T cells good or bad - function and malfunction

By SWA

 Besides Foxp3, there are many other Tregs-signature genes, coding factors such as Il2ra (CD25), Ctla4 (CD152), Tnfrsf18 (GITR), Ikzf2 (Helios), and Ikzf4 (Eos), which are believed to play an important role in Tregs function.

T cells are a type of white blood cell that play a crucial role in the immune system, particularly in the adaptive immune response. There are various types of T cells, each with specific functions, and among them are regulatory T cells (Tregs), which are vital for maintaining immune tolerance and preventing autoimmune diseases.

The function of Tregs is largely governed by the expression of certain signature genes. Here's a brief overview of the genes you mentioned and their roles:

  1. Foxp3: This is a master regulatory gene that is crucial for the development and function of Tregs. Mutations in Foxp3 can lead to severe autoimmune diseases, as Tregs lose their ability to regulate immune responses properly.

  2. Il2ra (CD25): This gene encodes for the alpha chain of the IL-2 receptor, which is highly expressed on Tregs. IL-2 signaling is critical for the survival and function of Tregs.

  3. Ctla4 (CD152): CTLA-4 is an inhibitory receptor expressed by T cells, especially Tregs. It helps to suppress immune responses by down-regulating the activity of effector T cells.

  4. Tnfrsf18 (GITR): GITR is another receptor expressed on the surface of Tregs. Its activation can modulate the suppressive function of Tregs and also influence other immune cells.

  5. Ikzf2 (Helios) and Ikzf4 (Eos): These genes encode transcription factors that are involved in the development and function of Tregs. Helios, for instance, is thought to mark a particularly stable and potent subset of Tregs.

Malfunction of T cells, particularly Tregs, can lead to either an excessive or insufficient immune response. For example, if Tregs are overactive or too numerous, they might suppress the immune response excessively, leading to an increased susceptibility to infections and possibly cancer. On the other hand, if Tregs are underactive or deficient, it can lead to uncontrolled immune responses, resulting in autoimmune diseases where the body's immune system attacks its own tissues.

Cytotoxic CD8 T cells carry out their killing function by releasing two types of preformed cytotoxic protein: the granzymes, which seem able to induce apoptosis in any type of target cell, and the pore-forming protein perforin, which punches holes in the target-cell membrane through which the granzymes can enter.
T cell-mediated cytotoxicity: https://www.ncbi.nlm.nih.gov/books/NBK27101/

Understanding and manipulating these genes and their products are areas of intense research, especially for therapeutic purposes in autoimmune diseases, transplantation, and cancer therapy.

Reference;

Regulatory T Cells-Related Genes Are under DNA Methylation Influence 
 
Foxp3 in control of the regulatory T cell lineage
 
A function for interleukin 2 in Foxp3-expressing regulatory T cells
 
CTLA-4 control over Foxp3+ regulatory T cell function
 
 

 

Comments

Post a Comment

Popular posts from this blog

Schnitzler Syndrome: A Rare Autoinflammatory Disorder

By SWA
Schnitzler syndrome is a rare, chronic autoinflammatory disease characterized by chronic urticaria (hives), recurrent fever, joint pain, and monoclonal gammopathy (abnormal proteins in the blood). First described by Dr. Liliane Schnitzler in 1972 , this condition is often misdiagnosed, leading to years of untreated symptoms before a correct diagnosis is made. The case report, " A 58-Year-Old Woman With Urticaria, Fever, and Joint Pain " , describes a case that closely aligns with my own experience with this challenging disorder. Key Features of Schnitzler Syndrome Schnitzler syndrome presents with a characteristic set of symptoms, though not all patients experience them in the same way: Chronic Urticaria (Hives) – Persistent, non-itchy or mildly itchy red patches that do not respond to antihistamines. Monoclonal Gammopathy (IgM or IgG type) – Abnormal monoclonal immunoglobulin detected in the blood (most commonly IgM ). Recurrent Fever – Unexplained fever episodes, often...
Read more

Dysferlin Protein: Key Roles, Genetic Locations

By SWA
Image
The purpose of this article is to share and discuss the details of a new discovery, which is highlighted within: CRISPR-Cas9: A Breakthrough Tool to Repair the DYSF Gene The dysferlin protein plays an essential role in maintaining the integrity of muscle cell membranes, particularly in tissues that endure significant mechanical stress, such as skeletal and cardiac muscles . Encoded by the DYSF gene , dysferlin is indispensable for repairing damaged cell membranes after injury caused by muscle contraction or external forces. This article explores the main locations where dysferlin is produced, its role in muscle repair, and supportive nutritional and therapeutic strategies for individuals with dysferlin deficiency, such as those affected by dysferlinopathies (e.g., Limb-Girdle Muscular Dystrophy Type 2B or Miyoshi Myopathy). Currently, there is no definitive answer as to why the severity of dysferlin protein expression or depletion varies. Do pathogens play a role in the methylation o...
Read more

Toxic Skin Condition Post-mRNA COVID-19 Vaccination

By SWA
Image
Identifying Severe Skin Conditions Post-Vaccination Following administration of the BioNTech mRNA vaccine, a small subset of individuals may develop severe and complex reactions. These reactions are often misdiagnosed or misunderstood due to their rarity and diverse presentation. This essay examines a case characterized by severe skin conditions, systemic symptoms, and complications such as hypercalcemia and crystal formation. It highlights the need for accurate diagnosis, holistic management, and increased awareness of these rare but significant vaccine-related adverse events. Initial Symptoms and Misdiagnoses Severe symptoms began shortly after the first dose of the BioNTech vaccine, initially presenting as petechiae, diagnosed by a rheumatologist. However, following the second dose, symptoms rapidly escalated, resulting in intense burning pain and thinning of the skin. The skin on the legs and thighs became paper-thin and could tear with the slightest touch, with the affected area e...
Read more