Genetic and Environmental Influences on Type I Hypersensitivity

Question 1

development of IgE responses and allergy appears to depend on complex interactions between

Answer 1

genetic factors and environmental triggers

Question 2

Some of these genes affect the structure of the
epithelium lining in places where allergens can enter the body, such as the

Answer 2

skin, gastrointestinal tract, and respiratory tract

Question 3

Another group of genes play a role in recognition of the antigen by the_____ ______ _______once it has entered through the epithelial barriers

Answer 3

innate immune system

Question 4

Defects in these genes, which code for pattern recognition receptors such as _____ and the ____________, can affect cell interactions with antigens in the initial phases of immune defense.

Answer 4

CD14 and the Toll-like receptors (TLRs)

Question 5

A third group of genes can influence susceptibility to allergic disorders by affecting aspects of the _____ ______ ______, such as

Answer 5

adaptive immune response; cytokine production and the ability of T cells to differentiate into Th1 cells, Th2 cells, and T regulatory cells.

Question 6

Aberrations in these genes can result in dysregulation of the immune response, inducing production of cytokines that promote IgE synthesis, such as

Answer 6

IL-4 and IL-13

Question 7

allergy and asthma appear to be associated with certain

Answer 7

HLA class II genes

Question 8

coded for by these histocompatibility genes are known to play a role in antigen presentation and may influence the tendency to respond to specific allergens

Answer 8

HLA-D molecules

Question 9

genes that play a role in modulating the inflammatory response can influence the long-term consequences of allergies by affecting the process of

Answer 9

tissue remodeling and repair

Question 10

The increased prevalence of allergy in industrialized regions may be due, in part, to

Answer 10

increased hygiene practices and use of
antibiotics

Question 11

exposure to stress, variations in physical factors such as temperature, and contact with environmental pollutants such as ___ ____ ____ ____ ____ can intensify clinical manifestations of allergy in susceptible
individuals

Answer 11

cigarette smoke and diesel exhaust fumes

Question 12

*Multiple studies in Europe, the United States, and South America have provided evidence for a protective
*studies indicate that in utero or early life exposure to the diverse microbial populations in a farming environment provides protection against allergies by inducing development of
regulatory T cells and by directing the immune system toward beneficial Th1 responses and away from Th2 atopic reactions

Answer 12

“farm effect”