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Burkitt lymphoma (BL) accounts for most pediatric non-Hodgkin lymphomas, being less common but significantly more lethal when diagnosed in adults. Much of the knowledge of the genetics of BL thus far has originated from the study of pediatric BL (pBL), leaving its relationship to adult BL (aBL) and other adult lymphomas not fully explored. We sought to more thoroughly identify the somatic changes that underlie lymphomagenesis in aBL and any molecular features that associate with clinical disparities within and between pBL and aBL. Through comprehensive whole-genome sequencing of 230 BL and 295 diffuse large B-cell lymphoma (DLBCL) tumors, we identified additional significantly mutated genes, including more genetic features that associate with tumor Epstein-Barr virus status, and unraveled new distinct subgroupings within BL and DLBCL with 3 predominantly comprising BLs: DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Each BL subgroup is characterized by combinations of common driver and noncoding mutations caused by aberrant somatic hypermutation. The largest subgroups of BL cases, IC-BL and DGG-BL, are further characterized by distinct biological and gene expression differences. IC-BL and DGG-BL and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among aBL and pBL cohorts. These findings highlight shared pathogenesis between aBL and pBL, and establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiologic, diagnostic, and therapeutic strategies.

Burkitt lymphoma (BL) accounts for the majority of pediatric non-Hodgkin lymphomas (NHL) and is relatively rare but significantly more lethal when diagnosed in adults. The global incidence is highest in Sub-Saharan Africa, where Epstein-Barr virus (EBV) positivity is observed in 95% of all tumors. Both pediatric (pBL) and adult (aBL) cases are known to share some driver mutations, for example MYC translocations, which are seen in > 90% of cases. Sequencing efforts have identified many common somatic alterations that cooperate with MYC in lymphomagenesis with approximately 30 significantly mutated genes (SMG) reported thus far. Recent analyses revealed non-coding mutation patterns in pBL that were attributed to aberrant somatic hypermutation (aSHM). We sought to identify genomic and molecular features that may explain clinical disparities within and between aBL and pBL in an effort to delineate BL subtypes that may allow for the stratification of patients with shared pathobiology. Through comprehensive sequencing of BL genomes, we found additional SMGs, including more genetic features that associate with tumor EBV status, and established three new genetic subgroups that span pBL and aBL. Direct comparisons between pBL and aBL revealed only marginal differences and the mutational profiles were consistently better explained by EBV status. Using an unsupervised clustering approach to identify subgroupings within BL and diffuse large B-cell lymphoma (DLBCL), we have defined three genetic subgroups that predominantly comprise BL tumors. Akin to the recently defined DLBCL subgroups, each BL subgroup is characterized by combinations of common driver mutations and non-coding mutations caused by aSHM. Two of these subgroups and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among the aBL and pBL cohorts. These findings highlight not only a shared pathogenesis between aBL and pBL, but also establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiological studies, and diagnostic and therapeutic strategies.

Mathematical models can provide insights into the control of pandemic COVID-19, which remains a global priority. The dynamics of directly-transmitted infectious diseases, such as COVID-19, are usually described by compartmental models where individuals are classified as susceptible, infected and removed. These SIR models typically assume homogenous transmission of infection, even in large populations, a simplification that is convenient but inconsistent with observations. Here we use original data on the dynamics of COVID-19 spread in a Brazilian city to investigate the structure of the transmission network. We find that transmission can be described by a network in which each infectious individual has a small number of susceptible contacts, of the order of 2-5, which is independent of total population size. Compared with standard models of homogenous mixing, this scale-free, fractal infection process gives a better description of COVID-19 dynamics through time. In addition, the contact process explains the geographically localized clusters of disease seen in this Brazilian city. Our scale-free model can help refine criteria for physical and social distancing in order to more effectively mitigate the spread of COVID-19. We propose that scale-free COVID-19 dynamics could be a widespread phenomenon, a topic for further investigation.

ObjectivesTo evaluate if antibodies induced by infection with a different SARS-CoV-2 virus strain neutralize the P.1 variant.MethodsConvalescent sera from 60 individuals following a documented SARS-CoV-2 infection were assayed for neutralizing antibody titer against both strains.ResultsFifty-six and 50 sera were positive for neutralizing antibodies against the ancestral and P.1 strains, respectively. Neutralization titers were higher against the ancestral strain, but in the majority of patients differences did not differ by more than a single dilution.ConclusionsNeutralizing antibodies that were generated following infection with SARS-CoV-2 B.1.1.28 were effective in vitro, against the SARS-CoV-2 P.1. variant.

BackgroundDespite most cases not requiring hospital care, there are limited community-based clinical data on COVID-19.MethodsThe Corona São Caetano programme is a primary care initiative providing care to all residents with COVID-19 in São Caetano do Sul, Brazil. It was designed to capture standardised clinical data on community COVID-19 cases. After triage of potentially severe cases, consecutive patients presenting to a multimedia screening platform between 13 April and 13 May 2020 were tested at home with SARS-CoV-2 reverse transcriptase (RT) PCR; positive patients were followed up for 14 days with phone calls every 2 days. RT-PCR-negative patients were offered additional SARS-CoV-2 serology testing to establish their infection status. We describe the clinical, virological and natural history features of this prospective population-based cohort.FindingsOf 2073 suspected COVID-19 cases, 1583 (76.4%) were tested by RT-PCR, of whom 444 (28.0%, 95% CI 25.9 to 30.3) were positive; 604/1136 (53%) RT-PCR-negative patients underwent serology, of whom 52 (8.6%) tested SARS-CoV-2 seropositive. The most common symptoms of confirmed COVID-19 were cough, fatigue, myalgia and headache; whereas self-reported fever (OR 3.0, 95% CI 2.4 to 3.9), anosmia (OR 3.3, 95% CI 2.6 to 4.4) and ageusia (OR 2.9, 95% CI 2.3 to 3.8) were most strongly associated with a positive COVID-19 diagnosis by RT-PCR or serology. RT-PCR cycle thresholds were lower in men, older patients, those with fever and arthralgia and closer to symptom onset. The rates of hospitalisation and death among 444 RT-PCR-positive cases were 6.7% and 0.7%, respectively, with older age and obesity more frequent in the hospitalised group.ConclusionCOVID-19 presents in a similar way to other mild community-acquired respiratory diseases, but the presence of fever, anosmia and ageusia can assist the specific diagnosis. Most patients recovered without requiring hospitalisation with a low fatality rate compared with other hospital-based studies.

SARS-CoV-2 quickly spread in the worldwide population by contact with oral and respiratory secretions of infected individuals, imposing social restrictions to control the infection. Massive testing is essential to breaking the chain of COVID-19 transmission. The aim of this study was to compare the performance of at-home self-collected samples - saliva and combined nasal-oropharyngeal swabs (NOP) - for SARS-CoV-2 detection in a telemedicine platform for COVID-19 surveillance. We analyzed 201 patients who met the criteria of suspected COVID-19. NOP sampling were combined (nostrils and oropharynx) and saliva collected using a cotton pad device. Detection of SARS-COV-2 was performed by using the Altona RealStar® SARS-CoV-2 RT-PCR Kit 1.0. According to our data, there was an overall significant agreement (κ coefficient value of 0.58) between the performances of saliva and NOP. Assuming that positive results in either sample represent true infections, 70 patients positive for SARS-CoV-2 were identified, with 52/70 being positive in NOP and 55/70 in saliva. This corresponds to sensitivities of 74.2% (95% CI; 63.7% to 83.1%) for NOP and 78.6% (95% CI; 67.6% to 86.6%) for saliva. We also found a strong correlation (β-coefficients < 1) between the cycle threshold values in saliva and NOP. Ageusia was the only symptom associated with patients SARS-CoV-2 positive only in NOP (p=0.028). In conclusion, our data show the feasibility of using at-home self-collected samples (especially saliva), as an adequate alternative for SARS-CoV-2 detection. This new approach of testing can be useful to develop strategies for COVID-19 surveillance and for guiding public health decisions.

In people living with HIV (PLWH), chronic inflammation can lead to cancer initiation and progression, besides driving a dysregulated and diminished immune responsiveness. HIV infection also leads to increased transcription of Human Endogenous Retroviruses (HERVs), which could increase an inflammatory environment and create a tumor growth suppressive environment with high expression of pro-inflammatory cytokines. In order to determine the impact of HIV infection to HERV expression on the breast cancer microenvironment, we sequenced total RNA from formalin-fixed paraffin-embedded (FFPE) breast cancer samples of women HIV-negative and HIV-positive for transcriptome and retrotranscriptome analyses. We performed RNA extraction from FFPE samples, library preparation and total RNA sequencing (RNA-seq). The RNA-seq analysis shows 185 differentially expressed genes: 181 host genes (178 upregulated and three downregulated) and four upregulated HERV transcripts in HIV-positive samples. We also explored the impact of HERV expression in its neighboring breast cancer development genes (BRCA1, CCND1, NBS1/NBN, RAD50, KRAS, PI3K/PIK3CA) and in long non-coding RNA expression (AC060780.1, also known as RP11-242D8.1). We found a significant positive association of HERV expression with RAD50 and with AC060780.1, which suggest a possible role of HERV in regulating breast cancer genes from PLWH with breast cancer. In addition, we found immune system, extracellular matrix organization and metabolic signaling genes upregulated in HIV-positive breast cancer. In conclusion, our findings provide evidence of transcriptional and retrotranscriptional changes in breast cancer from PLWH compared to non-HIV breast cancer, including dysregulation of HERVs, suggesting an indirect effect of the virus on the breast cancer microenvironment.

BackgroundDespite most cases not requiring hospital care, there are limited community-based clinical data on COVID-19.Methods and findingsThe Corona São Caetano program is a primary care initiative offering COVID-19 care to all residents of São Caetano do Sul, Brazil. After triage of potentially severe cases, consecutive patients presenting between 13th April and 13th May 2020 were tested at home with SARS-CoV-2 reverse transcriptase (RT) PCR; positive patients were followed up for 14 days. RT-PCR-negative patients were offered SARS-CoV-2 serology. We describe the clinical features, virology and natural history of this prospective population-based cohort. Of 2,073 suspected COVID-19 cases, 1,583 (76·4%) were tested by RT-PCR, of whom 444 (28·0%, 95%CI: 25·9% - 30·3%) were positive; 604/1,136 (53%) RT-PCR-negative patients underwent serology, of whom 52 (8·6%) tested SARS-CoV-2 seropositive. The most common symptoms of COVID-19 were cough, fatigue, myalgia and headache; whereas self-reported fever, anosmia, and ageusia were most associated with a positive COVID-19 diagnosis. RT-PCR cycle thresholds were lower in men, older patients, those with fever and arthralgia, and around symptom onset. The rates of hospitalization and death among 444 RT-PCR-positive cases were 6·7% and 0·7%, respectively, with older age and obesity more frequent in the hospitalized group.ConclusionsCOVID-19 presents similarly to other mild respiratory disease in primary care. Some symptoms assist the differential diagnosis. Most patients can be managed at home.

In diseases where epigenetic mechanisms are changed, such as cancer, many genes show altered gene expression and inhibited genes become activated. Human endogenous retrovirus type K (HERV-K) expression is usually inhibited in normal cells from healthy adults. In tumor cells, however, HERV-K mRNA expression has been frequently documented to increase. Importantly, HERV-K-derived proteins can act as tumor-specific antigens, a class of neoantigens, and induce immune responses in different types of cancer. In this review, we describe the function of the HERV-K HML-2 subtype in carcinogenesis as biomarkers, and their potential as targets for cancer immunotherapy.

Background It remains unclear whether COVID-19 is associated with psychiatric symptoms during or after the acute illness phase. Being affected by the disease exposes the individual to an uncertain prognosis and a state of quarantine. These factors can predispose individuals to the development of mental symptoms during or after the acute phase of the disease. There is a need for prospective studies assessing psychiatric symptoms in COVID-19 patients in the post-infection period. Methods In this prospective cohort study, nasopharyngeal swabs for COVID-19 tests were collected at patients' homes under the supervision of trained healthcare personnel. Patients who tested positive for COVID-19 and were classified as mild cases (N = 895) at treatment intake were further assessed for the presence of psychiatric symptoms (on average, 56.6 days after the intake). We investigated the association between the number of COVID-19 symptoms at intake and depressive, anxiety and post-traumatic symptoms approximately two months later, adjusting for previous mental health status, time between baseline and outcome, and other confounders. Multivariate logistic regression and generalized linear models were employed for categorical and continuous outcomes, respectively. Results A clinically significant level of depressive, anxiety and post-traumatic stress symptoms were reported by 26.2% (N = 235), 22.4% (N = 201), and 17.3% (N = 155) of the sample. Reporting an increased number of COVID-related symptoms was associated with the presence of clinically significant levels of depressive (aOR = 1.059;95%CI = 1.002–1.119), anxiety (aOR = 1.072;95%CI = 1.012–1.134), and post-traumatic stress (aOR = 1.092;95%CI = 1.024–1.166) symptoms. Sensitivity analyses supported findings for both continuous and categorical measures. Conclusion Exposure to an increased number of COVID-19 symptoms may be associated with depressive, anxiety and post-traumatic symptoms after the acute phase of the disease. These patients should be monitored for the development of psychiatric symptoms after COVID-19 treatment discharge. Early interventions, such as brief interventions of psychoeducation on coping strategies, could benefit these individuals.

Introduction: Burkitt lymphoma (BL) accounts for approximately 50% of all pediatric non-Hodgkin lymphomas compared to 1-2% in adults. Adult BL (aBL) remains a poorly understood entity and its relationship to pediatric BL (pBL) and to DLBCL has not been fully elucidated. The variable treatment outcomes between these entities necessitate a more thorough understanding of the genetic and molecular features underlying their biology to enable better prognostication and more effective treatments. We sought to comprehensively determine genetic features shared with DLBCL and those that are unique to BL, to further delineate genetic subgroupings within each entity. Methods: Samples for this study were collected through the Burkitt Lymphoma Genome Sequencing Project (BLGSP). We sequenced the tumor genomes of 139 pBL and 92 aBL, consisting of both EBV-positive (EBV+) and EBV-negative (EBV-) BLs, and compared these to the genomes of 252 DLBCL patients. All cases were analyzed for simple somatic mutations (SSM), recurrent copy number variations (CNV), structural variations (SV), aberrant somatic hypermutation (aSHM), and SSM hotspots. Mutations were used as features for the identification of genetic subgroups using non-negative matrix factorization (NMF) clustering. Results: Clustering of BL and DLBCL revealed six distinct genetic subgroups (Figure 1) with three primarily representing DLBCLs (DLBCL-1, DLBCL-2, and DLBCL-3) and three predominantly comprising BLs (M53-BL, IC-BL, and DGG-BL). The DLBCL-predominant subgroups partially overlapped with those previously described and resembled features of EZB and ST2-like subgroups. The frequency of aBLs within these subgroups was higher than that of pBL patients (p=0.0005). The new cluster M53-BL consists of both pBL (9/27) and aBL (13/27) samples and is characterized by the highest prevalence of mutations in TP53 accompanied by the paucity of other driver mutations but without the aneuploidy associated with the A53 subgroup described in DLBCL. Enrichment of EBV- samples in this cluster further corroborate our previous findings of TP53 mutations being associated with EBV- BL. IC-BL is characterized by mutations in ID3, CCND3, and SMARCA4. In contrast, DGG-BL, where 65% of the cluster consisted of EBV+ BL samples, had mutations in DDX3X, GNA13, and GNAI2. Using a linear model, we compared the rates of aSHM in BL genomes from all clusters and identified the DLBCL-3 cluster to harbor the highest aSHM rates at common sites while the M53-BL cluster harbored the lowest rates. To further establish the biological basis of unique clusters within BL, we conducted differential gene expression analyses between the two major BL genetic subgroups, DGG-BL and IC-BL. We identified a total of 86 differentially expressed genes between the two clusters (p.adj < 0.01 and |log2foldChange| > 1). Among the genes with the strongest differential expression were IRF4, SERPINA9, and TNFRSF13B. Each of these are notable as their expression is a component of the DLBCL cell-of-origin and double-hit signature classifiers. Further, we found IRF4 expression to be one of the strongest predictors of cluster membership, with high IRF4 expression associated with IC-BL membership. Using TP53 and ID3 mutations as a proxy for M53-BL and IC-BL clusters in aBL, we found mutations in TP53 to be associated with significantly inferior progression free survival (PFS) at 2 year follow up, while mutations in ID3 were associated with overall better PFS at 2 year follow up. Conclusion: This work identifies novel genetic subgroups within BL with characteristic genetic and gene expression differences and some bearing relationship to DLBCL subgroups. The three subgroups with predominantly BL samples (DGG-BL, IC-BL, and M53-BL) each comprised a mixture of aBL and pBL samples, confirming similar molecular features in these entities. The IC-BL cluster is associated with mutations in ID3 and CCND3, high IRF4 expression, and ID3 mutated cases exhibited significantly better outcomes. M53-BL is associated with TP53 mutations and inferior PFS in aBL, representing a subset of patients to be considered for novel treatment approaches. These findings highlight shared pathogenesis between aBL and pBL and establish genetic subtypes within BL that delineate cases with distinct molecular and clinical features. This provides a new framework for new diagnostic and therapeutic strategies. Figure 1 Figure 1. Disclosures Abramson: Seagen Inc.: Research Funding; Allogene Therapeutics: Consultancy; Astra-Zeneca: Consultancy; Incyte Corporation: Consultancy; BeiGene: Consultancy; Kymera: Consultancy; Kite Pharma: Consultancy; Novartis: Consultancy; Bluebird Bio: Consultancy; C4 Therapeutics: Consultancy; Morphosys: Consultancy; Genmab: Consultancy; EMD Serono: Consultancy; Bristol-Myers Squibb Company: Consultancy, Research Funding; AbbVie: Consultancy; Karyopharm: Consultancy; Genentech: Consultancy. Bartlett: Pharmacyclics: Research Funding; Millennium: Research Funding; Merck: Research Funding; Kite, a Gilead Company: Research Funding; Janssen: Research Funding; Genentech: Research Funding; Forty Seven: Research Funding; Celgene: Research Funding; Bristol Myers Squibb: Research Funding; Autolus: Research Funding; Seagen: Consultancy, Research Funding; Roche/Genentech: Consultancy; ADC Therapeutics: Consultancy, Research Funding. Casper: EUSA Pharma: Consultancy. Gerrie: Roche: Research Funding; AbbVie: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Astrazeneca: Honoraria, Research Funding; Sandoz: Honoraria. Grande: Sage Bionetworks: Current Employment. Mullighan: Illumina: Membership on an entity's Board of Directors or advisory committees; Pfizer: Research Funding; AbbVie: Research Funding; Amgen: Current equity holder in publicly-traded company. Noy: Epizyme: Consultancy; Rafael Parhma: Research Funding; Morphosys: Consultancy; Targeted Oncology: Consultancy; Medscape: Consultancy; Pharmacyclics: Consultancy, Research Funding; Janssen: Consultancy, Honoraria. Scott: NanoString Technologies: Patents & Royalties: Patent describing measuring the proliferation signature in MCL using gene expression profiling.; AstraZeneca: Consultancy; Abbvie: Consultancy; Celgene: Consultancy; Incyte: Consultancy; Janssen: Consultancy, Research Funding; Rich/Genentech: Research Funding; BC Cancer: Patents & Royalties: Patent describing assigning DLBCL COO by gene expression profiling--licensed to NanoString Technologies. Patent describing measuring the proliferation signature in MCL using gene expression profiling. . Morin: Foundation for Burkitt Lymphoma Research: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy; Epizyme: Patents & Royalties.

Torquetenovirus (TTV) is present in biological fluids from healthy individuals and measurement of its titer is used to assess immune status in individuals with chronic infections and after transplants. We assessed if the titer of TTV in saliva varied with the presence of SARS-CoV-2 in the nasopharynx and could be a marker of COVID-19 status. Saliva from 91 individuals positive for SARS-CoV-2 in nasal-oropharyngeal samples, and from 126 individuals who were SARS-CoV-2-negative, all with mild respiratory symptoms, were analyzed. Both groups were similar in age, gender, symptom duration and time after symptom initiation when saliva was collected. Titers of TTV and SARS-CoV-2 were assessed by gene amplification. Loss of smell (p = 0.0001) and fever (p = 0.0186) were more prevalent in SARS-CoV-2-positive individuals, while sore throat (p = 0.0001), fatigue (p = 0.0037) and diarrhea (p = 0.0475) were more frequent in the SARS-CoV-2 negative group. The saliva TTV and nasal-oropharyngeal SARS-CoV-2 titers were correlated (p = 0.0085). The TTV level decreased as symptoms resolved in the SARS-CoV-2 infected group (p = 0.0285) but remained unchanged in the SARS-CoV-2 negative controls. In SARS-CoV-2 positive subjects who provided 2–4 saliva samples and in which TTV was initially present, the TTV titer always decreased over time as symptoms resolved. We propose that sequential TTV measurement in saliva is potentially useful to assess the likelihood of symptom resolution in SARS-CoV-2-positive individuals and to predict prognosis.

Rapid diagnostics is pivotal to curb SARS-CoV-2 transmission, and saliva has emerged as a practical alternative to naso/oropharyngeal (NOP) specimens. We aimed to develop a direct RT-LAMP (reverse transcription loop-mediated isothermal amplification) workflow for viral detection in saliva, and to provide more information regarding its potential in curbing COVID-19 transmission. Clinical and contrived specimens were used to optimize formulations and sample processing protocols. Salivary viral load was determined in symptomatic patients to evaluate the clinical performance of the test and to characterize saliva based on age, gender and time from onset of symptoms. Our workflow achieved an overall sensitivity of 77.2% (n = 90), with 93.2% sensitivity, 97% specificity, and 0.895 Kappa for specimens containing &gt, 102 copies/μL (n = 77). Further analyses in saliva showed that viral load peaks in the first days of symptoms and decreases afterwards, and that viral load is ~10 times lower in females compared to males, and declines following symptom onset. NOP RT-PCR data did not yield relevant associations. This work suggests that saliva reflects the transmission dynamics better than NOP specimens, and reveals gender differences that may reflect higher transmission by males. This saliva RT-LAMP workflow can be applied to track viral spread and, to maximize detection, testing should be performed immediately after symptoms are presented, especially in females.

Although generally curable with intensive chemotherapy in resource-rich settings, Burkitt lymphoma (BL) remains a deadly disease in older patients and in sub-Saharan Africa. Epstein-Barr virus (EBV) positivity is a feature in more than 90% of cases in malaria-endemic regions, and up to 30% elsewhere. However, the molecular features of BL have not been comprehensively evaluated when taking into account tumor EBV status or geographic origin. Through an integrative analysis of whole-genome and transcriptome data, we show a striking genome-wide increase in aberrant somatic hypermutation in EBV-positive tumors, supporting a link between EBV and activation-induced cytidine deaminase (AICDA) activity. In addition to identifying novel candidate BL genes such as SIN3A, USP7, and CHD8, we demonstrate that EBV-positive tumors had significantly fewer driver mutations, especially among genes with roles in apoptosis. We also found immunoglobulin variable region genes that were disproportionally used to encode clonal B-cell receptors (BCRs) in the tumors. These include IGHV4-34, known to produce autoreactive antibodies, and IGKV3-20, a feature described in other B-cell malignancies but not yet in BL. Our results suggest that tumor EBV status defines a specific BL phenotype irrespective of geographic origin, with particular molecular properties and distinct pathogenic mechanisms. The novel mutation patterns identified here imply rational use of DNA-damaging chemotherapy in some patients with BL and targeted agents such as the CDK4/6 inhibitor palbociclib in others, whereas the importance of BCR signaling in BL strengthens the potential benefit of inhibitors for PI3K, Syk, and Src family kinases among these patients.

Disseminated infection by Fusarium is a rare, frequently lethal condition in severely immunocompromised patients, including bone marrow transplant recipients. However, autologous bone marrow transplant recipients are not expected to be at high risk to develop fusariosis. We report a rare case of lethal disseminated Fusarium infection in an autologous bone marrow transplant recipient during pre-engraftment phase. Keywords: Stem cell transplant, Autologous, Fusarium

Background: The outbreak of Zika virus (ZIKV) infection in Brazil has raised concerns that infection during pregnancy could cause microcephaly and other severe neurodevelopmental malformations in the fetus. The mechanisms by which ZIKV causes fetal abnormalities are largely unknown. The importance of pre-infection with dengue virus (DENV), or other flaviviruses endemic to Brazil, remains to be investigated. It has been reported that antibodies directed against DENV can increase ZIKV infectivity by antibody dependent enhancement (ADE), suggesting that a history of prior DENV infection might worsen the outcome of ZIKV infection.Methods: We used bioinformatics tools to design 18 peptides from the ZIKV envelope containing predicted HLA-I T-cell epitopes and investigated T-cell cross-reactivity between ZIKV-infected individuals and DENV-vaccinated subjects by IFNg ELISPOT.Results: Three peptides induced IFNg production in both ZIKV-infected subjects and in DENV-vaccinated individuals. Flow cytometry indicated that 1 ZIKV peptide induced a CD4+ T-cell response in DENV-vaccinated subjects.Conclusions: We demonstrated that vaccination against DENV induced a T-cell response against ZIKV and identified one such CD4+ T-cell epitope. The ZIKV-reactive CD4+ T cells induced by DENV vaccination and identified in this study could contribute to the appearance of cross-reactive antibodies mediating ADE.

Now in its 4th decade, the burden of HIV disease still persists despite significant milestone achievements in HIV prevention, diagnosis, treatment, care, and support. Even with long-term use of currently available antiretroviral therapies (ART), eradication of HIV remains elusive and now poses a unique set of challenges for the HIV infected individual. The occurrence of HIV-associated non-AIDS related co-morbidities outside the scope of AIDS defining illnesses, in particular Non-AIDS defining cancers (NADC), are much greater than the age matched uninfected population. The underlying mechanism is now recognized to be in part related to the immune dysregulated and inflammatory status characteristic of HIV infection that persist despite ART. Natural Killer (NK) cells are multifunctional effector immune cells that play a critical role in shaping the innate immune responses to viral infections and cancer. NK cells can modulate the adaptive immune response via their role in dendritic cell (DC) maturation, removal of immature tolerogenic DCs, and their ability to produce immunoregulatory cytokines. NK cells are therefore poised as attractive therapeutic targets that can be harnessed to control or clear both HIV and HIV-associated malignancies. To date, features of the tumor microenvironment and the evolution of NK-cell function among individuals with HIV-related malignancies remain unclear and may be distinct from malignancies observed in uninfected persons. This review intends to uncouple anti-HIV and anti-tumor NK-cell features that can be manipulated to halt the evolution of HIV disease and HIV-associated malignancies and serve as potential preventative and curative immunotherapeutic options.

Human T-cell lymphotropic virus (HTLV)-1 was the first human retrovirus to be associated to cancer, namely adult T-cell leukemia (ATL), but its pathogenesis remains enigmatic, since only a minority of infected individuals develops either ATL or the neuroinflammatory disorder HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A functional FAS -670 polymorphism in an interferon (IFN)-regulated STAT1-binding site has been associated to both ATL and HAM/TSP susceptibility. Fashi T stem cell memory (Tscm) cells have been identified as the hierarchical apex of ATL, but have not been investigated in HAM/TSP. In addition, both FAS and STAT1 have been identified in an IFN-inducible HAM/TSP gene signature, but its pathobiological significance remains unclear. We comprehensively explored Fas expression (protein/mRNA) and function in lymphocyte activation, apoptosis, proliferation, and transcriptome, in PBMC from a total of 47 HAM/TSP patients, 40 asymptomatic HTLV-1-infected individuals (AC), and 58 HTLV-1 -uninfected healthy controls. Fas surface expression followed a two-step increase from HC to AC and from AC to HAM/TSP. In HAM/TSP, Fas levels correlated positively to lymphocyte activation markers, but negatively to age of onset, linking Fashi cells to earlier, more aggressive disease. Surprisingly, increased lymphocyte Fas expression in HAM/TSP was linked to decreased apoptosis and increased lymphoproliferation upon in vitro culture, but not to proviral load. This Fashi phenotype is HAM/TSP-specific, since both ex vivo and in vitro Fas expression was increased as compared to multiple sclerosis (MS), another neuroinflammatory disorder. To elucidate the molecular mechanism underlying non-apoptotic Fas signaling in HAM/TSP, we combined transcriptome analysis with functional assays, i.e., blocking vs. triggering Fas receptor in vitro with antagonist and agonist-, anti-Fas mAb, respectively. Treatment with agonist anti-Fas mAb restored apoptosis, indicating biased, but not defective Fas signaling in HAM/TSP. In silico analysis revealed biased Fas signaling toward proliferation and inflammation, driven by RelA/NF-κB. Correlation of Fas transcript levels with proliferation (but not apoptosis) was confirmed in HAM/TSP ex vivo transcriptomes. In conclusion, we demonstrated a two-step increase in Fas expression, revealing a unique Fashi lymphocyte phenotype in HAM/TSP, distinguishable from MS. Non-apoptotic Fas signaling might fuel HAM/TSP pathogenesis, through increased lymphoproliferation, inflammation, and early age of onset. ispartof: Frontiers in Immunology vol:8 issue:FEB pages:97-97 ispartof: location:Switzerland status: published

HIV-1 latency is a major obstacle to HIV-1 eradication. Coinfection with HTLV-1 has been associated with faster progression to AIDS. HTLV-1 encodes the transactivator Tax which can activate both HTLV-1 and HIV-1 transcription. Here, we demonstrate that Tax activates HIV transcription in latent CD4+ T cells. Tax promotes the activation of P-TEFb, releasing CDK9 and Cyclin T1 from inactive forms, promoting transcription elongation and reactivation of latent HIV-1. Tax mutants lacking interaction with the HIV-1-LTR promoter were not able to activate P-TEFb, with no subsequent activation of latent HIV. In HIV-infected primary resting CD4+ T cells, Tax-1 reactivated HIV-1 transcription up to five fold, confirming these findings in an ex vivo latency model. Finally, our results confirms that HTLV-1/Tax hijacks cellular partners, promoting HIV-1 transcription, and this interaction should be further investigated in HIV-1 latency studies in patients with HIV/HTLV-1 co-infection.

Fever of unknown origin (FUO), defined as a temperature higher than 38.3°C on several occasions and lasting longer than three weeks that is associated with a diagnosis that remains uncertain after one week of investigation (1), is a frequent condition in the infectious diseases specialty clinic. The condition is often associated with extensive diagnostic procedures and, not rarely, frustration for both the patient and the physician. An evidence-based approach has been used to group the causes of FUO (2) into four general categories: infectious, rheumatic/inflammatory, neoplastic, and miscellaneous disorders (3). Infectious diseases such as endocarditis, intra-abdominal abscesses, and tuberculosis, as well as inflammatory conditions such as temporal arteritis, adult's Still disease, and late-onset rheumatoid arthritis, are commonly identified causes of FUO (3). However, unexpected and rare causes are sometimes diagnosed, as reported below in a case of sclerosing mesenteritis.

HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develop HAM/TSP. The cellular immune response has been implicated in the development of inflammatory alterations in these patients; however the pathogenic mechanisms for disease progression remain unclear. Furthermore, HTLV-1-infected individuals have an increase incidence of Mycobacterium tuberculosis (Mtb) infection, suggesting that immunological defect are associated with HTLV-1 infection. Evidence suggests an important role for Mucosal-associated invariant T (MAIT) cells in the early control of Mtb infection. Chronic viral infections like HIV and HCV have been associated with decreased frequency and functionality of MAIT cells. We hypothesized that HTLV-1 infection is associated with similar perturbations in MAIT cells. We investigated MAIT cell frequency, phenotype, and function by flow cytometry in a cohort of 10 asymptomatic and 10 HAM/TSP HTLV-1 infected patients. We found that MAIT cells from HTLV-1-infected subjects were reduced and showed high co-expression of the activation markers CD38 and HLA-DR but normal levels of CCR6 and CD127. MAIT cells had a lower expression of the transcription factor PLZF in HAM/TSP patients. Unlike Tax-specific CD8+T cells, which are hyperfunctional, MAIT cells from HTLV-1-infected subjects had a poor IFNγ response following antigen stimulation. MAIT cell perturbations in HTLV-1 infection were not associated with HTLV-1 proviral load and MAIT cells were not infected by HTLV-1 in vivo. Rather, MAIT cells loss was associated with immune activation. Overall, our results do not support a role for MAIT cells in HAM/TSP pathogenesis but reduced numbers of MAIT cells, together with their poor functionality, could contribute to the increased susceptibility of HTLV-1-infected individuals to other infectious agents.

Introduction: Burkitt Lymphoma (BL) is an aggressive B-cell lymphoma with a translocation involving MYC and immunoglobulin(Ig) loci. It is most common in children, but also affects adults, and occurs in sporadic, endemic and HIV-associated forms. The Epstein-Barr virus (EBV)-associated endemic subtype is the most common pediatric cancer in equatorial Africa, but also occurs in other parts of the world, for example in the rain forest of Brazil. Intensive chemotherapy is effective, but the associated toxicity requires supportive care that is not readily available in resource-poor regions. Previously published molecular characterization of small numbers of tumors indicated that the mutation profiles of endemic and sporadic cases are similar, but not identical. One goal of the BLGSP is to conduct comprehensive molecular characterization of BL by sequencing DNA and RNA from a large BL cohort - including endemic, sporadic, pediatric and adult cases - in order to define the genetic and phenotypic features that drive these cancers. These data will be analyzed with an intent toward developing new therapeutic strategies that can be deployed worldwide. Methods: The goal is to collect 160 BL cases, of which 50% will be endemic, 38% sporadic (pediatric and adult) and 12% from HIV+ patients. For the discovery phase, each tumor requires case-matching normal DNA as well as treatment, outcome and other clinical information. The optimal source of tumor DNA and RNA is from frozen tissue with at least 50% tumor nuclei, but FFPE immobilization is also accepted. Accrual locations include Africa, Brazil, Europe and the US. The BLGSP has developed extensive standard operating procedures for tissue collection, pathology review and tissue processing to reduce the variation associated with these parameters in the interpretation of the results (see https://ocg.cancer.gov/programs/cgci/projects/burkitt-lymphoma). The project also established procedures that allow sharing of all clinical and sample information through the National Cancer Institute Genomic Data Commons (https://gdc.cancer.gov). Molecular characterization includes whole genome sequencing of tumor and normal DNA (80X and 40X coverage, respectively), RNA-sequencing (RNA-seq) and micro-RNA sequencing. These data will enable the BLGSP to identify chromosomal rearrangements, chromosomal copy number alternations, somatic mutations (single nucleotide, insertions, deletions), viral insertions, expression signatures, viral expressions and miRNA regulation of transcripts. Results: To date we have accrued 80 cases of BL of which 75% passed diagnostic pathology review. There was an additional 25% attrition at the tissue processing stage, either due to low quality nucleic acids or low percent tumor nuclei. We have completed sequencing for 45 cases, all but one of which have a MYC translocation involving one of the 3 Ig loci; one case has a MYC rearrangement by FISH analysis that is being characterized further. We have identified recurrent mutations in ID3, DDX3X, ARID1A, FOXO1, TP53, SMARCA4 and other genes. Most mutations are supported by the RNA-seq data, which is also useful in defining the pattern of EBV genome transcription. Preliminary unsupervised hierarchical clustering and principal component analysis of gene expression data defined sample clusters that do not correspond to mutation status or EBV infection, warranting further investigation. Some genes accumulated somatic mutations in a BL subtype-specific fashion. Discussion: BLGSP is an ongoing international collaborative project that will provide a comprehensive molecular portrait of BL subtypes when completed, with the potential to suggest new molecular targets for therapy that can eventually lead to effective treatments that are less toxic than the current regimens. Disclosures Casper: Janssen: Consultancy, Research Funding; Roche: Consultancy, Other: Travel, Accommodation, Expenses; TempTime: Consultancy, Other: Travel, Accommodation, Expenses; Up to Date: Patents & Royalties; GSK: Other: Travel, Accommodation, Expenses. Abramson:Kite Pharma: Consultancy; Abbvie: Consultancy; Seattle Genetics: Consultancy; Gilead: Consultancy. Noy:Pharmacyclics, LLC, an AbbVie Company: Other: travel, accommodations, expenses, Research Funding.

IL-17 is proinflammatory cytokine secreted by a unique CD4+ T (Th17) cell subset and proposed to play a role in host defense. We hypothesized that Th17 cells are lost in HIV-1 infection. HIV-1-infected children with plasma viremia below 50 copies/ml had IL-17 production, whereas those with detectable viremia had minimal secretion. These results imply viral-mediated destruction or impairment of Th17 cells and argue for complete suppression of viremia for reconstitution of Th17 cells.

HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develops HAM/TSP. CD4+ T cells are the main target of infection and play a pivotal role in regulating immunity to HTLV and are hypothesized to participate in the pathogenesis of HAM/TSP. The CD39 ectonucleotidase receptor is expressed on CD4+ T cells and based on co-expression with CD25, marks T cells with distinct regulatory (CD39+CD25+) and effector (CD39+CD25−) function. Here, we investigated the expression of CD39 on CD4+ T cells from a cohort of HAM/TSP patients, HTLV-1 asymptomatic carriers (AC), and matched uninfected controls. The frequency of CD39+ CD4+ T cells was increased in HTLV-1 infected patients, regardless of clinical status. More importantly, the proportion of the immunostimulatory CD39+CD25− CD4+ T-cell subset was significantly elevated in HAM/TSP patients as compared to AC and phenotypically had lower levels of the immunoinhibitory receptor, PD-1. We saw no difference in the frequency of CD39+CD25+ regulatory (Treg) cells between AC and HAM/TSP patients. However, these cells transition from being anergic to displaying a polyfunctional cytokine response following HTLV-1 infection. CD39−CD25+ T cell subsets predominantly secreted the inflammatory cytokine IL-17. We found that HAM/TSP patients had significantly fewer numbers of IL-17 secreting CD4+ T cells compared to uninfected controls. Taken together, we show that the expression of CD39 is upregulated on CD4+ T cells HAM/TSP patients. This upregulation may play a role in the development of the proinflammatory milieu through pathways both distinct and separate among the different CD39 T cell subsets. CD39 upregulation may therefore serve as a surrogate diagnostic marker of progression and could potentially be a target for interventions to reduce the development of HAM/TSP., Author Summary Human T-lymphotropic virus type 1 (HTLV-1) has been estimated to infect 10–20 million worldwide. The majority of infected individuals are asymptomatic, however, 2% to 3% develop a neurodegenerative disorder called HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The reasons why persons with HTLV-1 develop these complications appear to be multiple and complex. Cellular immune response has been implicated in the development of inflammatory alterations in these patients, however the pathogenic mechanisms for disease progression remain unclear. Regulatory CD4+ T cells (Treg) and Th17 cells derive from a common progenitor and conflicting results regarding frequency and function are found in the development of HAM/TSP. The expression of the CD39 ectoenzyme, a molecule that can mediate immunostimulatory and inhibitory effects, is useful to define IL-17 secreting cell populations, suppressive CD4+ T cells and CD4+ T cells with immunostimulatory properties. The interplay of these T-cell subsets may reveal important aspects of HAM/TSP pathogenesis. In this study, we performed an evaluation of the immunoregulatory CD4+ T-cell subsets defined by CD39 expression including Th17 cells. Our results present phenotypic and functional alterations in the CD4+ T cell profile that could account for the transition from asymptomatic status to HAM/TSP, predicting clinical disease risk and tracking disease progression.

Background The Interleukin 28B (IL28B) rs12979860 polymorphisms was recently reported to be associated with the human T-cell leukemia virus type 1 (HTLV-1) proviral load (PvL) and the development of the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Methods In an attempt to examine this hypothesis, we assessed the association of the rs12979860 genotypes with HTLV-1 PvL levels and clinical status in 112 unrelated Brazilian subjects (81 HTLV-1 asymptomatic carriers, 24 individuals with HAM/TSP and 7 with Adult T cell Leukemia/Lymphoma (ATLL)). Results All 112 samples were successfully genotyped and their PvLs compared. Neither the homozygote TT nor the heterozygote CT mutations nor the combination genotypes (TT/CT) were associated with a greater PvL. We also observed no significant difference in allele distribution between asymptomatic carriers and patients with HTLV-1 associated HAM/TSP. Conclusions Our study failed to support the previously reported positive association between the IL28B rs12979860 polymorphisms and an increased risk of developing HAM/TSP in the Brazilian population.

The complexity of immunoregulation has focused attention on the CD4+ T “suppressor” regulatory cell (Treg), which helps maintain balance between immunity and tolerance. An immunoregulatory T cell population that upon activation amplifies cellular immune responses was described in murine models more than thirty years ago. However, no study has yet identified a naturally occurring T “inducer” cell type. Here, we report that the ectoenzyme CD39/NTPDase1 (ecto-nucleoside triphosphate diphosphohydrolase 1) helps to delineate a novel population of human “inducer” CD4+ T cells (TInd) that significantly increases the proliferation and cytokine production of responder T cells in a dose-dependent manner. Furthermore, this unique TInd cell subset produces a distinct repertoire of cytokines in comparison to the other CD4+ T cell subsets. We propose that this novel CD4+ T cell population counterbalances the suppressive activity of suppressor Treg cells in peripheral blood and serves as a calibrator of immunoregulation.

Summary Human T lymphotropic virus type 1 (HTLV-1) infects 10–20 million people worldwide. The majority of infected individuals are asymptomatic; however, approximately 3% develop the debilitating neurological disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is also currently no cure, vaccine or effective therapy for HTLV-1 infection, and the mechanisms for progression to HAM/TSP remain unclear. NK T cells are an immunoregulatory T cell subset whose frequencies and effector functions are associated critically with immunity against infectious diseases. We hypothesized that NK T cells are associated with HAM/TSP progression. We measured NK T cell frequencies and absolute numbers in individuals with HAM/TSP infection from two cohorts on two continents: São Paulo, Brazil and San Francisco, CA, USA, and found significantly lower levels when compared with healthy subjects and/or asymptomatic carriers. Also, the circulating NK T cell compartment in HAM/TSP subjects is comprised of significantly more CD4+ and fewer CD8+ cells than healthy controls. These findings suggest that lower numbers of circulating NK T cells and enrichment of the CD4+ NK T subset are associated with HTLV-1 disease progression.

Pulmonary toxoplasmosis is rare in immunocompetent subjects. Here, we describe a 41-year-old previously healthy male patient who presented to the emergency department of a hospital with a life-threatening case of pneumonia due to Toxoplasma gondii infection, which responded to specific therapy. Clinical and image-based findings overlap with those for atypical pneumonias, and toxoplasmosis should be considered in the differential diagnosis-especially if immunoglobulin M-specific antibodies are detected. Universidade Federal de São Paulo, BR-04044010 São Paulo, Brazil Hosp Serv Publ Estadual São Paulo, São Paulo, Brazil Univ São Paulo, Inst Med Trop São Paulo, São Paulo, Brazil Universidade Federal de São Paulo, EPM, São Paulo, Brazil Web of Science

Background An estimated 10–20 million individuals are infected with the retrovirus human T-cell leukemia virus type 1 (HTLV-1). While the majority of these individuals remain asymptomatic, 0.3-4% develop a neurodegenerative inflammatory disease, termed HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HAM/TSP results in the progressive demyelination of the central nervous system and is a differential diagnosis of multiple sclerosis (MS). The etiology of HAM/TSP is unclear, but evidence points to a role for CNS-inflitrating T-cells in pathogenesis. Recently, the HTLV-1-Tax protein has been shown to induce transcription of the human endogenous retrovirus (HERV) families W, H and K. Intriguingly, numerous studies have implicated these same HERV families in MS, though this association remains controversial. Results Here, we explore the hypothesis that HTLV-1-infection results in the induction of HERV antigen expression and the elicitation of HERV-specific T-cells responses which, in turn, may be reactive against neurons and other tissues. PBMC from 15 HTLV-1-infected subjects, 5 of whom presented with HAM/TSP, were comprehensively screened for T-cell responses to overlapping peptides spanning HERV-K(HML-2) Gag and Env. In addition, we screened for responses to peptides derived from diverse HERV families, selected based on predicted binding to predicted optimal epitopes. We observed a lack of responses to each of these peptide sets. Conclusions Thus, although the limited scope of our screening prevents us from conclusively disproving our hypothesis, the current study does not provide data supporting a role for HERV-specific T-cell responses in HTLV-1 associated immunopathology.

The T cell immunoglobulin mucin 3 (Tim-3) receptor is highly expressed on HIV-1-specific T cells, rendering them partially “exhausted” and unable to contribute to the effective immune mediated control of viral replication. To elucidate novel mechanisms contributing to the HTLV-1 neurological complex and its classic neurological presentation called HAM/TSP (HTLV-1 associated myelopathy/tropical spastic paraparesis), we investigated the expression of the Tim-3 receptor on CD8+ T cells from a cohort of HTLV-1 seropositive asymptomatic and symptomatic patients. Patients diagnosed with HAM/TSP down-regulated Tim-3 expression on both CD8+ and CD4+ T cells compared to asymptomatic patients and HTLV-1 seronegative controls. HTLV-1 Tax-specific, HLA-A*02 restricted CD8+ T cells among HAM/TSP individuals expressed markedly lower levels of Tim-3. We observed Tax expressing cells in both Tim-3+ and Tim-3− fractions. Taken together, these data indicate that there is a systematic downregulation of Tim-3 levels on T cells in HTLV-1 infection, sustaining a profoundly highly active population of potentially pathogenic T cells that may allow for the development of HTLV-1 complications., Author Summary The retrovirus, Human T lymphotropic virus type 1 (HTLV-1) infects 10–20 million people worldwide. The majority of infected individuals are asymptomatic; however, approximately 3% develop the debilitating neurological disease, HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is also currently no cure, vaccine or effective therapy for HTLV-1 infection. The precise role of CD8+ killer T cells in the control or contribution of HTLV-1 disease progression remains unclear. The T-cell immunoglobulin mucin domain-containing (Tim) proteins are type 1 transmembrane proteins. Three human Tim proteins (Tim-1, -3, and -4) exist and display markedly diverse expression patterns and functions. Tim-3 is upregulated on CD8+ T cells during chronic viral infections leading to a population of poorly functioning T cells. We investigated the expression of Tim-3 on T cells from patients with asymptomatic and symptomatic HTLV-1 infection and compared this with HTLV-1 uninfected donors. Patients diagnosed with HAM/TSP down-regulated Tim-3 expression on T cells when compared to asymptomatic patients and uninfected controls. Our study provides evidence of a novel mechanism for the persistent inflammation observed in HTLV-1 infected patients with neurological deficits and significantly advances our understanding of how the Tim-3 pathway functions.