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Rocky Mountain or Brazilian spotted fever, caused by Rickettsia rickettsii, is a fulminant, seasonal, and neglected disease that occurs in focal points of North America and South America. Its rapid detection is essential for the better prognosis and survival rate of infected individuals. However, disease diagnosis still faces challenges as the accuracy of many of the available laboratory tests fluctuates. This review aimed to analyze methods for antibody or antigen detection, their gaps, and their evolution over time. A search was conducted to find all studies in the Pubmed database that described the antibody or antigen detection of R. rickettsii infections. Initially, a total of 403 articles were screened. Of these articles, only 17 fulfilled the pre-established inclusion criteria and were selected. Among the different methods applied, the IFA technique was the one most frequently found in the studies. However, it presented varied results such as a low specificity when using the indirect method. Other techniques, such as ELISA and immunohistochemistry, were also found, although in smaller numbers and with their own limitations. Although some studies showed promising results, there is a pressing need to find new techniques to develop a rapid and effective diagnosis of R. rickettssi infection.

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INTRODUCTION: Active targeting of tumors by nanomaterials favors early diagnosis and the reduction of harsh side effects of chemotherapeuticals. METHOD: We synthesized magnetic nanoparticles (64 nm; -40 mV) suspended in a magnetic fluid (MF) and decorated them with anti-carcinoembryonic antigen (MFCEA; 144 nm; -39 mV). MF and MFCEA nanoparticles were successfully radiolabeled with technetium-99m (99mTc) and intravenously injected in CEA-positive 4T1 tumor-bearing mice to perform biodistribution studies. Both 99mTc-MF and 99mTc-MFCEA had marked uptake by the liver and spleen, and the renal uptake of 99mTc-MFCEA was higher than that observed for 99mTc-MF at 20h. At 1 and 5 hours, the urinary excretion was higher for 99mTc-MF than for 99mTc-MFCEA. RESULTS: These data suggest that anti-CEA decoration might be responsible for a delay in renal clearance. Regarding the tumor, 99mTc-MFCEA showed tumor uptake nearly two times higher than that observed for 99mTc-MFCEA. Similarly, the target-nontarget ratio was higher with 99mTc-MFCEA when compared to the group that received the 99mTc-MF. CONCLUSION: These data validated the ability of active tumor targeting by the as-developed antiCEA loaded nanoparticles and are very promising results for the future development of a nanodevice for the management of breast cancer and other types of CEA-positive tumors.

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BACKGROUND: schistosomiasis is a neglected tropical parasitic disease caused by trematode worms of the genus schistosoma, which affects approximately 240 million people worldwide. the diagnosis of the disease can be performed by parasitological, molecular, and/or immunological methods, however, the development of new diagnostic methods still essential to guide policy decisions, monitor disease trends and assess the effectiveness of interventions. OBJECTIVE: in this sense, the current work summarizes the findings of a systematic review regarding antigens applied in the enzyme-linked immunosorbent assay test, which were patented and published over the last ten years. METHODS: the literature search strategy used medical subject heading (mesh) terms to define as descriptors. "schistosoma mansoni" was used in arrangement with the descriptors "immunoassay", "enzyme-linked immunosorbent assay", "elisa", and "antigens", using the "and" connector. the patent search was done using keywords, including diagnosis and schistosoma or schistosomiasis or schistosome. several databases were employed for the patent search, such as intellectual property national institute; european patent office; the united states patent and trademark office; patent scope, and google patents. RESULTS: forty-one articles were retrieved, of which only five met the eligibility criteria. seventeen patents were taken from the databases, and a brief description of the most relevant inventions is given here. CONCLUSION: schistosomiasis is considered the most important helminthic disease in worldwide. therefore, it is important to of searching for and develops diagnostic methods based on serology to reduce morbidity and mortality caused by the disease.

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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.

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BACKGROUND: visceral leishmaniasis (VL) is a critical public health problem in over ninety countries. The control measures adopted in Brazil have been insufficient when it comes to preventing the spread of this overlooked disease. In this context, a precise diagnosis of VL in dogs and humans could help to reduce the number of cases of this disease. Distinct studies for the diagnosis of VL have used single recombinant proteins in serological assays; however, the results have been variable, mainly in relation to the sensitivity of the antigens. In this context, the development of multiepitope-based proteins could be relevant to solving such problem. METHODS: a chimeric protein (rMELEISH) was constructed based on amino acid sequences from kinesin 39 (k39), alpha-tubulin, and heat-shock proteins HSP70 and HSP 83.1, and tested in enzyme-linked immunosorbent (ELISA) for the detection of L. infantum infection using canine (n = 140) and human (n = 145) sera samples. RESULTS: in the trials, rMELEISH was able to discriminate between VL cases and cross-reactive diseases and healthy samples, with sensitivity and specificity values of 100%, as compared to the use of a soluble Leishmania antigenic extract (SLA). CONCLUSIONS: the preliminary data suggest that rMELEISH has the potential to be tested in future studies against a larger serological panel and in field conditions for the diagnosis of canine and human VL.

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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.

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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.

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Systemic therapy is generally required for breast cancer. However, treatment toxicity and side effects are a concern, especially for triple-negative breast cancer (TNBC), a subtype that usually develops resistance to chemotherapy. To overcome this issue, new nanoformulations capable of targeting cancer cells have been developed and alternative biomarkers have been explored as target molecules for TNBC management. In this study, we performed anin vivoassay in a murine orthotopic TNBC model to evaluate the targeting ability of anti-carcinoembryonic antigen (anti-CEA) loaded nanoparticles (labelled MFCEA), which had been previously synthetized by our research group. 4T1 cells were injected in the mammary gland of balb-c mice, and tumors were evaluated for CEA expression by immunohistochemistry. Tumor-bearing mice received targeted (MFCEA) and non-targeted (MF) nanoparticles intraperitoneally. Tumors were removed 1, 4, 15 and 24 h after treatment, and Prussian blue iron staining was performed. Our results showed, as far as we know for the first time, that 4T1 induced tumors are CEA positive, and this opens up new prospects for treating TNBC. Furthermore, MFCEA nanoparticles were able to target malignant tissue and were retained in the tumor for longer than MF nanoparticles. The retention property of MFCEA, together with the absence of toxicity observed in the MTT assay, make these nanoparticles a promising device for management of CEA positive tumors and perhaps for TNBC. Nevertheless, further studies must be carried out to improve their performance and ensure safety for clinical studies.

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Canine leishmaniosis (CanL) is one of the most important parasitic diseases found in several countries worldwide. Dogs are considered important domestic reservoirs of the parasites, being relevant in the maintenance of transmission cycle of the disease between sandflies and humans. However, the prevalence of asymptomatic infection is considerably higher than that of apparent clinical illness in the infected animals; thus making promptly necessary to diagnose the infection in these animals, which could help to allow to the adoption of more efficient control measures against disease. Parasitological tests, which are considered as gold standard to demonstrate the infection and diagnose the disease, present problems related with their sensitivity. Also, the sample´s collect is considered invasive. As consequence, serological tests could be applied as an additional tool to detect the asymptomatic and symptomatic CanL. For this purpose, distinct recombinant antigens have been studied; however, problems in their sensitivity and/or specificity have been still registered. The present review focus in advances in the identification of new diagnostic targets applied for the CanL diagnose, represented here by recombinant single, combined or chimeric proteins, as well as by peptides that mimic epitopes (mimotopes); which were selected by means of immunoproteomics and phage display.

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BACKGROUND: The Human Cytomegalovirus (HCMV) has infected more than 90% of the world population and its prevalence can be related to the individuals geographical and socialeconomic status. Serological tests based on ELISA are pivotal for HCMV diagnosis. Due to the lack of standardization in the production/purification of antigens from viral preparations, ELISA tests are based on several recombinant proteins or peptides. As an alternative, multiepitope proteins may be employed. OBJECTIVE: In this work, we developed a recombinant multiepitope protein (rMEHCMV) for HCMV diagnosis based on conserved and immunodominant epitopes derived from tegument (pp150, pp65 and pp28), glycoprotein gB (pp38) and DNA polymerase subunit (pp52) of HCMV. METHODS: The rMEHCMV gene was synthesized de novo and overexpressed in Escherichia coli cells. The recombinant protein was purified to homogeneity using a Ni-NTA column. Biophysical analysis of recombinant protein was performed by circular dichroism. A preliminary biological activity test was performed using 12 positive human sera samples by using an in-house IgG ELISA. The following patents database were consulted: Espacenet, Google Patents and the National Institute of Intellectual Property (INPI, Brazil). RESULTS: The recombinant multiepitope protein was successfully expressed in E. coli. The structural data obtained by circular dichroism spectroscopy showed that rMEHCMV is structurally disordered. An in-house IgG ELISA test with rMEHCMV was successfully used to recognized IgG from human serum samples. CONCLUSION: Together, our results show that rMEHCMV should be considered as a potential antigenic target for HCMV diagnosis.

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