Contact Sensitization Flashcards Preview

Dermal > Contact Sensitization > Flashcards

Flashcards in Contact Sensitization Deck (19)
1

4 types of hypersensitivity reactions

I: IgE mediated (immediate)
II: Cytotoxic/Cytolytic (IgG, IgM)
III: Immune complex-mediated
IV: T-lymphocyte mediated (delayed)

2

Type I hypersensitivity reaction:

IgE bound to mast cell
antigen binds--> mast cells degranulate
histamine released

3

Type III hypersensitivity reaction:

Immune complex activated, attracting neutrophils
products of neutrophils cause damage to tissues

4

In a Type IV hypersensitivity reaction, antigens are presented as

peptides on MHC molecules

5

T-lymphocyte activation causes ______, which generates _______

cytokine release
inflammation

6

T-cells release

Perforin, Protease
both eventually lead to apoptosis

7

In skin sensitization, chemical allergen provokes _________

Cutaneous immune response

8

Contact sensitization will develop if

the cutaneous immune response provoked by chemical allergen is of required magnitude

9

Skin sensitizing agents must be either ____ or _____

inherently protein-reactive
metabolized in skin to be protein reactive

10

After epidermal LC internalize and process the inducing allergen,

a proportion of LC local to site of exposure is stimulated to migrate from epidermis to lymph nodes

11

LC that move from skin undergo

functional maturation so they accumulate as immunostimulatory DC to present antigen effectively to responsive T lymphocytes

12

Antigen-driven T lymphocyte activation is characterized by

cell division/differentiation

13

Cellular basis for skin sensitization (immunologic memory) is represented by

selective clonal expansion of T lymphocytes

14

Clonal proliferation of sensitized T-cells occurs in ______, and T-cells mount reaction ________

-Lymph nodes
-after returning to epidermis

15

Most important determinant of acquisition of sensitization

amount of allergen per unit area of skin (rather than total amount delivered)

16

In HRIPT, "induction phase" refers to the time

until T cells have been sensitized

17

"elicitation phase" of HRIPT refers to the time

after T-cells are sensitized until a reaction is seen

18

Minimum number of panelists for HRIPT protocol

200

19

_______ days after application of final induction patch, HRIPT involves application of challenge patches to:

10-21
previously unpatched sites