A large protein used by the immune system to identify and neutralize antigens such as those that exist on bacteria and virus cells, including those that cause disease.
Each individual antibody recognizes one or more specific antigens, and antigens (a portmanteau of "antibody generator") of virtually any size and chemical composition can be recognized.
Diagnostic Biomarkers
SS-A (Ro) Antibodies
SSA
A type of anti-nuclear autoantibodies that are associated with many autoimmune diseases.
SS-B (La) Antibodies
SSB
While anti-SS-A/Ro antibodies are present in many autoimmune diseases, anti-SS-B/La antibodies are more specific to Sjögren's.
The absence of SS-A/Ro and SS-B/La autoantibodies does not exclude Sjögren's as a cause.
Complement C3
Complement component 3, often called C3, is an essential protein of the immune system.
The complement C3 blood test measures the activity of this protein in your blood.
Complement C4
Complement component 4, often called C4, is an essential protein of the immune system.
The complement C4 blood test measures the activity of this protein in your blood.
Salivary Gland Protein 1
SP-1
Looks for IgG antibodies in salivary proteins.
Carbonic Anhydrase 6
CA6
Measures antibodies to an enzyme in the saliva.
Parotid Secretory Protein
PSP
Looks for IgG antibodies in salivary proteins.
Antinuclear Antibodies using Immunofluorescence
ANA using IFA
ANA testing is commonly used in the evaluation of systemic autoimmune rheumatic diseases.
A positive ANA result can also be seen in various other diseases and even in healthy individuals.
Rheumatoid Factor
RF
High blood serum levels may be indicative of an autoimmune disease.
Rheumatoid factor is an autoantibody produced by the immune system that attacks your own cells.
hs-CRP
C-reactive protein (CRP) is produced by the liver. Its level rises when there's inflammation in your body.
Measures the level of C-reactive protein in your blood.
IgA
IgA is a binding molecule that neutralizes toxins without eliciting an inflammatory immune response.
Secretory IgA is a neutralizing antibody that is found in all of your secretory fluids (tears, saliva, semen, ...) that doesn't illicit an immune response.
It can bind to and neutralize viruses, bacteria, bacterial toxins, environmental toxins, environmental particles to render those toxins ineffective without stimulating your immune system.