Preclinical safety and tolerability of a repeatedly administered human leishmaniasis DNA vaccine

Riede, O; Seifert, K; Oswald, D; Endmann, A; Hock, C; Winkler, A; Salguero, F J; Schroff, M; Croft, S L; Juhls, C

To assess the induction of an immune response against dsDNA a radioimmunoassay was performed at IBL International GmbH (Hamburg, Germany) using a kit for detection of anti-dsDNA antibodies (IBL International). In brief, 25 μl of serum sample was mixed with 150 μl of 125 I-labeled dsDNA tracer and incubated at 37°C for 60 min. Subsequently, 1 ml of cold ammonium sulfate solution was added to the sample followed by vortexing. Tubes were centrifuged (15 min at 1500 g) and supernatant was removed. Radioactivity was counted using a gamma counter and the dsDNA binding capacity was calculated according to a standard curve. under specific pathogen-free conditions in individually ventilated cages and exposed to 12 h light-12 h dark cycles. Standard rodent diet (RM No 1 Expanded) and de-ionized water were supplied ad libitum. L. donovani (strain MHOM/ET/67/HU3) was maintained in Rag-1 (B6) KO mice and amastigotes harvested from spleens of infected animals 440 days after infection.