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1.
Am J Manag Care ; 30(6): 285-288, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38912954

ABSTRACT

OBJECTIVES: This study explores the concern that annual high-deductible commercial insurance plan design may yield higher out-of-pocket costs when an episode of maternity care spans 2 years, exposing patients to their cost-sharing limits twice during their episode of care. STUDY DESIGN: Cross-sectional study of Health Care Cost Institute commercial claims. METHODS: The study sample comprises 1,379,300 deliveries among high-deductible health plan enrollees in years 2012 through 2021. Patients' mean cost sharing is calculated across all service types for 3 time periods: (1) delivery hospitalization, (2) maternity episode from 40 weeks prior to delivery hospitalization through 12 weeks after discharge, and (3) extended period spanning 3 years from January of the year before delivery through December of the year after delivery. RESULTS: For each of the 3 episode measurements, mean out-of-pocket spending is highest among those who deliver in January and declines in each subsequent month until August and September (the delivery months with most pregnancy and postpartum periods within the same year), then flattens for the remainder of the year. Mean cost sharing for the maternity episode was $6308 in January and $4998 in December, a difference of $1310. Patients delivering in January also had mean out-of-pocket costs $1491 greater for delivery hospitalization and $1005 greater over the 3-year period than patients delivering in December. CONCLUSIONS: Higher out-of-pocket spending is observed when patients face their cost-sharing limits twice within an episode of maternity care, and this difference persists even when evaluating 3 calendar years of patients' out-of-pocket spending.


Subject(s)
Cost Sharing , Deductibles and Coinsurance , Health Expenditures , Humans , Female , Pregnancy , Cross-Sectional Studies , Deductibles and Coinsurance/economics , Deductibles and Coinsurance/statistics & numerical data , Health Expenditures/statistics & numerical data , Adult , Cost Sharing/economics , United States , Insurance, Health/economics , Insurance, Health/statistics & numerical data , Financing, Personal/statistics & numerical data
2.
Health Aff Sch ; 2(5): qxae062, 2024 May.
Article in English | MEDLINE | ID: mdl-38808329

ABSTRACT

Recent price transparency laws are designed to better inform patients as they compare hospital options and "shop" for health care services. In addition to prices, underinsured patients seeking care need information on financial assistance, discounts, payment plans, and upfront payment requirements to compare the affordability of care across hospitals. Little is known about the availability of this information and the experience of prospective patients seeking it. We contacted a random sample of 10% of general short-term hospitals across the United States in this "secret shopper" telephone study to assess financial options and navigation challenges faced by underinsured patients in need of a non-emergency procedure. The administrative friction was substantial. Most hospitals have 3 siloed offices for (1) financial assistance, (2) payment plans and discounts, and (3) upfront payment requirements. All relevant offices were unreachable in 3 attempted calls at 18.1% of hospitals. Among hospitals with available information, the majority have financial options for patients: 86.7% of hospitals offer financial assistance and 97.0% of hospitals offer payment plans to underinsured patients for non-emergency care. The length and terms of payments plans varied widely for hospital-administered and third-party financing arrangements. Upfront payments were sometimes required, potentially posing barriers for patients without cash or credit access.

3.
JAMA Health Forum ; 5(3): e240231, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38551590

ABSTRACT

This cross-sectional study examines the prevalence of hospital-promoted medical payment products (MPPs) by whether hospitals offered any MPP or an interest-bearing MPP.


Subject(s)
Hospitals , Medicare , United States , Prevalence
4.
J Sports Sci ; 41(16): 1564-1572, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37979195

ABSTRACT

This study examined the immediate effects of multidirectional elastic tape (MET) on passive ankle joint torque in healthy adults. A randomised crossover trial evaluated four tape conditions (no-tape-NT, low-tension-LT, medium-tension-MT, and high-tension-HT) at two angular speeds on peak dorsiflexion torque, low- (stiffness 1) and high-torque stiffness (stiffness 2), area under the loading curve (AUC) and hysteresis. Twenty-two adults completed the study (17 females; mean (SD): age 26.0 (6.9) years, height 1.7 (0.1) m, body mass 71.1 (20.2) kg. There was no significant condition-by-speed interaction for any ankle torque variable. There was a significant main effect of condition on peak dorsiflexion torque, stiffness 1, and AUC, but not stiffness 2 or hysteresis. Post-hoc tests revealed that peak dorsiflexion torque, stiffness 1 and AUC were significantly lower in the NT condition, compared to the three taped conditions, and between the LT and HT conditions, though the effect sizes were considered small. MET applied with increasing levels of pre-tension, led to a small and incremental increase in stretch resistance and elastic energy stored (range 5.5% to 12.5%) during passive ankle dorsiflexion. Importantly, effect sizes were small and may not translate to measurable improvements in muscle-tendon unit performance during dynamic exercise.


Subject(s)
Ankle Joint , Muscle, Skeletal , Adult , Female , Humans , Ankle , Exercise , Range of Motion, Articular , Tendons , Torque , Male
5.
J Bodyw Mov Ther ; 34: 87-95, 2023 04.
Article in English | MEDLINE | ID: mdl-37301563

ABSTRACT

OBJECTIVES: This study assessed the immediate effect of unilateral posterior-anterior lumbar mobilisations on trunk and lower limb flexibility in asymptomatic individuals. STUDY DESIGN: Randomised cross-over trial. PARTICIPANTS: Twenty-seven participants (age = 26.0 years ±6.4) with no current or recent history of lower back or leg pain/surgery completed the study. MAIN OUTCOME MEASURES: Participants attended two sessions, receiving either grade 3 ('treatment') or grade 1 ('sham') unilateral spinal mobilisations. Outcome measures (modified-modified Schober's test [MMST], ninety-ninety test [NNT], and passive straight-leg raise [PSLR]) were assessed immediately before and after (post-1 and post-2) the intervention. An instrumented hand-held dynamometer was used to measure the change in NNT and PSLR joint angle (deg) and passive stiffness (Nm/deg) pre- and post-intervention. RESULTS: The mean change in PSLR angle at the first (P1) and maximal (P2) point of discomfort following the treatment was 4.8° and 5.5°, and 5.6° and 5.7°, larger than the sham at post-1 and post-2, respectively. There was no effect of the treatment on the PSLR at P1 or P2 for the contralateral limb at either timepoint. There was no effect of the treatment on MMST distance, NNT angle or passive stiffness, or PSLR passive stiffness, for either limb. CONCLUSIONS: Immediate effects of unilateral posterior-anterior lumbar mobilisations in asymptomatic individuals are isolated to treatment side and limited to a small increase in PSLR range, with no change in lumbar motion or the NNT test.


Subject(s)
Leg , Lower Extremity , Humans , Adult , Cross-Over Studies , Lumbosacral Region , Pain , Range of Motion, Articular
6.
PLoS Pathog ; 19(4): e1011298, 2023 04.
Article in English | MEDLINE | ID: mdl-37075079

ABSTRACT

The global SARS-CoV-2 pandemic prompted rapid development of COVID-19 vaccines. Although several vaccines have received emergency approval through various public health agencies, the SARS-CoV-2 pandemic continues. Emergent variants of concern, waning immunity in the vaccinated, evidence that vaccines may not prevent transmission and inequity in vaccine distribution have driven continued development of vaccines against SARS-CoV-2 to address these public health needs. In this report, we evaluated a novel self-amplifying replicon RNA vaccine against SARS-CoV-2 in a pigtail macaque model of COVID-19 disease. We found that this vaccine elicited strong binding and neutralizing antibody responses against homologous virus. We also observed broad binding antibody against heterologous contemporary and ancestral strains, but neutralizing antibody responses were primarily targeted to the vaccine-homologous strain. While binding antibody responses were sustained, neutralizing antibody waned to undetectable levels in some animals after six months but were rapidly recalled and conferred protection from disease when the animals were challenged 7 months after vaccination as evident by reduced viral replication and pathology in the lower respiratory tract, reduced viral shedding in the nasal cavity and lower concentrations of pro-inflammatory cytokines in the lung. Cumulatively, our data demonstrate in pigtail macaques that a self-amplifying replicon RNA vaccine can elicit durable and protective immunity to SARS-CoV-2 infection. Furthermore, these data provide evidence that this vaccine can provide durable protective efficacy and reduce viral shedding even after neutralizing antibody responses have waned to undetectable levels.


Subject(s)
COVID-19 Vaccines , mRNA Vaccines , COVID-19 Vaccines/immunology , Macaca nemestrina , Lung/immunology , Lung/virology , SARS-CoV-2/physiology , Animals , Antibodies, Neutralizing/immunology , COVID-19/transmission
7.
Mol Ther ; 31(4): 1046-1058, 2023 04 05.
Article in English | MEDLINE | ID: mdl-36965482

ABSTRACT

Mother-to-child transmission is a major route for infections in newborns. Vaccination in mothers to leverage the maternal immune system is a promising approach to vertically transfer protective immunity. During infectious disease outbreaks, such as the 2016 Zika virus (ZIKV) outbreak, rapid availability of vaccines can prove critical in reducing widespread disease burden. The recent successes of mRNA vaccines support their evaluation in pregnant animal models to justify their use in neonatal settings. Here we evaluated immunogenicity of self-amplifying replicon (repRNA) vaccines, delivered with our clinical-stage LION nanoparticle formulation, in pregnant rabbits using ZIKV and HIV-1 as model disease targets. We showed that LION/repRNA vaccines induced robust antigen-specific antibody responses in adult pregnant rabbits that passively transferred to newborn kits in utero. Using a matrixed study design, we further elucidate the effect of vaccination in kits on the presence of pre-existing maternal antibodies. Our findings showed that timing of maternal vaccination is critical in maximizing in utero antibody transfer, and subsequent vaccination in newborns maintained elevated antibody levels compared with no vaccination. Overall, our results support further development of the LION/repRNA vaccine platform for maternal and neonatal settings.


Subject(s)
Vaccines , Zika Virus Infection , Zika Virus , Pregnancy , Animals , Female , Rabbits , Infectious Disease Transmission, Vertical/prevention & control , Antibodies, Viral , Antibodies, Neutralizing
8.
Health Aff (Millwood) ; 42(2): 246-251, 2023 02.
Article in English | MEDLINE | ID: mdl-36745825

ABSTRACT

Medicare Advantage (MA) enrollment increased by 22.2 million beneficiaries (337.0 percent) from 2006 through 2022, whereas traditional Medicare enrollment declined by 1.0 million (-2.9 percent) over that period. In 2022, adjusted MA penetration was 49.9 percent nationally, and 24.0 percent of Medicare beneficiaries with Parts A and B lived in a county with adjusted MA penetration equal to or exceeding 60 percent.


Subject(s)
Medicare Part C , Aged , Humans , United States
9.
Am J Manag Care ; 28(9): e347-e350, 2022 09 01.
Article in English | MEDLINE | ID: mdl-36121367

ABSTRACT

OBJECTIVES: This study investigates a sample of the pricing data released by hospitals under the price transparency law effective January 2021 to better understand the prices paid by health insurance exchange (HIX) plans relative to commercial group and Medicare Advantage plans. STUDY DESIGN: Cross-sectional analysis of hospital pricing data. METHODS: We compared allowed amounts for 25 common inpatient services and 56 common outpatient services across 22 hospital-insurer dyads, selected by the availability of plan-specific pricing data from the top 100 hospitals by bed counts and the top 100 hospitals by gross revenue based on 2017 CMS data. RESULTS: Insurers in our sample generally negotiated allowed amounts for their HIX plans that were lower than their commercial group rates and well above their Medicare Advantage contracts within the same hospital. CONCLUSIONS: Allowed amounts for HIX plans were generally lower than commercial group rates and higher than Medicare Advantage rates. Better information on HIX pricing is needed as the federal government and states consider additional ways to expand health care coverage, such as public options or expanded Medicaid or Medicare eligibility.


Subject(s)
Insurance Carriers , Medicare Part C , Aged , Costs and Cost Analysis , Cross-Sectional Studies , Hospitals , Humans , United States
10.
bioRxiv ; 2022 Aug 09.
Article in English | MEDLINE | ID: mdl-35982677

ABSTRACT

The global SARS-CoV-2 pandemic prompted rapid development of COVID-19 vaccines. Although several vaccines have received emergency approval through various public health agencies, the SARS-CoV-2 pandemic continues. Emergent variants of concern, waning immunity in the vaccinated, evidence that vaccines may not prevent transmission and inequity in vaccine distribution have driven continued development of vaccines against SARS-CoV-2 to address these public health needs. In this report, we evaluated a novel self-amplifying replicon RNA vaccine against SARS-CoV-2 in a pigtail macaque model of COVID-19 disease. We found that this vaccine elicited strong binding and neutralizing antibody responses. While binding antibody responses were sustained, neutralizing antibody waned to undetectable levels after six months but were rapidly recalled and conferred protection from disease when the animals were challenged 7 months after vaccination as evident by reduced viral replication and pathology in the lower respiratory tract, reduced viral shedding in the nasal cavity and lower concentrations of pro-inflammatory cytokines in the lung. Cumulatively, our data demonstrate in pigtail macaques that a self-amplifying replicon RNA vaccine can elicit durable and protective immunity to SARS-CoV-2 infection. Furthermore, these data provide evidence that this vaccine can provide durable protective efficacy and reduce viral shedding even after neutralizing antibody responses have waned to undetectable levels.

11.
EBioMedicine ; 83: 104196, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35932641

ABSTRACT

BACKGROUND: In late 2021, the SARS-CoV-2 Omicron (B.1.1.529) variant of concern (VoC) was reported with many mutations in the viral spike protein that were predicted to enhance transmissibility and allow viral escape of neutralizing antibodies. Within weeks of the first report of B.1.1.529, this VoC has rapidly spread throughout the world, replacing previously circulating strains of SARS-CoV-2 and leading to a resurgence in COVID-19 cases even in populations with high levels of vaccine- and infection-induced immunity. Studies have shown that B.1.1.529 is less sensitive to protective antibody conferred by previous infections and vaccines developed against earlier lineages of SARS-CoV-2. The ability of B.1.1.529 to spread even among vaccinated populations has led to a global public health demand for updated vaccines that can confer protection against B.1.1.529. METHODS: We rapidly developed a replicating RNA vaccine expressing the B.1.1.529 spike and evaluated immunogenicity in mice and hamsters. We also challenged hamsters with B.1.1.529 and evaluated whether vaccination could protect against viral shedding and replication within respiratory tissue. FINDINGS: We found that mice previously immunized with A.1-specific vaccines failed to elevate neutralizing antibody titers against B.1.1.529 following B.1.1.529-targeted boosting, suggesting pre-existing immunity may impact the efficacy of B.1.1.529-targeted boosters. Furthermore, we found that our B.1.1.529-targeted vaccine provides superior protection compared to the ancestral A.1-targeted vaccine in hamsters challenged with the B.1.1.529 VoC after a single dose of each vaccine. INTERPRETATION: Our data suggest that B.1.1.529-targeted vaccines may provide superior protection against B.1.1.529 but pre-existing immunity and timing of boosting may need to be considered for optimum protection. FUNDING: This research was supported in part by the Intramural Research Program, NIAID/NIH, Washington Research Foundation and by grants 27220140006C (JHE), AI100625, AI151698, and AI145296 (MG).


Subject(s)
COVID-19 , Viral Vaccines , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , Cricetinae , Mice , RNA , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Vaccines, Synthetic , mRNA Vaccines
12.
EBioMedicine ; 82: 104188, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35907368

ABSTRACT

BACKGROUND: Crimean-Congo hemorrhagic fever virus is the cause of a severe hemorrhagic fever with cases reported throughout a wide-geographic region. Spread by the bite of infected ticks, contact with infected livestock or in the health care setting, disease begins as a non-specific febrile illness that can rapidly progress to hemorrhagic manifestations. Currently, there are no approved vaccines and antivirals such as ribavirin have unclear efficacy. Thus treatment is mostly limited to supportive care. METHODS: In this report we evaluated an alphavirus-based replicon RNA vaccine expressing either the CCHFV nucleoprotein or glycoprotein precursor in a stringent, heterologous lethal challenge mouse model. FINDINGS: Vaccination with the RNA expressing the nucleoprotein alone could confer complete protection against clinical disease, but vaccination with a combination of both the nucleoprotein and glycoprotein precursor afforded robust protection against disease and viral replication. Protection from lethal challenge required as little as a single immunization with 100ng of RNA. Unexpectedly, analysis of the immune responses elicited by the vaccine components showed that vaccination resulted in antibodies against the internal viral nucleoprotein and cellular immunity against the virion-exposed glycoproteins. INTERPRETATION: Cumulatively this vaccine conferred robust protection against Crimean-Congo hemorrhagic fever virus and supports continued development of this vaccine candidate. FUNDING: This research was supported by the Intramural Research Program of the NIAID/NIH and HDT Bio.


Subject(s)
Hemorrhagic Fever Virus, Crimean-Congo , Hemorrhagic Fever, Crimean , Animals , Antibodies, Viral , Glycoproteins , Hemorrhagic Fever Virus, Crimean-Congo/genetics , Hemorrhagic Fever, Crimean/prevention & control , Immunity , Mice , Mice, Knockout , Nucleoproteins , RNA , Vaccination , Vaccines, Synthetic , mRNA Vaccines
13.
Elife ; 112022 02 22.
Article in English | MEDLINE | ID: mdl-35191378

ABSTRACT

Despite mass public health efforts, the SARS-CoV2 pandemic continues as of late 2021 with resurgent case numbers in many parts of the world. The emergence of SARS-CoV2 variants of concern (VoCs) and evidence that existing vaccines that were designed to protect from the original strains of SARS-CoV-2 may have reduced potency for protection from infection against these VoC is driving continued development of second-generation vaccines that can protect against multiple VoC. In this report, we evaluated an alphavirus-based replicating RNA vaccine expressing Spike proteins from the original SARS-CoV-2 Alpha strain and recent VoCs delivered in vivo via a lipid inorganic nanoparticle. Vaccination of both mice and Syrian Golden hamsters showed that vaccination induced potent neutralizing titers against each homologous VoC but reduced neutralization against heterologous challenges. Vaccinated hamsters challenged with homologous SARS-CoV2 variants exhibited complete protection from infection. In addition, vaccinated hamsters challenged with heterologous SARS-CoV-2 variants exhibited significantly reduced shedding of infectious virus. Our data demonstrate that this vaccine platform can be updated to target emergent VoCs, elicits significant protective immunity against SARS-CoV2 variants and supports continued development of this platform.


Since 2019, the SARS-CoV-2 virus has spread worldwide and caused hundreds of millions of cases of COVID-19. Vaccines were rapidly developed to protect people from becoming severely ill from the virus and decrease the risk of death. However, new variants ­ such as Alpha, Beta and Omicron ­ have emerged that the vaccines do not work as well against, contributing to the ongoing spread of the virus. One way to overcome this is to create a vaccine that can be quickly and easily updated to target new variants, like the vaccine against influenza. Many of the vaccines made against COVID-19 use a new technology to introduce the RNA sequence of the spike protein on the surface of SARS-CoV-2 into our cells. Once injected, our cells use their own machinery to build the protein, or 'antigen', so the immune system can learn how to recognize and destroy the virus. Here, Hawman et al. have renovated an RNA vaccine they made in 2020 which provides immunity against the original strain of SARS-CoV-2 in monkeys and mice. In the newer versions of the vaccine, the RNA was updated with a sequence that matches the spike protein on the Beta or Alpha variant of the virus. Both the original and updated vaccines were then administered to mice and hamsters to see how well they worked against SARS-CoV-2 infections. The experiment showed that all three vaccines caused the animals to produce antibodies that can neutralize the original, Alpha and Beta strains of the virus. Vaccinated hamsters were then infected with one of the three variants ­ either matched or mismatched to their vaccination ­ to see how much protection each vaccine provided. All the vaccines reduced the amount of virus in the animals after infection and mitigated damage in their lungs. But animals that received a vaccine which corresponded to the SARS-CoV-2 strain they were infected with had slightly better protection. These findings suggest that these vaccines work best when their RNA sequence matches the strain responsible for the infection; however, even non-matched vaccines still provide a decent degree of protection. Furthermore, the data demonstrate that the vaccine platform created by Hawman et al. can be easily updated to target new strains of SARS-CoV-2 that may emerge in the future. Recently, the Beta variant of the vaccine entered clinical trials in the United States (led by HDT Bio) to evaluate whether it can be used as a booster in previously vaccinated individuals as well as unvaccinated participants.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Antibodies, Neutralizing , COVID-19/prevention & control , COVID-19 Vaccines , Cricetinae , Humans , Mice , RNA, Viral , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/metabolism , Vaccines, Synthetic , mRNA Vaccines
14.
bioRxiv ; 2021 Dec 13.
Article in English | MEDLINE | ID: mdl-34931189

ABSTRACT

Despite mass public health efforts, the SARS-CoV2 pandemic continues as of late-2021 with resurgent case numbers in many parts of the world. The emergence of SARS-CoV2 variants of concern (VoC) and evidence that existing vaccines that were designed to protect from the original strains of SARS-CoV-2 may have reduced potency for protection from infection against these VoC is driving continued development of second generation vaccines that can protect against multiple VoC. In this report, we evaluated an alphavirus-based replicating RNA vaccine expressing Spike proteins from the original SARS-CoV-2 Alpha strain and recent VoCs delivered in vivo via a lipid inorganic nanoparticle. Vaccination of both mice and Syrian Golden hamsters showed that vaccination induced potent neutralizing titers against each homologous VoC but reduced neutralization against heterologous challenges. Vaccinated hamsters challenged with homologous SARS-CoV2 variants exhibited complete protection from infection. In addition, vaccinated hamsters challenged with heterologous SARS-CoV-2 variants exhibited significantly reduced shedding of infectious virus. Our data demonstrate that this vaccine platform elicits significant protective immunity against SARS-CoV2 variants and supports continued development of this platform.

15.
Front Immunol ; 12: 800723, 2021.
Article in English | MEDLINE | ID: mdl-34992610

ABSTRACT

The ongoing COVID-19 vaccine rollout is critical for reducing SARS-CoV-2 infections, hospitalizations, and deaths worldwide. Unfortunately, massive disparities exist in getting vaccines to vulnerable populations, including people living with HIV. Preliminary studies indicate that COVID-19 mRNA vaccines are safe and immunogenic in people living with HIV that are virally suppressed with potent antiretroviral therapy but may be less efficacious in immunocompromised individuals. This raises the concern that COVID-19 vaccines may be less effective in resource poor settings with limited access to antiretroviral therapy. Here, we evaluated the immunogenicity of a single dose COVID-19 replicon RNA vaccine expressing Spike protein (A.1) from SARS-CoV-2 (repRNA-CoV2S) in immunocompromised, SIV infected and immune competent, naïve pigtail macaques. Moderate vaccine-specific cellular Th1 T-cell responses and binding and neutralizing antibodies were induced by repRNA-CoV2S in SIV infected animals and naïve animals. Furthermore, vaccine immunogenicity was elicited even among the animals with the highest SIV viral burden or lowest peripheral CD4 counts prior to immunization. This study provides evidence that a SARS-CoV-2 repRNA vaccine could be employed to induce strong immunity against COVID-19 in HIV infected and other immunocompromised individuals.


Subject(s)
COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , Immunity, Cellular/drug effects , Immunity, Humoral/drug effects , Immunogenicity, Vaccine , Simian Acquired Immunodeficiency Syndrome/immunology , Simian Immunodeficiency Virus/immunology , Spike Glycoprotein, Coronavirus/administration & dosage , Vaccine Efficacy , mRNA Vaccines/administration & dosage , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines/genetics , COVID-19 Vaccines/immunology , Cells, Cultured , Disease Models, Animal , Host-Pathogen Interactions , Immunocompromised Host , Macaca nemestrina , Male , Simian Acquired Immunodeficiency Syndrome/blood , Simian Acquired Immunodeficiency Syndrome/virology , Simian Immunodeficiency Virus/pathogenicity , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Th1 Cells/drug effects , Th1 Cells/immunology , Th1 Cells/virology , Time Factors , Vaccination , mRNA Vaccines/genetics , mRNA Vaccines/immunology
16.
BMC Res Notes ; 13(1): 462, 2020 Sep 29.
Article in English | MEDLINE | ID: mdl-32993774

ABSTRACT

OBJECTIVE: Restriction-Modification (R-M) systems are ubiquitous in bacteria and were considered for years as rudimentary immune systems that protect bacterial cells from foreign DNA. Currently, these R-M systems are recognized as important players in global gene expression and other cellular processes such us virulence and evolution of genomes. Here, we report the role of the unique DNA methyltransferase in Mycobacterium smegmatis, which shows a moderate degree of sequence similarity to MamA, a previously characterized methyltransferase that affects gene expression in Mycobacterium tuberculosis and is important for survival under hypoxic conditions. RESULTS: We found that depletion of mamA levels impairs growth and produces elongated cell bodies. Microscopy revealed irregular septation and unevenly distributed DNA, with large areas devoid of DNA and small DNA-free cells. Deletion of MSMEG_3214, a predicted endonuclease-encoding gene co-transcribed with mamA, restored the WT growth phenotype in a mamA-depleted background. Our results suggest that the mamA-depletion phenotype can be explained by DNA cleavage by the apparent cognate restriction endonuclease MSMEG_3214. In addition, in silico analysis predicts that both MamA methyltransferase and MSMEG_3214 endonuclease recognize the same palindromic DNA sequence. We propose that MamA and MSMEG_3214 constitute a previously undescribed R-M system in M. smegmatis.


Subject(s)
Bacterial Proteins , DNA Restriction Enzymes , Mycobacterium smegmatis , Bacterial Proteins/genetics , Mycobacterium smegmatis/enzymology , Mycobacterium smegmatis/genetics , Mycobacterium tuberculosis , Virulence
17.
Sci Transl Med ; 12(555)2020 08 05.
Article in English | MEDLINE | ID: mdl-32690628

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic, caused by infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is having a deleterious impact on health services and the global economy, highlighting the urgent need for an effective vaccine. Such a vaccine would need to rapidly confer protection after one or two doses and would need to be manufactured using components suitable for scale up. Here, we developed an Alphavirus-derived replicon RNA vaccine candidate, repRNA-CoV2S, encoding the SARS-CoV-2 spike (S) protein. The RNA replicons were formulated with lipid inorganic nanoparticles (LIONs) that were designed to enhance vaccine stability, delivery, and immunogenicity. We show that a single intramuscular injection of the LION/repRNA-CoV2S vaccine in mice elicited robust production of anti-SARS-CoV-2 S protein IgG antibody isotypes indicative of a type 1 T helper cell response. A prime/boost regimen induced potent T cell responses in mice including antigen-specific responses in the lung and spleen. Prime-only immunization of aged (17 months old) mice induced smaller immune responses compared to young mice, but this difference was abrogated by booster immunization. In nonhuman primates, prime-only immunization in one intramuscular injection site or prime/boost immunizations in five intramuscular injection sites elicited modest T cell responses and robust antibody responses. The antibody responses persisted for at least 70 days and neutralized SARS-CoV-2 at titers comparable to those in human serum samples collected from individuals convalescing from COVID-19. These data support further development of LION/repRNA-CoV2S as a vaccine candidate for prophylactic protection against SARS-CoV-2 infection.


Subject(s)
Alphavirus/genetics , Antibodies, Neutralizing/immunology , Betacoronavirus/immunology , Coronavirus Infections/immunology , Pneumonia, Viral/immunology , RNA, Viral/genetics , Replicon/genetics , T-Lymphocytes/immunology , Viral Vaccines/immunology , Animals , Antibody Formation/immunology , COVID-19 , COVID-19 Vaccines , Coronavirus Infections/prevention & control , Inorganic Chemicals/chemistry , Lipids/chemistry , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Nanoparticles/chemistry , Pandemics , Primates , SARS-CoV-2
18.
bioRxiv ; 2020 May 28.
Article in English | MEDLINE | ID: mdl-32511417

ABSTRACT

The ongoing COVID-19 pandemic, caused by infection with SARS-CoV-2, is having a dramatic and deleterious impact on health services and the global economy. Grim public health statistics highlight the need for vaccines that can rapidly confer protection after a single dose and be manufactured using components suitable for scale-up and efficient distribution. In response, we have rapidly developed repRNA-CoV2S, a stable and highly immunogenic vaccine candidate comprised of an RNA replicon formulated with a novel Lipid InOrganic Nanoparticle (LION) designed to enhance vaccine stability, delivery and immunogenicity. We show that intramuscular injection of LION/repRNA-CoV2S elicits robust anti-SARS-CoV-2 spike protein IgG antibody isotypes indicative of a Type 1 T helper response as well as potent T cell responses in mice. Importantly, a single-dose administration in nonhuman primates elicited antibody responses that potently neutralized SARS-CoV-2. These data support further development of LION/repRNA-CoV2S as a vaccine candidate for prophylactic protection from SARS-CoV-2 infection.

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