Microvesículas bacterianas secretadas y su potencial uso en el desarrollo de vacunas

Las microvesículas de membrana externa secretadas por bacterias, son estructuras microscópicas, conformadas por parte de la membrana y pared bacteriana, contienen diferentes componentes como proteínas, carbohidratos, lípidos, ácidos nucleicos y otros metabolitos. En el género bacteriano, se describieron inicialmente en bacterias Gram-negativas, sin embargo, de manera reciente se han identificado en las bacterias Gram-positivas. Al principio no se conocía cuál era la composición de estas microvesículas secretadas, sin embargo, debido a los avances en proteómica y genómica han permitido identificar en estas estructuras una amplia variedad de proteínas involucradas en diversas funciones celulares, como la inmunomodulación. También se han identificado ácidos nucleicos como ADN y ARN portando genes codificantes para diferentes factores de adherencia y virulencia. Por esta razón, las microvesículas se han asociado a diversos procesos de patogenicidad, donde algunas proteínas identificadas promueven los procesos de migración, e invasión de bacterias hacia las células del huésped y de esta manera estimulan los procesos de interacción microorganismo-hospedero. Debido a la importante función que tienen estas microvesículas, se ha propuesto utilizarlas como posibles componentes vacúnales en contra de bacterias patógenas. Por lo tanto, en esta revisión se analizan temas importantes como la biogénesis, el contenido intracelular y extracelular asociado a las microvesículas, así como el cargo asociado y su potencial uso para el desarrollo de vacunas a base de microvesículas secretadas

Risk of COVID-19 in Chagas Disease Patients: What Happen with Cardiac Affectations?

Background: Chagas disease is considered a neglected tropical disease. The acute phase of Chagas disease is characterized by several symptoms: fever, fatigue, body aches, headache and cardiopathy’s. Chronic phase could be asymptomatic or symptomatic with cardiac compromise. Since the emergence of the pandemic caused by the SARS-CoV-2 virus, the cardiovascular involvement has been identified as a complication commonly reported in coronavirus disease 2019 (COVID-19). Due to the lack of knowledge of the cardiac affectations that this virus could cause in patients with Chagas disease, the aim of this review is to describe the possible cardiac affectations, as well as the treatment and recommendations that patients with both infections should carry out. Methods: The authors revised the recent and relevant literature concerning the topic and discussed advances and limitations of studies on COVID-19 and their impact in Chagas disease patients, principally with cardiac affectations. Results: There currently exists little information about the consequences that Chagas disease patients can suffer when they are infected with COVID-19. Conclusions: This review highlights the emerging challenges of access to medical care and future research needs in order to understand the implications that co-infections (SARS-CoV-2 or other viruses) can generate in Chagas disease-infected people

Consensus Enolase of Trypanosoma Cruzi: Evaluation of Their Immunogenic Properties Using a Bioinformatics Approach

There is currently no vaccine against American trypanosomiasis, caused by the parasite Trypanosoma cruzi. This is due to the genomic variation observed in the six DTUs of T. cruzi. This work aims to propose a consensus sequence of the enolase protein from different strains of T. cruzi and mainly evaluate its immunogenic properties at the bioinformatic level. From specialized databases, 15 sequences of the enolase gene were aligned to obtain a consensus sequence, where this sequence was modeled and then evaluated and validated through different bioinformatic programs to learn their immunogenic potential. Finally, chimeric peptides were designed with the most representative epitopes. The results showed high immunogenic potential with six epitopes for MHC-I, and seven epitopes for MHC-II, all of which were highly representative of the enolase present in strains from the American continent as well as five epitopes for B cells. Regarding the computational modeling, molecular docking with Toll-like receptors showed a high affinity and low constant of dissociation, which could lead to an innate-type immune response that helps to eliminate the parasite. In conclusion, the consensus sequence proposed for enolase is capable of providing an ideal immune response; however, the experimental evaluation of this enolase consensus and their chimeric peptides should be a high priority to develop a vaccine against Chagas disease

A review on SERS-based detection of human virus infections: influenza and coronavirus

"The diagnosis of respiratory viruses of zoonotic origin (RVsZO) such as influenza and coronaviruses in humans is crucial, because their spread and pandemic threat are the highest. Surface–enhanced Raman spectroscopy (SERS) is an analytical technique with promising impact for the point–of–care diagnosis of viruses. It has been applied to a variety of influenza A virus subtypes, such as the H1N1 and the novel coronavirus SARS−CoV−2. In this work, a review of the strategies used for the detection of RVsZO by SERS is presented. In addition, relevant information about the SERS technique, anthropozoonosis, and RVsZO is provided for a better understanding of the theme. The direct identification is based on trapping the viruses within the interstices of plasmonic nanoparticles and recording the SERS signal from gene fragments or membrane proteins. Quantitative mono- and multiplexed assays have been achieved following an indirect format through a SERS-based sandwich immunoassay. Based on this review, the development of multiplex assays that incorporate the detection of RVsZO together with their specific biomarkers and/or secondary disease biomarkers resulting from the infection progress would be desirable. These configurations could be used as a double confirmation or to evaluate the health condition of the patient"

Experimental Vaccines against Chagas Disease: A Journey through History

Chagas disease, or American trypanosomiasis, which is caused by the protozoan parasite Trypanosoma cruzi, is primarily a vector disease endemic in 21 Latin American countries, including Mexico. Although many vector control programs have been implemented, T. cruzi has not been eradicated. The development of an anti-T. cruzi vaccine for prophylactic and therapeutic purposes may significantly contribute to the transmission control of Chagas disease. Immune protection against experimental infection with T. cruzi has been studied since the second decade of the last century, and many types of immunogens have been used subsequently, such as killed or attenuated parasites and new DNA vaccines. This primary prevention strategy appears feasible, effective, safe, and inexpensive, although problems remain. The objective of this review is to summarize the research efforts about the development of vaccines against Chagas disease worldwide. A thorough literature review was conducted by searching PubMed with the terms “Chagas disease” and “American trypanosomiasis” together with “vaccines” or “immunization”. In addition, reports and journals not cited in PubMed were identified. Publications in English, Spanish, and Portuguese were reviewed