23) Multiple Autoimmune Diseases Are Associated with Particular Alleles of MHC

question 15

Multiple Choice

23) Multiple autoimmune diseases are associated with particular alleles of MHC class II molecules. For example, individuals expressing HLA-DR2 are nearly 16 times more likely to develop Goodpasture's syndrome than individuals expressing other HLA-DR alleles. The evidence to date indicate that these associations between MHC class II alleles and specific autoimmune diseases are due to:

• A) Enhanced negative selection in the thymus mediated by disease-associated HLA alleles
• B) Allelic variations in non-MHC class II genes encoded in the HLA locus
• C) Differences in the peptide-binding properties of different MHC class II alleles
• D) Differences in the autoantigens expressed in males versus females with disease-associated alleles
• E) Differences in the development of FoxP3+ regulatory CD4 T cells in individuals expressing different alleles

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Definitions:

Appositional Growth

To place one layer of bone, cartilage, or other connective tissue against an existing layer.

Chondroblasts

Cells that produce the matrix of cartilage and eventually become chondrocytes, which are responsible for the maintenance of cartilage.

Chondrocytes

Cells found within cartilage tissue, responsible for maintaining the cartilaginous matrix.

Chondrocytes

Cells that are found in cartilage tissue and are responsible for the synthesis and maintenance of the cartilaginous matrix.