Deposition of Amyloid/ Amyloid deposition/ Amyloidosis

Amyloidosis means various fibrillary protein depositions in the interstitial tissue in various pathological conditions.
So different Amyloids have different characteristics.
But all have following common characteristics.
With iodine brown colour (color) is produced
Characteristic staining pattern
On electron microscope amyloid appear non branching fibrils
On X-ray diffraction Amyloid exhibit a pleaded beta structure

Chemically Amyloid has two major classes

Amyloid of immunoglobulin origin
Amyloid of other origin

Amyloid of immunoglobulin origin
This is composed of light chains of immunoglobulin molecules. This form is mainly produced by neoplastic plasma cells and B cell lymphomas

Amyloid of other origin

These are composed of,
Serum Amyloid associated protein
Prealbumin
Other peptide fragments



Systemic Amyloidosis
Primary pattern of distribution
Secondary pattern of distribution
Localized Amyloidosis
Amyloid in neoplasms
Free radicals and Amyloid / Amyloidosis


Effects of Amyloid deposition

Amyloid deposited in the interstitial tissue mainly in the basement membrane of the small blood vessels. This also occurs in peripheral nerves. Due to Amyloid deposition flexibility of these tissues are lost. So blood vessels can not contract and tend to bleed more after an injury.

Other relevant areas

Heredofamilial Amyloidosis
Senile Amyloidosis
Amyloid theory of ageing
Ageing and Amyloidosis
Modern theory of ageing