April 25, 2022

The Importance of Detecting Autoimmune Diseases During Preclinical and Clinical Stage

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Medically Reviewed by

Updated On

September 17, 2024

Autoimmunity is when the intricate and normally defensive immune system creates antibodies that work against the body’s cells and tissues instead of against harmful invaders. There are about 100 different autoimmune diseases that plague 5-9% of the adult world population.

Lab testing shows that an increasing number of Americans have positive antibody results that indicate autoimmunity. These autoantibodies can be detected in the blood years before the actual appearance of clinical symptoms. This is because autoimmune diseases progress through the stages of initiation (activation), propagation (symptom presentation), tissue damage, degeneration, and deformation.

The key to successful disease management and treatment is to detect autoimmune diseases at the initiation stage, not at the stage of degeneration and deformation when the patient may already be suffering pain and debilitation. This is possible using blood tests that measure antibodies against ANA, ENA, dsDNA, RF, actin, mitochondria, and immune complexes. This screening for the autoimmune disease at the subclinical stage provides a window of opportunity for early intervention by healthcare providers.

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Introduction

According to autoimmunologists, autoimmunity is the failure of the body to recognize its own tissue, which results in an immune response against its cells and tissue antigens. Any disease resulting from such an abnormal immune response is labeled an autoimmune disease.

Autoimmune diseases affect 5-9% of the world’s population and can be defined by the presence of pathogenic autoantibodies, autoreactive T-helper-1 and T-helper-17 cells, and their reaction against the host or self-tissue components (1). One way to look at it is to think of the immune cells as the body’s defensive army; while the commander, the regulatory T-cell (Treg) is sleeping on the job, the autoantibodies and autoreactive Th1 and Th17 cells (the soldiers) misbehave and start attacking their comrades. Another way is if the Treg is asleep in the backseat and unable to give directions, the autoantibody, Th1, and Th17 drive the car out of control, causing an autoimmunity accident to hit the host (see Figure 1).

When the Treg is sleeping on the job, the autoantibody, Th1 and Th17 cells drive the car out of control and cause an autoimmune accident to hit the host

In autoimmune diseases, it seems that pathogenic autoreactive antibodies or reactive T cells against defined self-antigens appear in the blood years before the development of the active disease. In fact, it has been shown that autoantibodies can be present in the blood from 3 months to 19 years before the development of different autoimmune diseases (2,3).

In a comprehensive review by Ma et al. that was published in the Journal of Autoimmunity 2017, it was shown that the etiology of autoimmune diseases is due to the combination of genetic predisposition and environmental factors that change the expression of our regulatory genes through different mechanisms including epigenetics (4). It also showed that autoantibodies had been detected in most autoimmune diseases before the appearance of clinical symptoms (4).

For example, it was demonstrated that antinuclear antibody (ANA) and ribonuclear protein/extractable nuclear antigens (ENA) appear in the blood of patients with lupus and Sjögren’s syndrome 7-8 years before the actual presentation of symptoms, while the presence of anti-mitochondrial M2 antibody in the blood precedes the clinical manifestation of primary biliary cirrhosis by 19 years (4). This is because autoimmune diseases develop through the stages of initiation, activation, propagation and symptom presentation, tissue damage, degeneration, or deformation (5), as shown in Figure 2.

Patients in the initiation phase, even with the presence of antibodies in the blood, are typically unaware of early clinical symptoms either because their health care provider does not order any specialized blood tests or they consider the standard CBC, chemistry, CRP, and other basic tests as sufficient, and thus screening for possible autoimmunity is not correctly done.

Diagnosing an autoimmune disease can be a monumentally time-consuming, exasperating task. This is because many of these disorders share similar symptoms, making it difficult for the health care practitioner to pinpoint the specific autoimmune condition. The initial symptoms of autoimmunity may include fatigue, aching tendons or muscles, inflammation, and low fever. Many patients are not diagnosed until these innocuous symptoms manifest into clinical components and sub-optimal health.

Furthermore, autoimmune disorders are significantly on the rise(6). About 52 million Americans suffer from autoimmune-related disorders.

In one study published in 2020 in the journal Arthritis & Rheumatology by the National Institute of Environmental Health (7), Dr. F. Miller and his group reported that while in the 1970s, only 4% (8 million) of the population were ANA positive, ANA positivity between 1988-1991 increased to 11% (22 million), and from 2011-2012 rose to 15.9% or 41 million (see Figure 3).

Frequencies of antinuclear antibodies among the US population over the years

These scientists suggested that because people have not changed genetically in the past 50 years, factors related to the environment and lifestyle could be involved in the increase of ANA in the population.

This role of environmental triggers was addressed in three different manuscripts, one published in 2015 in the Journal of Autoimmunity (5), and the additional two in the Journal of Pathophysiology in 2021 and 2022 by this author (8, 9).

Overall the data suggests that currently, at least 41 million Americans are in the process of developing some kind of autoimmune disease without having any clinical symptoms. Thus, early detection of autoimmune diseases at a subclinical stage is vital because it provides a window of opportunity for intervention.

Diagnosis of Autoimmune Diseases

The diagnosis of autoimmune disorders is based on clinical symptomatology and serological assays such as ANA, ENA, rheumatoid factor (RF), and immune complexes.

The detection of other autoantibodies can be employed for more specific determination of autoimmune diseases, such as double-stranded DNA antibody elevation in lupus erythematosus and citrullinated peptide antibody in rheumatoid arthritis, and actin and mitochondrial antibody in autoimmune liver disease.

Furthermore, autoantibodies can determine the progress of the disease and whether or not therapy implementation has been effective.

Biomarkers Used in Preclinical and Clinical Diagnosis of Autoimmune Diseases

ANA (Antinuclear Antibodies)

ANA are antibodies that attack normal proteins in the nucleus of the body cell. Overall abnormal levels of ANA are served as a screening for many autoimmune diseases (10).

High levels of ANA are detected in patients with rheumatoid arthritis, scleroderma, lupus, vasculitis, Sjögren’s syndrome, and mixed connective tissue disease (MCTD).

ENA (Extractable Nuclear Antigen)

These antibodies attack normal proteins called ribonucleoproteins or proteins that do not contain DNA (11, 12).

Because ANA is found in a wider variety of connective tissue diseases, it cannot detect specific diseases, but it is used as a sensitive screening assay. In comparison, elevated ENA can contribute significantly to the diagnosis and prognosis of patients suspected of a variety of connective tissue diseases such as scleroderma, polymyositis, Sjögren’s syndrome, and systemic lupus erythematosus (SLE).

Overall positive ENA indicates a reaction with SSA, SS-B, Sm, RNP, SCL-70, ad Jo-1 antigens which requires specific testing. Autoantibodies against ENA occur in a large number of patients with system rheumatic diseases (11, 12).

dsDNA (Double Stranded Deoxyribonucleic Acid)

Autoantibodies to single-stranded and double-stranded DNA are detected in different autoimmune disorders (13, 14). While these antibodies are not disease-specific, single-stranded DNA antibodies are detected in the blood of patients with a range of autoimmune disorders that include SLE, drug-induced lupus, MCTD, RA, scleroderma, and Sjögren’s syndrome. But anti-dsDNA is more specifically detected in the blood of patients with SLE, where immune complex formation between antigen and antibody, along with the involvement of complement, together play a role in the induction of inflammation and damage to the renal and vascular tissues.

RF (Rheumatoid Factor)

This IgM antibody is produced by the immune system and works against our IgG when it aggregates (14, 15).

Factors that aggregate IgG:

IgG drug conjugate
IgG bacterial antigen conjugate
IgG lectin conjugate

RF is the most consistent serological marker found in about 70-80% of patients with RA. Elevated RF is detected in the blood of patients with parasitic diseases, liver disease, sarcoidosis, and SLE. An increase in the level of RF may accompany a variety of acute immune responses, particularly infections with different viruses, including Epstein Barr Virus (EBV) (16).

Anti-Actin or Smooth Muscle Antibody

Actin is a major component of smooth muscle (17). Antibodies are usually directed against the actin component of the cytoskeleton. Usually, low amounts of these antibodies are detected in 3-18% of sera obtained from the general population. However, anti-actin antibodies are found in 52-85% of patients with autoimmune hepatitis (AIH) or chronic active hepatitis (CAH) and 22% of patients with primary biliary cirrhosis (PBC).

Mitochondrial Antibodies

The mitochondrial (M2) antigen is part of the pyruvate dehydrogenase (PDH) complex of tightly organized polypeptides and cofactors that work together in concert. The enzyme converts pyruvate into acetyl-coenzyme A in the citric acid cycle, which is important in cellular respiration inside the mitochondria. Anti-mitochondrial antibodies (AMA) are detected in patients with PBC.

Since the presence of AMA can precede the development of symptomatic disease, the ability to identify the presence of markers for PBC can contribute to earlier diagnosis and treatment and may help to slow the progression of the disease.

Note: Chemical xenobiotics used in cosmetics and food additives were discovered to share homology with PDH and mitochondrial antigen. Thus mitochondrial antibodies may also be detected in the blood due to a reaction to these xenobiotics (18-21).

Circulating Immune Complexes (CIC)

Circulating immune complexes that bind C1q complement are present in human serum in small quantities that are removed by the Kupffer cells of the liver. However, in the presence of overwhelming amounts of antigens and antibodies, antigen-antibody interactions and abnormal liver function can result in the formation of immune complexes (22).

If these complexes are deposited in vascular structures, the result can be a complex immune disease accompanied by tissue damage.

High levels of C1q binding immune complexes are detected in patients with an active humoral immune response to infectious agents and other environmental factors. Very significant elevations of immune complexes were reported in cancer patients, and their levels correlated with the stage of the disease.

Immune complexes can be deposited in the joints and kidneys, contributing to inflammation and autoimmune diseases such as rheumatoid arthritis, lupus, and nephropathy (23, 24).

The Importance of Identifying Early Autoimmune Events

Dissecting the immunologic response specific to inciting agents is critical for identifying the early events necessary for the induction of autoimmunity and other diseases. We believe that elucidation of the exposome-induced antibody response will provide insights into the early events necessary for creating and expanding autoreactive T and B cells, a cardinal feature of the autoimmune response.

Summary

Identifying early events in the course of disease development is the core principle of functional medicine and personalized lifestyle medicine.

In this article, we have mentioned that environmental factors play a role in inducing autoimmunity, and we have only touched on infections, one of the commonest of these environmental triggers. Examples of infections that play a crucial role in autoimmunity include viruses such as EBV, CMV, HSV-1, HSV-2, HHV-6, VZV, measles, SARS-CoV-2, and Lyme disease and its co-infections.

More information about these infections, their involvement with the silent epidemic of autoimmunity, and the importance of the reliable and accurate measurement of their biomarkers will be discussed in additional articles.

Articles That May Interest You

A Functional Medicine Approach to Autoimmune Disease

Podcast

Autoimmune Diseases with Dr. Rob Silverman

Autoimmunity occurs when the immune system, which usually protects the body, mistakenly targets the body's own cells and tissues. There are about 100 different autoimmune conditions that affect 5-9% of the adult world population.

Lab testing shows that an increasing number of Americans have positive antibody results that may suggest autoimmunity. These autoantibodies can sometimes be detected in the blood years before the actual appearance of clinical symptoms. This is because autoimmune conditions may progress through stages such as initiation (activation), propagation (symptom presentation), tissue damage, degeneration, and deformation.

Detecting autoimmune conditions at the initiation stage, rather than at the stage of degeneration and deformation, may help in managing the condition more effectively. Blood tests that measure antibodies against ANA, ENA, dsDNA, RF, actin, mitochondria, and immune complexes can be used for screening. This screening at the subclinical stage provides a window of opportunity for healthcare providers to consider early intervention.

[signup]

Introduction

According to experts, autoimmunity is when the body fails to recognize its own tissue, leading to an immune response against its cells and tissue antigens. Any condition resulting from such an abnormal immune response is labeled an autoimmune condition.

Autoimmune conditions affect 5-9% of the world’s population and can be identified by the presence of certain autoantibodies and autoreactive cells. One way to understand this is to think of the immune cells as the body’s defensive army; if the regulatory T-cell (Treg) is not functioning properly, the autoantibodies and autoreactive cells may start attacking the body's own tissues.

When the Treg is not functioning properly, the autoantibody, Th1 and Th17 cells may cause an autoimmune response

In autoimmune conditions, it seems that certain autoantibodies or reactive T cells against defined self-antigens can appear in the blood years before the development of active symptoms. Studies show that autoantibodies can be present in the blood from 3 months to 19 years before the development of different autoimmune conditions.

A comprehensive review by Ma et al. published in the Journal of Autoimmunity in 2017 suggested that the causes of autoimmune conditions may include a combination of genetic predisposition and environmental factors that influence gene expression through mechanisms like epigenetics. It also showed that autoantibodies had been detected in most autoimmune conditions before the appearance of clinical symptoms.

For example, it was demonstrated that antinuclear antibody (ANA) and ribonuclear protein/extractable nuclear antigens (ENA) may appear in the blood of individuals with lupus and Sjögren’s syndrome 7-8 years before symptoms, while the presence of anti-mitochondrial M2 antibody in the blood may precede the clinical manifestation of primary biliary cirrhosis by 19 years. This is because autoimmune conditions may develop through stages such as initiation, activation, propagation and symptom presentation, tissue damage, degeneration, or deformation.

Individuals in the initiation phase, even with the presence of antibodies in the blood, may not be aware of early clinical symptoms either because their healthcare provider does not order any specialized blood tests or they consider standard tests as sufficient, and thus screening for possible autoimmunity may not be done correctly.

Diagnosing an autoimmune condition can be a time-consuming and challenging task. This is because many of these conditions share similar symptoms, making it difficult for healthcare practitioners to identify the specific autoimmune condition. Initial symptoms may include fatigue, aching tendons or muscles, inflammation, and low fever. Many individuals are not diagnosed until these symptoms become more pronounced.

Furthermore, autoimmune conditions are reportedly on the rise. About 52 million Americans are affected by autoimmune-related conditions.

In a study published in 2020 in the journal Arthritis & Rheumatology by the National Institute of Environmental Health, Dr. F. Miller and his group reported that while in the 1970s, only 4% (8 million) of the population were ANA positive, ANA positivity between 1988-1991 increased to 11% (22 million), and from 2011-2012 rose to 15.9% or 41 million.

This role of environmental triggers was addressed in three different manuscripts, one published in 2015 in the Journal of Autoimmunity, and the additional two in the Journal of Pathophysiology in 2021 and 2022 by this author.

Overall, the data suggests that currently, at least 41 million Americans may be in the process of developing some kind of autoimmune condition without having any clinical symptoms. Thus, early detection of autoimmune conditions at a subclinical stage is important because it provides a window of opportunity for intervention.

Diagnosis of Autoimmune Conditions

The diagnosis of autoimmune conditions is based on clinical symptoms and serological assays such as ANA, ENA, rheumatoid factor (RF), and immune complexes.

The detection of other autoantibodies can be employed for more specific determination of autoimmune conditions, such as double-stranded DNA antibody elevation in lupus erythematosus and citrullinated peptide antibody in rheumatoid arthritis, and actin and mitochondrial antibody in autoimmune liver disease.

Furthermore, autoantibodies can help determine the progress of the condition and whether or not therapy implementation has been effective.

Biomarkers Used in Preclinical and Clinical Diagnosis of Autoimmune Conditions

ANA (Antinuclear Antibodies)

ANA are antibodies that may target normal proteins in the nucleus of the body cell. Abnormal levels of ANA are used as a screening for many autoimmune conditions.

High levels of ANA are detected in individuals with rheumatoid arthritis, scleroderma, lupus, vasculitis, Sjögren’s syndrome, and mixed connective tissue disease (MCTD).

ENA (Extractable Nuclear Antigen)

These antibodies may target normal proteins called ribonucleoproteins or proteins that do not contain DNA.

Because ANA is found in a wider variety of connective tissue conditions, it cannot detect specific conditions, but it is used as a sensitive screening assay. In comparison, elevated ENA can contribute significantly to the diagnosis and prognosis of individuals suspected of a variety of connective tissue conditions such as scleroderma, polymyositis, Sjögren’s syndrome, and systemic lupus erythematosus (SLE).

Overall positive ENA indicates a reaction with SSA, SS-B, Sm, RNP, SCL-70, and Jo-1 antigens which requires specific testing. Autoantibodies against ENA occur in a large number of individuals with systemic rheumatic conditions.

dsDNA (Double Stranded Deoxyribonucleic Acid)

Autoantibodies to single-stranded and double-stranded DNA are detected in different autoimmune conditions. While these antibodies are not disease-specific, single-stranded DNA antibodies are detected in the blood of individuals with a range of autoimmune conditions that include SLE, drug-induced lupus, MCTD, RA, scleroderma, and Sjögren’s syndrome. But anti-dsDNA is more specifically detected in the blood of individuals with SLE, where immune complex formation between antigen and antibody, along with the involvement of complement, together may play a role in the induction of inflammation and damage to the renal and vascular tissues.

RF (Rheumatoid Factor)

This IgM antibody is produced by the immune system and may work against our IgG when it aggregates.

Factors that aggregate IgG:

IgG drug conjugate
IgG bacterial antigen conjugate
IgG lectin conjugate

RF is the most consistent serological marker found in about 70-80% of individuals with RA. Elevated RF is detected in the blood of individuals with parasitic conditions, liver conditions, sarcoidosis, and SLE. An increase in the level of RF may accompany a variety of acute immune responses, particularly infections with different viruses, including Epstein Barr Virus (EBV).

Anti-Actin or Smooth Muscle Antibody

Actin is a major component of smooth muscle. Antibodies are usually directed against the actin component of the cytoskeleton. Usually, low amounts of these antibodies are detected in 3-18% of sera obtained from the general population. However, anti-actin antibodies are found in 52-85% of individuals with autoimmune hepatitis (AIH) or chronic active hepatitis (CAH) and 22% of individuals with primary biliary cirrhosis (PBC).

Mitochondrial Antibodies

Since the presence of AMA can precede the development of symptomatic conditions, the ability to identify the presence of markers for PBC can contribute to earlier diagnosis and management and may help to slow the progression of the condition.

Circulating Immune Complexes (CIC)

If these complexes are deposited in vascular structures, the result can be a complex immune condition accompanied by tissue damage.

High levels of C1q binding immune complexes are detected in individuals with an active humoral immune response to infectious agents and other environmental factors. Very significant elevations of immune complexes were reported in cancer patients, and their levels correlated with the stage of the condition.

Immune complexes can be deposited in the joints and kidneys, contributing to inflammation and autoimmune conditions such as rheumatoid arthritis, lupus, and nephropathy.

The Importance of Identifying Early Autoimmune Events

Understanding the immunologic response specific to inciting agents is important for identifying the early events necessary for the development of autoimmunity and other conditions. It is believed that understanding the exposome-induced antibody response will provide insights into the early events necessary for creating and expanding autoreactive T and B cells, a key feature of the autoimmune response.

Summary

Identifying early events in the course of condition development is a core principle of functional medicine and personalized lifestyle medicine.

In this article, we have mentioned that environmental factors may play a role in inducing autoimmunity, and we have only touched on infections, one of the commonest of these environmental triggers. Examples of infections that may play a role in autoimmunity include viruses such as EBV, CMV, HSV-1, HSV-2, HHV-6, VZV, measles, SARS-CoV-2, and Lyme disease and its co-infections.

Articles That May Interest You

A Functional Medicine Approach to Autoimmune Disease

Podcast

Autoimmune Diseases with Dr. Rob Silverman

The information provided is not intended to be a substitute for professional medical advice. Always consult with your doctor or other qualified healthcare provider before taking any dietary supplement or making any changes to your diet or exercise routine.

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Lab Tests in This Article

ANA Screen by Access Med Labs

Serum

The ANA Screen detects the presence of clinically relevant circulating autoantibodies in serum.

Rheumatoid Factor by Access Med Labs

Serum

This is a single-marker test measuring rheumatoid factor. It is used for the diagnosis of rheumatoid arthritis and in monitoring the therapeutic response to the disease.

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