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Objective: To determine the involvement and the modulatory effects of IL-33 during Plasmodium berghei ANKA (PbA) infection. Methods: PbA infection in male ICR mice was utilized as a model of malaria. Systemically circulating IL-33 levels were determined in blood plasma by enzyme-linked immunosorbent assay (ELISA). After 24 hours post-inoculation of PbA, recombinant IL-33 and ST2, and antibodies against IL-33 and IgG treatments were administered daily for 3 days. Tissue expression and localization of IL-33 were assessed in organs generally affected by malaria via immunohistochemistry. Moreover, histopathological examination was performed to assess the effects of the treatments. Results: The levels of systemic IL-33 were elevated at the critical phase of PbA infection. Likewise, immunohistochemical analysis revealed a significant upregulation of IL-33 expression at the critical phase in the brain, lungs, and spleen of PbA-infected mice as compared to healthy controls. Treatment with IL-33 protected against experimental cerebral malaria development and reduced pathological features in the brain and lungs of the PbA-infected mice. Conclusions: A potential critical role and involvement of IL-33 in PbA infection may hint at the resolution of immunopathological sequelae associated with malaria.

Identification of drug target in protozoan T. gondii is an important step in the development of chemotherapeutic agents. Likewise, exploring phytochemical compounds effective against the parasite can lead to the development of new drug agent that can be useful for prophylaxis and treatment of toxoplasmosis. In this review, we searched for the relevant literature on the herbs that were tested against T. gondii either in vitro or in vivo, as well as different phytochemicals and their potential activities on T. gondii. Potential activities of major phytochemicals, such as alkaloid, flavonoid, terpenoids and tannins on various target sites on T. gondii as well as other related parasites was discussed. It is believed that the phytochemicals from natural sources are potential drug candidates for the treatment of toxoplasmosis with little or no toxicity to humans.

Infection with Toxoplasma gondii remains widespread because water and food serve as major sources of sporulated oocysts. Infection is poorly controlled as current medications have limited efficacious and severe side effects, and are accompanied by potential development of resistance, and there is an absence of vaccine. The effects of ethanolic extract of Andrographis paniculata (EEAP) on T. gondii in vitro were evaluated. EEAP, obtained through maceration of leaf powder with 100% ethanol for three days, contained an alkaloid, phytosterols and phytophenolic compounds. IC50 (50% inhibitory concentration) of EEAP against Vero cells was 142 µg/ml and against T. gondii RH strain growth in Vero cells was 4.4 µg/ml (selectivity index = 35) compared to 8.3 µg/ml for clindamycin. EEAP (4.4 µg/ml) inhibited tachyzoite cell invasion and intracellular proliferation >70 and 80% respectively compared to control following a 48-hour treatment. These findings showed that EEAP contains promising drug candidates effective against T. gondii and was safe to host cells.

The major route for Toxoplasma gondii (T. gondii) infection is through the ingestion of foods contaminated with oocyst from cat faeces. The microscopic detection of T. gondii oocysts in cat faeces is challenging, which contributes to the failure of detecting or differentiating it from other related coccidian parasites. This study aims to detect T. gondii oocysts in cat faeces using two multicopy-target PCR assays and to evaluate their genetic diversity. Cat faecal (200) samples were collected from pet cats (PCs; 100) and free-roaming cats (FRCs; 100) within Klang Valley, Malaysia, and screened for coccidian oocysts by microscopy using Sheather’s sucrose floatation. PCR assays were performed on each faecal sample, targeting a B1 gene and a repetitive element (REP) gene to confirm T. gondii oocysts. Additionally, the PCR amplicons from the REP gene were sequenced to further confirm T. gondii-positive samples for phylogenetic analysis. Microscopy detected 7/200 (3.5%) T. gondii-like oocysts, while both the B1 gene and the REP gene detected 17/200 (8.5%) samples positive for T. gondii. All samples that were microscopically positive for T. gondii-like oocysts were also shown to be positive by both B1 and REP genes. The BLAST results sequenced for 16/200 (8.0%) PCR-positive T. gondii samples revealed homology and genetic heterogeneity with T. gondii strains in the GenBank, except for only one positive sample that did not show a result. There was almost perfect agreement (k = 0.145) between the two PCR assays targeting the B1 gene and the REP gene. This is the first report on microscopic, molecular detection and genetic diversity of T. gondii from cat faecal samples in Malaysia. In addition, the sensitivities of either the B1 gene or REP gene multicopy-target PCR assays are suitable for the accurate detection of T. gondii from cat faeces.

Dengue fever (DF) is a global health problem and considered to be endemic in Malaysia. Conventional mosquito traps currently applied as vector control do not effectively reduce Aedes mosquito population. AedesTech Mosquito Home System (AMHS) is an autocidal ovitraps for Aedes mosquitoes that uses the ‘lure and kill’ concept and is expected to be able to reduce Aedes mosquito population. The effectiveness of AMHS in reducing Aedes mosquito population was investigated in Block A, B and D (control) of the 17th College, Universiti Putra Malaysia (UPM). For the first two weeks (pre-intervention), the conventional ovitraps were used to obtain the initial abundance of mosquito population in Block A, B and D. Subsequently, AMHS was used for the next three months and again followed by the conventional ovitrap for the final two weeks (post-intervention). Ovitrap Index, Hatching Index and percentage of emergence of adult mosquitoes were calculated once every two weeks. Data were analysed using Paired Sample T-test. Values were considered significant at p≤0.05. The Ovitrap Index that indicates the mosquito population at Block A and B was significantly higher (p≤0.05) than of Block D. Hatching Index of AMHS was significantly lower (p≤0.05) then conventional ovitraps. All mosquito eggs collected in AMHS did not develop into adult mosquitoes. There was a significant reduction (p≤0.05) in the mosquito population between the pre- and post-intervention. In conclusion, AMHS was effective in reducing the mosquito population in 17th College, UPM. Therefore, it is believed to be a very promising vector management option to control the incidence of DF.

Background and Aim: Highly sensitive and specific diagnostic assay for the detection of Strongyloides is needed due to the intermittent and low concentration of eggs, larvae and adult worms that can be found in a faecal specimen. In some cases, repeated sampling of the faecal specimen is required to obtain satisfactory and reliable results. The aim of the study is to develop and evaluates monoclonal antibody-based Sandwich ELISA for the detection of coproantigen associated with Strongyloides infection using S. ratti as a model. Place and Duration of Study: Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, University Malaysia, Between September 2018 and March 2019. Methodology: The monoclonal antibody was raised against a soluble antigen of the infective filariform larvae (iL3) of S. ratti. The monoclonal antibody produced (IgG2bMAb) was evaluated for cross-reactivity against homologous and heterologous helminth antigens such as excretory-secretory (ES), infective larvae (iL3) and coproantigen of S. ratti, adult worms of A. caninum, A. suum, T. canis and T. cati. Results: An IgG2bMAb was observed to react with 30 kDa proteins associated with all homologous antigen from iL3, ES and coproantigen of S. ratti and cross-reacted with one heterologous antigen from adult worm of A. caninum at the same molecular weight. There was no cross-reaction observed with other heterologous antigens from adult worms of T. canis, T. cati and A. suum. The sensitivity of IgG2bMAb for the detection of S. ratti was 85% in Sandwich ELISA. Cross- reaction was observed with hookworm antigen that caused by A. caninum in Western immunoblotting. Conclusion: The results indicated that IgG2b have an immunodiagnostic property as IgG2bMAb and was able to detect antigens from coproantigen related to S. ratti with 85% sensitivity based on Sandwich ELISA) even though cross-reaction was observed with A. caninum. These findings will be very useful to tackle many

Infection with Strongyloides stercoralis is associated with asymptomatic chronic disease involving the gut and respiratory systems and can persist for long period undetected leading to development of fatal hyperinfection syndrome. The severity is even more in immunocompromised individuals or patients undergoing immune suppressive therapy. Unfortunately the disease is difficult to diagnose due to low parasite load and the irregular larval output. Development of efficient diagnostic techniques requires large supply of infective larvae and this can be achieved through in vivo maintenance of the parasite. In this regard, S. ratti is being used as a model instead of S. stercoralis due to difficulty and risk of infection. In this study, a significant amount of previously characterized filariform (iL3) larvae of S. ratti was collected. Chronic infection was successfully established and maintained by experimentally induced immunosuppression of Wistar rats following oral administration of prednisolone. This model can serve as a good source of infective larvae for production of monoclonal antibodies and development of diagnostic assays for prevention of the disease. It can also provide room for further research in diagnostics of human strongyloidiasis.

Salmonellosis is reported as one of the main cause of diarrhoeal diseases globally. The disease is also associated with enteric fever, including typhoid which is a potentially fatal systemic illness bedeviling many developing countries. The disease is estimated to affect nearly 17 million people with over 150,000 deaths occurring annually. Salmonellosis is also beginning to emerge as a foodborne infection characterized by significant economic and public health hazard with global ramifications. High prevalence of the disease is directly related to poor sanitation and hygiene, consumption and use of unsafe water, overcrowding and social unrest. A significant number of Iraqis are affected annually with a death rate of 10-20 %, mainly resulting from limited access to fresh water and improper sewage disposal into the river bodies. This review provides an overview of Salmonella infection in human and animals, with emphasis on the economic and public health burden of the disease in Iraq.

The status of toxoplasmosis management is challenged by drug intolerance, compromised efficacy and potential development of drug resistance. However, currently, there are very limited targets on T. gondii that serve as the site of action of current medications. This review aimed to explore more potential targets that are essential to parasite survival and are absent in humans. Many unexplored targets on T. gondii exist and their specificities to the parasite make them ideal drug targets. The present review had searched relevant English databases such as PubMed, Scopus, Google scholar and Science Direct, for relevant literature on the therapeutic target of T. gondii. Many of the enzyme systems in several pathways are essentially palatable as drug targets. Establishing compounds that can target these enzymes on T. gondii will greatly be beneficial in treating acute and chronic toxoplasmosis in humans.

Background: Currently, most of the available serological diagnostic kits for strongyloidiasis are based on the use of the crude antigens of Strongyloides ratti, which are good, but with less sensitivity towards the infection. Hence, this study aimed to produce and evaluate monoclonal antibody for detecting soluble parasite antigen in animal sera. Methods: The study was conducted in the Department of Medical Microbiology and Parasitology, University Putra Malaysia in 2014-2017. Saline extract protein from the infective larvae of S. ratti was used to immunize BALB/c mice and subsequent fusion of the B-cells with myeloma cells (SP2/0) using 50% PEG. The hybridomas were cultured in HAT medium and cloned by limiting dilutions. Positive hybrids were screened by indirect ELISA. The ascites fluid from the antibody-secreting hybridoma was purified and the MAb was characterized by western-blots and evaluated in sandwich ELISA for reactivity against the homologous and heterologous antigens. Results: An IgG1 that recognizes a 30 and 34 kDa protein bands was obtained. The MAb was recognized by all S. ratti-related antigens and cross-reacted with only Toxocara canis antigens in both assays. The minimum antigen detection limit was found to be 5 ng/ml. All antibody-positive rat and dog sera evaluated have shown antigen-positive reactions in Sandwich-ELISA. Conclusion: The MAb produced, was able to detect antigens in strongyloidiasis and toxocariasis in animal models and may also be useful for the serological detection of active strongyloidiasis and visceral toxocariasis in human sera.

The recently identified cytokines—interleukin (IL)-35 and interleukin (IL)-37—have been described for their anti-inflammatory and immune-modulating actions in numerous inflammatory diseases, auto-immune disorders, malignancies, infectious diseases and sepsis. Either cytokine has been reported to be reduced and in some cases elevated and consequently contributed towards disease pathogenesis. In view of the recent advances in utilizing cytokine profiles for the development of biological macromolecules, beneficial in the management of certain intractable immune-mediated disorders, these recently characterized cytokines (IL-35 and IL-37) offer potential as reasonable targets for the discovery of novel immune-modulating anti-inflammatory therapies. A detailed comprehension of their sophisticated regulatory mechanisms and patterns of expression may provide unique opportunities for clinical application as highly selective and target specific therapeutic agents. This review seeks to summarize the recent advancements in discerning the dynamics, mechanisms, immunoregulatory and anti-inflammatory actions of IL-35 and IL-37 as they relate to disease pathogenesis.

The increasing demand for monoclonal antibodies (mAbs) used for diagnostic and therapeutic applications has led to the development of large scale manufacturing processes, with improvements in production achieved through continuous optimization of the inherent systems. The number of monoclonal antibodies (mAbs) that have already been approved for therapeutic applications and for use in clinical trials have significantly increased in the past few years. In view of the side effects and limitations of mAbs, several improvements and modifications to monoclonal antibodies have been developed. These modifications have facilitated the use of mAbs in various forms of therapeutic applications such as treatment of infectious diseases caused by bacterial, viral, fungal and parasitic organisms. Monoclonal antibodies have also been applied in the treatment of non-infectious diseases such as cancer, immune diseases, arthritis and other disorders resulting from organ transplantation. This review highlights mAbs applications in biomedicine, and discusses state-of-the-art technologies related to their potential uses.

Human strongyloidiasis research requires a large supply of Strongyloides stercoralis.This can be achieved through in vivo maintenance of Strongyloides stercoralis in Merionesunguiculatus, but isolating a large quantity of Strongyloides stercoralis to establish thecolony from an infected patient is too difficult to achieve. Hence, Strongyloides ratti havebeen used as a model in human strongyloidiasis research. This study describes a successfulestablishment and maintenance of Strongyloides ratti infection in experimentallyimmunosuppressed Wistar rats. Large quantities of filariform (iL3) larvae of Strongyloidesratti for research related to human strongyloidiasis have been harvested following thisprotocol. Molecular detection method based on PCR using species specific primers was usedto confirm the species of the harvested infective larvae (iL3). Additionally, the identificationof histopathological lesions confirmed the presence of infective larvae (iL3) in the liver andlungs as a result of an increased parasite burden due to hyperinfection and disseminateddisease. This pathological presentation was found to be similar to that reported inStrongyloides stercoralis-infected immunocompromised human subjects.

Background Emergence of chloroquine (CQ) resistance among different strains of Plasmodium falciparum is the worst incident that has ever faced the dedicated efforts to eradicate malaria. The main cause of CQ resistance is over-activity of the pumping mechanism that ousts CQ outside the DV. This urged the scientists to look for other alternatives or adjuvants that augment its action. CQ The study aimed to test the potential of five coumarin derivatives, namely; umbeliferon, esculetin, scopoletine, herniarin and 3-aminocoumarine to inhibit plasmodium growth and reverse CQ resistance in Plasmodium falciparum K1 and 3D7. They are highly ubiquitous in nature and are famous by their diverse pharmacological effects. SYBRE green-1 based drug sensitivity assay was used to screen the effect of CQ and each coumarin on the parasite growth and isobologram technique was to assess the interaction of the coumarins with CQ. Effect of each coumarin on both RBCs and Vero cells stability as well as on RBCs fragility were screened to exclude any toxic impact on normal cells. On the other hand, their effect on hemozoin formation was screened to investigate about their molecular mechanism. For molecular characterization, Their antioxidant properties were determined using the conventional in vitro tests and their characters were obtained from Molinspiration Simulation Software. Results showed that all of them were safe to human cells, have weak to moderate plasmodial growth inhibitory effect and only umbeliferon, 3- aminocoumarin and esculetin has interacted effectively with CQ. These actions are neither correlated with hemozoin formation inhibition nor to the antioxidant mechanisms. Further studies recommended to investigate the mechanism of their action. Overall, all the tested coumarins are not ideal to be used in the conventional malaria therapy and only umbeliferon, 3-aminocoumarin and esculetin can be suggested to potentiate CQ action.

Objective: To explore whether its antiplasmodium effect of andrographolide is attributed to its plausible effect on the plasma membrane of both Plasmodium falciparum infected and non-infected RBCs. Methods: Anti-plasmodium effect of andrographolide against Plasmodium falciparum strains was screened using the conventional malaria drug sensitivity assay. The drug was incubated with uninfected RBCs to monitor its effect on their morphology, integrity and osmotic fragility. It was incubated with the plasmodium infected RBCs to monitor its effect on the parasite induced permeation pathways. Its effect on the potential of merozoites to invade new RBCs was tested using merozoite invasion assay. Results: It showed that at andrographolide was innocuous to RBCs at concentrations approach its therapeutic level against plasmodia. Nevertheless, this inertness was dwindled at higher concentrations. Conclusions: In spite of its success to inhibit plasmodium induced permeation pathway and the potential of merozoites to invade new RBCs, its anti-plasmodium effect can't be attributed to these functions as they were attained at concentrations higher than what is required to eradicate the parasite. Consequently, other mechanisms may be associated with its claimed actions.

Purpose: To detect Strongyloides ratti in faecal samples using conventional methods and to confirm the identification using a sensitive and specific method, namely, polymerase chain reaction (PCR). Methods: A PCR method targeting the small subunit of the rRNA gene was performed in this study for the detection of DNA from Strongyloides ratti (an animal model of S. stercoralis) in faecal samples of wild Brown rats, Rattus norvegicus. Results: Strongyloides ratti was detected in 34.2 % of collected rats by different conventional techniques and confirmed by PCR. The essay presented 100 % sensitivity with Strongyloides universal primer. Conclusion: The findings of this study suggest that the application of PCR with universal primer is a very sensitive methodology to detect S. ratti in faecal material of wild rats infected even with very low parasite burden.

Emergence of drugs resistant strains of Plasmodium falciparum has augmented the scourge of malaria in endemic areas. Antimalaria drugs act on different intracellular targets. The majority of them interfere with digestive vacuoles (DVs) while others affect other organelles, namely, apicoplast and mitochondria. Prevention of drug accumulation or access into the target site is one of the mechanisms that plasmodium adopts to develop resistance. Plasmodia are endowed with series of transporters that shuffle drugs away from the target site, namely, pfmdr (Plasmodium falciparum multidrug resistance transporter) and pfcrt (Plasmodium falciparum chloroquine resistance transporter) which exist in DV membrane and are considered as putative markers of CQ resistance. They are homologues to human P-glycoproteins (P-gh or multidrug resistance system) and members of drug metabolite transporter (DMT) family, respectively. The former mediates drifting of xenobiotics towards the DV while the latter chucks them outside. Resistance to drugs whose target site of action is intravacuolar develops when the transporters expel them outside the DVs and vice versa for those whose target is extravacuolar. In this review, we are going to summarize the possible pfcrt and pfmdr mutation and their role in changing plasmodium sensitivity to different anti-Plasmodium drugs.

Toward the control and possible eradication of lymphatic filaraisis a new paradigm is into the development of antifilarial nucleic acid vaccine i.e to genetically engineered vaccines that can block zoonotic transmission of brugian filariasis. This vaccine may form the basis of a possible elimination of microfilariae in animal reservoirs that break zoonotic transmission from animals to humans.

Objective: Intestinal microsporidia is an emerging human disease caused by microsporidia. A study was conducted to determine the prevalence of microsporidia in patients with gastro-intestinal symptoms and to examine the clinical manifestations associated with intestinal microsporidiosis. Methods: A descriptive cross-sectional study using a well-structured questionnaire; a review of medical records was also undertaken. Positive stool samples were defined as presence of one or more pinkish-violet ovoid structures with a belt-like stripe under high power field (100x) using modified gram-chromotrope stain (MGC). Results: A total of 353 faecal specimens of patients was examined and 100 patients were found to have positive stool samples for microsporidia. The overall prevalence of microsporidia was 28.3%. Acute and chronic diarrhoea were seen in 49.0% and 36.0% patients, respectively. The commonest clinical presentations were diarrhoea (85.0%) with 83.0 % of patients having loose or watery stools, vomiting (75.0%), foul-smelling stools (60.0%), nausea (59.0%) and cramping abdominal pain (39.0%). The least common symptoms were fever (15.0%), mucous in stool (5.0%) and blood in stool (4.0%). Conclusion: This study concludes that the prevalence of microsporidia is still high (28.3%) and the majority of patients (93.0%) are symptomatic; the most common gastro-intestinal symptom is diarrhoea with loose or watery stools. Hence, it is recommended that a stool screening for microsporidia be done in selected patients presented with gastrointestinal symptoms.

The objectives of this study were to clone gene that encode filarial SXPI protein followed by in vitm expression of the protein. The Special Programme for Research and Training in Tropical Diseases (TDR) WHO has advocated SXPl as one of the vaccine candidate to curb filarial infection. SXPl antigen has been reported to confer protective immunity, causing reduction of microfilaraemia levels in jirds (Meriones unguiculatus) blocking subsequent Brugia malayi infection. In this study, the gene that encode SXPl antigen was 517 bp in length and was extracted and amplified from the infective stage (L3) of subperiodic Brugia malayi. The gene was successfully cloned into replication vector p ~ ~ ~ 2(Inv. it1rog en) followed by subcloning into mammalian expression vector pVAXl (Invitrogen). The presence of SXPl gene in - both vectors were validated by polymerase chain reaction (PCR), restriction enzymes analysis (RE) and finally by automated sequencing. The cloned SXPl in pVAX was designated as pVAXISXP1. The plasmid bearing SXPI gene was transfected into two types of animal cell lines (COS-7 and CHO) using Polyfect Transfection Reagent (Qiagen). The successful expression of targeted gene in the mammalian cell lines were determined by RT-PCR and Western Blotting. The PCR product of the transfected cells was 517 bp on the agarose gel. In addition, the -20 kDa of expressed SXPl protein was detected on nitrocellulose membrane by rabbit polyclonal antibody against the SXPI protein. This study has successfully established the ground work for future deliberations towards the development of antibrugia transmission blocking genetic vaccine.