Recombinant multiepitope proteins expressed in Escherichia coli cells and their potential for immunodiagnosis.

Recombinant multiepitope proteins (RMPs) are a promising alternative for application in diagnostic tests and, given their wide application in the most diverse diseases, this review article aims to survey the use of these antigens for diagnosis, as well as discuss the main points surrounding these antigens. RMPs usually consisting of linear, immunodominant, and phylogenetically conserved epitopes, has been applied in the experimental diagnosis of various human and animal diseases, such as leishmaniasis, brucellosis, cysticercosis, Chagas disease, hepatitis, leptospirosis, leprosy, filariasis, schistosomiasis, dengue, and COVID-19. The synthetic genes for these epitopes are joined to code a single RMP, either with spacers or fused, with different biochemical properties. The epitopes' high density within the RMPs contributes to a high degree of sensitivity and specificity. The RMPs can also sidestep the need for multiple peptide synthesis or multiple recombinant proteins, reducing costs and enhancing the standardization conditions for immunoassays. Methods such as bioinformatics and circular dichroism have been widely applied in the development of new RMPs, helping to guide their construction and better understand their structure. Several RMPs have been expressed, mainly using the Escherichia coli expression system, highlighting the importance of these cells in the biotechnological field. In fact, technological advances in this area, offering a wide range of different strains to be used, make these cells the most widely used expression platform. RMPs have been experimentally used to diagnose a broad range of illnesses in the laboratory, suggesting they could also be useful for accurate diagnoses commercially. On this point, the RMP method offers a tempting substitute for the production of promising antigens used to assemble commercial diagnostic kits.

Molecular methods for diagnosis of monkeypox: A mini-review.

BACKGROUND: Monkeypox is a global public health issue caused by the monkeypox virus (MPXV). As of October 28, 2022, a total of 77,115 laboratory-confirmed cases and 3,610 probable cases, including 36 deaths, were reported, with 9,070 cases reported in Brazil, the second most affected country. The need to develop national technologies for the rapid diagnosis of emerging diseases for mass testing of the population is evident, as observed in the SARS-CoV-2 pandemic. OBJECTIVE: With that in mind, this article provides an overview of current methods, techniques, and their applications in the molecular detection of monkeypox, focusing the search on real-time polymerase chain reaction (qPCR), polymerase chain reaction (PCR), and polymerase chain reaction-enzyme linked immunosorbent assay (PCR-ELISA). METHODS: The relevant documents or papers covered in this study were selected by a search in international bibliographic databases. The search terms used in the databases were aimed at summarizing existing knowledge on molecular diagnostic methods, such as monkeypox; MPX, MPXV, qPCR, PCR, PCR-ELISA, diagnosis and detection searched separately or together using the Boolean operator "AND" either in the title or abstract. The searches took place in September 2022, and the corresponding articles were selected between 2012 and 2022. RESULTS: We found 256 documents in total and twelve studies addressing the molecular diagnosis of monkeypox were classified as possible sources for this review. CONCLUSION: It is evident there is a pressing need to develop national technologies for rapid diagnosis of emerging diseases for mass testing of the population. It is also extremely important to have national detection kits with greater diagnostic capacity to assist in developing effective public policies in countries affected by this disease.

A Mini-review on Potentials Proteins/Peptides Applied for Serodiagnosis of Human Monkeypox Infection and Future Trends.

Monkeypox is a zoonosis that re-emerged in 2022, generating cases in non-endemic countries for the disease and creating a public health issue. The rapid increase in the number of cases kindles a need for quick, inexpensive diagnostic tests for the epidemiological control of the disease. The high cost of molecular tests can make this control more difficult to access in poorer regions, with immunological tests being a more viable option. In this mini-review, a search was conducted in the main databases for peptide and protein options that could be used in the development of serological diagnostic tests. Nine viable registres were found, and seven were selected (two patents and five studies). The main studies used the B21R peptide sequence as it is a high immunogenic epitope. In addition, studies on the improvement of these sequences were also found to avoid cross-reactions against other viruses of the same family, proposing a rational approach using multiepitope recombinant proteins. These approaches demonstrated high sensitivity and specificity values and are seen as viable options for developing new tests. New effective serological testing options, when combined with awareness, disease surveillance, early diagnosis, and rapid communication, form a set of key strategies used by health systems to control the spread of the monkeypox virus.

Proof of Concept of a Novel Multiepitope Recombinant Protein for the Serodiagnosis of Patients with Chagas Disease.

Chagas disease remains a neglected disease that is considered to be a public health problem. The early diagnosis of cases is important to improve the prognosis of infected patients and prevent transmission. Serological tests are the method of choice for diagnosis. However, two serological tests are currently recommended to confirm positive cases. In this sense, more sensitive and specific serological tests need to be developed to overcome these current diagnosis problems. This study aimed to develop a new recombinant multiepitope protein for the diagnosis of Chagas disease, hereafter named rTC. The rTC was constructed based on amino acid sequences from different combinations of Trypanosoma cruzi antigens in the same polypeptide and tested using an enzyme-linked immunosorbent assay (ELISA) to detect different types of Chagas disease. rTC was able to discriminate between indeterminate (IND) and cardiac (CARD) cases and cross-reactive diseases, as well as healthy samples, with 98.28% sensitivity and 96.67% specificity, respectively. These data suggest that rTC has the potential to be tested in future studies against a larger serological panel for the diagnosis of Chagas disease.

A Biotechnological Review on Patents Applied to Rubella Diagnosis.

BACKGROUND: Rubella, caused by the Rubella virus (RV), is considered a mild self-limited illness. However, RV has teratogenic potential. Laboratory investigation plays an important role in both diagnosis and surveillance of the disease. The main methods for diagnosing Rubella are serological assays for the detection of specific IgM and molecular assays for detecting viral RNA. However, some laboratories perform IgG avidity testing, virus isolation and analysis of genetic sequence as tools to help Rubella eradication. The importance of the diagnosis of Rubella involves the appropriate treatment of the disease, because the Rubella clinical symptoms may be similar to those of other diseases, and the population monitoring to avoid new emergent cases. This study addresses different methods of diagnosing Rubella and contributes as a source of knowledge to assist health systems in controlling the disease. OBJECTIVE: The main objective of this study was to review the available patents regarding Rubella diagnosis published in intellectual property databases, and provides an overview of the technologies available for the diagnosis of Rubella. METHOD: The search strategy was based on the keywords searched separately or together using a Boolean operator either in the patent title or abstract the time interval was restricted to patents filed or granted from January 2009 until February 2022. The database used was Google Patents. RESULTS: This study analyzed 24 patent documents regarding strategies for the diagnosis of Rubella. Of these, 15 patents disclose strategies for detecting Rubella antibodies, 7 patents the detection of Rubella virus nucleic acid, and 2 patents the production of antibodies applied in Rubella diagnosis. CONCLUSION: Rubella is still a public health problem in some countries, mainly those in development, especially due to congenital Rubella syndrome, which can cause malformation or fetal death. However, its diagnosis is challenging, due to similarity of symptoms with other diseases, and for this reason, laboratory diagnosis is essential. Studies like this encourage researchers and governments to invest in research to continue the development of new products, using different areas of biotechnology, to solve society's problems, especially diseases that have an impact on global health, such as Rubella.