The Salimetrics Research Library
Look up current saliva research on
SIgA
and related analytes here!
Secretory Immunoglobulin A
Secretory Immunoglobulin A (SIgA) is a subclass of Immunoglobulin A (IgA), an antibody that plays a critical role in mucosal immunity. SIgA is the main immunoglobulin found in mucous secretions from the tear glands, salivary glands, mammary glands, the respiratory system, the genito-urinary tract, and the gastrointestinal tract. (1) SIgA is not synthesized by mucosal epithelial cells in these structures or derived from blood. Instead, it is produced by B-lymphocytes adjacent to the mucosal cells, then transported through the cell interiors, and released into the secretions from the cells. (2) SIgA plays a key role in protecting vulnerable areas such as the oral cavity, lungs, and gut from invading pathogens. (1) Differences in SIgA levels in the saliva from different glands have been observed in humans, with the highest levels found in the minor saliva glands. (2,3) SIgA exhibits a diurnal rhythm, decreasing from the highest levels in the morning to the lowest in the evening. (4) More »
Levels of SIgA in saliva vary in response to physical and psychological stress through interactions with the autonomic nervous system. (5,6) SIgA levels in saliva are affected by flow rates, with concentrations normally decreasing as flow rates increase. Measurement of flow rates is advisable in order to express SIgA secretion as a function of time. (6)
References
- Holmgren, J., Czerkinsky, C. (2005). Mucosal immunity and vaccines. Nature Medicine, 11(4 Suppl), s45-53.
- Brandtzaeg, P. (2007). Do salivary antibodies reliably reflect both mucosal and systemic immunity? Ann N Y Acad Sci, 1098, 288-311.
- Crawford, J.M., Taubman, M.A., Smith D.J. (1975). Minor salivary glands as a major source of secretory immunoglobulin A in the human oral cavity. Science, 190(4220), 1206-9.
- Li, T.-L., Gleeson, M. (2004). The effect of single and repeated bouts of prolonged cycling and circadian variation on saliva flow rate, immunoglobulin A and alpha-amylase responses. J Sports Sci, 22(11-12), 1015-1024.
- Tsujita, S., Morimoto, K. (1999). Secretory IgA in saliva can be a useful stress marker. Env Health Prev Med, 4, 1-8.
- Bishop, N.C., Gleeson, M. (2009). Acute and chronic effects of exercise on markers of mucosal immunity. Front Biosci, 1(14), 4444-56.
SIgA is Location Dependent
SIgA is Flow Rate Dependent (μg/mL)
Passive Drool is a Preferred Collection Method
SIgA Overview
| Approved Salivary Collection Devices | Serum-Saliva Correlation | Sensitivity | Sample Test Volume | Recommended Collection Volume | Special Considerations | Related Analytes |
|---|---|---|---|---|---|---|
| No | 2.5 μg/mL | 25 μL | 50 μL* | Yes |
*In addition to the volume recommended for each analyte, we recommend collecting an additional 300 μL to allow for liquid handling loss and possible repeat tests (500 µl recommended for TNF-α and IL-1β).
Salimetrics Products and Services for SIgA
| Testing Service | DNA Panel Available | Research Assay Kit | IVD Assay Kit | CE Marked Kit | Collection Supplies | Technical Support |
|---|---|---|---|---|---|---|
| Yes | Yes | Yes Specifications» |
No | No | Yes | Yes |
Salivary SIgA Kit Specifications
| Target Analyte: | SIgA |
| Catalog number: | 1-1602 (5PK 1-1602-5) |
| Testing protocol: | Download PDF |
| Format: | 96-well plate |
| Type: | Quantitation |
| Method: | EIA |
| Calibrator range: | 2.50 µg/mL – 600 µg/mL |
| Sensitivity: | 2.5 µg/mL |
| Saliva volume/test: | 25 µL |
| Incubation time: | 3.75 hours |
| Tests per kit: | 76 (singlet) |
| Correlation with serum: | N/A |
| Correlation with assays: | 0.91 compared to ELISA, 0.94 compared to RID assay |
| Controls included in kit? | Yes |
| MSDS sheets: | Available upon request |
