The Receptor Binding Domain of SARS-CoV-2 Lambda Variant Has a Better Chance Than the Delta Variant in Evading BNT162b2 COVID-19 mRNA Vaccine-Induced Humoral Immunity.

The SARS-CoV-2 Delta and Lambda variants had been named variants of concern (VOC) and variants of interest (VOI), respectively, by the World Health Organization (WHO). Both variants have two mutations in the spike receptor binding domain (RBD) region, with L452R and T478K mutations in the Delta variant, and L452Q and F490S mutations in the Lambda variant. We used surface plasmon resonance (SPR)-based technology to evaluate the effect of these mutations on human angiotensin-converting enzyme 2 (ACE2) and Bamlanivimab binding. The affinity for the RBD ligand, ACE2, of the Delta RBD is approximately twice as strong as that of the wild type RBD, an increase that accounts for the increased infectivity of the Delta variant. On the other hand, in spite of its amino acid changes, the Lambda RBD has similar affinity to ACE2 as the wild type RBD. The protective anti-wild type RBD antibody Bamlanivimab binds very poorly to the Delta RBD and not at all to the Lambda RBD. Nevertheless, serum antibodies from individuals immunized with the BNT162b2 vaccine were found to bind well to the Delta RBD, but less efficiently to the Lambda RBD in contrast. As a result, the blocking ability of ACE2 binding by serum antibodies was decreased more by the Lambda than the Delta RBD. Titers of sera from BNT162b2 mRNA vaccinated individuals dropped 3-fold within six months of vaccination regardless of whether the target RBD was wild type, Delta or Lambda. This may account partially for the fall off with time in the protective effect of vaccines against any variant.

A rare case report of polyangiitis overlap syndrome: granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis.

BACKGROUND: Granulomatosis with polyangiitis (GPA) is a systemic ANCA-associated vasculitis characterized by necrotizing granulomatous inflammation and a predilection for the upper and lower respiratory tract. Eosinophilic granulomatosis with polyangiitis (EGPA) is also a systemic ANCA-associated vasculitis, but EGPA is characterized by eosinophilic as well as granulomatous inflammation and is more commonly associated with asthma and eosinophilia. Polyangiitis overlap syndrome is defined as systemic vasculitis that does not fit precisely into a single category of classical vasculitis classification and/or overlaps with more than one category. Several polyangiitis overlap syndromes have been identified, however, there are very few case reports of an overlap syndrome involving both GPA and EGPA in the medical literature. CASE PRESENTATION: We conducted a PUBMED literature review using key words 'granulomatosis with polyangiitis,' 'Wegener's,' 'GPA,' 'eosinophilic granulomatosis with polyangiitis,' 'Churg-Strauss,' 'EGPA,' 'overlap syndrome,' 'Wegener's with eosinophilia,' and 'GPA with eosinophilia' in English only journals from 1986 to 2017. Relevant case reports and review articles of overlap syndromes of GPA and EGPA were identified. We aim to report a unique case of GPA and EGPA overlap syndrome and review the cases that have been previously described. Between 1986 and 2017, we identified 15 cases that represent an overlap syndrome with compelling features of both GPA and EGPA. Patients ranged in age between 21 and 78. Of those whose gender was identified, 80 % of the patients were female. All cases described involved the lungs, 60 % reported sinus involvement, and more than 50 % displayed renal involvement. An overwhelming majority of patients were positive for c-ANCA and demonstrated eosinophilia (peripheral blood or tissue eosinophilia). A preponderance of the cases described were treated with systemic corticosteroids combined with an immunosuppressive/cytotoxic agents. CONCLUSION: To our knowledge, there have been very few cases reported of an overlap syndrome of GPA and EGPA. Identification of patients with a polyangiitis overlap syndrome of GPA and EGPA is imperative as prognosis, longitudinal management and treatment modalities may differ between these entities.

A Randomized Trial of an Intensive Physical Therapy Program for Patients with Acute Respiratory Failure.

RATIONALE: Early physical therapy (PT) interventions may benefit patients with acute respiratory failure by preventing or attenuating neuromuscular weakness. However, the optimal dosage of these interventions is currently unknown. OBJECTIVES: To determine whether an intensive PT program significantly improves long-term physical functional performance compared with a standard-of-care PT program. METHODS: Patients who required mechanical ventilation for at least 4 days were eligible. Enrolled patients were randomized to receive PT for up to 4 weeks delivered in an intensive or standard-of-care manner. Physical functional performance was assessed at 1, 3, and 6 months in survivors who were not currently in an acute or long-term care facility. The primary outcome was the Continuous Scale Physical Functional Performance Test short form (CS-PFP-10) score at 1 month. MEASUREMENTS AND MAIN RESULTS: A total of 120 patients were enrolled from five hospitals. Patients in the intensive PT group received 12.4 ± 6.5 sessions for a total of 408 ± 261 minutes compared with only 6.1 ± 3.8 sessions for 86 ± 63 minutes in the standard-of-care group (P < 0.001 for both analyses). Physical function assessments were available for 86% of patients at 1 month, for 76% at 3 months, and for 60% at 6 months. In both groups, physical function was reduced yet significantly improved over time between 1, 3, and 6 months. When we compared the two interventions, we found no differences in the total CS-PFP-10 scores at all three time points (P = 0.73, 0.29, and 0.43, respectively) or in the total CS-PFP-10 score trajectory (P = 0.71). CONCLUSIONS: An intensive PT program did not improve long-term physical functional performance compared with a standard-of-care program. Clinical trial registered with www.clinicaltrials.gov (NCT01058421).

Effect of Ganciclovir on IL-6 Levels Among Cytomegalovirus-Seropositive Adults With Critical Illness: A Randomized Clinical Trial.

Importance: The role of cytomegalovirus (CMV) reactivation in mediating adverse clinical outcomes in nonimmunosuppressed adults with critical illness is unknown. Objective: To determine whether ganciclovir prophylaxis reduces plasma interleukin 6 (IL-6) levels in CMV-seropositive adults who are critically ill. Design, Setting, and Participants: Double-blind, placebo-controlled, randomized clinical trial (conducted March 10, 2011-April 29, 2016) with a follow-up of 180 days (November 10, 2016) that included 160 CMV-seropositive adults with either sepsis or trauma and respiratory failure at 14 university intensive care units (ICUs) across the United States. Interventions: Patients were randomized (1:1) to receive either intravenous ganciclovir (5 mg/kg twice daily for 5 days), followed by either intravenous ganciclovir or oral valganciclovir once daily until hospital discharge (n = 84) or to receive matching placebo (n = 76). Main Outcomes and Measures: The primary outcome was change in IL-6 level from day 1 to 14. Secondary outcomes were incidence of CMV reactivation in plasma, mechanical ventilation days, incidence of secondary bacteremia or fungemia, ICU length of stay, mortality, and ventilator-free days (VFDs) at 28 days. Results: Among 160 randomized patients (mean age, 57 years; women, 43%), 156 patients received 1or more dose(s) of study medication, and 132 patients (85%) completed the study. The mean change in plasma IL-6 levels between groups was -0.79 log10 units (-2.06 to 0.48) in the ganciclovir group and -0.79 log10 units (-2.14 to 0.56) in the placebo group (point estimate of difference, 0 [95% CI, -0.3 to 0.3]; P > .99). Among secondary outcomes, CMV reactivation in plasma was significantly lower in the ganciclovir group (12% [10 of 84 patients] vs 39% [28 of 72 patients]); absolute risk difference, -27 (95% CI, -40 to -14), P < .001. The ganciclovir group had more median VFDs in both the intention-to-treat (ITT) group and in the prespecified sepsis subgroup (ITT group: 23 days in ganciclovir group vs 20 days in the placebo group, P = .05; sepsis subgroup, 23 days in the ganciclovir group vs 20 days in the placebo group, P = .03). There were no significant differences between the ganciclovir and placebo groups in duration of mechanical ventilation (5 days for the ganciclovir group vs 6 days for the placebo group, P = .16), incidence of secondary bacteremia or fungemia (15% for the ganciclovir group vs 15% for the placebo group, P = .67), ICU length of stay (8 days for the ganciclovir group vs 8 days for the placebo group, P = .76), or mortality (12% for the ganciclovir group vs 15% for the placebo group, P = .54). Conclusions and Relevance: Among CMV-seropositive adults with critical illness due to sepsis or trauma, ganciclovir did not reduce IL-6 levels and the current study does not support routine clinical use of ganciclovir as a prophylactic agent in patients with sepsis. Additional research is necessary to determine the clinical efficacy and safety of CMV suppression in this setting. Trial Registration: clinicaltrials.gov Identifier: NCT01335932.

Predictors of mortality in rheumatoid arthritis-associated interstitial lung disease.

Interstitial lung disease (ILD) is a common pulmonary manifestation of rheumatoid arthritis. There is lack of clarity around predictors of mortality and disease behaviour over time in these patients.We identified rheumatoid arthritis-related interstitial lung disease (RA-ILD) patients evaluated at National Jewish Health (Denver, CO, USA) from 1995 to 2013 whose baseline high-resolution computed tomography (HRCT) scans showed either a nonspecific interstitial pneumonia (NSIP) or a "definite" or "possible" usual interstitial pneumonia (UIP) pattern. We used univariate, multivariate and longitudinal analytical methods to identify clinical predictors of mortality and to model disease behaviour over time.The cohort included 137 subjects; 108 had UIP on HRCT (RA-UIP) and 29 had NSIP on HRCT (RA-NSIP). Those with RA-UIP had a shorter survival time than those with RA-NSIP (log rank p=0.02). In a model controlling for age, sex, smoking and HRCT pattern, a lower baseline % predicted forced vital capacity (FVC % pred) (HR 1.46; p<0.0001) and a 10% decline in FVC % pred from baseline to any time during follow up (HR 2.57; p<0.0001) were independently associated with an increased risk of death.Data from this study suggest that in RA-ILD, disease progression and survival differ between subgroups defined by HRCT pattern; however, when controlling for potentially influential variables, pulmonary physiology, but not HRCT pattern, independently predicts mortality.

Rituximab as successful adjunct treatment in a patient with disseminated nontuberculous mycobacterial infection due to acquired anti-interferon-γ autoantibody.

An acquired immune deficiency due to interferon gamma (IFN-γ) autoantibodies was diagnosed in a 78-year-old Japanese man with treatment-refractory disseminated nontuberculous mycobacterial infection. In addition to standard antimycobacterial therapy, he was successfully treated with rituximab to eliminate B cells and thereby the autoantibody. Subsequently, he obtained a sustained remission from infection.

Increased cell surface Fas expression is necessary and sufficient to sensitize lung fibroblasts to Fas ligation-induced apoptosis: implications for fibroblast accumulation in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is associated with the accumulation of collagen-secreting fibroblasts and myofibroblasts in the lung parenchyma. Many mechanisms contribute to their accumulation, including resistance to apoptosis. In previous work, we showed that exposure to the proinflammatory cytokines TNF-α and IFN-γ reverses the resistance of lung fibroblasts to apoptosis. In this study, we investigate the underlying mechanisms. Based on an interrogation of the transcriptomes of unstimulated and TNF-α- and IFN-γ-stimulated primary lung fibroblasts and the lung fibroblast cell line MRC5, we show that among Fas-signaling pathway molecules, Fas expression was increased ∼6-fold in an NF-κB- and p38(mapk)-dependent fashion. Prevention of the increase in Fas expression using Fas small interfering RNAs blocked the ability of TNF-α and IFN-γ to sensitize fibroblasts to Fas ligation-induced apoptosis, whereas enforced adenovirus-mediated Fas overexpression was sufficient to overcome basal resistance to Fas-induced apoptosis. Examination of lung tissues from IPF patients revealed low to absent staining of Fas in fibroblastic cells of fibroblast foci. Collectively, these findings suggest that increased expression of Fas is necessary and sufficient to overcome the resistance of lung fibroblasts to Fas-induced apoptosis. Our findings also suggest that approaches aimed at increasing Fas expression by lung fibroblasts and myofibroblasts may be therapeutically relevant in IPF.

The pulmonary vasculitides.

The pulmonary vasculitides are a rare group of heterogeneous disorders unified by the histopathologic finding of inflammation and destruction of the blood vessel wall. Diagnosis of these disorders is exceptionally challenging, given their highly variable clinical presentation, their relative rarity, and the overlap of the signs and symptoms of vasculitis with much more common entities. However, advances in the management of vasculitis allow for accurate diagnosis, risk stratification in the individual patient, and the implementation of evidence-based, effective pharmacologic therapies. This concise clinical review addresses the diagnosis and management of the patient with pulmonary vasculitis and provides an up-to-date review of the state of the field.

The Lambda variant of SARS-CoV-2 has a better chance than the Delta variant to escape vaccines.

The newly emerging variants of SARS-CoV-2 from India (Delta variant) and South America (Lambda variant) have led to a higher infection rate of either vaccinated or unvaccinated people. We found that sera from Pfizer-BioNTech vaccine remain high reactivity toward the receptor binding domain (RBD) of Delta variant while it drops dramatically toward that of Lambda variant. Interestingly, the overall titer of antibodies of Pfizer-BioNTech vaccinated individuals drops 3-fold after 6 months, which could be one of major reasons for breakthrough infections, emphasizing the importance of potential third boost shot. While a therapeutic antibody, Bamlanivimab, decreases binding affinity to Delta variant by ~20 fold, it fully lost binding to Lambda variant. Structural modeling of complexes of RBD with human receptor, Angiotensin Converting Enzyme 2 (ACE2), and Bamlanivimab suggest the potential basis of the change of binding. The data suggest possible danger and a potential surge of Lambda variant in near future.

501Y.V2 and 501Y.V3 variants of SARS-CoV-2 lose binding to bamlanivimab in vitro.

The newly emerging variants of SARS-CoV-2 from South Africa (B.1.351/501Y.V2) and Brazil (P.1/501Y.V3) have led to a higher infection rate and reinfection of COVID-19 patients. We found that the mutations K417N, E484K, and N501Y within the receptor-binding domains (RBDs) of the virus could confer ~2-fold higher binding affinity to the human receptor, angiotensin converting enzyme 2 (ACE2), compared to the wildtype RBD. The mutated version of RBD also completely abolishes the binding of bamlanivimab, a therapeutic antibody, in vitro. Detailed analysis shows that the ~10-fold gain of binding affinity between ACE2 and Y501-RBD, which also exits in the high contagious variant B.1.1.7/501Y.V1 from the United Kingdom, is compromised by additional introduction of the K417/N/T mutation. Mutation of E484K leads to the loss of bamlanivimab binding to RBD, although this mutation does not affect the binding between RBD and ACE2.

501Y.V2 and 501Y.V3 variants of SARS-CoV-2 lose binding to Bamlanivimab in vitro.

We generated several versions of the receptor binding domain (RBD) of the Spike protein with mutations existing within newly emerging variants from South Africa and Brazil. We found that the mutant RBD with K417N, E484K, and N501Y exchanges has higher binding affinity to the human receptor compared to the wildtype RBD. This mutated version of RBD also completely abolishes the binding to a therapeutic antibody, Bamlanivimab, in vitro .

The basis of a more contagious 501Y.V1 variant of SARS-COV-2.

Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) is causing a world-wide pandemic. A variant of SARS-COV-2 (20I/501Y.V1) recently discovered in the United Kingdom has a single mutation from N501 to Y501 within the receptor binding domain (Y501-RBD), of the Spike protein of the virus. This variant is much more contagious than the original version (N501-RBD). We found that this mutated version of RBD binds to human Angiotensin Converting Enzyme 2 (ACE2) a ~10 times more tightly than the native version (N501-RBD). Modeling analysis showed that the N501Y mutation would allow a potential aromatic ring-ring interaction and an additional hydrogen bond between the RBD and ACE2. However, sera from individuals immunized with the Pfizer-BioNTech vaccine still efficiently block the binding of Y501-RBD to ACE2 though with a slight compromised manner by comparison with their ability to inhibit binding to ACE2 of N501-RBD. This may raise the concern whether therapeutic anti-RBD antibodies used to treat COVID-19 patients are still efficacious. Nevertheless, a therapeutic antibody, Bamlanivimab, still binds to the Y501-RBD as efficiently as its binds to N501-RBD.

Compartmentalized expression of c-FLIP in lung tissues of patients with idiopathic pulmonary fibrosis.

Increased apoptosis of alveolar epithelial cells and impaired apoptosis of myofibroblasts have been linked to the pathogenesis of idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP). Fas, a death receptor of the TNF-receptor superfamily, has been implicated in apoptosis of both cell types, though the mechanisms are poorly understood. The goals of this study were: (1) to examine the localization of Fas-associated death-domain-like IL-1beta-converting enzyme inhibitory protein (c-FLIP), an NF-kappaB-dependent regulator of Fas-signaling, in lung tissues from IPF/UIP patients and control subjects; and (2) to compare c-FLIP expression with epithelial cell and myofibroblast apoptosis, proliferation, and NF-kappaB activation. c-FLIP expression was restricted to airway epithelial cells in control lung tissues. In contrast, in patients with IPF/UIP, c-FLIP was also expressed by alveolar epithelial cells in areas of injury and fibrosis, but was absent from myofibroblasts in fibroblastic foci and from alveolar epithelial cells in uninvolved areas of lung tissue. Quantification of apoptosis and proliferation revealed an absence of apoptotic or proliferating cells in fibroblastic foci and low levels of apoptosis and proliferation by alveolar epithelial cells. Quantification of NF-kappaB expression and nuclear translocation revealed strong staining and translocation in alveolar epithelial cells and weak staining and minimal nuclear translocation in myofibroblasts. These findings suggest that: (1) c-FLIP expression is induced in the abnormal alveolar epithelium of patients with IPF/UIP, (2) the resistance of myofibroblasts to apoptosis in patients with IPF/UIP occurs independently of c-FLIP expression, and (3) increased NF-kappaB activation and c-FLIP expression by the alveolar epithelium may be linked.

A detailed evaluation of acute respiratory decline in patients with fibrotic lung disease: aetiology and outcomes.

BACKGROUND AND OBJECTIVE: A comprehensive diagnostic evaluation is recommended for all patients with fibrotic lung disease and acute respiratory decompensation. However, the effect on clinical outcomes of this evaluation remains unknown. METHODS: We evaluated 27 consecutive patients with fibrotic lung disease who were hospitalized for an acute respiratory decline between June 2006 and April 2009. An interstitial lung disease expert assisted with the acute care of each patient. A retrospective review of the patient charts was performed to obtain demographic and clinical data, and to assess outcomes. RESULTS: Using a strict definition of acute exacerbation (AE) of fibrotic lung disease derived from the IPF Network Pulmonary Perspective statement, 10 of the 27 patients were classified as definite AE and nine as suspected AE. In eight patients, infectious agents were identified as potential explanations for the respiratory decline. No patients with congestive heart failure or pulmonary embolism were identified. Overall survival to discharge was 37.0%. One-year survival was 14.8%. There were no differences in outcomes for patients with AE compared with those for whom potential infectious aetiologies were identified (log rank, P = 0.932). Patients with IPF showed a decreased rate of survival compared with patients with non-IPF fibrotic disease (1-year survival 0% vs 28.6%, log rank, P = 0.045). CONCLUSIONS: In patients with fibrotic lung disease and an acute respiratory decline, a detailed diagnostic evaluation revealed a potential infectious aetiology in up to one-third of cases. However, there was no association between this finding and outcomes in these patients. One-year survival was dismal in patients who suffered an acute respiratory decompensation.

Update in idiopathic pulmonary fibrosis.

PURPOSE OF REVIEW: This review aims to highlight and place in context recent advances in and insights into the natural history, diagnosis, and management of idiopathic pulmonary fibrosis (IPF). RECENT FINDINGS: Although the diagnosis of IPF remains challenging, an evolution in systems of practice and advancing technologies are steadily improving diagnostic accuracy. The identification of concomitant pulmonary hypertension as well as acute exacerbations of the underlying disease have taken on increasing importance in the natural history of IPF. Similarly, the management of IPF remains challenging, and although a number of recent trials of novel investigational agents for the treatment of IPF yielded negative results, at least one of these trials showed significant benefit suggesting progress in the treatment of this disease. SUMMARY: Although IPF remains a diagnostic and therapeutic challenge to even the most experienced of clinicians, our knowledge of the natural history of the disease, diagnostic accuracy, and therapeutic approach continue to advance.

Acute exacerbations of fibrotic hypersensitivity pneumonitis: a case series.

BACKGROUND: It is now recognized that a significant portion of patients with idiopathic pulmonary fibrosis (IPF) can have sudden and rapid deteriorations in disease course that cannot be explained by infection, heart failure, or thromboembolic disease. These events are often fatal and have been termed acute exacerbations (AEs) of underlying disease. While best described in patients with IPF, they have also been reported in patients with other forms of interstitial lung disease. We sought to determine if this same phenomenon occurs in patients with hypersensitivity pneumonitis (HP). METHODS: We retrospectively reviewed our clinical experience at National Jewish Medical and Research Center for patients with surgical lung biopsy-proven fibrotic HP who had an acute decline in respiratory status and met criteria similar to those proposed for the diagnosis of an AE of IPF. RESULTS: Over a 2-year period, we identified four patients with an AE of fibrotic HP. All patients had a clinical course similar to that most frequently described in AEs of IPF: respiratory failure requiring assisted ventilation, lack of clinical response to high-dose corticosteroid therapy, and a poor prognosis (all cases resulted in death or emergent lung transplantation). Lung biopsy at the time of the AE, explant, or autopsy revealed organizing diffuse alveolar damage superimposed on fibrotic lung disease. CONCLUSIONS: Fibrotic HP, like other forms of fibrotic lung disease, can be associated with AEs of disease. Further investigation into similarities and pathways common in AEs of various fibrotic lung diseases may yield additional insight into this recently recognized syndrome.

A rare presentation of ischemic pseudomembranous colitis due to Escherichia coli O157:H7.

Escherichia coli Ol57:H7 infection ranges from mild diarrheal illness to severe hemorrhagic colitis but may rarely be complicated by pseudomembranous colitis and/or necrosis. Herein, we report a sporadic case of ischemic E. coli Ol57:H7 pseudomembranous colitis in an adult that occurred during a national outbreak of E. coli Ol57:H7 in the United States.

Pericardial abnormalities predict the presence of echocardiographically defined pulmonary arterial hypertension in systemic sclerosis-related interstitial lung disease.

OBJECTIVES: To determine the prevalence and significance of pericardial abnormalities in systemic sclerosis (SSc)-related interstitial lung disease (ILD). METHODS: Retrospective study of 41 subjects with SSc-related ILD who underwent evaluation including thoracic high-resolution CT (HRCT) imaging, transthoracic echocardiography (TTE), and pulmonary function testing. HRCT review evaluated the pericardium for the presence of pericardial effusion (PEf), thickness of the anterior pericardial recess (APR) [abnormal defined as > 10 mm], and pericardial thickening as calculated by total pericardial score (TPS) [abnormal defined as > 8 mm]. Pulmonary arterial hypertension (PAH) was defined as a pulmonary artery pressure > 35 mm Hg estimated by TTE. RESULTS: Fifty-nine percent had an abnormal pericardium, 49% had a PEf, 56% had an abnormal APR, and 49% had an abnormal TPS. An abnormal pericardium was more common in men than women. Subjects with and without pericardial abnormalities were otherwise similar with respect to age, SSc classification, autoantibodies, ILD radiographic pattern, and presence of esophageal dilation. Both groups had similar median percentage of predicted total lung capacity, percentage of predicted FVC, percentage of predicted FEV(1), and percentage of predicted diffusion capacity of the lung for carbon monoxide. Subjects with pericardial abnormalities were more likely to have coexistent PAH (35% vs 75%; p = 0.02) and a higher median right ventricular systolic pressure (31 mm Hg vs 44 mm Hg; p = 0.03). Multiple logistic regression revealed that TPS was the best individual predictor of the presence of TTE-defined PAH. CONCLUSIONS: In patients with SSc-related ILD, pericardial abnormalities are commonly seen on HRCT, and their presence is strongly associated with echocardiographically defined PAH, with abnormal TPS as the best individual predictor.