TY  - JOUR
A1  - Carmona Arana, José Antonio
A1  - Seher, Axel
A1  - Neumann, Manfred
A1  - Lang, Isabell
A1  - Siegmund, Daniela
A1  - Wajant, Harald
T1  - TNF Receptor-Associated Factor 1 is a Major Target of Soluble TWEAK
JF  - Frontiers in Immunology
N2  - Soluble tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK), in contrast to membrane TWEAK and TNF, is only a weak activator of the classical NFκB pathway. We observed that soluble TWEAK was regularly more potent than TNF with respect to the induction of TNF receptor-associated factor 1 (TRAF1), a NFκB-controlled signaling protein involved in the regulation of inflammatory signaling pathways. TNF-induced TRAF1 expression was efficiently blocked by inhibition of the classical NFκB pathway using the IKK2 inhibitor, TPCA1. In contrast, in some cell lines, TWEAK-induced TRAF1 production was only partly inhibited by TPCA1. The NEDD8-activating enzyme inhibitor MLN4924, however, which inhibits classical and alternative NFκB signaling, blocked TNF- and TWEAK-induced TRAF1 expression. This suggests that TRAF1 induction by soluble TWEAK is based on the cooperative activity of the two NFκB signaling pathways. We have previously shown that oligomerization of soluble TWEAK results in ligand complexes with membrane TWEAK-like activity. Oligomerization of soluble TWEAK showed no effect on the dose response of TRAF1 induction, but potentiated the ability of soluble TWEAK to trigger production of the classical NFκB-regulated cytokine IL8. Transfectants expressing soluble TWEAK and membrane TWEAK showed similar induction of TRAF1 while only the membrane TWEAK expressing cells robustly stimulated IL8 production. These data indicate that soluble TWEAK may efficiently induce a distinct subset of the membrane TWEAK-targeted genes and argue again for a crucial role of classical NFκB pathway-independent signaling in TWEAK-induced TRAF1 expression. Other TWEAK targets, which can be equally well induced by soluble and membrane TWEAK, remain to be identified and the relevance of the ability of soluble TWEAK to induce such a distinct subset of membrane TWEAK-targeted genes for TWEAK biology will have to be clarified in future studies.
KW  - RAF1
KW  - TWEAK
KW  - TNF
KW  - NFκB
KW  - CD40
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-120620
SN  - 1664-3224
VL  - 5
IS  - 63
ER  - 
TY  - JOUR
A1  - Brunekreeft, Kim L.
A1  - Strohm, Corinna
A1  - Gooden, Marloes J.
A1  - Rybczynska, Anna A.
A1  - Nijman, Hans W.
A1  - Grigoleit, Götz U.
A1  - Helfrich, Wijnand
A1  - Bremer, Edwin
A1  - Siegmund, Daniela
A1  - Wajant, Harald
A1  - de Bruyn, Marco
T1  - Targeted delivery of CD40L promotes restricted activation of antigen-presenting cells and induction of cancer cell death
JF  - Molecular Cancer
N2  - Background: Stimulation of CD40 can augment anti-cancer T cell immune responses by triggering effective activation and maturation of antigen-presenting cells (APCs). Although CD40 agonists have clinical activity in humans, the associated systemic activation of the immune system triggers dose-limiting side-effects. 
Methods: To increase the tumor selectivity of CD40 agonist-based therapies, we developed an approach in which soluble trimeric CD40L (sCD40L) is genetically fused to tumor targeting antibody fragments, yielding scFv: CD40L fusion proteins. We hypothesized that scFv: CD40L fusion proteins would have reduced CD40 agonist activity similar to sCD40L but will be converted to a highly agonistic membrane CD40L-like form of CD40L upon anchoring to cell surface exposed antigen via the scFv domain. 
Results: Targeted delivery of CD40L to the carcinoma marker EpCAM on carcinoma cells induced dose-dependent paracrine maturation of DCs similar to 20-fold more effective than a non-targeted control scFv: CD40L fusion protein. Similarly, targeted delivery of CD40L to the B cell leukemia marker CD20 induced effective paracrine maturation of DCs. Of note, the CD20-selective delivery of CD40L also triggered loss of cell viability in certain B cell leukemic cell lines as a result of CD20-induced apoptosis. 
Conclusions: Targeted delivery of CD40L to cancer cells is a promising strategy that may help to trigger cancer-localized activation of CD40 and can be modified to exert additional anti-cancer activity via the targeting domain.
KW  - CD20
KW  - EpCAM
KW  - CD40L
KW  - ScFv
KW  - targeting
KW  - dendritic cells
KW  - T-cells
KW  - monoclonal-antibodies
KW  - immune modulation
KW  - autologous tumor
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-116682
SN  - 1476-4598
VL  - 13
IS  - 85
ER  -