Immunoglobulin: Isotypes, Allotypes and Idiotypes

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ImmunoglobulinIsotypes, Allotypes and Idiotypes
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Immunoglobulin Isotypes

• Definition - Antigenic determinants that
  characterize the classes and subclasses of heavy
  chains and types and subtypes of light chains

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Immunoglobulin Isotypes
Human IgM
Reacts with IgM, IgG, IgA, IgD, IgE
??
antiserum
React with IgG, IgA, IgD and IgE
??
Absorbed antiserum
Reacts only with IgM
Recognizes determinants specific for ? heavy
chains (isotypes)
??
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Immunoglobulin Isotypes

• Definition

• Location

• Occurrence
• Importance
• Ig levels
• B cell tumors
• Immunodeficiencies

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Immunoglobulin Allotypes

• Definition - Antigenic determinants specified
• by allelic forms of the Ig genes

• Source of anti-allotypic Abs

• Location

• Occurrence

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Human Immunoglobulin Allotypes

• Nomenclature
• G1m(3)
• Km(1)

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Human Immunoglobulin Allotypes

• Genetics (alleles)
• Co-dominant
• autosomal genes

Km(1)/Km(3) X Km(1)/Km(1)
Km(1)/Km(1) and Km(1)/Km(3)

• Allelic exclusion

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Human Immunoglobulin Allotypes

• Genetics (pseudoalleles)
• Co-dominant

G1m(17)
G1m(1)
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355-358
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Immunoglobulin Allotypes

• Definition
• Location
• Occurrence
• Importance
• Monitoring bone marrow grafts
• Forensic medicine
• Paternity testing

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Immunoglobulin Idiotypes

• Definition - Unique antigenic determinants
  present on individual antibody molecules or on
  molecules of identical specificity

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Immunoglobulin Idiotypes
Strain A Mouse
Anti-DNP Ab
DNP-BSA
Ab against combining site of anti-DNP Ab
Strain A Mouse
Purified anti-DNP Ab
??
Antigenic determinants created by the HVR
Idiotypes
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Immunoglobulin Idiotypes

• Definition
• Location

IgG1 (kappa) Person 1 anti-B
IgG1 (kappa) Person 1 anti-A
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Immunoglobulin Idiotypes

• Definition
• Location
• Importance
• V region marker
• Regulation of immune responses

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Regulation by Id/anti-Id


Ag
Id
anti-Id
anti-anti-Id
-
-
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Immunoglobulin Idiotypes

• Definition
• Location
• Importance
• V region marker
• Regulation of immune responses
• Vaccines

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Anti-Idiotype Vaccines
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Immunoglobulin Idiotypes

• Definition
• Location
• Importance
• V region marker
• Regulation of immune responses
• Vaccines
• Treatment of B cell tumors (T cell)