All healthy humans have high levels of natural anti-α-galactosyl (α-Gal) antibodies (elicited by yet uncharacterized glycotopes), which may play important roles in immunoglycomics: (a) potential protection against certain parasitic and viral zoonotic infections; (b) targeting of α-Gal-engineered cancer cells; (c) aiding in tissue repair; and (d) serving as adjuvants in α-Gal-based vaccines. Patients with certain protozoan infections have specific anti-α-Gal antibodies, elicited against parasite-derived α-Gal-bearing glycotopes. These glycotopes, however, remain elusive except for the well-characterized glycotope Galα1,3Galβ1,4GlcNAcα, expressed by Trypanosoma cruzi . The discovery of new parasitic glycotopes is greatly hindered by the enormous structural diversity of cell-surface glycans and the technical challenges of classical immunoglycomics, a top-down approach from cultivated parasites to isolated glycans. Here, we demonstrate that reversed immunoglycomics, a bottom-up approach, can identify parasite species-specific α-Gal-bearing glycotopes by probing synthetic oligosaccharides on neoglycoproteins. This method was tested here seeking to identify as-yet unknown glycotopes specific for Leishmania major , the causative agent of Old-World cutaneous leishmaniasis (OWCL). Neoglycoproteins decorated with synthetic α-Gal-containing oligosaccharides derived from L. major glycoinositolphospholipids served as antigens in a chemiluminescent enzyme-linked immunosorbent assay using sera from OWCL patients and noninfected individuals. Receiver-operating characteristic analysis identified Gal p α1,3Gal f β and Gal p α1,3Gal f β1,3Man p α glycotopes as diagnostic biomarkers for L. major- caused OWCL, which can distinguish with 100% specificity from heterologous diseases and L. tropica- caused OWCL. These glycotopes could prove useful in the development of rapid α-Gal-based diagnostics and vaccines for OWCL. Furthermore, this method could help unravel cryptic α-Gal-glycotopes of other protozoan parasites and enterobacteria that elicit the natural human anti-α-Gal antibodies.

BackgroundPhlebotomus (Larroussius) guggisbergi is among the confirmed vectors for cutaneous leishmaniasis (CL) transmission in Kenya. This scarring and stigmatizing form of leishmaniasis accounts for over one million annual cases worldwide. Most recent CL epidemics in Kenya have been reported in Gilgil, Nakuru County, where the disease has become a public health issue. However, little is known about the factors that drive its transmission. Here, we sought to determine the occurrence, distribution and host blood feeding preference of the vectors, and to identify Leishmania species and infection rates in sandflies using molecular techniques. This information could lead to a better understanding of the disease transmission and improvement of control strategies in the area.Methodology/ Principal findingsAn entomological survey of sandflies using CDC light traps was conducted for one week per month in April 2016, and in June and July 2017 from five villages of Gilgil, Nakuru county; Jaica, Sogonoi, Utut, Gitare and Njeru. Sandflies were identified to species level using morphological keys and further verified by PCR analysis of cytochrome c oxidase subunit I (COI) gene. Midguts of female sandflies found to harbour Leishmania were ruptured and the isolated parasites cultured in Novy-MacNeal-Nicolle (NNN) media overlaid with Schneider’s insect media to identify the species. Leishmania parasite screening and identification in 198 randomly selected Phlebotomus females and parasite cultures was done by PCR-RFLP analysis of ITS1 gene, nested kDNA-PCR and real-time PCR-HRM followed by sequencing. Bloodmeal source identification was done by real-time PCR-HRM of the vertebrate cytochrome-b gene. A total of 729 sandflies (males: n = 310; females: n = 419) were collected from Utut (36.6%), Jaica (24.3%), Sogonoi (34.4%), Njeru (4.5%), and Gitare (0.1%). These were found to consist of nine species: three Phlebotomus spp. and six Sergentomyia spp. Ph. guggisbergi was the most abundant species (75.4%, n = 550) followed by Ph. saevus sensu lato (11.3%, n = 82). Sandfly species distribution across the villages was found to be significantly different (p<0.001) with Jaica recording the highest diversity. The overall Leishmania infection rate in sandflies was estimated at 7.07% (14/198). Infection rates in Ph. guggisbergi and Ph. saevus s.l. were 9.09% (12/132) and 3.57% (2/56) respectively. L. tropica was found to be the predominant parasite in Gilgil with an overall infection rate of 6.91% (13/188) in Ph. guggisbergi (n = 11) and Ph. saevus s.l. (n = 2) sandflies. However, PCR analysis also revealed L. major infection in one Ph. guggisbergi specimen. Bloodmeal analysis in the 74 blood-fed sandflies disclosed a diverse range of vertebrate hosts in Ph. guggisbergi bloodmeals, while Ph. saevus s.l. fed mainly on humans.Conclusions/ SignificanceThe high infection rates of L. tropica and abundance of Ph. guggisbergi in this study confirms this sandfly as a vector of L. tropica in Kenya. Furthermore, isolation of live L. tropica parasites f...

Background In the Kingdom of Saudi Arabia (KSA), Leishmania major and L. tropica are the main causative agents of Old World cutaneous leishmaniasis (CL). The national CL treatment regimen consists of topical 1% clotrimazole/2% fusidic acid cream followed by 1–2 courses of intralesional sodium stibogluconate (SSG); however, treatment efficacy is highly variable and the reasons for this are not well understood. In this study, we present a complete epidemiological map of CL and determined the efficacy of the standard CL treatment regime in several endemic regions of KSA. Results Overall, three quarters of patients in all CL-endemic areas studied responded satisfactorily to the current treatment regime, with the remaining requiring only an extra course of SSG. The majority of unresponsive cases were infected with L. tropica . Furthermore, the development of secondary infections (SI) around or within the CL lesion significantly favoured the treatment response of L. major patients but had no effect on L. tropica cases. Conclusions The response of CL patients to a national treatment protocol appears to depend on several factors, including Leishmania parasite species, geographical location and occurrences of SI. Our findings suggest there is a need to implement alternative CL treatment protocols based on these parameters. Electronic supplementary material The online version of this article (10.1186/s13071-019-3453-4) contains supplementary material, which is available to authorized users.

The antimicrobial activity, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) of TQ were determined using an agar well diffusion method and broth microdilution assays, and the synergistic effect was evaluated using antibiotics in parallel. The disruptive effect of TQ on bacterial cell membranes was determined using scanning electron microscopy. The antivirulence Original Article properties of TQ, which include adherence and biofilm formation, were also investigated using adherence and biofilm formation assays, respectively. Results: Thymoquinone demonstrated bactericidal efficacy against 4/14 bacterial strains, with MIC range of 1.04-8.3 μg/mL and and MBC range of 10.41-66.66 μg/ mL. Thymoquinone showed synergism against Klebsiella pneumoniae, Staphylococcus epidermidis (American Type Culture Collection 12228), Staphylococcus aureus, and Staphylococcus epidermidis in combination with the tested antibiotics. Thymoquinone inhibited bacterial adhesion by 39%-54%, 48%-68%, and 61%-81% at 0.5 × MIC, 1 × MIC, and 2 × MIC, respectively. The tested bacterial strains significantly inhibited biofilm formation after treatment with various concentrations of TQ for 24 and 48 hours. Conclusion: The combinatory effect of TQ with antimicrobials should be considered when developing new antimicrobial therapy regimens to overcome multidrugresistant.

Lactobacillus (LAB) genera are considered important functional food but are found to have a short shelf life. In this study, two LAB, Lactobacillus plantarum (Lp) and Lactobacillus rhamnosus (Lr), were isolated from sheep’s milk, and whole-genome sequencing was carried out by using 16s rRNA Illumina Nextseq, the Netherlands. The LAB were encapsulated by the lyophilisation technique using different lyoprotective pharmaceutical excipients. This process was carried out using a freeze dryer (U-TECH, Star Scientific Instruments, India). Shelf-life determination was carried out by a 12-month study using the viability survival factor (Vsf). The in vitro cell adhesion technique was carried out by using the red snapper fish along with autoaggregation and cell surface hydrophobicity as vital probiotic properties. It was observed that Lp has a significantly higher (P < 0.001) Vsf of 7.2, while Lr has a Vsf of 7 (P < 0.05) when both are encapsulated with 10% maltodextrin + 5% sucrose kept at 4°C for 12 months. The result demonstrated that Lp had significantly high (P < 0.05) cell adhesion, 96% ± 1.2 autoaggregation, and 6% cell surface hydrophobicity as compared to Lr. Moreover, this study demonstrated that lyophilised LAB with lyoprotective excipients enhances shelf life without any changes in probiotic properties when kept at 4°C exhibiting all its probiotic properties.

Background: Dogs can act as reservoirs of canine leishmaniasis, caused by Leishmania species. The aims of this study were to determine the prevalence of canine leishmaniasis using a PCR technique among stray dogs living in three provinces of Saudi Arabia, Riyadh, Al-Ahsa Oasis and Al-Qaseem, where the disease is endemic; and to identify and document different Leishmania to species levels Methods: This cross-sectional investigation was conducted, from Mar 2016 to Apr 2018, in three parts of Saudi Arabia: Central province (Riyadh), Eastern province (Al-Ahsa Oasis) and Al-Qaseem province. Blood samples were collected from 526 dogs; 40 presented cutaneous nodules so were suspected clinically of cutaneous leishmaniasis. Biopsy tissue collections and parasite cultures were performed. A generic kDNA was performed using different primers for Leishmania differentiation. Results: All blood samples were negative for Leishmania infantum infection by molecular analysis, though forty dogs had thick cutaneous lesions in different parts of their body. Four dogs’ skin lesions were associated with dermatitis, splenomegaly and lymphadenomegaly. Parasite culture was used to diagnose cutaneous leishmaniasis, identifying 31/40 (77.5%) positive samples. Overall, of 526 samples, the prevalence of L. major and L. tropica was found to be 4% and 1.9%, respectively. Gender and age had a significant effect on Leishmania prevalence: (P=0.0212 and 0.0357), respectively. Conclusion: This was the first molecular study of dog leishmaniasis from Saudi Arabia of dogs confirmed to have cutaneous leishmaniasis. Further epidemiological and molecular investigations of domestic and wild canine infections with L. major, L. tropica and L. infantum in endemic and nonendemic areas of Saudi Arabia are required, for leishmaniasis control.

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Protozoa, helminths and ectoparasites are the major groups of parasites distributed worldwide. Currently, these parasites are treated with chemotherapeutic antiprotozoal drugs, anti-helminthic and anti-ectoparasitic agents, but, with the passage of time, resistance to these drugs has developed due to overuse. In this scenario, nanoparticles are proving to be a major breakthrough in the treatment and control of parasitic diseases. In the last decade, there has been enormous development in the field of nanomedicine for parasitic control. Gold and silver nanoparticles have shown promising results in the treatments of various types of parasitic infections. These nanoparticles are synthesized through the use of various conventional and molecular technologies and have shown great efficacy. They work in different ways, that include damaging the parasite membrane, DNA (Deoxyribonucleic acid) disruption, protein synthesis inhibition and free-radical formation. These agents are effective against intracellular parasites as well. Other nanoparticles, such as iron, nickel, zinc and platinum, have also shown good results in the treatment and control of parasitic infections. It is hoped that this research subject will become the future of modern drug development. This review summarizes the methods that are used to synthesize nanoparticles and their possible mechanisms of action against parasites.