Thiolated recombinant human tumor necrosis factor-alpha protects against Plasmodium berghei K173-induced experimental cerebral malaria in mice.
The introduction of reactive thiol groups in recombinant human tumor necrosis factor (TNF) alpha (rhTNF-alpha) by the reagent succinimidyl-S-acetylthioacetate resulted in the formation of a chemically stabilized rhTNF-alpha trimer (rhTNFalpha-AT; as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis). rhTNFalpha-AT showed a substantially enhanced protective efficacy against the development of experimental murine cerebral malaria (ECM) after intravenous injection compared to the protective efficacy of nonmodified rhTNF-alpha. Administration of thiolated rhTNF-alpha with protected thiol groups (rhTNFalpha-ATA; no stabilized trimers in vitro) exhibited the same protective efficacy against ECM, while in vitro bioactivity was reduced. Parasitemia was significantly suppressed in rhTNF-treated mice that were protected against ECM but not in treated mice that developed ECM. Protection against ECM was not related to increased concentrations in plasma of soluble TNF receptor 1 and 2 directly after injection or at the moment of development of ECM in nontreated mice. The results indicate that thiolation of rhTNF-alpha leads to the formation of stable trimers with increased potential in vivo.
Postma
N S
NS
Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3508 TB Utrecht, The Netherlands.
Hermsen
R C
RC
Crommelin
D J
DJ
Eling
W M
WM
Zuidema
J
J
D000818:Animals; D006801:Humans; D007275:Injections, Intravenous; D016779:Malaria, Cerebral / Q000097:blood / Q000517:prevention & control*; D051379:Mice; D010962:Plasmodium berghei; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000737:chemistry; D013388:Succinimides; D013439:Sulfhydryl Reagents; D013440:Sulfides; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage* / Q000737:chemistry
D018124:Receptors, Tumor Necrosis Factor; D011994:Recombinant Proteins; D013388:Succinimides; D013439:Sulfhydryl Reagents; D013440:Sulfides; D014409:Tumor Necrosis Factor-alpha; C039011:N-hydroxysuccinimide S-acetylthioacetate