SARS-CoV-2 infections in patients enrolled on the Children's Oncology Group standard-risk B-cell acute lymphoblastic leukemia trial, AALL1731.

Hematologic malignancy is a risk factor for severe coronavirus disease 2019 (COVID-19) in adults; however, data specific to children with leukemia are limited. High-quality infectious adverse event data from the ongoing Children's Oncology Group (COG) standard-risk B acute lymphoblastic leukemia/lymphoma (ALL/LLy) trial, AALL1731, were analyzed to provide a disease-specific estimate of SARS-CoV-2 infection outcomes in pediatric ALL. Of 253 patients with reported infections, the majority (77.1%) were asymptomatic or mildly symptomatic (CTCAE grade 1/2) and there was a single COVID-19-related death. These data suggest SARS-CoV-2 infection does not confer substantial morbidity among young patients with B-lymphoblastic leukemia/lymphoma (B-ALL/LLy).

Collaborative team dynamics and scholarly outcomes of multidisciplinary research teams: A mixed-methods approach.

Introduction: Impactful, transdisciplinary scientific discoveries are created by teams of researchers spanning multiple disciplines, but collaboration across disciplines can be challenging. We examined how team dynamics and collaboration are related to successes and barriers faced by teams of researchers from multiple disciplines. Methods: A mixed-methods approach was used to examine 12 research teams granted multidisciplinary pilot awards. Team members were surveyed to assess their team dynamics and individual views about transdisciplinary research. Forty-seven researchers (59.5%) responded, including two to eight members from each funded team. Associations were examined between collaborative dynamics and scholarly product outcomes, including manuscripts, grant proposals, and awarded grants. One member from each team was selected for an in-depth interview to contextualize and extend information about collaborative processes, successes, and barriers to performing transdisciplinary research. Results: Quality of team interactions was positively associated with achievement of scholarly products (r = 0.64, p = 0.02). Satisfaction with team members (r = 0.38) and team collaboration scores (r = 0.43) also demonstrated positive associations with achievement of scholarly products, but these were not statistically significant. Qualitative results support these findings and add further insight into aspects of the collaborative process that were particularly important to foster success on multidisciplinary teams. Beyond scholarly metrics, additional successes from the multidisciplinary teams were identified through the qualitative portion of the study including career development and acceleration for early career researchers. Conclusions: Both the quantitative and qualitative study results indicate that effective collaboration is critical to multidisciplinary research team success. Development and/or promotion of team science-based trainings for researchers would promote these collaborative skills.

Improving infectious adverse event reporting for children and adolescents enrolled in clinical trials for acute lymphoblastic leukemia: A report from the Children's Oncology Group.

Infections cause substantial morbidity for children with acute lymphoblastic leukemia (ALL). Therefore, accurate characterization of infectious adverse events (AEs) reported on clinical trials is imperative to defining, comparing, and managing safety and toxicity. Here, we describe key processes implemented to improve reporting of infectious AEs on two active phase III Children's Oncology Group (COG) ALL trials. Processes include: (a) identifying infections as a targeted toxicity, (b) incorporation of infection-specific case report form questions, and (c) physician review of AEs with real-time data cleaning. Preliminary assessment of these processes suggests improved reporting, as well as opportunities for further improvement.

Serum Amyloid A Is an Exchangeable Apolipoprotein.

Objective- SAA (serum amyloid A) is a family of acute-phase reactants that have proinflammatory and proatherogenic activities. SAA is more lipophilic than apoA-I (apolipoprotein A-I), and during an acute-phase response, <10% of plasma SAA is found lipid-free. In most reports, SAA is found exclusively associated with high-density lipoprotein; however, we and others have reported SAA on apoB (apolipoprotein B)-containing lipoproteins in both mice and humans. The goal of this study was to determine whether SAA is an exchangeable apolipoprotein. Approach and Results- Delipidated human SAA was incubated with SAA-free human lipoproteins; then, samples were reisolated by fast protein liquid chromatography, and SAA analyzed by ELISA and immunoblot. Both in vitro and in vivo, we show that SAA associates with any lipoprotein and does not remain in a lipid-free form. Although SAA is preferentially found on high-density lipoprotein, it can exchange between lipoproteins. In the presence of CETP (cholesterol ester transfer protein), there is greater exchange of SAA between lipoproteins. Subjects with diabetes mellitus, but not those with metabolic syndrome, showed altered SAA lipoprotein distribution postprandially. Proteoglycan-mediated lipoprotein retention is thought to be an underlying mechanism for atherosclerosis development. SAA has a proteoglycan-binding domain. Lipoproteins containing SAA had increased proteoglycan binding compared with SAA-free lipoproteins. Conclusions- Thus, SAA is an exchangeable apolipoprotein and increases apoB-containing lipoproteins' proteoglycan binding. We and others have previously reported the presence of SAA on low-density lipoprotein in individuals with obesity, diabetes mellitus, and metabolic syndrome. We propose that the presence of SAA on apoB-containing lipoproteins may contribute to cardiovascular disease development in these populations.

Serum amyloid A3 is pro-atherogenic.

BACKGROUND AND AIMS: Serum amyloid A (SAA) predicts cardiovascular events. Overexpression of SAA increases atherosclerosis development; however, deficiency of two of the murine acute phase isoforms, SAA1.1 and SAA2.1, has no effect on atherosclerosis. SAA3 is a pseudogene in humans, but is an expressed acute phase isoform in mice. The goal of this study was to determine if SAA3 affects atherosclerosis in mice. METHODS: ApoE-/- mice were used as the model for all studies. SAA3 was overexpressed by an adeno-associated virus or suppressed using an anti-sense oligonucleotide approach. RESULTS: Over-expression of SAA3 led to a 4-fold increase in atherosclerosis lesion area compared to control mice (p = 0.01). Suppression of SAA3 decreased atherosclerosis in mice genetically deficient in SAA1.1 and SAA2.1 (p < 0.0001). CONCLUSIONS: SAA3 augments atherosclerosis in mice. Our results resolve a previous paradox in the literature and support extensive epidemiological data that SAA is pro-atherogenic.

Elevated circulating TGF-ß is not the cause of increased atherosclerosis development in biglycan deficient mice.

BACKGROUND AND AIMS: Vascular biglycan contributes to atherosclerosis development and increased biglycan expression correlates with increased atherosclerosis. However, mice deficient in biglycan have either no reduction in atherosclerosis or an unexpected increase in atherosclerosis. Biglycan deficient mice have systemically elevated TGF-ß, likely due to lack of sequestration of TGF-ß in the extracellular matrix. The purpose of this study was to determine if prevention of TGF-ß elevations in biglycan deficient mice affected atherosclerosis development. METHODS: Biglycan deficient mice were crossed to Ldlr deficient mice. Diabetes was induced via streptozotocin and all mice were fed a high cholesterol diet. Diabetic biglycan wild type and biglycan deficient Ldlr deficient mice were injected with the TGF-ß neutralizing antibody 1D11 or the irrelevant control antibody 13C4. RESULTS: Biglycan deficient mice had significantly elevated plasma TGF-ß levels, which was further increased by diabetes, and significantly increased atherosclerosis. There was a significant correlation between TGF-ß concentrations and atherosclerosis. However, despite nearly complete suppression of plasma TGF-ß levels in mice treated with the TGF-ß neutralizing antibody 1D11, there was no significant difference in atherosclerosis between mice with elevated TGF-ß levels and mice with suppressed TGF-ß levels. CONCLUSIONS: The increased atherosclerosis in biglycan deficient mice does not appear to be due to elevations in TGF-ß.

Prevention of renal apoB retention is protective against diabetic nephropathy: role of TGF-ß inhibition.

Animal studies demonstrate that hyperlipidemia and renal lipid accumulation contribute to the pathogenesis of diabetic nephropathy (DN). We previously demonstrated that renal lipoproteins colocalize with biglycan, a renal proteoglycan. The purpose of this study was to determine whether prevention of renal lipid (apoB) accumulation attenuates DN. Biglycan-deficient and biglycan wild-type Ldlr-/- mice were made diabetic via streptozotocin and fed a high cholesterol diet. As biglycan deficiency is associated with elevated transforming growth factor-ß (TGF-ß), in some experiments mice were injected with either the TGF-ß-neutralizing antibody, 1D11, or with 13C4, an irrelevant control antibody. Biglycan deficiency had no significant effect on renal apoB accumulation, but led to modest attenuation of DN with ∼30% reduction in albuminuria; however, biglycan deficiency caused a striking elevation in TGF-ß. Use of 1D11 led to sustained suppression of TGF-ß for approximately 8 weeks at a time. The 1D11 treatment caused decreased renal apoB accumulation, decreased albuminuria, decreased renal hypertrophy, and improved survival, compared with the 13C4 treatment. Thus, prevention of renal apoB accumulation is protective against development of DN. Furthermore, this study demonstrates that prevention of renal apoB accumulation is a mechanism by which TGF-ß inhibition is nephroprotective.

Pediatric Oral/Maxillofacial Soft Tissue Sarcomas: A Clinicopathologic Report of Four Cases.

Pediatric soft tissue sarcomas of the oral/maxillofacial region are rare neoplasms that present significant difficulty with respect to treatment and local control measures. We report four cases of pediatric oral/maxillofacial soft tissue sarcomas from our tertiary care pediatric hospital and emphasize the rarity of these malignancies and the challenges encountered in treating these lesions, and suggest areas for further research. We conclude that multimodal therapy and interdisciplinary cooperation are paramount to successful management of these lesions.

A brief elevation of serum amyloid A is sufficient to increase atherosclerosis.

Serum amyloid A (SAA) has a number of proatherogenic effects including induction of vascular proteoglycans. Chronically elevated SAA was recently shown to increase atherosclerosis in mice. The purpose of this study was to determine whether a brief increase in SAA similarly increased atherosclerosis in a murine model. The recombination activating gene 1-deficient (rag1(-/-)) × apolipoprotein E-deficient (apoe(-/-)) and apoe(-/-) male mice were injected, multiple times or just once respectively, with an adenoviral vector encoding human SAA1 (ad-SAA); the injected mice and controls were maintained on chow for 12-16 weeks. Mice receiving multiple injections of ad-SAA, in which SAA elevation was sustained, had increased atherosclerosis compared with controls. Strikingly, mice receiving only a single injection of ad-SAA, in which SAA was only briefly elevated, also had increased atherosclerosis compared with controls. Using in vitro studies, we demonstrate that SAA treatment leads to increased LDL retention, and that prevention of transforming growth factor beta (TGF-ß) signaling prevents SAA-induced increases in LDL retention and SAA-induced increases in vascular biglycan content. We propose that SAA increases atherosclerosis development via induction of TGF-ß, increased vascular biglycan content, and increased LDL retention. These data suggest that even short-term inflammation with concomitant increase in SAA may increase the risk of developing CVD.

Biglycan deficiency: increased aortic aneurysm formation and lack of atheroprotection.

Proteoglycans of the arterial wall play a critical role in vascular integrity and the development of atherosclerosis owing to their ability to organize extracellular matrix molecules and to bind and retain atherogenic apolipoprotein (apo)-B containing lipoproteins. Prior studies have suggested a role for biglycan in aneurysms and in atherosclerosis. Angiotensin II (angII) infusions into mice have been shown to induce abdominal aortic aneurysm development, increase vascular biglycan content, increase arterial retention of lipoproteins, and accelerate atherosclerosis. The goal of this study was to determine the role of biglycan in angII-induced vascular diseases. Biglycan-deficient or biglycan wildtype mice crossed to LDL receptor deficient (Ldlr-/-) mice (C57BL/6 background) were infused with angII (500 or 1000ng/kg/min) or saline for 28days while fed on normal chow, then pumps were removed, and mice were switched to an atherogenic Western diet for 6weeks. During angII infusions, biglycan-deficient mice developed abdominal aortic aneurysms, unusual descending thoracic aneurysms, and a striking mortality caused by aortic rupture (76% for males and 48% for females at angII 1000ng/kg/min). Histological analyses of non-aneurysmal aortic segments from biglycan-deficient mice revealed a deficiency of dense collagen fibers and the aneurysms demonstrated conspicuous elastin breaks. AngII infusion increased subsequent atherosclerotic lesion development in both biglycan-deficient and biglycan wildtype mice. However, the biglycan genotype did not affect the atherosclerotic lesion area induced by the Western diet after treatment with angII. Biglycan-deficient mice exhibited significantly increased vascular perlecan content compared to biglycan wildtype mice. Analyses of the atherosclerotic lesions demonstrated that vascular perlecan co-localized with apoB, suggesting that increased perlecan compensated for biglycan deficiency in terms of lipoprotein retention. Biglycan deficiency increases aortic aneurysm development and is not protective against the development of atherosclerosis. Biglycan deficiency leads to loosely packed aortic collagen fibers, increased susceptibility of aortic elastin fibers to angII-induced stress, and up-regulation of vascular perlecan content.

Increased atherosclerosis in mice with increased vascular biglycan content.

OBJECTIVE: The response to retention hypothesis of atherogenesis proposes that atherosclerosis is initiated via the retention of atherogenic lipoproteins by vascular proteoglycans. Co-localization studies suggest that of all the vascular proteoglycans, biglycan is the one most closely co-localized with LDL. The goal of this study was to determine if over-expression of biglycan in hyperlipidemic mice would increase atherosclerosis development. METHODS: Transgenic mice were developed by expressing biglycan under control of the smooth muscle actin promoter, and were crossed to the LDL receptor deficient (C57BL/6 background) atherosclerotic mouse model. Biglycan transgenic and non-transgenic control mice were fed an atherogenic Western diet for 4-12 weeks. RESULTS: LDL receptor deficient mice overexpressing biglycan under control of the smooth muscle alpha actin promoter had increased atherosclerosis development that correlated with vascular biglycan content. CONCLUSION: Increased vascular biglycan content predisposes to increased lipid retention and increased atherosclerosis development.

Deficiency of endogenous acute phase serum amyloid A does not affect atherosclerotic lesions in apolipoprotein E-deficient mice.

OBJECTIVE: Although elevated plasma concentrations of serum amyloid A (SAA) are associated strongly with increased risk for atherosclerotic cardiovascular disease in humans, the role of SAA in the pathogenesis of lesion formation remains obscure. Our goal was to determine the impact of SAA deficiency on atherosclerosis in hypercholesterolemic mice. APPROACH AND RESULTS: Apolipoprotein E-deficient (apoE(-/-)) mice, either wild type or deficient in both major acute phase SAA isoforms, SAA1.1 and SAA2.1, were fed a normal rodent diet for 50 weeks. Female mice, but not male apoE-/- mice deficient in SAA1.1 and SAA2.1, had a modest increase (22%; P≤0.05) in plasma cholesterol concentrations and a 53% increase in adipose mass compared with apoE-/- mice expressing SAA1.1 and SAA2.1 that did not affect the plasma cytokine levels or the expression of adipose tissue inflammatory markers. SAA deficiency did not affect lipoprotein cholesterol distributions or plasma triglyceride concentrations in either male or female mice. Atherosclerotic lesion areas measured on the intimal surfaces of the arch, thoracic, and abdominal regions were not significantly different between apoE-/- mice deficient in SAA1.1 and SAA2.1 and apoE-/- mice expressing SAA1.1 and SAA2.1 in either sex. To accelerate lesion formation, mice were fed a Western diet for 12 weeks. SAA deficiency had effect neither on diet-induced alterations in plasma cholesterol, triglyceride, or cytokine concentrations nor on aortic atherosclerotic lesion areas in either male or female mice. In addition, SAA deficiency in male mice had no effect on lesion areas or macrophage accumulation in the aortic roots. CONCLUSIONS: The absence of endogenous SAA1.1 and 2.1 does not affect atherosclerotic lipid deposition in apolipoprotein E-deficient mice fed either normal or Western diets.

Anti-D immunoglobulin therapy for pediatric ITP: before and after the FDA's black box warning.

In March 2010, the Food and Drug Administration (FDA) issued a black box warning for anti-D immunoglobulin (anti-D), an approved treatment for immune thrombocytopenia (ITP). It is unknown if and how clinical practice at U.S children's hospitals has since changed. We sought to describe inpatient anti-D usage, laboratory monitoring, and anti-D complications before and after the FDA warning. Using the Pediatric Health Information System, we collected data from 41 children's hospitals. There was a modest but statistically significant decrease in anti-D usage from pre-warning to post-warning. Severe complication rates were very low and did not change appreciably.

Prevention of TGFß induction attenuates angII-stimulated vascular biglycan and atherosclerosis in Ldlr-/- mice.

Angiotensin II (angII) accelerates atherosclerosis, but the mechanisms are not fully understood. The aim of this study was to determine whether TGFß is required for angII-induced atherosclerosis. Ldlr-null mice fed a normal chow diet were infused with angII or saline for 28 days. A single injection of TGFß neutralizing antibody 1D11 (2 mg/kg) prevented angII-induction of TGFß1 levels, and strikingly attenuated angII-induced accumulation of aortic biglycan content. To study atherosclerosis, mice were infused with angII or saline for 4 weeks, and then fed Western diet for a further 6 weeks. 1D11 had no effect on systolic blood pressure or plasma cholesterol; however, angII-infused mice that received 1D11 had reduced atherosclerotic lesion area by 30% (P < 0.05). Immunohistochemical analyses demonstrated that angII induced both lipid retention and accumulation of biglycan and perlecan which colocalized with apoB. 1D11 strikingly reduced the effect of angII on biglycan but not perlecan. 1D11 decreased total collagen content (P < 0.05) in the lesion area without changing plaque inflammation markers (CD68 and CD45). Thus, this study demonstrates that neutralization of TGFß attenuated angII stimulation of biglycan accumulation and atherogenesis in mice, suggesting that TGFß-mediated biglycan induction is one of the mechanisms underlying angII-promoted atherosclerosis.

Decreased body fat, elevated plasma transforming growth factor-ß levels, and impaired BMP4-like signaling in biglycan-deficient mice.

Biglycan (BGN), a small leucine-rich proteoglycan, binds the pro-fibrotic cytokine transforming growth factor ß (TGFß) and inhibits its bioactivity in vitro. Nevertheless, it is controversial whether BGN plays an inhibitory role in vivo. Therefore, the purpose of this study was to evaluate the effect of BGN deficiency on TGFß activity in vivo by studying 1-year-old Bgn null and wild-type (WT) mice on an Ldlr-null background. Phenotypic and metabolic characterization showed that the Bgn null mice had lower body weight, shorter body length, and shorter femur length (all p < 0.05). Surprisingly, the Bgn null mice also exhibited a striking reduction in percent body fat compared to WT mice (p == 0.006), but no changes were observed in plasma triglycerides, total cholesterol, or glycohemoglobin. Both total and bioactive TGFß1 concentrations in plasma were markedly elevated in Bgn null mice compared to WT mice (4-fold and 11-fold increase, respectively, both p < 0.001), but no changes were found in hepatic levels of mRNA for Tgfß1 or its receptors. Bgn null mice exhibited elevated expression of hepatic fibronectin protein (p = 0.034) without changes in hepatic or renal histology, and Bgn null mice had decreased urinary albumin/creatinine ratio (p = 0.01). Two key downstream targets of bone morphogenetic protein 4-like signaling, SMAD1/3/5 phosphorylation and Id2 gene expression, were found dramatically reduced in Bgn null livers (p = 0.034). Thus, BGN deficiency decreases body fat in this hyperlipidemic mouse model without changing liver or kidney histology. Overall, we propose that this unexpected phenotype arises from the effects of BGN deficiency in vivo to elevate TGFß levels while decreasing bone morphogenetic protein 4-like signaling.

Serum amyloid A, but not C-reactive protein, stimulates vascular proteoglycan synthesis in a pro-atherogenic manner.

Inflammatory markers serum amyloid A (SAA) and C-reactive protein (CRP) are predictive of cardiac disease and are proposed to play causal roles in the development of atherosclerosis, in which the retention of lipoproteins by vascular wall proteoglycans is critical. The purpose of this study was to determine whether SAA and/or CRP alters vascular proteoglycan synthesis and lipoprotein retention in a pro-atherogenic manner. Vascular smooth muscle cells were stimulated with either SAA or CRP (1 to 100 mg/L) and proteoglycans were then isolated and characterized. SAA, but not CRP, increased proteoglycan sulfate incorporation by 50 to 100% in a dose-dependent manner (P < 0.0001), increased glycosaminoglycan chain length, and increased low-density lipoprotein (LDL) binding affinity (K(d), 29 microg/ml LDL versus 90 microg/ml LDL for SAA versus control proteoglycans; P < 0.005). Furthermore, SAA up-regulated biglycan via the induction of endogenous transforming growth factor (TGF)-beta. To determine whether SAA stimulated proteoglycan synthesis in vivo, ApoE(-/-) mice were injected with an adenovirus expressing human SAA-1, a null virus, or saline. Mice that received adenovirus expressing SAA had increased TGF-beta concentrations in plasma and increased aortic biglycan content compared with mice that received either null virus or saline. Thus, SAA alters vascular proteoglycans in a pro-atherogenic manner via the stimulation of TGF-beta and may play a causal role in the development of atherosclerosis.

Angiotensin II increases vascular proteoglycan content preceding and contributing to atherosclerosis development.

Angiotensin II (angII) is known to promote atherosclerosis; however, the mechanisms involved are not fully understood. To determine whether angII stimulates proteoglycan production and LDL retention, LDL receptor-deficient mice were infused with angII (1,000 ng/kg/min) or saline via osmotic minipumps. To control for the hypertensive effect of angII, a parallel group received norepinephrine (NE; 5.6 mg/kg/day). Arterial lipid accumulation was evaluated by measuring the retention rate of LDL in isolated carotid arteries perfused ex vivo. Mice infused with angII had increased vascular content of biglycan and perlecan and retained twice as much LDL as saline- or NE-infused mice, although no group developed atherosclerosis at this time. To determine whether this increase in biglycan and perlecan content predisposed to atherosclerosis development, mice were infused with angII, saline, or NE for 4 weeks, then pumps were removed and mice received an atherogenic Western diet for another 6 weeks. Mice that had received angII infusions had 3-fold increased atherosclerosis compared with mice that had received saline or NE, and apolipoprotein B colocalized with both proteoglycans. Thus, one mechanism by which angII promotes atherosclerosis is increased proteoglycan synthesis and increased arterial LDL retention, which precedes and contributes to atherosclerosis development.