• Incidence Testing
• Rapid Test Platform
• Oral Fluid Sampling System
• Molecular Diagnostics

ORAL FLUID SAMPLING SYSTEM

There has long been an attraction to oral fluid as a specimen for detection of various analytes because of the inexpensive, safe, and non-invasive methods for sample collection compared to blood testing. Ellison et al.¹ confirmed the presence of immunoglobulin in saliva in 1960. Two studies in the late 70’s reported the use of oral fluid collected with swabs for hepatitis B surface antigen and feline leukemia virus, respectively ^2,3. Throughout the next 30 years, increasing numbers of oral fluid testing studies were published. Today the testing of oral fluid for antibodies, antigens, and other analytes is a well-established and accepted form of clinical care, monitoring, and research throughout the world as evidenced by the numerous applications approved by US FDA, including those for HIV diagnosis, as well as a wide variety of publications in the scientific literature. These published studies support the efficacy of oral fluid testing in a number of diverse applications including detection of antibody to (1) infectious bacterial diseases (such as shigella dysentery ⁴, Haemophilus influenza ⁵, and Bordetella pertussis ⁶), and (2) viral infections (HIV ^7,8, hepatitis A, B, C, ^9,10,11 Epstein-Barr virus infections ¹¹, and rubella ¹²). Thieme et al. expanded upon these studies to conclude that simultaneous detection of seroconversion occurs in serum and oral fluid samples for diseases such as Hepatitis A9 and after vaccination to measles, mumps, and rubella¹³. Other studies demonstrated the applicably of oral fluid for the detection of viral antigen (HBsAg), ^9,10 drugs of abuse ^14,15, and for the therapeutic monitoring of drugs ¹⁶.

Saliva is a complex mixture of parotid, submandibular, and sublingual and minor salivary gland secretions mixed with mucin, bacteria, leukocytes, sloughed epithelial cells and gingival crevicular fluid ⁷. Gingival crevicular fluid, or oral mucosal transudate (OMT), is the fluid derived from the passive transport of serum components through the oral mucosa into the mouth. The concentrations of Immunoglobulin G (IgG) and other serum components in this fluid are significantly higher than in whole saliva ¹⁷. Consequently, collection of oral fluid from this area of the mouth was identified as the most promising source of fluid for diagnostic testing. The Aware Messenger™ device utilizes a clean untreated swab made of a soft absorbent material that targets those OMT-rich areas in the mouth when used as instructed. After a brief brushing along the gum lines, the oral fluid on the swab is briefly mixed with the proprietary Aware Messenger™ sample buffer containing preservatives, stabilizing agents, immunoassay-friendly detergents and other components. Finally, the swab is discarded, the tube is capped, and the sample is ready for transport and/or testing.

The Aware Messenger™ device, used in conjunction with traditional immunoassays (e.g. ELISA), adds the advantages of an oral fluid specimen, such as ease of collection and transport, to the benefits offered by conventional laboratory-based testing such as high throughput batch processing, automation, quantitative results, and lower costs.

Please note that although the Aware Messenger™ sample buffer has been formulated for compatibility with immunoassays, specific test protocols for any given assay must be optimized and the performance of the Aware Messenger™ specimen should be validated for each individual application by the laboratory performing the test. In stability studies conducted by Calypte, specific antibody was shown to be preserved for at least 3 weeks at up to 37°C. However, it is recommended that the stability of the specific antibody or analyte in question be assessed by a validated method.

In summary, the Aware Messenger™, device was designed to specifically accomplish four principle functions:

1. Collect and release human oral mucosal transudate, a component of oral fluid that is rich with representative entities of the blood (e.g. IgG, other serum proteins, etc.)
2. Stabilize the specimen to allow for testing at a later time at a site away from where the specimen was collected
3. Provide a matrix that is compatible for immunoassays
4. Allow for transport of the specimen to a laboratory for batch testing

¹Ellison, S.A., P.A. Mashimo, and I.D. Mandel. Immunochemical studies of human saliva. I. The demonstration of serum proteins in whole and parotid saliva. J. Dent. Res. 1960; 29: 892-899.
²Petersen NJ, et al. Hepatitis B Surface Antigen in Saliva, Impetiginous Lesions, and the Environment in Two Remote Alaskan Villages. Journal of Applied and Environmental Microbiology. 1976; 32:572-574.
³Francis D.P., M Essex, S M Cotter, D Gayzagian and D Hamm. A simple method for quantitating. salivary levels of virus using calcium alginate swabs. J. Clin. Pathol. 1979; 32:514-515
⁴Oberhelman, R.A., D.J. Kopecko, E. Salazar-Lindo, et.al. Prospective study of systemic and mucosal immune response in dysenteric patients to specific Shigella invasion plasmid antigens and lipopolysaccharides. Infect. Immun. 1991; 59:2341-2350.
⁵Gilsdorf, J.R., and W.M. McDonnell. Mucosal antibodies to Haemophilus influenzae type B capsular polysaccharide. Pediatric Research 1991; 29:420-423.
⁶Zackrisson, G., T. Lagergard, B. Troofors, and I. Krantz. Immunoglobulin A antibodies to pertussis toxin and filamentous hemagglutinin in saliva from patients with pertussis. J. Clin. Microbiol. 1990; 28:1502-1505.
⁷Granade T.C. et al. Detection of antibodies to human immunodeficiency virus type 1 in oral fluids: a large-scale evaluation of immunoassay performance. Clin Diagn Lab Immunol. 1998; 5(2):171-5.
⁸George J.R., J.H. Fitchen, A.S. Goldstein and M.S. Hindahl. Evaluation of a system using oral mucosal transudate for HIV-1 antibody screening and confirmatory testing. OraSure HIV Clinical Trials Group. JAMA. 1997 15;277(3):254-8. Erratum in: JAMA 1997; 12;227(10):792.
⁹Thieme, T., P. Yoshihara, S. Piacentini, & M. Beller. Clinical Evaluation of Oral Fluid Samples for Diagnosis of Viral Hepatitis. Journal of Clinical Microbiology. 1992; 30:1076-1079.
¹⁰Sherman, K.E., R.L. Creager, J. O’Brien, S. Sargent, S. Piacentini, & T. Thieme. The Use of Oral Fluid for Hepatitis C Antibody Screening. American Journal of Gastroenterology. 1994; 89:2025-2027.
¹¹Andersson, J., S. et al. Effect of acyclovir on infectious mononucleosis: A double-blind placebo-controlled study. J. Infectious Dis. 1986; 153:283-290.
¹²Friedman, M.G., M. Phillip, and R. Dagan. Virus-specific IgA in serum, saliva, and tears of children with measles. Clin. Exp. Immunol. 1989; 75:58-63.
¹³Thieme, T., S. Piacentini, S. Davidson, & K. Steingart. Determination of Measles, Mumps, and Rubella Immunization Status Using Oral Fluid Samples. Journal of the American Medical Association. 1994; 272:219-221.
¹⁴Davey J., N. Leal, and J. Freeman. Screening for drugs in oral fluid: illicit drug use and drug driving in a sample of Queensland motorists. Drug Alcohol Rev. 2007; 26(3):301-7.
¹⁵Cone EJ, Clarke J, Tsanaclis L. Prevalence and disposition of drugs of abuse and opioid treatment drugs in oral fluid. J Anal Toxicol. 2007; 31(8):424-33.
¹⁶Thieme, T., et al. (1993) Therapeutic drug monitoring using oral samples collected with the OraSure device. Ann N Y Acad Sci. 1993; 20:694:337-9.
¹⁷Mortimer, P.P, and J.V. Parry. Non-invasive virological diagnosis. Are saliva and urine specimens adequate substitutes for blood? Med. Virol. 1991; 1:73-78.