Immunodeficiences

Failure of the immune system's humoral or cell-mediated response, often due to intrinsic or extrinsic defects

Immunodeficiency caused by external factors, like stress or malnutrition

Immunodeficiency from genetic defects in immune cell development.

Primary is genetic, secondary is external.

Recurrent infections in a stressed, malnourished animal.

Immune cell development issues can begin with stem cells or the creation of neutrophils and macrophages.

In addition to stem cells, there are issues at lymphoid/myeloid lineage differentiation, and T/B cell development.

Chronic or repeated infections (especially in young animals or littermates) can signal a primary immunodeficiency issue.

To pinpoint the specific part of the immune system that's not working properly.

These are the parts of the immune system that we test to figure out what's wrong, like cell-mediated immunity and humoral immunity.

Two main types of immune responses. Cell-mediated relies on T cells attacking directly, while humoral uses B cells to produce antibodies.

Using a full panel means checking all the important components of the immune system to get a complete picture.

The process of pinpointing the exact location of the immune system problem, which could be a component or a specific cell type.

A rare genetic disorder caused by a mutation affecting lysosomal trafficking, leading to abnormally large lysosomes. This causes defects in various cell types, including neutrophils, monocytes, NK cells, and melanocytes.

In Chediak-Higashi Syndrome, the mutation disrupts the movement of lysosomes within cells, leading to their abnormal accumulation and fusion.

Chediak-Higashi Syndrome presents with a variety of symptoms, including albinism (melanocyte defects), increased susceptibility to infections (neutrophil/monocyte/NK cell defects), and bleeding problems (endothelial defects).

In Chediak-Higashi Syndrome, these cells have impaired function due to the lysosomal trafficking defect, leading to increased risk of infections and tumors.

Chediak-Higashi Syndrome can also cause problems with blood vessels, leading to easy bruising and bleeding.

A single genetic change in the CD18 gene, specifically the beta chain, causing a faulty protein to be made. This affects how CD18 and the immune system works.

The CLAD mutation messes up the CD18 protein's structure, specifically its disulfide bonds. This makes the CD18 protein unable to function as it should.

The CD11b protein, which normally sits on the cell surface, is not expressed when CD18 is faulty. CD11b needs the CD18 beta chain to function properly.

The faulty CD18 protein affects immune cells' ability to adhere and migrate to infection sites. This makes the immune system less effective at fighting infections.

CLAD stands for Canine Leukocyte Adhesion Deficiency. This is a genetic disorder that affects the immune system in dogs.

An autosomal recessive disease caused by a mutation in the AP3β1 gene, leading to cyclic neutropenia due to impaired maturation of myeloid progenitor cells in the bone marrow.

The gene responsible for normal trafficking of granular proteins (like elastase) to cytoplasmic granules during hematopoiesis. A mutation in this gene causes Canine Cyclic Neutropenia.

Immature cells in the bone marrow that are destined to become neutrophils and other myeloid cells. Their maturation is disrupted in Canine Cyclic Neutropenia.

A condition characterized by an abnormally low number of neutrophils in the blood, leading to increased susceptibility to infections.

A common consequence of Canine Cyclic Neutropenia due to the compromised immune response, especially in young animals.

A genetic disorder in horses caused by a mutation in the gene for DNA-PKcs, resulting in a loss of 967 amino acids and impaired immune function.

The mutation in SCID in horses specifically removes 5 nucleotides in the coding region of DNA-PKcs, leading to the loss of 967 amino acids in the protein.

The mutation in SCID disrupts the recombination of TCR and BCR variable regions, preventing lymphocytes from recognizing antigens. This results in a low production of T and B lymphocytes.

Horses with SCID exhibit very low numbers of T and B lymphocytes in circulation, making them susceptible to infections.

The lack of functional T and B lymphocytes in SCID leads to a compromised immune system. This makes horses susceptible to a wide range of infections and diseases.

Horses with SCID have a severely impaired immune system due to the lack of functional T and B lymphocytes. This makes them vulnerable to various infections.

SCID in horses is diagnosed by identifying three key factors: low circulating lymphocytes, absence of IgM before suckling, and histologically typical signs like hypoplasia of lymphoid organs.

Horses with SCID are at high risk of developing various infections and diseases due to their compromised immune system. This can lead to serious health complications and even death.

The diagnosis of SCID in horses is important due to their value as animals. Understanding the condition helps in managing their health and making informed breeding decisions.

A genetic disorder in Jack Russell terriers caused by a defect in the gene coding for DNA-PKsc, leading to a lack of immune function.

SCID in dogs results in lymphopenia, agammaglobulinemia, and the absence of a thymus and lymphoid tissue.

SCID in dogs is inherited in an autosomal recessive manner, meaning both parents must carry the defective gene for their offspring to be affected.

SCID in dogs disrupts the development of immune cells, leading to a lack of T and B lymphocytes.

Mutations in the gene encoding the γ chain of the IL-2 receptor (IL-2R) cause X-SCID. This γ chain is crucial for various cytokine receptors.

In X-SCID, lymphocytes lack reactivity to IL-2 and other cytokines, resulting in a lack of mature T lymphocytes.

Basset Hounds have a 4-nucleotide deletion causing a premature STOP codon, while Corgis have a cytosine insertion creating a STOP codon, both leading to non-functional proteins.

The most common type of selective immunoglobulin deficiency, where the body lacks the ability to produce IgA antibodies.

A type of selective immunodeficiency where specific subclasses of IgG antibodies are missing, leading to increased susceptibility to infections.

A block in the differentiation of B cells into IgA or IgG antibody-producing plasma cells, often due to genetic mutations in the constant region genes.

These dogs are commonly affected by selective IgG deficiency, meaning they lack certain IgG antibodies.

Dobermanns are known for their selective IgM deficiency, leading to a compromised immune response.

In humans, CVID can be genetic, specifically caused by a defect in the ICOS molecule. This molecule helps with proper lymphocyte stimulation.

CVID involves a problem with B cell function. It's often linked to a lack of proper stimulation from helper T cells, leading to insufficient antibody production.

CVID in horses is generally caused by a lack of proper helper T cell stimulation, while in humans, it's often caused by genetic defects in the ICOS molecule, which plays a crucial role in lymphocyte activation.

A decrease in the number of lymphocytes in the blood, which are crucial for immune responses.

Low levels of immunoglobulins (antibodies) in the blood, which are essential for fighting infections.

A situation where a viral infection weakens the immune system and makes the body more vulnerable to other infections.

Viruses can directly damage lymphatic organs, like lymph nodes and bone marrow, which are key sites for immune cell development and function.

In addition to reducing lymphocyte numbers, viral infections can also decrease the ability of lymphocytes to respond effectively to stimulation by antigens or mitogens.

Viruses can directly damage primary or secondary lymphatic organs, like lymph nodes and bone marrow, which are important sites for immune cell development and function. This can lead to decreased lymphocyte numbers and reactivity, weakening the immune response.