TY - JOUR
T1 - Role of mannose-binding lectin in the innate defense against Candida albicans
T2 - Enhancement of complement activation, but lack of opsonic function, in phagocytosis by human dendritic cells
AU - Ip, Wai Kee
AU - Lau, Yo Lung
N1 - Funding Information:
Financial support: Research Grants Council of Hong Kong Special Administrative Region, China (grant RGC#HKU-7260/01M); Committee on Research and Conference Grants and the Outstanding Researcher Award (to Y.L.L.); University of Hong Kong.
PY - 2004/8/1
Y1 - 2004/8/1
N2 - Mannose-binding lectin (MBL) is a serum collectin believed to be of importance in innate immunity. We have investigated the role of MBL in the first-line defense against Candida albicans, an opportunistic fungal pathogen. MBL bound C. albicans via its lectin domain, resulting in agglutination of the organisms upon their outgrowth of hyphae. In a human in vitro MBL system, deposition of C4 fragments on C. albicans was increased when exogenous MBL was added to serum samples from MBL-deficient individuals. Similar enhancement of deposition of iC3b also was observed. MBL and enhanced opsonic C3 fragments mediated by MBL did not facilitate opsonophagocytosis of the organisms by monocyte-derived dendritic cells (DCs). However, MBL was found to inhibit the growth of C. albicans independently of complement activation, although, with complement activation, further inhibition was observed. We concluded that MBL plays an important role in the first-line defense against C. albicans without the need for opsonophagocytosis by DCs, in which a direct interaction of MBL with C. albicans results in agglutination and accelerated complement activation via the lectin pathway, leading to inhibition of growth.
AB - Mannose-binding lectin (MBL) is a serum collectin believed to be of importance in innate immunity. We have investigated the role of MBL in the first-line defense against Candida albicans, an opportunistic fungal pathogen. MBL bound C. albicans via its lectin domain, resulting in agglutination of the organisms upon their outgrowth of hyphae. In a human in vitro MBL system, deposition of C4 fragments on C. albicans was increased when exogenous MBL was added to serum samples from MBL-deficient individuals. Similar enhancement of deposition of iC3b also was observed. MBL and enhanced opsonic C3 fragments mediated by MBL did not facilitate opsonophagocytosis of the organisms by monocyte-derived dendritic cells (DCs). However, MBL was found to inhibit the growth of C. albicans independently of complement activation, although, with complement activation, further inhibition was observed. We concluded that MBL plays an important role in the first-line defense against C. albicans without the need for opsonophagocytosis by DCs, in which a direct interaction of MBL with C. albicans results in agglutination and accelerated complement activation via the lectin pathway, leading to inhibition of growth.
UR - http://www.scopus.com/inward/record.url?scp=3242748243&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=3242748243&partnerID=8YFLogxK
U2 - 10.1086/422397
DO - 10.1086/422397
M3 - Article
C2 - 15243942
AN - SCOPUS:3242748243
VL - 190
SP - 632
EP - 640
JO - Journal of Infectious Diseases
JF - Journal of Infectious Diseases
SN - 0022-1899
IS - 3
ER -