New study: silicone induces a strong local T-cell immune response

[Guest guest]

LM,

I wasn't sure which study you wanted me to repost, but I'll send a

few...here's one that was recent.

Patty

>

> Medline Abstract W Dolores, R Christian, N Harald, P

Hildegunde, and W Georg

Cellular and molecular composition of fibrous capsules formed

aroundsilicone breast implants with special focus on local immune

reactions.

J Autoimmun, August 1, 2004; 23(1): 81-91. Institute of

Pathophysiology, University Innsbruck, Medical School,Fritz-Pregl-

Strasse 3, 6020 Innsbruck, Austria.

During the past 30 years, much debate has centered around side

effectsof silicone breast implants. Meta-analyses rejected the

presumedrelationship between silicone breast implants and connective

tissuesdiseases but, in seeming contradiction, case reports about

connectivetissue diseases and rheumatoid symptoms continue to be

published. Weanalyzed the cellular and molecular composition of

fibrous capsulesremoved from patients at various times after surgery

for diagnosticpurposes (breast cancer relapse) or to relieve painful

constrictivefibrosis. Frozen sections of capsule tissue were

immunohistochemicallystained for

> subsets of lymphocytes, macrophages, dendritic cells,fibroblasts,

smooth muscle cells, for collagenous and non-

collagenousextracellular matrix proteins, for heat shock protein 60

(HSP60) andfor adhesion molecules. Massive deposition of fibronectin

and tenascinwas observed adjacent to the implant surface. The

capsule/siliconeimplant contact zone was consistently characterized

by a palisade-likesingle or multilayered cell accumulation

consisting of HSP60+macrophages and HSP60+ fibroblasts. Mononuclear

cell infiltratesconsisting of activated CD4+ T-cells, expressing

CD25 and CD45RO, aswell as macrophages were detected beneath the

contact zone as well asperivascularly. Importantly, many Langerhans-

cell like dendritic cells(DCs) were found with a predilection at the

frontier layer zoneabutting the silicone implant. Also, at this

site, massive expressionof ICAM-1, but not VCAM-1 or ELAM-1 emerged.

Endothelial cells of theintracapsular neovasculature were P-

Selectin+. Our results show

> thatsilicone induces a strong local T-cell immune response and

futurestudies will determine the specificity and function of theseT-

lymphocytes.