Interferon Induction by HIV-1-Infected Cells: A Possible Role of Sulfatides or Related Glycolipids

AbstractWe have investigated the mechanism of interferon (IFN) induction in peripheral blood mononuclear cells by HIV-1(IIIB)-infected H9 cells or by recombinant gp120. A monoclonal antibody specific for the galactosylsphingosinyl moiety in galactocerebrosides and sulfatides inhibited IFN induction in a dose-dependent manner. Furthermore, exogenous sulfatides inhibited with an ID50of approximately 1 μM,whereas galactocerebrosides were not inhibitory at 40 times higher concentrations. These studies suggest that sulfate containing galactolipids such as sulfatides on responder cells may be part of the gp120–membrane complex that initiates the induction of IFN. A partial homology of an epitope on the V3 loop of gp120 with a previously suggested binding domain for sulfated glycoconjugates supports this conclusion

Orthopoxvirus Seroprevalence in Cats and Veterinary Personnel in North-Eastern Italy in 2011

Orthopoxviruses (OPV) are emerging zoonotic pathogens, and an increasing number of human infections is currently reported in Europe and in other continents, warranting heightened attention on this topic. Following two OPV infections reported in veterinarians scratched by sick cats in 2005 and 2007 in North-Eastern-Italy, involving a previously undescribed OPV, a similar strain was isolated by a sick cat from the same territory in 2011, i.e., 6 years later, raising attention on OPV circulation in this region. A surveillance program was launched to assess the OPV seroprevalence among the veterinarians working in local veterinary clinics and in the local wild and domestic cat population; seroprevalence was 33.3% in veterinarians and 19.5% in cats. Seroprevalence in cats was unevenly distributed, peaking at 40% in the area where OPV-infected cats had been observed

Performance of rapid tests in the management of dengue fever imported cases in Lazio, Italy 2014-2019

Abstract Background In Italy, dengue virus is the most frequent agent of imported viral infections. The use of rapid diagnostic tests (RDTs) may be of help as a preliminary user-friendly quick assay to facilitate dengue diagnosis, as ordinary laboratory diagnosis of dengue fever may require special efforts in terms of tools availability, interpretation of results, and skilled personnel. The performance of RDTs, however, may vary according to different epidemiological and laboratory background. Methods We reviewed five years of laboratory records of two dengue RDT results (Colorimetric SD-Bioline Dengue-Duo-RDT and Fluorimetric SD-Biosensor-STANDARD-F-Dengue-RDT), able to detect viral NS1 antigen and specific IgM and IgG. Diagnostic parameters were calculated using as reference the results of molecular (RT-PCR) and serological (immunofluorescence, IFA) tests. Overall performance, calculated considering the final case definition, was included in the accuracy assessment of RDTs. Results The combined use of NS1 and IgM/IgG RDT for the detection of acute dengue cases resulted in an overall sensitivity and specificity of 87.2% and 97.9% for Colorimetric RDT, 96.2% and 96.2% for Fluorimetric RDT. NS1 was the most reliable marker of acute infection, while IgM resulted falsely positive in nine samples, including sera derived from 2 Zika and 4 non-arbovirus infected patients. Conclusions The inclusion of RDT in the diagnostic algorithm is of undeniable help in the prompt management and surveillance of dengue infection in non-endemic areas. Confirmatory tests are, however, necessary to rule in or rule out dengue fever diagnosis

Subjects who developed SARS-CoV-2 specific IgM after vaccination show a longer humoral immunity and a lower frequency of infection

Background: We have previously shown that eliciting SARS-CoV-2-specific IgM after vaccination is associated with higher levels of SARS-CoV-2 neutralizing IgG. This study aims to assess whether IgM development is also associated with longer-lasting immunity. Methods: We analysed anti-SARS-CoV-2 spike protein IgG and IgM (IgG-S, IgM-S), and anti-nucleocapsid IgG (IgG-N) in 1872 vaccinees at different time points: before the first dose (D1; w0), before the second dose (D2; w3) at three (w6) and 23 weeks (w29) after D2; moreover, 109 subjects were further tested at the booster dose (D3, w44), at 3 weeks (w47) and 6 months (w70) after D3. Two-level linear regression models were used to evaluate the differences in IgG-S levels. Findings: In subjects who had no evidence of a previous infection at D1 (non-infected, NI), IgM-S development after D1 and D2 was associated with higher IgG-S levels at short (w6, p < 0.0001) and long (w29, p < 0.001) follow-up. Similar IgG-S levels were observed after D3. The majority (28/33, 85%) of the NI subjects who had developed IgM-S in response to vaccination did not experience infection. Interpretation: The development of anti-SARS-CoV-2 IgM-S following D1 and D2 is associated with higher IgG-S levels. Most individuals who developed IgM-S never became infected, suggesting that IgM elicitation may be associated with a lower risk of infection. Funding: "Fondi Ricerca Corrente" and "Progetto Ricerca Finalizzata" COVID-2020 (Italian Ministry of Health); FUR 2020 Department of Excellence 2018-2022 (MIUR, Italy); the Brain Research Foundation Verona

Full-length genome sequence of a dengue serotype 1 virus isolate from a traveler returning from Democratic Republic of Congo to Italy, July 2019.

Abstract We report the full-genome sequence of a Dengue serotype-1 virus (DENV-1) isolated from a traveller returning in July 2019 to Italy from Democratic Republic of Congo (DRC), which is currently affected by Ebola and measles outbreaks. The sequence shows high similarity with two 2013 strains isolated in Angola and China

Transgenic chloroplasts are efficient sites for high-yield production of the vaccinia virus envelope protein A27L in plant cells.

Orthopoxviruses (OPVs) have recently received increasing attention because of their potential use in bioterrorism and the occurrence of zoonotic OPV outbreaks, highlighting the need for the development of safe and cost-effective vaccines against smallpox and related viruses. In this respect, the production of subunit protein-based vaccines in transgenic plants is an attractive approach. For this purpose, the A27L immunogenic protein of vaccinia virus was expressed in tobacco using stable transformation of the nuclear or plastid genome. The vaccinia virus protein was expressed in the stroma of transplastomic plants in soluble form and accumulated to about 18% of total soluble protein (equivalent to approximately 1.7 mg/g fresh weight). This level of A27L accumulation was 500-fold higher than that in nuclear transformed plants, and did not decline during leaf development. Transplastomic plants showed a partial reduction in growth and were chlorotic, but reached maturity and set fertile seeds. Analysis by immunofluorescence microscopy indicated altered chlorophyll distribution. Chloroplast-synthesized A27L formed oligomers, suggesting correct folding and quaternary structure, and was recognized by serum from a patient recently infected by a zoonotic OPV. Taken together, these results demonstrate that chloroplasts are an attractive production vehicle for the expression of OPV subunit vaccines