencies. Total IgA deficiency (IgAD) is defined as an undetectable serum IgA. IgAD is a complex disorder and several lines of evidence support a common pathogenesis for IgAD and common variable immunodeficiency (CVID). Raised levels are found in multiple myeloma and chronic inflammatory disorders.

1 ml Serum 1 ml Li-Heparin or K2-EDTA Plasma Stability: 8 Months at 15-25 °C 8 Months at 2-8 °C 8 Months at (-15)-(-25) °C

< 1 Year: 0 - 83 mg/dL 0.00 - 0.83 g/L 1-3 Years: 20 - 100 mg/dL 0.20 - 1.00 g/L 4-6 Years: 27 - 195 mg/dL 0.27 - 1.95 g/L 7-9 Years: 34 - 305 mg/dL 0.34 - 3.05 g/L 10-11 Years: 53 - 204 mg/dL 0.53 - 2.04 g/L 12-13 Years: 58 - 358 mg/dL 0.58 - 3.58 g/L 14-15 Years: 47 - 249 mg/dL 0.47 - 2.49 g/L 16-19 Years: 61 - 348 mg/dL 0.61 - 3.48 g/L > 19 Years: 70 - 400 mg/dL 0.70 - 4.00 g/L