Aneta Pluta, Marzena Rola-Łuszczak, Monika Olech and Jacek Kuźmak
In this study the sequences of the long terminal repeat (LTR) of field isolates of the bovine leukaemia virus (BLV) were analysed. These isolates came from emerging cases of BLV infection in cattle from herds having BLV-free status. We found several sequence variations within regulatory motifs in the LTRs like GRE, DAS and interferon binding site. These mutations can possibly affect transcriptional activity of the virus, leading to its silencing.
Monika Olech, Marzena Rola-Łuszczak, Bożenna Kozaczyńska, Piotr Kubiś, Aneta Pluta, Anna Gil and Jacek Kuźmak
In the study, a 122 bp fragment of gag gene encoding immunodominant epitope on capsid protein of small ruminant lentiviruses (SRLVs) found in sheep was amplified by PCR and analysed by SSCP and sequencing. Out of 30 DNA samples, five showed different migration patterns, demonstrating the individual variations within gag sequences, which were confirmed afterwards by sequence analysis. In two samples nucleotide changes yielded amino acid substitutions highlighting the conservative nature of gag encoded immunoreactive epitope but also potencial insensitivity of a single-strain-based immunoassay.
Ewelina Czyżewska-Dors, Małgorzata Pomorska-Mól, Arkadiusz Dors, Aneta Pluta, Katarzyna Podgórska, Krzysztof Kwit, Ewelina Stasiak and Anna Łukomska
The study evaluated the patterns of local innate immune response in bronchoalveolar lavage fluid (BALF) cells of pigs infected with porcine reproductive and respiratory syndrome virus (PRRSV) alone or co-infected with swine influenza virus (SIV).
Material and Methods
The study was performed on 26 seven-week-old pigs in three groups: PRRSV-infected (n = 11), PRRSV and SIV-infected (n = 11), and control (n = 4). BALF was collected post euthanasia at 2 and 4 dpi (three piglets per inoculated group) and at 21 dpi (all remaining pigs). Expression of IFN-α, IFN-γ, IL-1β, IL-6, IL-8, and IL-10 mRNA was quantified in BALF cells. PRRSV RNA was quantified in BALF samples using a commercial real-time RT-PCR kit.
The three cytokines IFN-α, IFN-γ, and IL-1β presented significant expression changes in all experimental pigs. In PRRSV-infected animals IL-8 also did, but in co-infected subjects IL-6 and IL-10 were the additional upregulated cytokines. The highest number of differentially expressed genes was observed at 4 dpi, and significant differences in cytokine gene expression did not occur between the experimental groups at any other time point. The mean PRRSV load in the BALF of PRRSV-infected pigs was higher than that of co-infected pigs at each time point, having statistical significance only at 4 dpi.
The results of the study indicate that infection with PRRSV alone as well as with SIV interferes with innate and adaptive immune response in the infected host. They also showed that co-infection demonstrates additive effects on IL-6 and IL-10 mRNA expression levels.