I morsi di vipera

Viper bites are rare but represent a medical emergency that should not be underestimated both in the paediatric and adult population. The clinical presentation can vary from mild symptoms limited to the venom inoculation site to serious cases with extensive tissue involvement and with systemic neurological, haematologic, renal and cardiovascular symptoms. Immediate hospitalization with clinical monitoring is required to promptly undertake the therapy with antivenom serum, when needed, in order to avoid complications related to the venom’s toxicity. In the literature there are no recent and standardised guidelines on viper bite management and treatment. The paper presents a case-series of four children brought to the Emergency Department for viper bite. The peculiarity of the reported cases is that they were all observed in the first 20 days of May 2020, immediately after the end of the lockdown for Covid-19 pandemic. This could be explained by the effect of prolonged lockdown on animal and viper re-expansion in areas with usually larger human presence. The aim of this article is to present the latest literature updates and provide clear and simple indications for the diagnosis, monitoring and therapy of paediatric viper bite to improve its management and prognosis.

Effect of the Inoculation Site of Bovine and Avian Purified Protein Derivatives (PPDs) on the Performance of the Intradermal Tuberculin Test in Goats From Tuberculosis-Free and Infected Herds

The single and comparative intradermal tuberculin (SIT and CIT) tests are used for the ante-mortem diagnosis of caprine tuberculosis (TB). The tuberculin injection site has been associated with a different performance of the test in cattle. In contrast to that required in cattle in Europe (cervical injection), it can be carried out in the scapular region in goats. Nevertheless, there are no previous data concerning the effect of the injection site on the performance of the test in goats. The aim of the present study was to evaluate the effect of two different inoculation sites (cervical and scapular) on the performance of the SIT/CIT tests. This was done by intradermally inoculating 309 goats from two infected herds and one TB-free herd with both avian and bovine PPDs in the mid-cervical and scapular regions. None of the animals from the TB-free herd had positive reactions, and the number of reactors was not significantly higher, regardless of the inoculation site, in the high and low prevalence herds. However, significantly higher increases in skin fold thickness were observed on the cervical site when compared to the scapular site after the avian and bovine PPD inoculations in the TB-free herd (p < 0.001) and after the bovine PPD injection in the high prevalence herd (p = 0.003). The presence of clinical signs was also more evident on the cervical site when using avian and bovine PPDs in the high prevalence herd (p < 0.01). In contrast, increases in higher skin fold thickness were observed on the scapular site when compared to the cervical site after the bovine and avian PPD inoculations were employed in the low prevalence herd (p < 0.01). These results suggest that the cervical injection of PPDs may improve the sensitivity of the intradermal tuberculin test in high TB prevalence caprine herds, mainly owing to the increased presence of local clinical signs and a better performance of the CIT test. Moreover, specificity was not affected when using standard interpretations, although further analyses in a great number of herds are required in order to confirm these findings.

MukB Is a Gene Necessary for Rapid Proliferation of Vibrio vulnificus in the Systemic Circulation but Not at the Local Infection Site in the Mouse Wound Infection Model

Vibrio vulnificus causes rapid septicemia in susceptible individuals who have ingested contaminated foods or have open wounds exposed to seawater contaminated with the bacteria. Despite antibiotic therapy and aggressive debridement, mortality from septicemia is high. In this study, we showed that MukB mutation (mukB::Tn) affected the proliferation of V. vulnificus in the systemic circulation but not at the inoculation site in the wound infection model. A comparison of mukB::Tn with WT and a mukB complement strain (mukB::Tn/pmukB) on the bacterial burden in the muscle at the infection site showed that spreading and proliferation of the mukB::Tn strain was similar to those of the other strains. However, the bacterial burden of mukB::Tn in the spleen was reduced compared to that of the WT strain in the wound infection model. In a competition experiment, we found a lower bacterial burden of mukB::Tn in the spleen than that of the WT strain infecting the systemic circulation. Here, we report on a gene required for the rapid proliferation of V. vulnificus only in the systemic circulation and potentially required for its survival. Our finding may provide a novel therapeutic target for V. vulnificus septicemia.

Hyaluronan is a natural and effective immunological adjuvant for protein-based vaccines

One of the main goals of vaccine research is the development of adjuvants that can enhance immune responses and are both safe and biocompatible. We explored the application of the natural polymer hyaluronan (HA) as a promising immunological adjuvant for protein-based vaccines. Chemical conjugation of HA to antigens strongly increased their immunogenicity, reduced booster requirements, and allowed antigen dose sparing. HA-based bioconjugates stimulated robust and long-lasting humoral responses without the addition of other immunostimulatory compounds and proved highly efficient when compared to other adjuvants. Due to its intrinsic biocompatibility, HA allowed the exploitation of different injection routes and did not induce inflammation at the inoculation site. This polymer promoted rapid translocation of the antigen to draining lymph nodes, thus facilitating encounters with antigen-presenting cells. Overall, HA can be regarded as an effective and biocompatible adjuvant to be exploited for the design of a wide variety of vaccines.

Modelling ‘Candidatus Liberibacter asiaticus’ movement within citrus plants

The phloem-limited ‘Candidatus Liberibacter asiaticus’ (Las) causes huanglongbing (HLB), a destructive citrus disease. Graft-inoculated potted plants were used to assess Las speed of movement in phloem in greenhouse (GH), and the impacts of temperature on plant colonization in growth chambers (GC) experiments. For assessment of Las speed, plants were inoculated at the main stem and assessed over time by qPCR or symptom at various distances from the inoculum. For colonization, the plants were inoculated in one of two opposite top branches, were maintained at 8 to 20, 18 to 30 or 24 to 38ºC daily range, and assessed by qPCR of samples taken from non-inoculated shoots. For all experiments, frequencies of Las-positive sites were submitted to ANOVA and binomial GLM and logistic regression analysis. Probabilities of detecting Las in GH plants were functions of time and distance from the inoculation site, which resulted in 2.9 and 3.8 cm day-1 average speed of movement. In GC, the temperature impacted plant colonization by Las, new shoot emission and symptom expression. After a 7-month exposure time, Las was absent in all new shoot in the cooler environment (avg 3 per plant), and present in 70% at the milder (6 shoots, severe symptoms) and 25% in the warmer (8 shoots, no visible symptoms) environments. Temperature of 25.7ºC was the optimum condition for plant colonization. This explains the higher impact and incidence of HLB during the winter months or regions of milder climates in Brazil.

Bacille Calmette-Guérin inoculation site changes and cardiac complications in patients with Kawasaki disease

ObjectiveTo investigate whether redness and crusting at the bacille Calmette-Guérin inoculation site (BCGitis), identified during acute illness owing to Kawasaki disease (KD), is an independent risk factor for development of cardiac complications.DesignRetrospective cohort study using data from the nationwide KD survey in Japan.SettingSurvey respondents included hospitals specialising in paediatrics and hospitals with ≥100 beds and a paediatric department throughout Japan.PatientsWe included 17 181 patients with KD across Japan during 2005–2006.Main outcome measuresBCGitis and cardiac complications resulting from KD.ResultsBCGitis was identified in 7549 (44%) patients with KD. Compared with patients without BCGitis, those with BCGitis were younger, more likely to be male, less likely to have recurrent status and visited a hospital and underwent initial intravenous immunoglobulin (IVIG) treatment earlier after KD onset. In the unadjusted model, patients with BCGitis were significantly less likely to have cardiac complications (crude OR 0.81, 95% CI 0.71 to 0.92). However, after including treatment factors (days of illness at initial IVIG and treatment responsiveness) in the adjusted model, the association was no longer significant (adjusted OR 0.89, 95% CI 0.77 to 1.03), indicating that BCGitis was not an independent factor associated with cardiac complication and might be confounded by treatment factors.ConclusionsBCGitis was identified in comparatively early illness stages of KD. Our findings indicated that BCGitis was not an independent factor associated with developing cardiac complications but was confounded by prompt initial IVIG administration, which might result in successful treatment and prevention of cardiac complications.

In Vivo Imaging of Local Inflammation: Monitoring LPS-Induced CD80/CD86 Upregulation by PET

Purpose The co-stimulatory molecules CD80 and CD86 are upregulated on activated antigen-presenting cells (APC). We investigated whether local APC activation, induced by subcutaneous (s.c.) inoculation of lipopolysaccharides (LPS), can be imaged by positron emission tomography (PET) with CD80/CD86-targeting 64Cu-labelled abatacept. Procedures Mice were inoculated s.c. with extracellular-matrix gel containing either LPS or vehicle (PBS). Immune cell populations were analysed by flow cytometry and marker expression by RT-qPCR. 64Cu-NODAGA-abatacept distribution was analysed using PET/CT and ex vivo biodistribution. Results The number of CD80+ and CD86+ immune cells at the LPS inoculation site significantly increased a few days after inoculation. CD68 and CD86 expression were higher at the LPS than the PBS inoculation site, and CD80 was only increased at the LPS inoculation site. CTLA-4 was highest 10 days after LPS inoculation, when CD80/CD86 decreased again. A few days after inoculation, 64Cu-NODAGA-abatacept distribution to the inoculation site was significantly higher for LPS than PBS (4.2-fold). Co-administration of unlabelled abatacept or human immunoglobulin reduced tracer uptake. The latter reduced the number of CD86+ immune cells at the LPS inoculation site. Conclusions CD80 and CD86 are upregulated in an LPS-induced local inflammation, indicating invasion of activated APCs. 64Cu-NODAGA-abatacept PET allowed following APC activation over time.

Breast cancer grade and clinical benefit in patients with advanced breast cancer treated with an engineered whole tumor cell-targeted immunotherapy alone or in combination with checkpoint inhibition.

3033 Background: SV-BR-1 is a breast cancer cell line derived from a grade II (moderately differentiated) tumor. SV-BR-1 was transfected with the CSF2 gene (encoding GM-CSF) to form SV-BR-1-GM. SV-BR-1-GM expresses HLA class I & II antigens and has functional antigen-presenting cell activity, directly stimulating CD4+ T cells in an HLA-DR restricted fashion. The SV-BR-1-GM regimen consists of low-dose cyclophosphamide (300 mg/m2) to reduce immune suppression, intradermal inoculation with irradiated SV-BR-1-GM (20x106 cells divided into 4 sites) and interferon-α2b (10,000 IU into each inoculation site ~2 & 4 days later) to boost the response. Here, we evaluate the impact of tumor grade on clinical benefit following treatment with the SV-BR-1-GM regimen. Methods: Patients with advanced breast cancer were treated with either the SV-BR-1-GM regimen alone or with the SV-BR-1-GM regimen with pembrolizumab. For the SV-BR-1-GM regimen alone, cycles were administered every 2 weeks x 3 and then monthly, while combination with pembrolizumab (200 mg IV 1-5 days following SV-BR-1-GM inoculation) administered cycles every 3 weeks. Tumor restaging was every 6-12 weeks. Results: 33 patients were enrolled. The treatment was generally safe with inoculation site pruritis, erythema and induration the most common adverse events. 23 patients had grade III (poorly differentiated) tumors, 9 had grade II tumors and one had a grade I (well differentiated) tumor. None of the patients with grade III tumors exhibited clinical benefit. 7 patients with grade I/II tumors received the SV-BR-1-GM regimen alone, 2 received the SV-BR-1-GM regimen with pembrolizumab and 1 received both regimens. As noted in the Table, 7 patients experienced clinical benefit including all 3 patients treated in combination with pembrolizumab. This included 6 patients with stable disease and one with a partial response. Conclusions: The SV-BR-1-GM regimen with or without pembrolizumab appears safe and able to induce clinical benefit even in very heavily pre-treated patients with low or intermediate grade advanced breast cancer. Clinical trial information: NCT03328026 . [Table: see text]

Herpes Simplex Viruses Whose Replication Can Be Deliberately Controlled as Candidate Vaccines

Over the last few years, we have been evaluating a novel paradigm for immunization using viruses or virus-based vectors. Safety is provided not by attenuation or inactivation of vaccine viruses, but by the introduction into the viral genomes of genetic mechanisms that allow for stringent, deliberate spatial and temporal control of virus replication. The resulting replication-competent controlled viruses (RCCVs) can be activated to undergo one or, if desired, several rounds of efficient replication at the inoculation site, but are nonreplicating in the absence of activation. Extrapolating from observations that attenuated replicating viruses are better immunogens than replication-defective or inactivated viruses, it was hypothesized that RCCVs that replicate with wild-type-like efficiency when activated will be even better immunogens. The vigorous replication of the RCCVs should also render heterologous antigens expressed from them highly immunogenic. RCCVs for administration to skin sites or mucosal membranes were constructed using a virulent wild-type HSV-1 strain as the backbone. The recombinants are activated by a localized heat treatment to the inoculation site in the presence of a small-molecule regulator (SMR). Derivatives expressing influenza virus antigens were also prepared. Immunization/challenge experiments in mouse models revealed that the activated RCCVs induced far better protective immune responses against themselves as well as against the heterologous antigens they express than unactivated RCCVs or a replication-defective HSV-1 strain. Neutralizing antibody and proliferation responses mirrored these findings. We believe that the data obtained so far warrant further research to explore the possibility of developing effective RCCV-based vaccines directed to herpetic diseases and/or diseases caused by other pathogens.