Uncoordinated production of Laminin-5 chains in airways epithelium of allergic asthmatics.
BACKGROUND
Laminins are a group of proteins largely responsible for the anchorage of cells to basement membranes. We hypothesized that altered Laminin chain production in the bronchial mucosa might explain the phenomenon of epithelial cell shedding in asthma. The aim was to characterize the presence of Laminin chains in the SEBM and epithelium in allergic and non-allergic asthmatics.


METHODS
Biopsies were taken from the bronchi of 11 patients with allergic and 9 patients with non-allergic asthma and from 7 controls and stained with antibodies against the Laminin (ln) chains alpha1-alpha5, beta1-beta2 and gamma1-gamma2.


RESULTS
Lns-2,-5 and -10 were the main Laminins of SEBM. The layer of ln-10 was thicker in the two asthmatic groups while an increased thickness of lns-2 and -5 was only seen in allergic asthmatics. The ln gamma2-chain, which is only found in ln 5, was exclusively expressed in epithelial cells in association with epithelial injury and in the columnar epithelium of allergic asthmatics.


CONCLUSIONS
The uncoordinated production of chains of ln-5 in allergic asthma could have a bearing on the poor epithelial cell anchorage in these patients.
Amin
Kawa
K
Department of Medical Sciences, Clinical Chemistry, Uppsala University, Uppsala, Sweden. kawa.amin@medsci.uu.se
Janson
Christer
C
Sevéus
Lahja
L
Miyazaki
Kaoru
K
Virtanen
Ismo
I
Venge
Per
P
D000328:Adult; D001249:Asthma / Q000150:complications / Q000378:metabolism* / Q000473:pathology*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012130:Respiratory Hypersensitivity / Q000150:complications / Q000378:metabolism* / Q000473:pathology*; D020545:Respiratory Mucosa / Q000378:metabolism* / Q000473:pathology*; D014018:Tissue Distribution; D000097794:Kalinin
D015815:Cell Adhesion Molecules; D000097794:Kalinin