What are the subclasses of IgG?

IgG is composed of four subclasses: IgG1, IgG2, IgG3, and IgG4 [1-9].

What is the difference between IgG subclasses?

Another structural difference between the human IgG subclasses is the linkage of the heavy and light chain by a disulfide bond. This bond links the carboxy-terminal cysteine of the light chain to the cysteine at position 220 (in IgG1) or at position 131 (in IgG2, IgG3, and IgG4) in the CH1 domain (Figure 2A).

Which IgG subtype constitutes most of total IgG?

IgG protein is comprised of molecules of 4 subclasses designated IgG1 through IgG4. Each subclass contains molecules with a structurally unique gamma heavy chain. Of total IgG, approximately 65% is IgG1, 25% is IgG2, 6% is IgG3, and 4% is IgG4.

What is IgG type?

IgG is the type of immunoglobulin most commonly found within human serum and can be broken down into four sub-classes: IgG1, IgG2, IgG3, and IgG4. IgG’s make up 10-20% of human plasma and were discovered in the 1960’s after studies were performed on rabbit antisera against human IgG proteins.

What are the different types of IgG antibodies?

There are five immunoglobulin classes (isotypes) of antibody molecules found in serum: IgG, IgM, IgA, IgE, and IgD.

IgA Antibodies (Immunoglobulin A)
IgD Antibodies (Immunoglobulin D)
IgE Antibodies (Immunoglobulin E)
IgG Antibodies (Immunoglobulin G)
IgM Antibodies (Immunoglobulin M)

What does IgG subclass 3 do?

For example, the IgG1 and IgG3 subclasses contain antibodies against serious bacterial infections such as diphtheria and tetanus, as well as antibodies against viral proteins.

Which subclass of IgG is most potent?

2.2. Deposition of C1q (binding to IgG-Fc) occurs with IgG1, 2 and 3, with IgG3 being the most effective; IgG4 is unable to interact with C1q (Table S1). Interestingly, C1q deposition efficiency does not directly correlate with CDC activity, in which IgG1 is the most potent IgG subclass (Bruggemann et al., 1987).

What is total IgG?

The main immunoglobulin (Ig) in human blood is IgG. This is the second most abundant circulating protein and contains long-term protective antibodies against many infectious agents. IgG is a combination of four slightly different types of IgG called IgG subclasses: IgG1, IgG2, IgG3 and IgG4.

Is IgG Type 1?

Herpes Simplex Virus (HSV) Type 1-Specific Antibodies, IgG.

What are the 5 antibody immunoglobulin classes?

The five primary classes of immunoglobulins are IgG, IgM, IgA, IgD and IgE. These are distinguished by the type of heavy chain found in the molecule. IgG molecules have heavy chains known as gamma-chains; IgMs have mu-chains; IgAs have alpha-chains; IgEs have epsilon-chains; and IgDs have delta-chains.

What does low IgG subclass 3 mean?

IgG3 deficiency is not a universally recognized immunodeficiency since the subclass is a minor component of the total IgG. The reports of IgG3 deficiency are associated with recurrent,chronic bacterial sinus or lung infection and a blunted response to bacterial vaccination (1,2).

What are the subtypes of the antibody IgG?

Antibody Isotypes & Subtypes. In mice the IgG class is divided into five sub-classes (IgG1, IgG2A, IgG2B, IgG2C and IgG3) and in rat there are four (IgG1, IgG2A, IgG2B, IgG2C). Sub-class nomenclature has arisen independently for each species and so there is no general relationship between the sub-classes from each species.

What are the functions of the 4 IgG subclasses?

Based on their structure, the 4 IgG subclasses can initiate different effector function such as complement activation, recruitment of various cells by Fc receptors, and agonistic signaling.

Can a deficiency of IgG affect more than one subclass?

IgG subclass deficiencies affect only IgG subclasses (usually IgG2 or IgG3), with normal total IgG and IgM immunoglobulins and other components of the immune system being at normal levels. These deficiencies can affect only one subclass or involve an association of two subclasses, such as IgG2 and IgG4.

What are the differences between IgG1 and IgG4?

IgG1 and IgG4 contain two inter-chain disulphide bonds in the hinge region, IgG2 has 4 and IgG3 has 11. Details of the functional differences between the IgG sub-classes in human will be described in the section on Fc effector function.