Adaptive immunity Flashcards
Large Glycoproteins that recognize a specific Antigen
Immunoglobulin
Types of immunoglobin
Membrane bound-b cell receptors
Non-membrane bound-antibody
Parts of an antibody
Heavy(long) and light(short) chain
how heavy and light chain connect
Disulfide bond
How many different types of heavy and light chains can a b cell produce
one type of each
Papain turns an antibody into
2 Fab fragments and one Fc fragment
Where anitgen binds
Fab fragments
The Fc area of an antibody binds wehre
Fc receptors on innate immune cells
Where antigen binding occures
Variable region(different between antibodies) contain and light and heavy chain part
Are Immunoglobulins flexible
Yes, needs to move a bit to bind to antigens
Amino acid sequence that demonstrate extreme variability between different lg molecules
Hypervariable regions
Where the Hypervariable region is found
at least 3 areas of the variable region
length of the hypervariable region
5-7 amino acids longs
Role of the hypervariable regions
give rise to the enormous antigenic diversity associated with Ig molecules
Region of antigen with little variation
Constant region
changes in the Constant region leads to
change in size, charge, solubility, and structure of an Ig molecule
Different structures of Ig molecules
isotypes
Light chain isotypes
Kappa and Lambda
Role of Light Chain Isotypes
Contribute to diversity but not function
different heavy chain isotypes
Mu, Delta, Gamma, Epsilon, and alpha in addition to subclasses within
What is produced when a naive b cell first encounters an antigen
It will produce IgM
what can lead to class switching of isotypes
Genetic Rearrangements of the constant region
Structural Isoforms
Membrane-bound Ig
Secreted Ig
Secretory Ig
Where Secretory and Secreted Isoforms are found
Secretory- secretions (tears mucus)
Secreted-found in blood
Domain found on membrane-bound Ig
Cytoplasmic and Transmembrane domain
Secreted Ig lacks
Transmembrane and cytoplasmic donmains
Roll of Secretory component of Ig
Protection
Packages the Heavy and light chain Immunoglobins
the Smooth ER
When membrane bound immunoglobin binds to the membrane
In the ER and allways until it binds to cell membrane
Multiple immunoglobulins together
Polymeric Immunoglobulins
Most common Polymeric Immunoglobulins
igM=5
igA=2
Holds together Polymeric Immunoglobulins
J chain
How Secretory Immunoglobenulins enter the lumen
Bind to receptor, enter transport vesicle then enter the lumen of body tract
Because B Cell receptors don’t go far into the cytoplasm, what do they complex with to induce a response
Ig-alpha and Ig-beta and they use ITAM to induce a response
Exons vs introns
Coding
Non coding
What makes up the variable region of Immunoglobulin genes
Small DNA fragments call gene segements
Types of Gene segments
Variable, Diversity, Joining
What gene segment does the light chain not have
D segment
What is Somatic recombination
Random rearangement of the V, D, and J segments of the variable region
Where V, D, J recombination occures
in every naive B cell