Iycee Charles de Gaulle Summary unclear, a multitude of inhaled organic particles

unclear, a multitude of inhaled organic particles

unclear, but evidence supports a role for both type III and
type IV immune responses.

occupational antigens. The exact pathophysiologic mechanism
of hypersensitivity pneumonitis remains

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!

order now

exaggerated immune response after exposure to a multitude of
inhaled organic particles or related

pneumonitis is a form of inflammatory lung disease that results from an

to the specific hapten results in rapid recruitment and
activation of memory-specific T cells.

dendritic cells, which then migrate to regional lymph nodes
and stimulate T cell production. Reexposure

have come in direct contact with a halpen. During the
sensitization phase, haptens are captured by

takes place in two phases, sensitization and elicitation. It
is usually confined to sites on the skin that

contact dermatitis is a type IV hypersensitivity reaction. The inflammatory

circulating IgG antibody.

completely understood but is believed to be the result of
localized contact of injected antigen with

form at the center of the lesion due to the release of
cytokines. The Arthus reaction mechanism is not

begin within one hour of an exposure. Lesions are typically
red, raised, and inflammed. Ulcers often

necrosis, usually in the skin. It is caused by repeated
local exposure to an antigen. Symptoms usually

Arthus reaction is a localized immune complex reaction associated with discrete

leukotrienes, that are responsible for rhinorrhea, sneezing,
nasal itching, and watery eyes.

in IgE production. IgE production, in turn, triggers the
release of mediators such as histamine and

cells by APCs. In the presence of cellular cytokines, B-cell
class switching occurs, resulting in an increase

aeroallergens are inhaled, they are deposited mainly on the
nasal mucosa where they are presented to T

allergic response in allergic rhinitis is located specifically in the nasal
mucosa. When

cause) of coronary artery disease.”

used in our text to explain etiology is the following,
“atherosclerosis often is cited as the etiology (or

etiologic agent until tlhe ultimate expression of a disease”
Grossman and Porth (2014). A great example

“the sequence of cellular and tissue events that take place
from the time of initial contact with an

important to define pathogenesis; not to be confused with the
term etiology. Pathogenesis refers to

allergic rhinitis, arthus reaction, contact dermatitis, and hypersensitivity
pneumonitis. To begin it is first

further classified as one of four types: type I, type II,
type III, and type IV. The topics discussed will be

In this paper I will be discussing                 the pathogenesis of several hypersensitivity
reactions which are