TY - JOUR
T1 - Potentiation of complement regulator factor H protects human endothelial cells from complement attack in aHUS sera
AU - Pouw, Richard B.
AU - Brouwer, Mieke C.
AU - de Gast, Marlon
AU - van Beek, Anna E.
AU - van den Heuvel, Lambertus P.
AU - Schmidt, Christoph Q.
AU - van der Ende, Arie
AU - Sánchez-Corral, Pilar
AU - Kuijpers, Taco W.
AU - Wouters, Diana
PY - 2019/2/26
Y1 - 2019/2/26
N2 - Mutations in the gene encoding for complement regulator factor H (FH) severely disrupt its normal function to protect human cells from unwanted complement activation, resulting in diseases such as atypical hemolytic uremic syndrome (aHUS). aHUS presents with severe hemolytic anemia, thrombocytopenia, and renal disease, leading to end-stage renal failure. Treatment of severe complement-mediated disease, such as aHUS, by inhibiting the terminal complement pathway, has proven to be successful but at the same time fails to preserve the protective role of complement against pathogens. To improve complement regulation on human cells without interfering with antimicrobial activity, we identified an anti-FH monoclonal antibody (mAb) that induced increased FH-mediated protection of primary human endothelial cells from complement, while preserving the complement-mediated killing of bacteria. Moreover, this FH-activating mAb restored complement regulation in sera from aHUS patients carrying various heterozygous mutations in FH known to impair FH function and dysregulate complement activation. Our data suggest that FH normally circulates in a less active conformation and can become more active, allowing enhanced complement regulation on human cells. Antibody-mediated potentiation of FH may serve as a highly effective approach to inhibit unwanted complement activation on human cells in a wide range of hematological diseases while preserving the protective role of complement against pathogens.
AB - Mutations in the gene encoding for complement regulator factor H (FH) severely disrupt its normal function to protect human cells from unwanted complement activation, resulting in diseases such as atypical hemolytic uremic syndrome (aHUS). aHUS presents with severe hemolytic anemia, thrombocytopenia, and renal disease, leading to end-stage renal failure. Treatment of severe complement-mediated disease, such as aHUS, by inhibiting the terminal complement pathway, has proven to be successful but at the same time fails to preserve the protective role of complement against pathogens. To improve complement regulation on human cells without interfering with antimicrobial activity, we identified an anti-FH monoclonal antibody (mAb) that induced increased FH-mediated protection of primary human endothelial cells from complement, while preserving the complement-mediated killing of bacteria. Moreover, this FH-activating mAb restored complement regulation in sera from aHUS patients carrying various heterozygous mutations in FH known to impair FH function and dysregulate complement activation. Our data suggest that FH normally circulates in a less active conformation and can become more active, allowing enhanced complement regulation on human cells. Antibody-mediated potentiation of FH may serve as a highly effective approach to inhibit unwanted complement activation on human cells in a wide range of hematological diseases while preserving the protective role of complement against pathogens.
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85062177314&origin=inward
UR - https://www.ncbi.nlm.nih.gov/pubmed/30804016
U2 - https://doi.org/10.1182/bloodadvances.2018025692
DO - https://doi.org/10.1182/bloodadvances.2018025692
M3 - Article
C2 - 30804016
SN - 2473-9529
VL - 3
SP - 621
EP - 632
JO - Blood
JF - Blood
IS - 4
ER -