Abstract
The lectin pathway of the complement system can activate the coagulation system in
vitro, but the role of the lectin pathway in haemostatic activation and thrombosis
in vivo is not clear. We performed a systematic review of the existing literature
on associations between the lectin pathway and arterial and venous thrombosis, in
accordance with the Assessing the Methodological Quality of Systematic Reviews guidelines.
PubMed and Embase were searched from January 1990 to March 2017. We included original
studies on human study populations investigating associations between the lectin pathway
(protein serum levels, genotype or gene expression) and thrombotic conditions or laboratory
coagulation markers. Exclusion criteria were case studies including fewer than five
cases, conference abstracts or any other language than English. In total, 43 studies
were included which investigated associations between the lectin pathway and cardiovascular
thrombotic events (CVEs) (n = 22), ischaemic stroke (n = 9), CVE and stroke (n = 1) and other conditions (systemic lupus erythematosus [n = 6], sepsis-related coagulopathy [n = 3], pulmonary embolism [n = 1], asparaginase treatment [n = 1]). Studies on the lectin pathway and CVE risk reported discrepant results, as
both high and low mannose-binding lectin (MBL) serum levels were found to correlate
with increased CVE risk. In ischaemic stroke patients, occurrence of stroke as well
as increased stroke severity and poor outcome were consistently associated with high
serum MBL. For other thromboembolic conditions, only few studies were identified.
In conclusion, lectin pathway activation may negatively influence outcome after ischaemic
stroke and possibly contribute to CVE risk. Further research is warranted to elucidate
the role of the lectin pathway in other thrombotic conditions.
Keywords
lectin pathway - complement proteins - mannose-binding lectin - thromboembolism -
blood coagulation
