Immunological Mechanisms of Disease Flashcards
What is insulitis in terms of immunology?
Infiltration of the islet of langerhans via Mononuclear cells and CD8+ T Cells (HLA Class II)
What genes play a role in the presentation of insulin Ags to CD8+ T Cells?
HLA region (MHC gene on chromosome 6)
What genetic factor is responsible for the Ag (that plays a role in the autoimmune response)?
Insulin Gene (Chromosome 11)
What gene is responsible for regulation of the autoimmune response?
CTLA-4 gene (CHromosome 2)
What are the high risk alleles for developing T1D?
Class II HLAs: DQ2/DQ8 & DR3/DR4
What haplotypes are found in more than 90% of individuals diagnosed with T1D?
DR3/DQ2 & DR4/DQ8
HLA Class II molecules that lack ______ of the ______ are often found in individuals with T1D
Asp57 of the Beta chain
Heterozygous Genotypes *** are most common in children diagnosed with T1D; prior to the age of 5 y.o
DR3/DR4
What HLA Class II haplotypes confer dominant protection?
DR2/DQ6
Where is the Ag of insulin located in the insulin gene itself?
Region containing VNTR (Variable number of tandem repeats) in the promoter region of the insulin gene
VNTR (Variable number of tandem repeats) polymorphism in classified into three classes; Class I, II, & III. Which class is associated with lower mRNA syntheis of insulin? Also, what is the result of this defect?
1) Class I 2) Lower Ag (insulin) synthesis –> Lower presentation of Ags in the Thymus –> failure of deletion of self reactive T cells –> some of these T Cells can go into the periphery (breaking central tolerance)
What is the correlation between breast feeding v.s cow’s milk and the development of T1D?
Early exposure to Cow’s Milk may increase susceptibility to developing T1D; as Cow’s Milk has much less insulin than does human milk
The risk of developing T1D is higher in those with what two factors?
1) Gluten mediated enteropathy 2) Vitamin D: Deficiency
What products from Streptomyces are cytotoxic for B Cells?
Streptozocin and Balifomycin A1
{Street Ball is A1}
Viruses can elicit an autoimmune reaction via molecular mimicry in which T cells can cross react to viral antigens and self antigens. What two viruses can elicit this reaction?
Mumps and Rubella
