The COVID-19 pandemic highlighted testing inequities in developing countries. Lack of lateral flow test (LFT) manufacturing capacity was a major COVID-19 response bottleneck in low- and middle-income regions. Here we report the development of an open-access LFT for SARS-CoV-2 detection comparable to commercial tests that requires only locally available supplies.
View Article and Find Full Text PDFVaccination is the best strategy to control Paratuberculosis (PTB), which is a significant disease in cattle and sheep. Previously we showed the humoral and cellular immune response induced by a novel vaccine candidate against PTB based on the Argentinian Mycobacterium avium subspecies paratuberculosis (Map) 6611 strain. To improve 6611 immunogenicity and efficacy, we evaluated this vaccine candidate in mice with two different adjuvants and a heterologous boost with a recombinant modified vaccinia Ankara virus (MVA) expressing the antigen 85A (MVA85A).
View Article and Find Full Text PDFThe current pandemic produced by SARS-CoV-2 and its variants represent an example of the one health concept in which humans and animals are components of the same epidemiologic chain. Animal reservoirs of these viruses are thus the focus of surveillance programs, to monitor their circulation and evolution in potentially new hosts and reservoirs. In this work, we report the detection of the SARS-CoV-2 Gamma variant infection in four specimens of Chaetophractus villosus (big hairy armadillo/armadillo peludo) in Argentina.
View Article and Find Full Text PDFParatuberculosis (PTBC) is a chronic intestinal disease of animals caused by Mycobacterium avium paratuberculosis (MAP). MAP infection is diagnosed through indirect tests based on the immune response. The aims of this study were to compare the performance of two milk ELISA for the diagnosis of PTBC and to assess the bulk tank milk (BTM) MAP exposure in dairy cattle in Argentina.
View Article and Find Full Text PDFParatuberculosis is a chronic granulomatous enteritis caused by subsp. that affects a wide variety of domestic and wild animals. It is considered one of the diseases with the highest economic impact on the ruminant industry.
View Article and Find Full Text PDFAlbumin binding ability is a well-characterized feature of many bacteria. To the best of our knowledge, there are no previous reports about this ability among mycobacteria, even when bovine serum albumin (BSA) is a common component of supplements used for the enrichment of synthetic media for mycobacterial growth in vitro and also of buffers used in laboratory techniques. In this work we explored the albumin binding ability of Mycobacterium avium subsp.
View Article and Find Full Text PDFMycobacterium avium subsp. paratuberculosis (MAP) is an important pathogen that causes granulomatous enteritis known as Johne's disease or paratuberculosis (PTB). In this study an experimental model of calves infected with Argentinean isolates of MAP for 180 days was used to provide more data of the early PTB stages.
View Article and Find Full Text PDFDue to the present pandemic situation and the many animal species that are epidemiologically involved, there has been a surge of renewed interest in investigating the coronavirus (CoV) population circulating in wildlife, especially bats and rodents, which are potential reservoirs of new human pathogens. In Argentina, information about the viruses present in these mammals is very limited. To investigate the presence of coronaviruses in this country, we obtained 457 samples from hematophagous, insectivorous, and frugivorous bats and rodents from two regions of Argentina.
View Article and Find Full Text PDFSARS-CoV-2 reverse zoonosis, particularly to domestic animals, and the potential role of infected animals in perpetuating the spread of the virus is an issue of increasing concern. In this case report, we identified the natural infection of two cats by SARS-CoV-2, in Argentina, whose owner had been previously infected by SARS-CoV-2. Viral genetic material was detected in feline oropharyngeal (OP) and rectal (R) swab by RT-qPCR, and sequence analysis revealed that the virus infecting the owner and one cat were genetically similar.
View Article and Find Full Text PDFIn this work, we used a calf ileal loop model to evaluate whether the preincubation of Mycobacterium avium subspecies paratuberculosis (MAP) with antibodies from healthy, MAP-positive or Lipoarabinomannan (LAM) immunized cows could affect the results of infection after 3.5 h. Bacterial load in tissue was assessed by Ziehl-Neelsen and by culture for each loop.
View Article and Find Full Text PDFToxocara cati is one of the causative agents of human toxocariasis. Serological methods are used for diagnosis in paratenic hosts like humans but the humoral immune response triggered by this parasite is unknown. We characterized the humoral immune response to T.
View Article and Find Full Text PDFThe diagnosis of the early stages of paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (Map), is a cumbersome task. In this study, an experimental Map-infection model of calves was used to improve the knowledge of early antibody response and to evaluate different in-house ELISAs in the detection of subclinical paratuberculosis.
View Article and Find Full Text PDFMycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of ruminant paratuberculosis. The aim of this study was to evaluate the biological behavior of different Argentinean strains of MAP in two bovine infection models: macrophage (in vitro) and calf (in vivo) through the evaluation of early immune responses at the peripheral and local levels. Two MAP strains (A and C) were selected taking into account the different patterns of TNF-α and IL-10 secretion displayed by infected bovine macrophages in vitro.
View Article and Find Full Text PDFThe aim of this study was to standardize a diagnosis procedure to detect Mycobacterium avium subsp. paratuberculosis (Map) DNA in raw cow milk samples under field conditions. A procedure that combines both immunomagnetic separation and IS900-PCR detection (IMS-IS1 PCR) was employed on milk samples from 265 lactating Holstein cows from Map infected and uninfected herds in Argentina.
View Article and Find Full Text PDFMycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne's disease (JD), a chronic granulomatous enteritis in ruminants. Understanding the protective immune response following infection is crucial to improve the diagnosis and the development of vaccines against this disease. The goal of this work was to assess whether specific antibodies were able to modulate the macrophage response to MAP infection by evaluating apoptosis and TNF-α secretion in an in vitro model.
View Article and Find Full Text PDFThis study aimed to evaluate the immune response in bovines following immunization with a mycobaterial Lipoarabinomannan extract (LAMe) and the effect of Map challenge. LAMe vaccine induced specific antibody levels that diminished after the challenge and affected Map excretion at least for 100 days thereafter.
View Article and Find Full Text PDFParatuberculosis is an infectious, chronic, and incurable disease that affects ruminants, caused by Mycobacterium avium subsp. paratuberculosis. This bacterium is shed primarily through feces of infected cows but can be also excreted in colostrum and milk and might survive pasteurization.
View Article and Find Full Text PDFParatuberculosis (PTB), or Johne's disease, is a chronic infectious granulomatous enteritis of ruminants, caused by Mycobacterium avium subspecies paratuberculosis (Map). It is characterized by diarrhea and progressive cachexia, which may cause the death of the animal. Calves are the most susceptible to infection.
View Article and Find Full Text PDFJohne's Disease or Paratuberculosis is a chronic granulomatous enteritis disease affecting ruminants. Detection of subclinically infected animals is difficult, hampering the control of this disease. The aim of this work was to evaluate the performance of detection of IgG isotypes in a PPA-ELISA to improve the recognition of cattle naturally infected with Map in different stages.
View Article and Find Full Text PDFLipoarabinomannan (LAM) is a major glycolipidic antigen on the mycobacterial envelope. The aim of this study was to characterize the humoral immune response induced by immunization with a LAM extract in bovines and to evaluate the role of the generated antibodies in the in vitro infection of macrophages with Mycobacterium avium subsp. paratuberculosis (MAP).
View Article and Find Full Text PDFParatuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (Map), is a chronic granulomatous enteric disease in cattle. Among molecular components of Map, protein p34 was identified as specific and immunodominant for bovine B cells.
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