Active screening of COVID-19-associated pulmonary aspergillosis with serum beta-glucan and endotracheal aspirates galactomannan and fungal culture.

BACKGROUND: Since February 2021 active screening of COVID-19-associated pulmonary aspergillosis (CAPA) has been implemented in our institution. OBJECTIVES: To evaluate CAPA incidence in our centre and evaluate performance of our screening protocol. METHODS: We screened once per week, collecting endotracheal aspirates for fungal culture and galactomannan (GM) and serum for 1,3-ß-D-glucan (BG). In case of positivity (GM more than 4.5, platelia assay, and/or BG >7 pg/ml, wako and/or positive fungal culture), second-level investigations were performed to pursue CAPA diagnosis according to ECMM/ISHAM criteria: bronchoalveolar lavage (BAL) fungal culture and GM, chest computed tomography (CT), serum GM. RESULTS: A total of 102 patients were screened (median age 64 years, range 39-79; 28 (27.4%) females). Twenty-two patients were diagnosed with CAPA (21%). 12 patients were positive for serum BG, 17 patients were positive for endotracheal aspirates GM and 27 patients were positive for endotracheal aspirates fungal culture. Thirty-two BALs were performed, and 26 patients underwent CT chest. Following the second level investigations 61% of the patients with positive screening tests were diagnosed with CAPA. Serum BG above 20 pg/ml or positive serum GM were always associated with typical CT chest signs of aspergillosis. Compared with 1 single positive test, having 2 positive screening test was significantly more associated with CAPA diagnosis (p = .0004). CONCLUSIONS: Active CAPA screening with serum 1,3-ß-D-glucan and endotracheal aspirates galactomannan and fungal cultures and consequent second level investigations led to high number of CAPA diagnosis. Combining more positive fungal biomarkers was more predictive of CAPA diagnosis.

Intravenous methylprednisolone pulses in hospitalised patients with severe COVID-19 pneumonia: a double-blind, randomised, placebo-controlled trial.

RATIONALE: Pulse glucocorticoid therapy is used in hyperinflammation related to coronavirus disease 2019 (COVID-19). We evaluated the efficacy and safety of pulse intravenous methylprednisolone in addition to standard treatment in COVID-19 pneumonia. METHODS: In this multicentre, randomised, double-blind, placebo-controlled trial, 304 hospitalised patients with COVID-19 pneumonia were randomised to receive 1 g of methylprednisolone intravenously for three consecutive days or placebo in addition to standard dexamethasone. The primary outcome was the duration of patient hospitalisation, calculated as the time interval between randomisation and hospital discharge without the need for supplementary oxygen. The key secondary outcomes were survival free from invasive ventilation with orotracheal intubation and overall survival. RESULTS: Overall, 112 (75.4%) out of 151 patients in the pulse methylprednisolone arm and 111 (75.2%) of 150 in the placebo arm were discharged from hospital without oxygen within 30 days from randomisation. Median time to discharge was similar in both groups (15 days, 95% CI 13.0-17.0 days and 16 days, 95% CI 13.8-18.2 days, respectively; hazard ratio (HR) 0.92, 95% CI 0.71-1.20; p=0.528). No significant differences between pulse methylprednisolone and placebo arms were observed in terms of admission to intensive care unit with orotracheal intubation or death (20.0% versus 16.1%; HR 1.26, 95% CI 0.74-2.16; p=0.176) or overall mortality (10.0% versus 12.2%; HR 0.83, 95% CI 0.42-1.64; p=0.584). Serious adverse events occurred with similar frequency in the two groups. CONCLUSIONS: Methylprenisolone pulse therapy added to dexamethasone was not of benefit in patients with COVID-19 pneumonia.

Early versus delayed antiretroviral therapy based on genotypic resistance test: Results from a large retrospective cohort study.

Rapid start of antiretroviral therapy (ART) pending genotypic resistance test (GRT) has been recently proposed, but the effectiveness of this strategy is still debated. The rate of virological success (VS), defined as HIV-RNA < 50 copies/ml, with and without GRT was compared in drug-naïve individuals enrolled in the Italian ARCA cohort who started ART between 2015 and 2018. 521 individuals started ART: 397 without GRT (pre-GRT group) and 124 following GRT (post-GRT group). Overall, 398 (76%) were males and 30 (6%) were diagnosed with AIDS. In the pre-GRT group, baseline CD4+ cell counts were lower (p < 0.001), and viral load was higher (p < 0.001) than in the post-GRT group. The estimated probability of VS in pre-GRT versus post-GRT group was 72.54% (CI95 : 67.78-76.60) versus 66.94% (CI95 : 57.53-74.26) at Week 24 and 92.40% (CI95 : 89.26-94.62) versus 92.92% (CI95 : 86.35-96.33) at Week 48, respectively (p = 0.434). At Week 48, VS was less frequent among individuals with baseline CD4+ cell counts <200 versus >500 (90.33% vs. 97.33%), log viral load <5.00 versus >5.70 log10 cps/ml (97.17% vs 78.16%; p < 0.001), and those treated with protease inhibitors or non-nucleoside reverse transcriptase inhibitors versus those treated with integrase strand transfer inhibitors (p < 0.001). The rate of VS does not seem to be affected by an early ART initiation pending GRT results, but it could be influenced by the composition of the ART regimen, as well as immuno-virological parameters.

High-dose glucocorticoids pulse-therapy for beta-coronaviridae pneumonia: a systematic literature review and case-series of Coronavirus disease-2019.

OBJECTIVES: The results of the RECOVERY trial identified dexamethasone as the first pharmacological therapy that reduces mortality in patients with COVID-19. The aim of this paper is to conduct a systematic literature review on safety and efficacy of pulse glucocorticoid therapy for Severe Acute Respiratory Syndrome (SARS)-CoronaVirus (CoV), Middle East Respiratory Syndrome (MERS)-CoV or SARS-CoV-2 infections and describe a case-series of COVID-19 patients treated with off-label pulse doses of methylprednisolone. METHODS: We performed a systematic literature review on safety and efficacy of pulse therapy for betacoronaviridae infections as described in the protocol registered on PROSPERO (CRD42020190183). All consecutive patients admitted to Arcispedale Santa Maria Nuova di Reggio Emilia or Guastalla Hospital with COVID-19 between March 1st and April 30th, 2020 and treated with methylprednisolone 1 gram/day for at least three days were included in the case series. A retrospective review of available computed tomography (CT) scan and chest x-ray was performed independently by two radiologists blinded to clinical data, and discordances were resolved by consensus. RESULTS: Twenty papers were included for SARS, but only two were comparative and were included in the primary endpoint analysis. Likewise, eleven papers were included for COVID-19, four of which were comparative and were considered for the primary outcome analysis. Included studies for both SARS and COVID-19 are mostly retrospective and highly heterogeneous, with lethality ranging from 0% to 100% and ICU admission rate ranging from 9% to 100%. Fourteen patients were included in our case series, 7 males and 7 females. CONCLUSIONS: No randomised controlled trial is available yet for corticosteroids pulse-therapy defined as at least ≥500mg/day methylprednisolone in patients with emerging coronavirus pneumonia. Lethality among our cohort is high (4/14), but this finding should be interpreted with caution due to the fact that in our setting pulse-steroids were used in patients not eligible for other treatments because of comorbidities or as rescue therapy. The incidence of steroid-related adverse events seems low in our cohort. The quality of the evidence on glucocorticoid pulse-therapy in SARS, MERS and COVID-19 is poor. Randomised controlled trials are greatly needed.

A Trivalent Enzymatic System for Uricolytic Therapy of HPRT Deficiency and Lesch-Nyhan Disease.

PURPOSE: Because of the evolutionary loss of the uricolytic pathway, humans accumulate poorly soluble urate as the final product of purine catabolism. Restoration of uricolysis through enzyme therapy is a promising treatment for severe hyperuricemia caused by deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT). To this end, we studied the effect of PEG conjugation on the activity and stability of the enzymatic complement required for conversion of urate into the more soluble (S)-allantoin. METHODS: We produced in recombinant form three zebrafish enzymes required in the uricolytic pathway. We carried out a systematic study of the effect of PEGylation on the function and stability of the three enzymes by varying PEG length, chemistry and degree of conjugation. We assayed in vitro the uricolytic activity of the PEGylated enzymatic triad. RESULTS: We defined conditions that allow PEGylated enzymes to retain native-like enzymatic activity even after lyophilization or prolonged storage. A combination of the three enzymes in an appropriate ratio allowed efficient conversion of urate to (S)-allantoin with no accumulation of intermediate metabolites. CONCLUSIONS: Pharmaceutical restoration of the uricolytic pathway is a viable approach for the treatment of severe hyperuricemia.

Autoproteolytic Activation of a Symbiosis-regulated Truffle Phospholipase A2.

Fungal phospholipases are members of the fungal/bacterial group XIV secreted phospholipases A(2) (sPLA(2)s). TbSP1, the sPLA(2) primarily addressed in this study, is up-regulated by nutrient deprivation and is preferentially expressed in the symbiotic stage of the ectomycorrhizal fungus Tuber borchii. A peculiar feature of this phospholipase and of its ortholog from the black truffle Tuber melanosporum is the presence of a 54-amino acid sequence of unknown functional significance, interposed between the signal peptide and the start of the conserved catalytic core of the enzyme. X-ray diffraction analysis of a recombinant TbSP1 form corresponding to the secreted protein previously identified in T. borchii mycelia revealed a structure comprising the five α-helices that form the phospholipase catalytic module but lacking the N-terminal 54 amino acids. This finding led to a series of functional studies that showed that TbSP1, as well as its T. melanosporum ortholog, is a self-processing pro-phospholipase A(2), whose phospholipase activity increases up to 80-fold following autoproteolytic removal of the N-terminal peptide. Proteolytic cleavage occurs within a serine-rich, intrinsically flexible region of TbSP1, does not involve the phospholipase active site, and proceeds via an intermolecular mechanism. Autoproteolytic activation, which also takes place at the surface of nutrient-starved, sPLA(2) overexpressing hyphae, may strengthen and further control the effects of phospholipase up-regulation in response to nutrient deprivation, also in the context of symbiosis establishment and mycorrhiza formation.

Appropriateness of antibiotic prescribing in paediatrics: retrospective controlled study assessing a multifaceted intervention in Northern Italy in a 7-year period.

BACKGROUND: Academic detailing, audit and feedback, and peer comparison have been advocated as effective ways to promote appropriateness of prescribing and antimicrobial stewardship (AMS). This study explored the effectiveness of a multifaceted intervention aimed at supporting the appropriateness of antibiotic prescribing in paediatrics. METHODS: Over the course of 7 years, all 89 paediatricians of the Local Health Authority (LHA) of Reggio Emilia (530 000 residents) were provided with scientific literature focused on antimicrobial resistance and the appropriateness of use of specific antibiotics, together with local data on antimicrobial resistance and prescribing reports comparing each paediatrician with colleagues in the same district and with local averages. Prescribing rates of specific target antibiotics/classes of antibiotics were evaluated by comparing Reggio-Emilia with the other seven LHAs of the Emilia-Romagna Region (control area), adjusting for prescriptions during a 2-year baseline period. RESULTS: A significant increase in the rate of amoxicillin prescriptions (91 more per 1000 children/year) was observed in the intervention area compared with the control area along with a significant reduction in the rate of amoxicillin+clavulanate prescriptions (70 fewer per 1000 children/year) and a significant increase in the ratio of their prescription rates. No differences were observed in cephalosporin and macrolide prescription rates and overall antibiotic prescriptions. CONCLUSIONS: Improvements in prescribing appropriateness were observed. This study confirms the importance of an audit and feedback approach through small group meetings supported by scientific literature, local resistance data and prescribing reports. Such approach should always be considered as part of multifaceted interventions to promote AMS.

Atypical Presentation of Invasive Aspergillosis during Treatment with Mogamulizumab.

Treatment with CCR-4 antagonists has been shown to be protective against the development of invasive pulmonary aspergillosis in animal models. Herein, we present a case of fatal invasive pulmonary aspergillosis in a patient receiving Mogamulizumab. A 64-year-old man with refractory mycosis fungoides was found to have diffuse bilateral pulmonary nodules during a chest CT in June 2022. Bronchoalveolar lavage (BAL) fungal and bacterial cultures and galactomannan were negative, as well as serum beta-glucan and galactomannan. Histology showed a lymphoid infiltrate with a negative fungal stain, so a presumptive diagnosis of lymphoma infiltration was made, and the patient started the CCR-4 antagonist Mogamulizumab treatment in August 2022. He had no symptoms until November when he presented to the hematology clinic reporting dyspnea. He had neutrophilic leukocytosis (18.610 cells/µL), his c-reactive protein was 27 mg/dL, and his skin lesions from mycosis fungoides were just starting to improve. A CT scan showed large diffuse bilateral severely necrotic cavitated lesions with thick walls and apparently synchronous evolution. Beta-glucan was 31 pg/mL (wako method), while serum galactomannan 3.6. BAL was positive for Aspergillus fumigatus culture and galactomannan. Patient started voriconazole but, despite being in a stable condition, he suddenly died after two days. Discussion: Paradoxically, worsening of the chronic pulmonary aspergillosis has been reported after nivolumab treatment, and immune reconstitution syndromes are usually seen during neutrophil recovery after intensive chemotherapy. Our patient already presented indolent lung lesions from 5 months before and he remained completely asymptomatic until the aspergillosis diagnosis when he quickly passed away. Even if a progression of the lesions was expected in 5 months, this case had an atypical presentation. During the 5-month period, he had no pulmonary symptoms, and his c-reactive protein was negative. Furthermore, in the setting of the natural progression of subacute/chronic aspergillosis, a different radiological picture was expected with a less severe and probably asynchronous evolution. We think that the immune restoration associated with Mogamulizumab (also supported by the concurrent clinical response of the skin lesions) could have been detrimental in this case, exacerbating a catastrophic immune response or alternatively masquerading the clinical progression of aspergillosis. Clinicians should be aware of immune reconstitution syndromes possibly leading to fatal outcomes in immunocompromised patients starting CCR-4 antagonists.

Comparable cytokine release ex-vivo by whole blood from COVID-19 patients with and without non-invasive ventilation.

T cells are key players in the resolution of the infection by SARS-CoV-2. A delay in their activation can lead to severe COVID-19. The present work aimed to identify differences in cytokine release by T cells ex-vivo between COVID-19 patients in the acute phase, showing diverse disease severity. Concentrations of IFNγ, Granzyme B, IL-6, IL-10, IL-17A, IL-18, IP-10, MCP-1, and TNFα were evaluated after stimulation ex-vivo of whole blood samples with peptides from SARS-CoV-2 spike protein and a mitogen as well as without stimulation. Samples derived from hospitalized COVID-19 patients and SARS-CoV-2 vaccinated controls (CTR). Patients were classified on disease severity considering the necessity of non-invasive ventilation (NIV). Samples from patients requiring NIV revealed a similar release of cytokines compared with patients without NIV. COVID-19 patients showed higher spontaneous production of IFNγ and IP-10, lower production of MCP-1 after SARS-CoV-2 peptide stimulation and lower production of IFNγ, IL-10, IL-17A, Granzyme B, IP-10 after mitogenic stimulus compared with CTR. In conclusion, differences in T cell responses evaluated ex-vivo by a whole blood-based cytokine release assay do not appear to explain the need for non-invasive ventilation in COVID-19 patients.

Impact of COVID-19 pandemic on outpatient visit volume in cancer patients: Results of COMETA multicenter retrospective observational study.

Objective: To evaluate the impact of the COVID-19 pandemic on first and follow-up visits for cancer outpatients. Methods: This is a multicenter retrospective observational study involving three Comprehensive Cancer Care Centers (CCCCs): IFO, including IRE and ISG in Rome, AUSL-IRCCS of Reggio Emilia, and IRCCS Giovanni Paolo II in Bari) and one oncology department in a Community Hospital (Saint'Andrea Hospital, Rome). From 1 January 2020 and 31 December 2021, we evaluated the volume of outpatient consultations (first visits and follow-up), comparing them with the pre-pandemic year (2019). Results were analyzed by quarter according to the Rt (real-time indicator used to assess the evolution of the pandemic). IFO and IRCCS Giovanni Paolo II were "COVID-free" while AUSL-IRCCS RE was a "COVID-mixed" Institute. Depending on the Rt, Sain't Andrea Hospital experienced a "swinging" organizational pathway (COVID-free/ COVID-mixed). Results: Regarding the "first appointments", in 2020 the healthcare facilities operating in the North and Center of Italy showed a downward trend. In 2021, only AUSL-IRCCS RE showed an upward trend. Regarding the "follow-up", only AUSL IRCCS RE showed a slight up-trend in 2020. In 2021, IFO showed an increasing trend, while S. Andrea Hospital showed a negative plateau. Surprisingly, IRCCS Giovanni Paolo II in Bari showed an uptrend for both first appointment and follow-ups during pandemic and late pandemic except for the fourth quarter of 2021. Conclusions: During the first pandemic wave, no significant difference was observed amongst COVID-free and COVID-mixed Institutes and between CCCCs and a Community Hospital. In 2021 ("late pandemic year"), it has been more convenient to organize COVID-mixed pathway in the CCCCs rather than to keep the Institutions COVID-free. A swinging modality in the Community Hospital did not offer positive results in term of visit volumes. Our study about the impact of COVID-19 pandemic on visit volume in cancer outpatients may help health systems to optimize the post-pandemic use of resources and improve healthcare policies.

Looking over toxin-K(+) channel interactions. Clues from the structural and functional characterization of α-KTx toxin Tc32, a Kv1.3 channel blocker.

α-KTx toxin Tc32, from the Amazonian scorpion Tityus cambridgei, lacks the dyad motif, including Lys27, characteristic of the family and generally associated with channel blockage. The toxin has been cloned and expressed for the first time. Electrophysiological experiments, by showing that the recombinant form blocks Kv1.3 channels of olfactory bulb periglomerular cells like the natural Tc32 toxin, when tested on the Kv1.3 channel of human T lymphocytes, confirmed it is in an active fold. The nuclear magnetic resonance-derived structure revealed it exhibits an α/ß scaffold typical of the members of the α-KTx family. TdK2 and TdK3, all belonging to the same α-KTx 18 subfamily, share significant sequence identity with Tc32 but diverse selectivity and affinity for Kv1.3 and Kv1.1 channels. To gain insight into the structural features that may justify those differences, we used the recombinant Tc32 nuclear magnetic resonance-derived structure to model the other two toxins, for which no experimental structure is available. Their interaction with Kv1.3 and Kv1.1 has been investigated by means of docking simulations. The results suggest that differences in the electrostatic features of the toxins and channels, in their contact surfaces, and in their total dipole moment orientations govern the affinity and selectivity of toxins. In addition, we found that, regardless of whether the dyad motif is present, it is always a Lys side chain that physically blocks the channels, irrespective of its position in the toxin sequence.

Tocilizumab or glucocorticoids treatment for patients with SARS-CoV-2 pneumonia: An observational study.

OBJECTIVE: To estimate the effect of tocilizumab or glucocorticoids in preventing death and intubation in patients hospitalized with SARS-CoV-2 pneumonia. METHODS: This was a retrospective cohort study enrolling all consecutive patients hospitalized at Reggio Emilia AUSL between February the 11th and April 14th 2020 for severe COVID-19 and treated with tocilizumab or glucocorticoids (at least 80 mg/day of methylprednisolone or equivalent for at least 3 days). The primary outcome was death within 30 days from the start of the considered therapies. The secondary outcome was a composite outcome of death and/or intubation. All patients have been followed-up until May 19th 2020, with a follow-up of at least 30 days for every patient. To reduce confounding due to potential non-comparability of the two groups, those receiving tocilizumab and those receiving glucocorticoids, a propensity score was calculated as the inverse probability weighting of receiving treatment conditional on the baseline covariates. RESULTS AND CONCLUSION: Therapy with tocilizumab alone was associated with a reduction of deaths (OR 0.49, 95% CI 0.21-1.17) and of the composite outcome death/intubation (OR 0.35, 95% CI 0.13-0.90) compared to glucocorticoids alone. Nevertheless, this result should be cautiously interpreted due to a potential prescription bias.

Predictors of Virological Failure Among People Living with HIV Switching from an Effective First-Line Antiretroviral Regimen.

Aim of this study was to assess the predictors of virological failure (VF) among patients living with HIV (PLWHIV) switching from an effective first-line antiretroviral therapy (ART) regimen, and to evaluate the emergence of resistance-associated mutations. All adult patients enrolled in the Antiviral Response Cohort Analysis cohort who started ART after 2010, with at least 6 months of virological suppression (VS) before ART switch and with an available genotypic resistance test (GRT) at baseline were included. Thirty-two patients out of the 607 PLWHIV included (5.3%) experienced VF after a median of 11 months from ART switch. Younger age (adjusted Hazard Ratio [aHR] 0.96, 95% confidence interval [CI] 0.92-0.99, p = .023), being male who have sex with male (aHR 0.15, 95% CI 0.03-0.69, p = .014), and longer time from VS to ART switch (aHR 0.97, 95% CI 0.95-1.00, p = .021) resulted protective toward VF, while receiving a first-line regimen containing a backbone other than ABC/3TC or TXF/FTC (aHR 3.61, 95% CI 1.00-13.1, p = .050) and a boosted protease inhibitor as anchor drug (aHR 3.34, 95% CI 1.20-9.28, p = .021) were associated with higher risk of VF. GRT at the moment of VF was available only for 13 patients (40.6%). ART switch in patients with stable control of HIV infection is a safe practice, even if particular attention should be paid in certain cases of patients switching from regimens containing low-performance backbones or protease inhibitors.

Predictive factors of clinical outcomes in patients with COVID-19 treated with tocilizumab: A monocentric retrospective analysis.

OBJECTIVE: The aim of this retrospective observational study is to analyse clinical, serological and radiological predictors of outcome in patients with COVID-19 pneumonia treated with tocilizumab, providing clinical guidance to its use in real-life. METHOD: This is a retrospective, monocentric observational cohort study. All consecutive patients hospitalized between February the 11th and April 14th 2020 for severe COVID-19 pneumonia at Reggio Emilia AUSL and treated with tocilizumab were enrolled. The patient's clinical status was recorded every day using the WHO ordinal scale for clinical improvement. Response to treatment was defined as an improvement of one point (from the status at the beginning of tocilizumab treatment) during the follow-up on this scale. Bivariate association of main patients' characteristics with outcomes was explored by descriptive statistics and Fisher or Kruskal Wallis tests (respectively for qualitative or quantitative variables). Each clinically significant predictor was checked by a loglikelihood ratio test (in univariate logistic models for each of the considered outcomes) against the null model. RESULTS: A total of 173 patients were included. Only hypertension, the use of angiotensin-converting enzyme inhibitors, PaO2/FiO2, respiratory rate and C-reactive protein were selected for the multivariate analysis. In the multivariable model, none of them was significantly associated with response. CONCLUSIONS: Evaluating a large number of clinical variables, our study did not find new predictors of outcome in COVID19 patients treated with tocilizumab. Further studies are needed to investigate the use of tocilizumab in COVID-19 and to better identify clinical phenotypes which could benefit from this treatment.

Thermal stability, ligand binding and allergenicity data of Mus m 1.0102 allergen and its cysteine mutants.

The presented data were obtained with the lipocalin allergen Mus m 1.0102 and its cysteine mutants MM-C138A, MM-C157A and MM-C138,157A, whose structural features and unfold reversibility investigations are presented in the research article entitled "The allergen Mus m 1.0102: cysteine residues and molecular allergology" [1]. The data were obtained by means of a Dynamic Light Scattering-based thermal stability assay, a Fluorescence-based ligand-binding assay and a basophil degranulation test, and describe proteins' fold stability, ligand binding ability and allergenic potential, respectively. Analysis of the collected data produced the temperatures corresponding to the onset of the protein unfolding, the dissociation constants for N-Phenyl-1-naphthylamine ligand and the profiles of ß-hexosaminidase release from RBL SX-38 cells, sensitized with the serum of selected allergic patients and incubated with increasing antigens concentrations. These data allow for comparison of the lipocalin allergen Mus m 1.0102 with its conserved cysteines mutants and, with regard to their potential application in allergy diagnostics and immunotherapy, they contribute to the process of recombinant allergen characterization and standardization.

The allergen Mus m 1.0102: Cysteine residues and molecular allergology.

Mus m 1.0102 is a member of the mouse Major Urinary Protein family, belonging to the Lipocalins superfamily. Major Urinary Proteins (MUPs) are characterized by highly conserved structural motifs. These include a disulphide bond, involved in protein oxidative folding and protein structure stabilization, and a free cysteine residue, substituted by serine only in the pheromonal protein Darcin (MUP20). The free cysteine is recognized as responsible for the onset of inter- or intramolecular thiol/disulphide exchange, an event that favours protein aggregation. Here we show that the substitution of selected cysteine residues modulates Mus m 1.0102 protein folding, fold stability and unfolding reversibility, while maintaining its allergenic potency. Recombinant allergens used for immunotherapy or employed in allergy diagnostic kits require, as essential features, conformational stability, sample homogeneity and proper immunogenicity. In this perspective, recombinant Mus m 1.0102 might appear reasonably adequate as lead molecule because of its allergenic potential and thermal stability. However, its modest resistance to aggregation renders the protein unsuitable for pharmacological preparations. Point mutation is considered a winning strategy. We report that, among the tested mutants, C138A mutant acquires a structure more resistant to thermal stress and less prone to aggregation, two events that act positively on the protein shelf life. Those features make that MUP variant an attractive lead molecule for the development of a diagnostic kit and/or a vaccine.

Diatom Allantoin Synthase Provides Structural Insights into Natural Fusion Protein Therapeutics.

Humans have lost the ability to convert urate into the more soluble allantoin with the evolutionary inactivation of three enzymes of the uricolytic pathway. Restoration of this function through enzyme replacement therapy can treat severe hyperuricemia and Lesch-Nyhan disease. Through a genomic exploration of natural gene fusions, we found that plants and diatoms independently evolved a fusion protein (allantoin synthase) complementing two human pseudogenes. The 1.85-Å-resolution crystal structure of allantoin synthase from the diatom Phaeodactylum tricornutum provides a rationale for the domain combinations observed in the metabolic pathway, suggesting that quaternary structure is key to the evolutionary success of protein domain fusions. Polyethylene glycol (PEG) conjugation experiments indicate that a PEG-modified form of the natural fusion protein provides advantages over separate enzymes in terms of activity maintenance and manufacturing of the bioconjugate. These results suggest that the combination of different activities in a single molecular unit can simplify the production and chemical modification of recombinant proteins for multifunctional enzyme therapy.

Correction: Real-life data on potential drug-drug interactions in patients with chronic hepatitis C viral infection undergoing antiviral therapy with interferon-free DAAs in the PITER Cohort Study.

[This corrects the article DOI: 10.1371/journal.pone.0172159.].

Tocilizumab or glucocorticoids treatment for patients with SARS-CoV-2 pneumonia: An observational study

Abstract Objective To estimate the effect of tocilizumab or glucocorticoids in preventing death and intubation in patients hospitalized with SARS-CoV-2 pneumonia. Methods This was a retrospective cohort study enrolling all consecutive patients hospitalized at Reggio Emilia AUSL between February the 11th and April 14th 2020 for severe COVID-19 and treated with tocilizumab or glucocorticoids (at least 80 mg/day of methylprednisolone or equivalent for at least 3 days). The primary outcome was death within 30 days from the start of the considered therapies. The secondary outcome was a composite outcome of death and/or intubation. All patients have been followed-up until May 19th 2020, with a follow-up of at least 30 days for every patient. To reduce confounding due to potential non-comparability of the two groups, those receiving tocilizumab and those receiving glucocorticoids, a propensity score was calculated as the inverse probability weighting of receiving treatment conditional on the baseline covariates. Results and conclusion Therapy with tocilizumab alone was associated with a reduction of deaths (OR 0.49, 95% CI 0.21-1.17) and of the composite outcome death/intubation (OR 0.35, 95% CI 0.13-0.90) compared to glucocorticoids alone. Nevertheless, this result should be cautiously interpreted due to a potential prescription bias.