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Background Neurocysticercosis (NCC), and cystic echinococcosis (CE) are two neglected diseases caused by cestodes, co-endemic in many areas of the world. Imaging studies and serological tests are used in the diagnosis of both parasitic diseases, but cross-reactions may confound the results of the latter. The novel multiplex bead-based assay with recombinant antigens has been reported to increases the diagnostic accuracy of serological techniques. Methodology We set-up an immunoassay based on the multiplex bead-based platform (MBA), using the rT24H (against Cysticercus cellulosae, causing cysticercosis) and r2B2t (against Echinococcus granulosus sensu lato, causing CE) recombinant antigens, for simultaneous and differential diagnosis of these infections. The antigens were tested on 356 sera from 151 patients with CE, 126 patients with NCC, and 79 individuals negative for both diseases. Specificity was calculated including sera from healthy donors, other neurological diseases and the respective NCC or CE sera counterpart. The diagnostic accuracy of this assay was compared with two commercial ELISA tests, Novalisa and Ridascreen, widely used in the routine diagnosis of cysticercosis and CE, respectively. Main findings For the diagnosis of NCC, sensitivity ranged from 57.94–63.49% for the rT24H-MBA, and 40.48–46.03% for Novalisa ELISA depending on exclusion or inclusion of sera having equivocal results on ELISA from the analysis; specificities ranged from 90.87–91.30% and 70.43–76.96%, respectively. AUC values of the ROC curve were 0.783 (rT24H) and 0.619 (Novalisa) (p-value < 0.001). For the diagnosis of CE, the sensitivity of the r2B2t-MBA ranged from 68.87–69.77% and of Ridascreen ELISA from 50.00–57.62%; specificities from 92.47–92.68% and from 74.15–80.98%, respectively. AUC values were 0.717 and 0.760, respectively. Conclusions/Significance Overall, the recombinant antigens tested with the bead-based technology showed better diagnostic accuracy than the commercial assays, particularly for the diagnosis of NCC. The possibility of testing the same serum sample simultaneously for the presence of antibodies against both antigens is an added value particularly in seroprevalence studies for cysticercosis linked to control programs in endemic areas where these two parasites coexist. Author summary Cysticercosis and cystic echinococcosis are caused by infection with the larval stages of Taenia solium and Echinococcus granulosus sensu lato, respectively, and their distribution largely overlaps in many areas of the world. Currently, the WHO is calling for the need to map endemic areas for cysticercosis, where control programs should be applied. Serosurveys may serve this scope, but cross-reactivities may be an issue. This study evaluated the accuracy of two recombinant antigens (rT24H and r2B2t) specific for each parasite used together applying a novel multiple bead technology assay (MBA), and compared the results with two commercial ELISA tests for the diagnosis of these infections. We found that this method, although not 100% specific, provides better results than those obtained with the commercially available tests, with the added advantage of testing simultaneously for both infections using just one sample, and could prove an efficient and rapid support for serological screening studies to map areas of cysticercosis transmission. Importantly, this novel method based on MBA technology is open and flexible, allowing continuous improvement due to its ability to simultaneously introduce new recombinant antigens as they are discovered/defined.

Reelin is an extracellular glycoprotein that modulates neuronal function and synaptic plasticity in the adult brain. Decreased levels of Reelin activity have been postulated as a key factor during neurodegeneration in Alzheimer’s disease (AD) and in aging. Thus, changes in levels of full-length Reelin and Reelin fragments have been revealed in cerebrospinal fluid (CSF) and in post-mortem brains samples of AD patients with respect to non-AD patients. However, conflicting studies have reported decreased or unchanged levels of full-length Reelin in AD patients compared to control (nND) cases in post-mortem brains and CSF samples. In addition, a compelling analysis of Reelin levels in neurodegenerative diseases other than AD is missing. In this study, we analyzed brain levels of RELN mRNA and Reelin protein in post-mortem frontal cortex samples from different sporadic AD stages, Parkinson’s disease with dementia (PDD), and Creutzfeldt-Jakob disease (sCJD), obtained from five different Biobanks. In addition, we measured Reelin protein levels in CSF samples of patients with mild cognitive impairment (MCI), dementia, or sCJD diagnosis and a group of neurologically healthy cases. The results indicate an increase in RELN mRNA in the frontal cortex of advanced stages of AD and in sCJD(I) compared to controls. This was not observed in PDD and early AD stages. However, Reelin protein levels in frontal cortex samples were unchanged between nND and advanced AD stages and PDD. Nevertheless, they decreased in the CSF of patients with dementia in comparison to those not suffering with dementia and patients with MCI. With respect to sCJD, there was a tendency to increase in brain samples in comparison to nND and to decrease in the CSF with respect to nND. In conclusion, Reelin levels in CSF cannot be considered as a diagnostic biomarker for AD or PDD. However, we feel that the CSF Reelin changes observed between MCI, patients with dementia, and sCJD might be helpful in generating a biomarker signature in prodromal studies of unidentified dementia and sCJD.

Recent records of bird species in the Colombian Andes have shown that this region is not as well known as was previously believed. We compiled data from a major collection of Colombian birds and from our recent field observations to complement the bird species list of Quindío department. We report the addition of 14 species to Quindío’s checklist and data of museum vouchers for 12 species reported only from field observations. The majority of additions were from localities below 1,900 m above sea level, a zone that has been highly transformed by human activities. Our dataset, and other information, raised the number of bird species in Quindío to 560. This information must be considered in decisions about the land use in this region of the Colombian Andes.