What is complement-dependent cellular cytotoxicity?

CDC is the mechanism by which antibody-coated target cells recruit and activate components of the complement cascade, leading to the formation of a Membrane Attack Complex (MAC) on the cell surface and subsequent cell lysis.

Which antibody is complement-dependent?

Complement-dependent cytotoxicity (CDC) is an effector function of IgG and IgM antibodies.

What is ADCC and CDC?

Two important mechanisms by which antibody drugs kill targeted tumor cells are antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC).

What is complement-dependent cytotoxicity test?

Complement-dependent cytotoxicity (CDC) was the first technique routinely used for HLA antibody detection and for the crossmatch test (Figure 10-5). In this assay, lymphocyte target cells are used to detect complement-fixing IgG and IgM antibodies present in a patient’s serum after the addition of rabbit complement.

How is complement-dependent cytotoxicity measured?

We can perform CDC assays by flow cytometry wherein cells are stained with an intercalating dye to identify dead targets. In these experiments, cells are cultured with antibody and serum, followed by staining with the dye and analysis on the cytometer.

What is toxic to cells?

From Wikipedia, the free encyclopedia. Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (Bitis arietans) or brown recluse spider (Loxosceles reclusa).

Is cytotoxic a complement?

Antibodies that contain the Fc portion of the human IgG1 can activate complement-mediated cell death. One way in which they do this is via direct complement killing of tumor cells by the membrane attack complex, a process usually called complement-dependent cytotoxicity.

What cells do ADCC?

ADCC by four major immune effector cells: macrophages/resident monocytes, NK cells, neutrophils, and eosinophils. The target cell may either be microbe infected or a tumor cell that expresses the antigen recognized and bound by the antibody.

How do you test for cell toxicity?

Cell culture can be used to screen for toxicity both by estimation of the basal functions of the cell (i.e. those processes common to all types of cells) or by tests on specialized cell functions (Ekwall, 1983b).

What does neurotoxicity mean?

Definition. Neurotoxicity occurs when the exposure to natural or manmade toxic substances (neurotoxicants) alters the normal activity of the nervous system. This can eventually disrupt or even kill neurons, key cells that transmit and process signals in the brain and other parts of the nervous system.

How is complement dependent cytotoxicity measured?

What is required for an effective ADCC?

ADCC requires an effector cell which classically is known to be natural killer (NK) cells that typically interact with immunoglobulin G (IgG) antibodies. However, macrophages, neutrophils and eosinophils can also mediate ADCC, such as eosinophils killing certain parasitic worms known as helminths via IgE antibodies.

How does complement dependent reaction work in red blood cells?

Complement dependent reactions: Antibody is directed against antigen on cells (such as circulating red blood cells) or extracellular materials (basement membrane). The resulting Ag-Ab complexes activate complement (via the classic pathway), leading to cell lysis or extracellular tissue damage.

What happens when complement is added to a reaction?

Complement is added to the reactions and if specific antibodies are bound on the cells the complement cascade is initiated and cell death occurs. Special stains are added to identify dead cells from live cells and the cells are visualized microscopically.

What are the regulatory mechanisms of the complement system?

Complement regulation. The complement system has the potential to be extremely damaging to host tissues; hence regulatory mechanisms are required to restrict the complement pathway. Various plasma and cell membrane proteins regulate complement activation by inhibiting different steps in the cascade.

Which is a possible mechanism of complement dependent cytotoxicity?

Complement-dependent cytotoxicity assay of peripheral blood lymphocytes is a possible mechanism by which LCA may mediate in vivo lymphocytolysis. But, to date, a direct relationship between LCA and lymphopenia was not reported.