IVD of Autoimmune

What is autoimmune?

Autoimmune is when the immune system of the body accidentally attacks its own tissues as foreign invaders. It is a self-attack that can happen anywhere in the body, depending on the autoimmune condition at hand.

What are the symptoms of autoimmune diseases?

Typical autoimmune diseases symptoms vary widely by disease.

  • Tiredness: A persistent sense of sluggishness or weakness that doesn't diminish with sleep.
  • Joint Pain and Swelling: In conditions such as rheumatoid arthritis, the joints may become warm, swollen, and painful.
  • Skin Issues: Itches (lupus's butterfly rash, for example) or other skin abnormalities.
  • Abdominal pain or Digestive issues: Examples: Crohn's disease or celiac disease.
  • Chronic Fever: Inexplicable, long-lasting fever.
  • Edema and Irritation: Pain that can be experienced in any part of the body.
  • Neurological: Feelings of numbness, tingling, or vision problems (as in multiple sclerosis).
  • Hair Loss: Hair is shed from one area to another, including alopecia areata.
  • Splendid Glands: Spilled lymph nodes.
  • Struggling to Concentrate: Also known as "brain fog," where someone can't focus on anything.

Symptoms vary for every autoimmune disease, but some of them are shared across many different autoimmune diseases.

Biomarkers of Autoimmune Diseases:

Autoantibodies:

Antinuclear antibodies (ANA): Commonly found in systemic lupus erythematosus (SLE) and other connective tissue disorders.

Rheumatoid factor (RF): Relative to rheumatoid arthritis (RA).

Anti-cyclic citrullinated peptide (anti-CCP) antibodies: More effective against RA.

Anti-dsDNA (anti-double-stranded DNA) antibodies: Unique to SLE.

Anti-Smith antibodies: Specific for SLE.

Anti-Jo-1 antibodies: Commonly known as polymyositis and dermatomyositis.

Anti-neutrophil cytoplasmic antibodies (ANCA): Contributes to vasculitis.

Cytokines and Chemokines:

Increased levels of some cytokines (TNF-alpha, IL-1, IL-6) can be a sign of inflammation in autoimmune conditions.

Acute Phase Proteins:

C-reactive protein (CRP) and Erythrocyte sedimentation rate (ESR): Broad-based indicators of inflammation.

Genetic Markers:

A few HLA (human leukocyte antigen) haplotypes carry a higher risk of autoimmune disease.

Diagnostic Methods for Autoimmune Diseases

To identify autoantibodies and assess inflammatory markers such as CRP and ESR. A complete blood count (CBC) for any anemia or other abnormalities in the blood.

Imaging Studies

X-rays, MRI, and CT scans: To detect damage to joints, inflammation of organs, or other structural changes.

Biopsy: A tissue biopsy can be used to detect inflammation or damage.

Functional Tests:

Lung function tests for autoimmune lung diseases.

Peripheral neuropathology: nerve conduction experiments.

Clinical Evaluation:

Diagnosis demands thorough physical examination and medical history.

Specialized Tests:

Depending on the illness suspected, tests such as endoscopy could be performed for diseases such as celiac disease.

Case Study

Case 1: Ohkura N, Sakaguchi S. Transcriptional and epigenetic basis of Treg cell development and function: its genetic anomalies or variations in autoimmune diseases. Cell Res. 2020 Jun;30(6):465-474. doi: 10.1038/s41422-020-0324-7. Epub 2020 May 4. PMID: 32367041; PMCID: PMC7264322.

Anomalies in the formation of Treg-specific epigenome, in particular, Treg-specific super-enhancers, which largely include Treg-specific DNA demethylated regions, are indeed able to cause autoimmune diseases in rodents.

Fig2. Expression of Treg-associated genes along Treg differentiation in the thymus. a Schematic representation of the developmental paths of Treg cells. DN: double negative T cells, DP: double positive T cells, imCD4SP: immature CD4 single positive T cells, Prec: Treg precursor cells, tTreg: thymic Treg cells, Tconv: conventional T cells. b The gene expression profile of the Treg-associated genes based on the deposited RNA-seq data. Relative expression level of each gene at each developmental stage is shown.

Case 2: Zhou X, Motta F, Selmi C, Ridgway WM, Gershwin ME, Zhang W. Antibody glycosylation in autoimmune diseases. Autoimmun Rev. 2021 May;20(5):102804. doi: 10.1016/j.autrev.2021.102804. Epub 2021 Mar 14. PMID: 33727152; PMCID: PMC8058319.

Since glycosylation has become better understood, more data on IgG and its subclass structures are available for autoimmune diseases. In this review, the authors looked at the role of Ig glycosylation in autoimmunity: its modulation of the immune system, and its potential as a biomarker of disease.

Fig3. Immunoregulation pathways of antibody glycosylation in autoimmune diseases. b) Increased sialylation or fucosylation of antibody promote binding affinity to activating receptor FcγRIIIa, which mediates ADCC; Increased galactosylation of antibodies promotes binding affinity to C1q, which mediates CDC; Increased galactosylation or sialylation of antibody promotes binding affinity to FcγRIIa, which mediates ADCP; Decreased terminal mannose, increased galactosylation or sialylation of antibody promotes binding affinity to FcRn, which determines antibody half-life. Antibody effector functions play a role in initiation, development, and pathology of autoimmune diseases. G0, agalactosylated N-linked glycans; G1/2, singly galactosylated or digalactosylated N-linked glycans; G1, singly galactosylated N-linked glycans; G2, digalactosylated N-linked glycans.

Related Resource