sumarry components of immune

Cortex, medulla, and paracortex.

Macrophages act as antigen presenting cells (APCs) by capturing and processing antigens, then presenting them with MHC class II molecules to helper T cells.

Variable and constant region.

In the submucosa of the intestinal wall.

Only 2–5%.

Tolerance to self-antigens mediated by the thymus, preventing autoimmunity.

10–15%.

Dimeric IgA antibodies.

Lymphocytes (B cells, plasma cells, T helper cells) and macrophages.

Specialized T cells found in the epithelial layer of the intestinal mucosa.

They act as a portal for microbes to enter the immune system.

Presenting peptide antigens to CD8 T cells.

On the surface of all nucleated cells except sperm cells and platelets.

Follicles found before antigenic stimulus, mainly containing resting B cells.

They divide and become activated, differentiating into plasma cells and memory B cells.

Specialized epithelial cells with long membrane extensions that surround many thymocytes.

They attract precursor T cells (progenitor T cells) from bone marrow.

They become activated, enhancing their phagocytic ability and increasing cytokine production against intracellular bacteria, virus-infected cells, and tumor cells.

A category of white blood cells characterized by the presence of granules in their cytoplasm.

Less than 30 kDa.

It is the site of hematopoiesis, where almost all blood cells originate from pluripotent hematopoietic stem cells.

They undergo negative selection if they react to self-antigens.

It is believed to be the eosinophil chemotactic factor.

Examples include enzymes, free radicals, cytokines, growth factors, and coagulation factors.

IFN-γ.

DO, DM, LMP, and TAP, which help in antigen processing and presentation.

A few days to a few weeks.

One α chain and one β chain, each consisting of two domains.

Phagocytosis.

Loose clusters of lymphoid cells and organized structures like tonsils and Peyer's patches.

They are present in lymphoid follicles and differ from other dendritic cells in their specific location and function.

IL-1, IL-8, TNF-α.

Antigenic peptides presented with MHC-II molecules.

MHC coded proteins found on the surface of human cells.

Corticosteroids and prostaglandins.

T lymphocytes, B lymphocytes, and natural killer (NK) cells.

Resting B and T lymphocytes that have not interacted with any antigen.

Composed of an α chain and β2 microglobulin, with three extracellular domains (α1, α2, α3).

Hematopoietin family, interferon family, chemokine family, and tumor necrosis factor family.

The central area containing dividing B cells of various stages, where B cell activation occurs.

Promote development of adaptive immunity and promote responses of innate immunity.

It is the site of proliferation and maturation of T cells.

A group of genes coding for host cell surface molecules that bind to peptide fragments from pathogens.

Central (primary) lymphoid organs and peripheral (secondary) lymphoid organs.

It is strongly associated with ankylosing spondylitis, increasing risk by 90 times.

An immunodeficiency disorder characterized by congenital aplasia of the thymus.

They are specialized antigen presenting cells that capture, process, and present antigenic peptides to helper T cells.

Presenting peptide antigens to CD4 T cells.

Recognition: Attachment of the microbe to receptors on the macrophage.

MHC class II molecules are essential for presenting antigenic peptides to helper T cells, facilitating their activation.

Increases expression on resting B cells.

IgM and IgD initially, followed by IgG, IgA, and IgE with high affinity.

In the bone marrow, independent of exposure to antigen.

Mucosa-associated Lymphoid Tissue.

Synergism (augmenting each other's action) and antagonism (opposing each other's action).

Presented antigens.

Granules rich in histamine and other mediators.

Antigen recognition.

Induces proliferation of activated T H cells, T C cells, and some NK cells.

TH1, TH2, and TH17 cells.

Intracellular antigens presented with MHC-I molecules.

Phagocytes (macrophages, neutrophils, eosinophils, basophils), dendritic cells, mast cells, and platelets.

The earliest bone marrow cells of B cell lineage that do not produce immunoglobulins but express a heterodimer Ig D /Ig E.

A separate lymphoid lineage.

Phagocytosis and antigen presentation.

8 hours.

It promotes inflammatory responses, fever, and activates helper T cells.

50–70%.

In the thymus.

They can undergo positive selection if their DE receptors recognize MHC molecules.

Bare lymphocyte syndrome.

It interacts with the CD4 molecule of helper T cells during antigen presentation.

Oxygen independent killing.

Two chains (D and E) with three regions: extracellular domain, transmembrane domain, and cytoplasmic domain.

CD127 (IL-7R).

Cytokines are inducible and produced after cell activation, while growth factors are produced constitutively.

MHC class I presents endogenous antigens; MHC class II presents exogenous antigens.

A series of effects mediated by different cytokines where one cytokine acts on a target cell to produce another cytokine.

Activated lymphoblasts that function to eliminate antigens.

They are the principal phagocytes of innate immunity.

Increased incidence of bacterial sepsis, especially from capsulated bacteria.

It decreases, and after puberty, hematopoiesis is mostly confined to axial bones.

In skin, connective tissues of various organs, and mucosa.

They respond to antigens that are processed and presented by antigen presenting cells.

On the short arm of chromosome-6.

MHC class I is present on all nucleated cells, while class II is present on antigen presenting cells (APCs).

They become activated and transform into lymphoblasts.

Both D and E chains must complex with the CD3 molecule.

White pulp and red pulp.

In the liver.

They originate from bone marrow, possibly developing from a separate lineage or from the macrophage lineage.

CD4+ helper T cells and CD8+ cytotoxic T cells.

Short, as they are dormant in the G0 phase.

They inhibit various components, leading to suppressed expression.

A small subset of T cells that do not require antigen processing and MHC presentation.

Lymphokines, monokines, interleukins, and chemokines.

Autocrine, paracrine, and endocrine effects.

They transform into activated B cells (lymphoblasts) and differentiate into effector B cells or memory B cells.

95%.

Memory cells can rapidly transform into effector cells upon subsequent antigenic challenge.

Either CD4 or CD8 molecules, becoming single positive mature T cells.

CIITA and RFX.

Acts as a physiological barrier, clearing microbial antigens through stimulation of T and B cells.

Phagolysosome.

Promotes B cell activation and proliferation, and induces class switch to produce IgE, IgG4, IgG1.

Over 1000 kbp.

They are found mostly in the peritoneal cavity, coated by surface markers IgM and CD5, but lack IgD.

Lymphoid organs, cells of the immune system, and cytokines.

To filter blood and destroy old or defective red blood cells.

It binds to the CD8 molecule on cytotoxic T cells during antigen presentation.

Free (wandering) macrophages and fixed macrophages.

T H cells and macrophages.

Lymphocytes of the thymus, specifically immature cortical thymocytes.

Lymph nodes, spleen, and mucosa-associated lymphoid tissue (MALT).

HLA-A, HLA-B, and HLA-C.

To peripheral lymphoid organs like lymph nodes and spleen.

Dendritic cells are nonphagocytic and are the most efficient APCs, while macrophages are phagocytic.

70–80%.

Effector T cells are active and found in inflamed tissues, while naive T cells are dormant.

Promotes B cell proliferation and antibody production.

Regulating the immune system and providing tolerance to self-antigens.

By expressing the μ heavy chain.

Receptor editing and negative selection.

Different cytokines producing the same effect on the same target cell.

Antibody-secreting cells that are large, oval, and have a short life span of two to three days.

Macrophages are 5–10 times larger, contain more organelles, produce more enzymes and cytokines, have greater phagocytic activity, and live longer in tissues.

T cell precursors that do not express CD4 and CD8 surface markers.

The cleft between the α1 and β1 domains.

They produce IL-17 and IL-22, recruiting neutrophils and contributing to autoimmune diseases.

They determine compatibility between graft and host tissues, affecting acceptance or rejection.

95%.

At puberty.

Deficiency leads to autoimmune diseases like IPEX syndrome.

It prevents autoimmunity by ensuring that immature B cells do not react to self-antigens.

Soluble products secreted from various cells of the immune system, including interleukins and interferons.

Chemical substances that serve as messengers in the immune system.

The same cytokine having different actions on different target cells.

B cells present at the edges of lymphoid follicles of the spleen, produced in response to polysaccharide antigens.

They express light chains and proliferate from Pre-B cells.

Mediating humoral immunity.

A heavy chain μ and its light chain, forming a complete IgM molecule complexed with heterodimer Ig D /Ig E.