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1.
Adv Sci (Weinh) ; 9(2): e2103240, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34761549

RESUMO

The outbreak of 2019 coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in a global pandemic. Despite intensive research, the current treatment options show limited curative efficacies. Here the authors report a strategy incorporating neutralizing antibodies conjugated to the surface of a photothermal nanoparticle (NP) to capture and inactivate SARS-CoV-2. The NP is comprised of a semiconducting polymer core and a biocompatible polyethylene glycol surface decorated with high-affinity neutralizing antibodies. The multifunctional NP efficiently captures SARS-CoV-2 pseudovirions and completely blocks viral infection to host cells in vitro through the surface neutralizing antibodies. In addition to virus capture and blocking function, the NP also possesses photothermal function to generate heat following irradiation for inactivation of virus. Importantly, the NPs described herein significantly outperform neutralizing antibodies at treating authentic SARS-CoV-2 infection in vivo. This multifunctional NP provides a flexible platform that can be readily adapted to other SARS-CoV-2 antibodies and extended to novel therapeutic proteins, thus it is expected to provide a broad range of protection against original SARS-CoV-2 and its variants.


Assuntos
Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , COVID-19/terapia , Imunoconjugados/administração & dosagem , Nanopartículas , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/fisiologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/imunologia , Reações Antígeno-Anticorpo , COVID-19/imunologia , COVID-19/virologia , Avaliação Pré-Clínica de Medicamentos , Temperatura Alta , Humanos , Imunoconjugados/imunologia , Imunoconjugados/uso terapêutico , Luz , Camundongos , Nanopartículas/uso terapêutico , Fosfatidiletanolaminas , Polietilenoglicóis , Polímeros , Receptores Virais/fisiologia , Semicondutores , Glicoproteína da Espícula de Coronavírus/imunologia , Tiadiazóis , Inativação de Vírus
3.
Virol Sin ; 35(6): 685-698, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32997322

RESUMO

The World Health Organization (WHO) has declared coronavirus disease 2019 (COVID-19) is the first pandemic caused by coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, there is no effective anti-SARS-CoV-2 drug approved worldwide for treatment of patients with COVID-19. Therapeutic options in response to the COVID-19 outbreak are urgently needed. To facilitate the better and faster development of therapeutic COVID-19 drugs, we present an overview of the global promising therapeutic drugs, including repurposing existing antiviral agents, network-based pharmacology research, antibody development and traditional Chinese medicine. Among all these drugs, we focus on the most promising drugs (such as favipiravir, tocilizumab, SARS-CoV-2 convalescent plasma, hydroxychloroquine, Lianhua Qingwen, interferon beta-1a, remdesivir, etc.) that have or will enter the final stage of human testing-phase III-IV clinical trials.


Assuntos
Anticorpos Antivirais/imunologia , Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , COVID-19/imunologia , Medicina Tradicional Chinesa/métodos , SARS-CoV-2/efeitos dos fármacos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/uso terapêutico , Alanina/análogos & derivados , Alanina/uso terapêutico , Amidas/uso terapêutico , Animais , Anticorpos Antivirais/administração & dosagem , Antivirais/farmacologia , COVID-19/terapia , Reposicionamento de Medicamentos , Humanos , Imunização Passiva , Pandemias , Pirazinas/uso terapêutico , Organização Mundial da Saúde , Soroterapia para COVID-19
4.
Viruses ; 12(9)2020 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-32842671

RESUMO

Filoviruses, including Ebola virus (EBOV) and Marburg virus (MARV), cause severe hemorrhagic fever in humans and nonhuman primates with high mortality rates. There is no approved therapy against these deadly viruses. Antiviral drug development has been hampered by the requirement of a biosafety level (BSL)-4 facility to handle infectious EBOV and MARV because of their high pathogenicity to humans. In this study, we aimed to establish a surrogate animal model that can be used for anti-EBOV and -MARV drug screening under BSL-2 conditions by focusing on the replication-competent recombinant vesicular stomatitis virus (rVSV) pseudotyped with the envelope glycoprotein (GP) of EBOV (rVSV/EBOV) and MARV (rVSV/MARV), which has been investigated as vaccine candidates and thus widely used in BSL-2 laboratories. We first inoculated mice, rats, and hamsters intraperitoneally with rVSV/EBOV and found that only hamsters showed disease signs and succumbed within 4 days post-infection. Infection with rVSV/MARV also caused lethal infection in hamsters. Both rVSV/EBOV and rVSV/MARV were detected at high titers in multiple organs including the liver, spleen, kidney, and lungs of infected hamsters, indicating acute and systemic infection resulting in fatal outcomes. Therapeutic effects of passive immunization with an anti-EBOV neutralizing antibody were specifically observed in rVSV/EBOV-infected hamsters. Thus, this animal model is expected to be a useful tool to facilitate in vivo screening of anti-filovirus drugs targeting the GP molecule.


Assuntos
Modelos Animais de Doenças , Ebolavirus/genética , Marburgvirus/genética , Estomatite Vesicular/virologia , Vesiculovirus/genética , Proteínas do Envelope Viral/genética , Animais , Anticorpos Antivirais/administração & dosagem , Cricetinae , Suscetibilidade a Doenças , Avaliação Pré-Clínica de Medicamentos , Ebolavirus/imunologia , Mesocricetus , Camundongos , Ratos , Vacinas Sintéticas , Estomatite Vesicular/patologia , Estomatite Vesicular/prevenção & controle , Estomatite Vesicular/terapia , Vesiculovirus/patogenicidade , Proteínas do Envelope Viral/imunologia , Carga Viral
5.
PLoS Negl Trop Dis ; 11(6): e0005637, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28628616

RESUMO

Chikungunya virus (CHIKV) is a mosquito-borne virus that causes a febrile syndrome in humans associated with acute and chronic debilitating joint and muscle pain. Currently no licensed vaccines or therapeutics are available to prevent or treat CHIKV infections. We recently isolated a panel of potently neutralizing human monoclonal antibodies (mAbs), one (4N12) of which exhibited prophylactic and post-exposure therapeutic activity against CHIKV in immunocompromised mice. Here, we describe the development of an engineered CHIKV mAb, designated SVIR001, that has similar antigen binding and neutralization profiles to its parent, 4N12. Because therapeutic administration of SVIR001 in immunocompetent mice significantly reduced viral load in joint tissues, we evaluated its efficacy in a rhesus macaque model of CHIKV infection. Rhesus macaques that were treated after infection with SVIR001 showed rapid elimination of viremia and less severe joint infiltration and disease compared to animals treated with SVIR002, an isotype control mAb. SVIR001 reduced viral burden at the site of infection and at distant sites and also diminished the numbers of activated innate immune cells and levels of pro-inflammatory cytokines and chemokines. SVIR001 therapy; however, did not substantively reduce the induction of CHIKV-specific B or T cell responses. Collectively, these results show promising therapeutic activity of a human anti-CHIKV mAb in rhesus macaques and provide proof-of-principle for its possible use in humans to treat active CHIKV infections.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Febre de Chikungunya/terapia , Fatores Imunológicos/administração & dosagem , Animais , Linfócitos B/imunologia , Febre de Chikungunya/patologia , Vírus Chikungunya/imunologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Macaca mulatta , Linfócitos T/imunologia , Resultado do Tratamento
6.
Antiviral Res ; 144: 44-47, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28529000

RESUMO

Despite useful in vivo activity, no therapeutic against dengue virus (DENV) has demonstrated efficacy in clinical trials. Herein, we explored dosing and virological endpoints to guide the design of human trials of VIS513, a pan-serotype anti-DENV IgG1 antibody, in non-human primates (NHPs). Dosing VIS513 pre- or post-peak viremia in NHPs neutralized infectious DENV although RNAemia remained detectable post-treatment; differential interaction of human IgGs with macaque Fc-gamma receptors may delay clearance of neutralized DENV. Our findings suggest useful antiviral utility of VIS513 and highlight an important consideration when evaluating virological endpoints of trials for anti-DENV biologics.


Assuntos
Anticorpos Antivirais/administração & dosagem , Antivirais/administração & dosagem , Vírus da Dengue/imunologia , Dengue/terapia , Fatores Imunológicos/administração & dosagem , Imunoterapia/métodos , Animais , Avaliação Pré-Clínica de Medicamentos , Macaca , Resultado do Tratamento
7.
Vopr Virusol ; 62(1): 36-41, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29323845

RESUMO

In spite of the vast arsenal of therapeutic agents, therapy of herpes virus infection (HVI) is very difficult, particularly in pregnant women, newborns and children in the first years of life, as well as in patients with immune deficiency. In this regard, possibility of using immunoglobulins for the treatment of HVI is currently attracting the attention of doctors. The aim of this work was to develop a suppository form of the drug containing donor immunoglobulins with high levels of neutralizing antibodies to herpes simplex virus types 1 and 2 for the treatment of chronic forms of herpetic disease. The study included the following steps: 1) selection of gamma-globulins with high antibody titer for HSV-1 and HSV-2 ELISA test; 2) determination of the level of neutralizing antibodies in the selected series of gamma-globulins in tests in tissue cultures and animals; 3) lyophilization of immunoglobulins; 4) development of the suppository form of the preparation containing gamma-globulin donors with high levels of neutralizing antibodies to HSV-1 and HSV-2; 5) study of the safety of the activity of neutralizing antibodies to HSV-1 and HSV-2 in the suppository form of the drug with hyaluronic acid used as immunomodulator. As the result of this work, immunoglobulin preparation in the suppository form was developed. The developed preparation meets the requirements for safety and efficacy. It is not toxic or pyrogenic. The problems of clinical use of this drug as a method of HVI therapy are discussed.


Assuntos
Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 2/imunologia , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/isolamento & purificação , Doença Crônica , Avaliação Pré-Clínica de Medicamentos , Cobaias , Herpes Simples/imunologia , Herpes Simples/virologia , Humanos , Soros Imunes/química , Masculino , Camundongos , Coelhos , Ratos , Supositórios/administração & dosagem , Supositórios/química
8.
Antiviral Res ; 111: 60-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25218949

RESUMO

Influenza virus is a global health concern due to its unpredictable pandemic potential. Frequent mutations of surface molecules, hemagglutinin (HA) and neuraminidase (NA), contribute to low efficacy of the annual flu vaccine and therapeutic resistance to standard antiviral agents. The populations at high risk of influenza virus infection, such as the elderly and infants, generally mount low immune responses to vaccines, and develop severe disease after infection. Novel therapeutics with high effectiveness and mutation resistance are needed. Previously, we described the generation of a fully human influenza virus matrix protein 2 (M2) specific monoclonal antibody (mAb), Z3G1, which recognized the majority of M2 variants from natural viral isolates, including highly pathogenic avian strains. Passive immunotherapy with Z3G1 significantly protected mice from the infection when administered either prophylactically or 1-2days post infection. In the present study, we showed that Z3G1 significantly protected mice from lethal infection when treatment was initiated 3days post infection. In addition, therapeutic administration of Z3G1 reduced lung viral titers in mice infected with different viral strains, including amantadine and oseltamivir-resistant strains. Furthermore, prophylactic and therapeutic administration of Z3G1 sustained O2 saturation and reduced lung pathology in monkeys infected with a pandemic H1N1 strain. Finally, de-fucosylated Z3G1 with an IgG1/IgG3 chimeric Fc region was generated (AccretaMab® Z3G1), and showed increased ADCC and CDC in vitro. Our data suggest that the anti-M2 mAb Z3G1 has great potential as a novel anti-flu therapeutic agent.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Imunização Passiva , Vírus da Influenza A/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/fisiologia , Vírus da Influenza A/fisiologia , Influenza Humana/imunologia , Influenza Humana/virologia , Macaca , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas da Matriz Viral/imunologia
9.
Vaccine ; 28(7): 1740-5, 2010 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-20034605

RESUMO

Governments and public health officials are preparing vaccination campaigns against the 2009 influenza A H1N1v pandemic strain. We evaluated two inactivated split-virion A/California/7/2009 H1N1v pandemic vaccines formulated with/without AS03(A), an oil-in-water emulsion adjuvant system containing tocopherol. This ongoing observer-blind study randomised 130 healthy adults aged 18-60 years to receive either AS03(A)-adjuvanted H1N1 vaccine containing 5.25 microg haemagglutinin (HA) (N=64) or non-adjuvanted H1N1 vaccine containing 21 microg HA (N=66) on Days 0 and 21. We performed a first analysis of reactogenicity and serum haemagglutination-inhibition (HI) antibody responses, 21 days after dose 1. Before vaccination, 12.5% in the AS03(A)-adjuvanted group and 13.1% in the non-adjuvanted group had vaccine-homologous HI titres >or=1:40. Immune responses were robust; HI seroconversion rates were 98.2% and 95.1% and HI seroprotection rates were 98.2% and 98.4%, respectively in the AS03(A) and non-adjuvanted groups. The vaccines were well tolerated with similar adverse event profiles. Solicited injection site and general symptoms were reported more frequently for AS03(A)-adjuvanted vaccine but these were transient and mainly mild to moderate in intensity. Based on accepted immunological surrogates, these preliminary data suggest that one dose of either AS03(A)-adjuvanted H1N1v vaccine at a reduced HA dose or non-adjuvanted H1N1v vaccine at a fourfold higher dose is sufficient to immunise healthy adults. The strong immune response is consistent with prevalent immunological priming but as this and the ability to mount immune response after vaccination may be modulated by age, further investigations in children and in the elderly as well as on the persistence of the immune response are warranted.


Assuntos
Adjuvantes Imunológicos/farmacologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Adolescente , Adulto , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/imunologia , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Adulto Jovem
10.
J Am Vet Med Assoc ; 228(11): 1757-61, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16740078

RESUMO

OBJECTIVE: To evaluate the efficacy of an adjuvanted modified-live bovine viral diarrhea virus (BVDV) vaccine against challenge with a virulent type 2 BVDV strain in calves with or without maternal antibodies against the virus. DESIGN: Challenge study. ANIMALS: 23 crossbred dairy calves. PROCEDURES: Calves were fed colostrum containing antibodies against BVDV or colostrum without anti-BVDV antibodies within 6 hours of birth and again 8 to 12 hours after the first feeding. Calves were vaccinated with a commercial modified-live virus combination vaccine or a sham vaccine at approximately 5 weeks of age and challenged with virulent type 2 BVDV 3.5 months after vaccination. Clinical signs of BVDV infection, development of viremia, and variation in WBC counts were recorded for 14 days after challenge exposure. RESULTS: Calves that received colostrum free of anti-BVDV antibodies and were vaccinated with the sham vaccine developed severe disease (4 of the 7 calves died or were euthanatized). Calves that received colostrum free of anti-BVDV antibodies and were vaccinated and calves that received colostrum with anti-BVDV antibodies and were vaccinated developed only mild or no clinical signs of disease. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the modified-live virus vaccine induced a strong protective immune response in young calves, even when plasma concentrations of maternal antibody were high. In addition, all vaccinated calves were protected against viral shedding, whereas control calves vaccinated with the sham vaccine shed virus for an extended period of time.


Assuntos
Anticorpos Antivirais/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/prevenção & controle , Vírus da Diarreia Viral Bovina Tipo 2/imunologia , Imunidade Materno-Adquirida , Vacinas Virais/imunologia , Animais , Animais Recém-Nascidos , Anticorpos Antivirais/administração & dosagem , Bovinos , Colostro/imunologia , Feminino , Distribuição Aleatória , Vacinas Atenuadas/imunologia , Virulência
11.
Virus Res ; 120(1-2): 107-12, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16621103

RESUMO

The alphavirus Venezuelan equine encephalitis virus (VEEV) is highly infectious by the airborne route. It is a hazard to laboratory workers, has been developed as a biological weapon and is a potential bioterrorist agent. A suitable vaccine appears in an advanced stage of development but there remains a need for antiviral drugs, effective in prophylaxis of disease prior to or a short time after exposure to airborne virus. Using a murine model to study monoclonal antibody (MAB) a VEEV complex-specific, glycoprotein E2-binding MAB was identified, able to protect against disease induced by exposure to aerosolised VEEV from serogroups I, II and IIIA (mouse-virulent strains). There was no synergy in protection between anti-E1 and anti-E2 MAB. Assays of MAB virus neutralising activity in a homologous (mouse fibroblast) cell line suggested that neutralisation played a significant role in protection in addition to the previously reported mechanism of Fc receptor-binding [Mathews et al., 1985. J. Virol. 55, 594-600]. Development of an analogous human MAB with identical VEEV epitope specificity may be informed and monitored by reference to these properties.


Assuntos
Anticorpos Antivirais/administração & dosagem , Vírus da Encefalite Equina Venezuelana/imunologia , Encefalomielite Equina Venezuelana/prevenção & controle , Imunização Passiva , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Bioterrorismo/prevenção & controle , Células Cultivadas , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos , Fibroblastos , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização
12.
Plant Biotechnol J ; 4(6): 623-31, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17309733

RESUMO

To investigate the potential of antibody derivatives to provide passive protection against enteric infections when supplied orally in crude plant extracts, we have expressed a small immune protein (SIP) in plants using two different plant virus vectors based on potato virus X (PVX) and cowpea mosaic virus (CPMV). The epsilonSIP molecule consisted of a single-chain antibody (scFv) specific for the porcine coronavirus transmissible gastroenteritis virus (TGEV) linked to the epsilon-CH4 domain from human immunoglobulin E (IgE). In some constructs, the sequence encoding the epsilonSIP molecule was flanked by the leader peptide from the original murine antibody at its N-terminus and an endoplasmic reticulum retention signal (HDEL) at its C-terminus to allow the expressed protein to be directed to, and retained within, the endoplasmic reticulum. Western blot analysis of samples from Nicotiana clevelandii or cowpea tissue infected with constructs revealed the presence of SIP molecules which retained their ability to dimerize. The analysis of crude plant extracts revealed that the plant-expressed epsilonSIP molecules could bind to and neutralize TGEV in tissue culture, the levels of binding and neutralization reflecting the level of expression. Oral administration of crude extracts from SIP-expressing plant tissue to 2-day-old piglets demonstrated that the extracts which showed the highest levels of in vitro neutralization could also provide in vivo protection against challenge with TGEV.


Assuntos
Anticorpos Antivirais/imunologia , Gastroenterite Suína Transmissível/imunologia , Vírus da Gastroenterite Transmissível/imunologia , Vacinas Virais/uso terapêutico , Administração Oral , Animais , Anticorpos Antivirais/administração & dosagem , Gastroenterite Suína Transmissível/mortalidade , Vetores Genéticos , Humanos , Imunização Passiva/métodos , Imunoglobulina E/imunologia , Testes de Neutralização , Extratos Vegetais/imunologia , Extratos Vegetais/uso terapêutico , Folhas de Planta/imunologia , Recombinação Genética , Suínos , Vírus da Gastroenterite Transmissível/genética , Vacinas Sintéticas/uso terapêutico
13.
Acta Paediatr ; 87(3): 264-7, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9560031

RESUMO

The efficacy of hyperimmune bovine colostrum received from cows immunized with simian rotavirus SA11 in the treatment of rotavirus gastroenteritis was compared in a randomized double-blind trial to colostrum and ordinary milk preparations. One hundred and thirty-five children aged 6-30 months with rotaviral gastroenteritis received either hyperimmune bovine colostrum (n=42), ordinary colostrum (n=42) or milk (n=41) as a 100 ml solution four times/d for 4 d. Even though the differences were in favour of hyperimmune bovine colostrum in all the variables evaluated [greater weight gain (403 vs 343 g), shorter duration of diarrhoea (3.1 vs 3.6 d), fewer stools during 6 d (11.5 vs 13.6) and fewer stools during the first 3 d (9.3 vs 11.3)], all the differences were statistically insignificant. Differences of this size are clinically unimportant in well-nourished immunocompetent children, but we suggest that the hyperimmune bovine colostrum tested in our trial had some effects in the treatment of acute rotaviral gastroenteritis and should be evaluated further.


Assuntos
Anticorpos Antivirais/administração & dosagem , Colostro/imunologia , Gastroenterite/terapia , Infecções por Rotavirus/terapia , Animais , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Bovinos , Pré-Escolar , Intervalos de Confiança , Método Duplo-Cego , Feminino , Gastroenterite/imunologia , Gastroenterite/virologia , Humanos , Imunização/métodos , Lactente , Masculino , Leite/imunologia , Valores de Referência , Infecções por Rotavirus/imunologia , Resultado do Tratamento
14.
Vaccine ; 15(16): 1767-72, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9364681

RESUMO

We previously found that aqueous-based spermine-alginate or spermine-chondroitin sulfate microcapsules enhanced rotavirus-specific humoral immune responses after intramuscular inoculation of mice. To extend our observations with whole, infectious rotavirus to vaccine strategies which include inactivated virus and purified proteins, we determined the capacity of aqueous-based microcapsules to enhance virus-specific immune responses to bovine herpes virus type 1 glycoprotein D (BHV-1-gD) or ether-treated influenza virus. We found that spermine-alginate microcapsules decreased the quantity of BHV-1-gD necessary to induce protein-specific antibodies about 5000-fold. However, spermine-alginate microcapsules did not enhance influenza virus-specific antibody responses. Microcapsules composed of spermine-chondroitin sulfate did not enhance either BHV-1-gD or influenza virus-specific immune responses. Possible mechanisms of enhancement of virus-specific antibody responses by microencapsulation are discussed.


Assuntos
Vacinas contra Herpesvirus , Vírus da Influenza A/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Alginatos/administração & dosagem , Animais , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Antígenos Virais/imunologia , Cápsulas , Bovinos , Embrião de Galinha , Galinhas , Composição de Medicamentos , Estabilidade de Medicamentos , Feminino , Ácido Glucurônico , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Ácidos Hexurônicos , Camundongos , Espermina/administração & dosagem , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia
15.
Vet Microbiol ; 58(2-4): 105-11, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9453122

RESUMO

The protective effect of egg yolk and colostrum powders prepared from hens and cows vaccinated with inactivated bovine coronavirus (BCV) antigen was evaluated in a challenge model with a virulent BCV strain. Twenty three calves from BCV-free herds were randomly divided into control and several treatment groups. All calves were orally challenged with 1 x 10(9) TCID50 of the virulent Kakegawa strain of BCV at 24 to 36 h after birth. Calves in treatment groups received either egg yolk powder or cow colostrum containing BCV specific antibodies. Daily treatment with these antibody preparations started 6 h until 7 days post-challenge. Control calves which received no antibody had severe diarrhea and all died within 6 days after infection. In contrast, calves fed milk containing egg yolk or colostrum with neutralization titers of 1:2560 or 1:10,240 respectively all survived and had positive weight gain unlike the other treatment groups. These results indicate that the orally administered egg yolk and colostrum powders protected against BCV-induced diarrhea in neonatal calves and that the egg yolk used provided a higher degree of protection compared to colostrum powder on a titer basis. Treatment with whole egg yolk from immunized hens therefore provides a more efficacious alternative to the existing methods of specific passive protection against BCV.


Assuntos
Anticorpos Antivirais/administração & dosagem , Doenças dos Bovinos , Infecções por Coronavirus/veterinária , Coronavirus Bovino , Diarreia/veterinária , Imunização Passiva/veterinária , Animais , Especificidade de Anticorpos , Bovinos , Colostro/virologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Coronavirus Bovino/imunologia , Diarreia/prevenção & controle , Diarreia/virologia , Gema de Ovo , Imunização Passiva/métodos , Testes de Neutralização
16.
J Med Virol ; 38(2): 117-23, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1334126

RESUMO

After immunizing 8-month pregnant Holstein cows with the human rotavirus MO strain, cow colostrum containing neutralizing antibody to four different serotypes of human rotavirus, designated Rota colostrum, was obtained. Oral inoculation of human rotavirus MO strain into 5-day-old BALB/c mice causes gastroenteritis characterized by diarrhea. Using this small animal model, passive protection of suckling mice against human rotavirus infection was achieved with the use of Rota colostrum. Rota colostrum completely protected against rotavirus infection, but purified IgG and IgA obtained from Rota colostrum were unable to protect against infection. After grouping randomly 20 infants from a baby care center, 10 infants received 20 ml of Rota colostrum per day for 2 weeks and 10 control infants did not. Rotavirus-associated diarrhea developed in 7 of 10 infants in the control group. None of the three infants in the every day recipient group of Rota colostrum had such symptoms, and one of three infants in the every other day recipient group developed rotavirus-induced diarrhea. All four infants who received Rota colostrum after symptoms appeared developed diarrhea. Oral administration of Rota colostrum seems to be an effective and safe means of preventing diarrhea caused by human rotavirus infection.


Assuntos
Gastroenterite/prevenção & controle , Imunização Passiva , Infecções por Rotavirus/prevenção & controle , Fatores Etários , Animais , Anticorpos Antivirais/administração & dosagem , Bovinos , Creches , Colostro/imunologia , Feminino , Humanos , Lactente , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Rotavirus/classificação , Rotavirus/imunologia
17.
J Clin Microbiol ; 29(7): 1382-6, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1653265

RESUMO

Rotavirus, a double-stranded RNA virus, has been implicated as a diarrhea-provoking agent in a variety of animal species. Several previous reports have shown that immunization with a single serotype may result in increased in vitro neutralization titers against serotypes not represented in the immunogen. This study was undertaken to determine whether antibody from cows immunized against simian rotavirus strain SA-11 (which is alien to pigs) could protect neonatal piglets from infection with a North Carolina isolate of porcine rotavirus. Accordingly, cows were immunized with SA-11 and an immunoglobulin G (IgG)-rich fraction was isolated from their colostrum. An IgG-rich fraction was similarly isolated from colostrum of nonimmunized cows. At equal concentrations, IgG from SA-11-immunized cows had two- to fourfold higher neutralization titers to seven of eight test strains of rotavirus, including SA-11 (serotype 3); human rotavirus serotypes 1, 3, and 4; North Carolina porcine rotavirus (serotype undetermined); Ohio State porcine rotavirus (serotype 5); and bovine rotavirus (serotype 6). The IgG-rich fractions were fed as dietary supplements to agammaglobulinemic piglets infected with the North Carolina porcine rotavirus. IgG from the SA-11-immunized cows was about eightfold more effective in protecting piglets than was IgG from nonimmunized cows.


Assuntos
Infecções por Rotavirus/veterinária , Doenças dos Suínos/prevenção & controle , Agamaglobulinemia/imunologia , Animais , Anticorpos Antivirais/administração & dosagem , Bovinos , Colostro/imunologia , Imunização , Imunoglobulina G/administração & dosagem , Rotavirus/classificação , Rotavirus/imunologia , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Suínos , Doenças dos Suínos/imunologia
18.
J Virol ; 62(7): 2238-42, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2836607

RESUMO

The effect of circulating passive antibody on immunity to bovine rotavirus infections in neonatal calves was investigated. In the first experiment, rotavirus antibody titers in the small intestinal lumina of 5- and 10-day-old calves with a wide range of serum rotavirus antibody titers were determined. Neutralizing antibody was present in the small intestinal lumina in titers that correlated with the calves' serum titers (r = +0.84, P less than 0.01). Immunoglobulin G1 was the predominant isotype of intestinal luminal rotavirus antibody. Calves not fed colostrum during the absorptive period lacked rotavirus antibody in circulation and in the intestinal lumen at 7 days of age, even when they were fed large volumes of colostrum with a high rotavirus antibody titer at 48 h after birth. Therefore, rotavirus antibody is not retained in the intestinal lumen for 5 days following a colostrum meal, and the luminal antibody in the 5- and 10-day-old seropositive calves were probably derived from circulating antibody. In a second experiment, calves were passively immunized by subcutaneous injection of colostral whey with a high immunoglobulin G1 rotavirus antibody titer and challenged with virulent bovine rotavirus 48 h later. The passively immunized calves were protected from rotavirus infection and diarrhea compared with calves with comparable serum immunoglobulin concentrations but with lower serum rotavirus with lower serum rotavirus antibody titers. The results of these experiments indicate that circulating immunoglobulin G1 antibody appears in the gastrointestinal tract of neonatal calves and that circulating rotavirus antibody can prevent infection and diarrhea after rotavirus challenge.


Assuntos
Anticorpos Antivirais/metabolismo , Bovinos/imunologia , Sistema Digestório/imunologia , Imunização Passiva , Imunoglobulina G/metabolismo , Rotavirus/imunologia , Animais , Animais Recém-Nascidos , Anticorpos Antivirais/administração & dosagem , Bovinos/metabolismo , Colostro/metabolismo , Diarreia/prevenção & controle , Diarreia/veterinária , Sistema Digestório/metabolismo , Conteúdo Gastrointestinal , Imunoglobulina G/administração & dosagem , Injeções Intramusculares , Injeções Subcutâneas , Masculino , Infecções por Rotavirus/prevenção & controle , Infecções por Rotavirus/veterinária
19.
Vet Immunol Immunopathol ; 11(1): 45-63, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3006327

RESUMO

The intestinal and systemic antibody response of calves vaccinated and/or challenged with rotavirus was studied employing isotype-specific ELISAs for the detection of IgG1, IgG2, IgM and IgA antibodies to rotavirus. Monoclonal antibodies to bovine immunoglobulin isotypes of proven specificity were used as conjugated or catching antibody. Five days after oral inoculation (dpi) of a 5-day-old gnotobiotic calf with rotavirus, IgM rotavirus antibodies were excreted in faeces, followed 5 days later by IgA rotavirus antibodies. The increase in IgM rotavirus antibody titre coincided with the inability to detect further rotavirus excretion. Faeces IgM and IgA rotavirus antibody titres fell to low levels within 3 weeks post infection. IgG1 and IgG2 rotavirus antibodies were not detected in faecal samples. In serum, antibodies to rotavirus of all four isotypes were detected, starting with IgM at 5 dpi. Two SPF-calves, which were fed colostrum free of rotavirus antibodies, were vaccinated with a modified live rotavirus vaccine and challenged with virulent rotavirus 6 days later. Upon vaccination, the calves showed an antibody response similar to the response of the infected gnotobiotic calf. Intestinal IgM rotavirus antibodies were excreted before or on the day of challenge and appeared to be associated with protection against challenge infection with virulent virus and rotavirus-induced diarrhoea. In 3 control calves, which were challenged only, the antibody patterns also resembled that of the gnotobiotic calf and again the appearance of IgM rotavirus antibodies coincided with the end of the rotavirus detection period. Two other groups of 3 SPF-calves were treated similarly, but the calves were fed colostrum with rotavirus antibodies during the first 48 h of life. These calves excreted passively acquired IgG1 and IgG2 rotavirus antibodies in their faeces from 2 to 6 days after birth. After vaccination, no IgM or IgA antibody activity in serum or faeces was detectable. Upon challenge, all calves developed diarrhoea and excreted rotavirus. Seven to 10 days after challenge low levels of IgM rotavirus antibody were detected for a short period. These data indicate that the intestinal antibody response of young calves to an enteric viral infection is associated with the excretion of IgM antibodies, immediately followed by IgA antibodies. This response is absent or diminished in calves with passively acquired specific antibodies which may explain the failure to induce a protective intestinal immune response by oral vaccination with modified live rotavirus of calves fed colostrum containing rotavirus antibodies.


Assuntos
Anticorpos Antivirais/biossíntese , Intestinos/imunologia , Infecções por Rotavirus/imunologia , Rotavirus/imunologia , Administração Oral , Fatores Etários , Animais , Animais Recém-Nascidos , Anticorpos Antivirais/administração & dosagem , Bovinos , Colostro/imunologia , Imunização Passiva , Imunoglobulina A/biossíntese , Imunoglobulina G/biossíntese , Imunoglobulina M/biossíntese , Organismos Livres de Patógenos Específicos , Vacinas Virais/administração & dosagem
20.
Med Microbiol Immunol ; 173(2): 87-93, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6493135

RESUMO

Previous virological and immunological studies have suggested that multiple sclerosis (MS) is an auto-immune disease triggered by a virus infection. In order to inhibit the growth of measles virus in the patient's jejunum, we obtained an IgA-rich cow colostrum containing anti-measles lactoglobulin resistant to proteases. This colostrum was orally administered to patients with MS to investigate its effect on the course of the disease. Measles-positive antibody colostrum was orally administered every morning to 15 patients with MS at a daily dosage of 100 ml for 30 days. Similarly, measles-negative antibody (less than 8) control colostrum was orally administered to 5 patients. As a clinical assessment, disability scores developed by the International Federation of Multiple Sclerosis Societies were used. As a result, of 7 high NT titre (512-5120) anti-measles colostrum recipients 5 patients improved and 2 remained unchanged. Among 8 low NT titre (8-32) anti-measles colostrum recipients 5 patients improved and 3 remained unchanged. However, of 5 negative NT titre (less than 8) colostrum recipients 2 patients remained unchanged and 3 worsened. No side-effects were observed in colostrum recipients. These findings suggest the efficacy of orally administered anti-measles colostrum in improving the condition of MS patients (P less than 0.05).


Assuntos
Anticorpos Antivirais/administração & dosagem , Vírus do Sarampo/imunologia , Esclerose Múltipla/terapia , Adolescente , Adulto , Animais , Doenças Autoimunes/etiologia , Bovinos , Colostro/imunologia , Feminino , Humanos , Imunoterapia , Enteropatias/complicações , Masculino , Sarampo/complicações , Pessoa de Meia-Idade , Esclerose Múltipla/etiologia , Gravidez
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