Salivary Extracts Research Articles

Exploring salivary lipid profile changes in COVID-19 patients: Insights from mass spectrometry analysis

The most common COVID-19 testing relies on the use of nasopharyngeal swabs. However, this sampling step is very uncomfortable and is one of the biggest challenges regarding population testing. In the present study, the use of saliva as an alternative sample for COVID-19 diagnosis was investigated. Therefore, high-resolution mass spectrometry analysis and chemometric approaches were applied to salivary lipid extracts. Two data organizations were used: classical MS data and pseudo-MS image datasets. The latter transformed MS data into pseudo-images, simplifying data interpretation. Classification models achieved high accuracy, with pseudo-MS image data performing exceptionally well. PLS-DA with OPSDA successfully separated COVID-19 and healthy groups, serving as a potential diagnostic tool. The most important lipids for COVID-19 classification were elucidated and include sphingolipids, ceramides, phospholipids, and glycerolipids. These lipids play a crucial role in viral replication and the inflammatory response. While pseudo-MS image data excelled in classification, it lacked the ability to annotate important variables, which was performed using classical MS data. These findings have the potential to improve clinical diagnosis using rapid, non-invasive testing methods and accurate high-volume results.

Identification, Baculoviral Expression, and Biochemical Characterization of a Novel Cholinesterase of Amblyomma americanum (Acari: Ixodidae).

A cDNA encoding a novel cholinesterase (ChE, EC 3.1.1.8) from the larvae of Amblyomma americanum (Linnaeus) was identified, sequenced, and expressed in Sf21 insect cell culture using the baculoviral expression vector pBlueBac4.5/V5-His. The open reading frame (1746 nucleotides) of the cDNA encoded 581 amino acids beginning with the initiation codon. Identical cDNA sequences were amplified from the total RNA of adult tick synganglion and salivary gland, strongly suggesting expression in both tick synganglion and saliva. The recombinant enzyme (rAaChE1) was highly sensitive to eserine and BW284c51, relatively insensitive to tetraisopropyl pyrophosphoramide (iso-OMPA) and ethopropazine, and hydrolyzed butyrylthiocholine (BuTCh) 5.7 times as fast as acetylthiocholine (ATCh) at 120 µM, with calculated KM values for acetylthiocholine (ATCh) and butyrylthiocholine of 6.39 µM and 14.18 µM, respectively. The recombinant enzyme was highly sensitive to inhibition by malaoxon, paraoxon, and coroxon in either substrate. Western blots using polyclonal rabbit antibody produced by immunization with a peptide specific for rAaChE1 exhibited reactivity in salivary and synganglial extract blots, indicating the presence of AaChE1 antigenic protein. Total cholinesterase activities of synganglial or salivary gland extracts from adult ticks exhibited biochemical properties very different from the expressed rAaACh1 enzyme, evidencing the substantial presence of additional cholinesterase activities in tick synganglion and saliva. The biological function of AaChE1 remains to be elucidated, but its presence in tick saliva is suggestive of functions in hydrolysis of cholinergic substrates present in the large blood mean and potential involvement in the modulation of host immune responses to tick feeding and introduced pathogens.

In vivo Antioxidant Related Effect of Orally Administered Aqueous Extract of Saliva triloba in Human Volunteers

Saliva triloba, belongs to the Lamiaceae family, is one in all the vital medicinal plant species. This work aims to study the antioxidant-related effects of trilobite saliva in the human body through in vivo studies and the effects on liver, kidney, and heart function tests. For five days, nine healthy participants consumed 250 mL of trilobite saliva extract orally. On the fifth day, blood samples were taken one hour before and after the first dosage of water extract (samples I and II, respectively), and again one day after the last dose (ie, day 6, sample III). Before the first dosage, the first blood sample was taken (ie sample I) was used as a control for the subsequent II and III samples. Subsequent determinations were performed: serum total antioxidant status (TAS), red blood cell reduced glutathione (GSH), red blood cell superoxide dismutation (SOD) A activity, malondialdehyde (MDA), and serum-selected biochemical tests. After 5 days of oral administration of trilobite saliva extract in healthy volunteers, serum TAS, erythrocyte GSH and erythrocyte SOD activity were significantly increased, and had no influence on serum biochemical examinations of kidney, liver, heart, pancreas, etc., contrasted with zero-time management. In Conclusion, salivary clover extract has effective anti-oxidation related effects in vivo. Because these findings were obtained in healthy people without oxidative stress, it means that clover saliva will enhance the bottom line of the defense system against probable oxidative stress while having no adverse effects, decreasing or avoiding pathological diseases associated with oxidative stress

An Integrative Sialomic Analysis Reveals Molecules From Triatoma sordida (Hemiptera: Reduviidae).

Triatomines have evolved salivary glands that produce versatile molecules with various biological functions, including those leading their interactions with vertebrate hosts’ hemostatic and immunological systems. Here, using high-throughput transcriptomics and proteomics, we report the first sialome study on the synanthropic triatomine Triatoma sordida. As a result, 57,645,372 reads were assembled into 26,670 coding sequences (CDS). From these, a total of 16,683 were successfully annotated. The sialotranscriptomic profile shows Lipocalin as the most abundant protein family within putative secreted transcripts. Trialysins and Kazal-type protease inhibitors have high transcript levels followed by ubiquitous protein families and enzyme classes. Interestingly, abundant trialysin and Kazal-type members are highlighted in this triatomine sialotranscriptome. Furthermore, we identified 132 proteins in T. sordida salivary gland soluble extract through LC-MS/MS spectrometry. Lipocalins, Hemiptera specific families, CRISP/Antigen-5 and Kazal-type protein inhibitors proteins were identified. Our study provides a comprehensive description of the transcript and protein compositions of the salivary glands of T. sordida. It significantly enhances the information in the Triatominae sialome databanks reported so far, improving the understanding of the vector’s biology, the hematophagous behaviour, and the Triatominae subfamily’s evolution.

Ascendancy of betle leaf in the metabolism on trophoblasts

Introduction and Aim: Pregnancyis a physiological state to sustain the developing fetus accompanied with high-energy demand and an increased oxygen requirement, associated with diverse metabolic and vascular changes in the maternal system. Oxygen is crucial for the proper proliferation and differentiation of trophoblast, the principal cells of the transient organ placenta. Placental hypoxia/ischemia results in the dysregulation in the physiological and metabolic activities of trophoblast. Readily available, cost-effective pharmacological herbal preparation betle leafmay be helpful in the development of novel therapeutic interventions to manage the maternal complication like hypertension and fetal growth restrictions resulting in low-birth-weight babies. This has raised the concern to ascertain the ascendancy of salivary and diastase extracts of betle leafon theexpression of leptin, adiponectin and CYP19A1 inplacental trophoblast metabolism. Methodology: Subjecting the placental trophoblast to in vitro hypoxia may highlight the crucial role of oxygen and impact of betle leaf extracts in altering the various metabolic markers. Results: Both the extracts modulate the levels of leptin, adiponectin and CYP19A1in regulating energy metabolism and oxidation process. Conclusion: This study also suggests that differential expression leptin, adiponectin and CYP19A1, influences this energy imbalance in response to the stress stimuli such as the hypoxiaand its relationship with feto-placental metabolism and fetal growth. The ascendancy of betle leaf extracts on the metabolism of trophoblasts requires sufficient oxygen is inferred from the in vitro hypoxic study.

Enzymatic characterization of the saliva of the eriophyid mite, Aceria pongamiae Keifer1966 (Acari: Eriophyidae) and the bacterial endobiome of the galls induced on Pongamia pinnata (L.) Pierre (Fabaceae).

Galls, like other regular plant organs, possess their own histological and physiological features. A high degree of specificity is maintained between the host and the inducer, and hence gall morphogenesis is highly conserved and would help trace gall lineages and cell fate. The present study highlights the induction and subsequent development of leaf galls on the Indian Beech tree, Pongamia pinnata (L) Pierre (Fabaceae), mediated through the active participation of a gall-inducing species of eriophyid mite, Aceria pongamiae Keifer and gall-associated bacterial endobiome. The saliva of A. pongamiae and selected strains of gall-associated bacterial endobiome were characterized in part during the study. Three strains of Staphylococcus arlettae (PGP1-3) and one strain of Bacillus flexus (PGP4) were identified from the leaf galls through 16S rDNA sequencing. The mite saliva displayed tryptophanase activity, and the bacterial strains showed differential enzyme activities (protease, amylase, cellulase, DNAse, pectinase, tryptophanase, and catalase). All four strains of bacterial endobiome exhibited unique metal tolerance as well as pH and temperature regulating activity. Evaluation of the potential role of the mite saliva and the gall associated bacterial endobiome in gallogenesis was done by monitoring the plant growth-promoting activity of the salivary extract and the isolated bacterial strains through in vitro seed (Vigna radiata) germination assay. Salivary extract of the mite showed the highest rate of plant growth-promoting activity compared with that of the isolated strains of bacterial endobiome. The present study forms the first attempt that illustrates the characteristic features of the saliva of the gall inducer and the gall associated bacterial endobiome. Based on the results of the current study, we suggest that eriophyid mite saliva and the gall-associated microbes play significant roles in the induction of cecidia.

Assessment of anti-cancer potential of Hyalomma dromedarii salivary glands extract: in vitro study

Cancer is still one of the deadly diseases worldwide and the need for naturally-derived effectors is a pursued aim in health research. With the outstanding ability to bypass the host’s various defense mechanisms, tick saliva constitutes an interesting rich source for the discovery of therapeutically-valuable molecules. Therefore, the present work aimed to evaluate the anti-tumor potential of Hyalomma dromedarii salivary glands extract (SGE). Three cell lines were used in this study, namely HCT116 (colorectal cancer), A549 (lung cancer) and HFB4 (normal skin) cells. MTT assay and light microscopy revealed significant dose-dependent inhibition of proliferation with obvious morphological changes in tested cell lines. Colon cells exhibited more sensitivity than lung ones, therefore they were selected for further investigations. Although cytotoxic effects were observed in treated-HFB4 cells, its IC50 value was much higher than that of HCT116 cells. Flow cytometry analysis of treated HCT116 cells showed accumulation of cellular DNA at the G2/M phase and induction of apoptosis. In addition, RT-qPCR indicated down-regulation in the expression of vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), transforming growth factor-β (TGF-β) and interleukin-4 (IL-4) genes. These results demonstrated that H. dromedarii SGE has anti-proliferative, apoptotic and anti-angiogenic potential. Also, they open perspectives for characterization of effective molecules that could be used in developing treatments for colorectal cancer. Further investigations are required to identify the mechanisms, molecules and signaling pathways involved in the inhibitory effect of the SGE.

IgG Antibody Responses to the Aedes albopictus 34k2 Salivary Protein as Novel Candidate Marker of Human Exposure to the Tiger Mosquito.

Mosquitoes of the Aedes genus transmit arboviruses of great importance to human health as dengue, chikungunya, Zika and yellow fever. The tiger mosquito Aedes albopictus can play an important role as arboviral vector, especially when Aedes aegypti is absent or present at low levels. Remarkably, the rapid worldwide spreading of the tiger mosquito is expanding the risk of arboviral transmission also to temperate areas, and the autochthonous cases of chikungunya, dengue and Zika in Europe emphasize the need for improved monitoring and control. Proteomic and transcriptomic studies on blood feeding arthropod salivary proteins paved the way toward the exploitation of genus-specific mosquito salivary proteins for the development of novel tools to evaluate human exposure to mosquito bites. We previously found that the culicine-specific 34k2 salivary protein from Ae. albopictus (al34k2) evokes specific IgG responses in experimentally exposed mice, and provided preliminary evidence of its immunogenicity to humans. In this study we measured IgG responses to al34k2 and to Ae. albopictus salivary gland protein extracts (SGE) in individuals naturally exposed to the tiger mosquito. Sera were collected in two areas of Northeast Italy (Padova and Belluno) during two different time periods: at the end of the low- and shortly after the high-density mosquito seasons. Anti-SGE and anti-al34k2 IgG levels increased after the summer period of exposure to mosquito bites and were higher in Padova as compared to Belluno. An age-dependent decrease of anti-saliva IgG responses was found especially in Padova, an area with at least 25 years history of Ae. albopictus colonization. Moreover, a weak correlation between anti-saliva IgG levels and individual perception of mosquito bites by study participants was found. Finally, determination of anti-al34k2 IgG1 and IgG4 levels indicated a large predominance of IgG1 antibodies. Overall, this study provides a convincing indication that antibody responses to al34k2 may be regarded as a reliable candidate marker to detect temporal and/or spatial variation of human exposure to Ae. albopictus; a serological tool of this kind may prove useful both for epidemiological studies and to estimate the effectiveness of anti-vectorial measures.

Co-administration of Erythromycin and Leech Salivary Extract Alleviates Osteomyelitis in Rats Induced by Methicillin-Resistant Staphylococcus aureus.

Erythromycin (Ery) and leech saliva (LS) can inhibit Staphylococcus aureus growth in in vitro conditions. This study aimed to evaluate the activities and synergy between Ery and LS on chronic osteomyelitis in male Wistar rat's tibia induced by methicillin-resistant S. aureus (MRSA). Four weeks after osteomyelitis induction, rats were divided into four groups including no treatment (control), Ery monotherapy (orally), LS monotherapy, or Ery + LS twice daily for 2 weeks. Staphylococcus aureus growth, pathological signs and inflammatory cytokine tumour necrosis factor-alpha (TNF-α) levels were assessed. Rats tolerated all therapeutic strategies well during the experiment. The Ery treatment alone significantly decreased bacterial growth, pathological signs and TNF-α levels. Leech saliva alone reduced TNF-α level significantly, but did not produce a significant reduction in bacterial growth and pathological signs. Ery + LS treatment significantly decreased bacterial growth, considerably alleviated bone pathological signs and decreased TNF-α levels compared with other groups. Statistical analysis suggested that there was a stronger efficiency and synergistic action of Ery and LS when combined against MRSA-induced osteomyelitis in rats. The present study suggests that LS may have clinical utility to treat MRSA-induced osteomyelitis when combined with Ery or other therapeutics.

Salivary proteins of Phloeomyzus passerinii, a plant-manipulating aphid, and their impact on early gene responses of susceptible and resistant poplar genotypes

Successful plant colonization by parasites requires the circumvention of host defenses, and sometimes a reprogramming of host metabolism, mediated by effector molecules delivered into the host. Using transcriptomic and enzymatic approaches, we characterized salivary glands and saliva of Phloeomyzus passerinii, an aphid exhibiting an atypical feeding strategy. Plant responses to salivary extracts of P. passerinii and Myzus persicae were assessed with poplar protoplasts of a susceptible and a resistant genotype, and in a heterologous Arabidopsis system. We predict that P. passerinii secretes a highly peculiar saliva containing effectors potentially interfering with host defenses, biotic stress signaling and plant metabolism, notably phosphatidylinositol phosphate kinases which seemed specific to P. passerinii. Gene expression profiles indicated that salivary extracts of M. persicae markedly affected host defenses and biotic stress signaling, while salivary extracts of P. passerinii induced only weak responses. The effector-triggered susceptibility was characterized by downregulations of genes involved in cytokinin signaling and auxin homeostasis. This suggests that P. passerinii induces an intracellular accumulation of auxin in susceptible host genotypes, which is supported by histochemical assays in Arabidopsis. This might in turn affect biotic stress signaling and contribute to host tissue manipulation by the aphid.

Comparative analysis of total salivary lipopolysaccharide chemical and biological properties with periodontal status

ObjectiveClinical manifestations of Gram-negative bacteria mediated diseases can be influenced by how the host senses their major microbe-associated molecular pattern, the cell wall lipopolysaccharide (LPS). Keystone periodontal pathogens can produce a heterogeneous population of LPS molecules, with strikingly different host-microbiome interactions and immune outcomes. DesignStructure-function correlations of salivary LPS extracts in patients with periodontitis before and after periodontal treatment and healthy volunteers were analysed by comparing its lipid A and carbohydrate chain chemical structure and evaluating its endotoxin activity and inflammatory potential. ResultsSalivary LPS extracts from periodontitis patients were characterised by high m/z lipid A mass-spectrometry peaks, corresponding to over-acylated and phosphorylated lipid A ions and by a combination of rough and smooth LPS carbohydrate moieties. In contrast, gingival health was defined by the predominance of low m/z lipid A peaks, consistent with under-acylated and hypo-phosphorylated lipid A molecular signatures, with long and intermediate carbohydrate chains as determined by silver staining. Total, diseased salivary LPS extracts were stronger inducers of the recombinant factor C assay and triggered significantly higher levels of TNF-α, IL-8 and IP-10 production in THP-1 cells, compared to almost immunosilent healthy samples. Interestingly, salivary LPS architecture, endotoxin activity, and inflammatory potential were well conserved after periodontal therapy and showed similarities to diseased samples. ConclusionsThis study sheds new light on molecular pathogenic mechanisms of oral dysbiotic communities and indicates that the regulation of LPS chemical structure is an important mechanism that drives oral bacteria-host immune system interactions into either a symbiotic or pathogenic relationship.

Tissue Specific Extracellular Matrix Extract Promotes Salivary Gland Organoid Formation with Human Salivary Progenitors

Hypofunction of the salivary glands (SGs) has several detrimental effects. Several approaches can be used to restore the function of damaged SGs, such as tissue engineering based on stem cells and biomaterials. Among these, three dimensional (3D) culture without biomaterials (termed organoids) can recapitulate the characteristics of the native organ in vivo. However, despite the substantial progress made, most organoids which are formed from stem cells or cell aggregates still lack a specific tissue niche. We hypothesized that tissue specific ECM proteins are required for formation and maintenance of functional organoids. Thus, we evaluate the effect of human tissue specific ECM extracts on the formation of functional SG organoids containing human SG epithelial and mesenchymal cells. We prepared human salivary gland ECM (hSG-ECM) with a growth factor-enriched supplement and the prepared hSG-ECM was introdeced in a uniform high-throughput 3D platform. First, we determined the optimum culture conditions; organoids comprising 5,000 cells at a mesenchymal: epithelial cell ratio of 1:9 exhibited a low frequency of apoptosis, high proliferation capacity, and a structure resembling that of SGs. Introduction of hSG-ECM extract with proper concentration resulted in maintenance of the stem cell niche and promotion of stem cell differentiation. Moreover, treatment of the organoids with decellularized supplements increased their sensitivity to neurotransmitters. In conclusion, we developed functional human SG organoids using salivary progenitors and ECM extract. The SG organoids have potential for SG tissue repair, drug development, and disease modeling.

Efficacy of salivary and diastase extracts of Piper betle in modulating the cellular stress in placental trophoblast during preeclampsia

Background: Betle leaf (BL) is an ancient herb with a potential nontoxic natural antioxidant efficacy. Oral intake and chewing betel leaves have an effort on the moving parts of salivary gland and induce salivation and detoxification; hence plays a vital role in oral hygiene. BL produces and activates various salivary enzymes which include α-amylase, lipase, lysozyme, and lactoperoxidase. BL possess antibacterial, antioxidant, anti-diabetic, immunomodulatory, and antihypertensive properties. Hence, it can be effective in the treatment of hypertensive disorder of pregnancy like preeclampsia (PE). Objective: In this context, two extracts of BL (Salivary BL extract [SBLE] and diastase BL extract [DBLE]), proved to impart efficient radical scavenging activity in our previous research work were utilized to analyze their efficacy on the level of 4-hydroxy nonenal (4-HNE), heme oxygenase-1 (HO-1), asymmetric dimethylarginine (ADMA), adiponectin/leptin in the trophoblast isolated from placental tissue of both normotensive and preeclamptic patients. Materials and Methods: Trophoblasts were isolated from both subjects and incubated with different extracts of Piper betle (saliva and diastase) to assess the cellular stress in placental trophoblast during PE. Results: Results demonstrate that extracts of BL exhibit a significant role in regulating 4-HNE, ADMA, leptin, HO-1, and adiponectin in preeclamptic trophoblasts. Still, SBLE showed relatively higher efficiency in defining the level of 4-HNE, ADMA, leptin, HO-1, and adiponectin in preeclamptic trophoblasts than DBLE, suggesting that it may be attributed to the interaction of the phytochemicals present in BL with the components of saliva. Conclusion: Hence, BL may be recommended as the effective natural remedy in the management of pathological complications of PE; which may preclude low birthweight babies and ensure live fetal delivery. Abbreviations Used: 4-HNE: 4-hydroxy-nonenal, ADMA: Asymmetric dimethylarginine, BL: Betel leaf, BLE: Betel leaf extract, CO: Carbon monoxide, DB: Diastase with betel leaf, DBLE: Diastase betel leaf extract, ELISA: Enzyme-linked immunosorbent assay, eNOS: Endothelial nitric oxide synthase, FBS: Fetal bovine serum, GSH: Reduced glutathione, HBSS: Hank's balanced salt solution, HO-1: Heme oxygenase-1, iNOS: Inducible nitric oxide synthase, NO: Nitric oxide, NOS: Nitric oxide synthase, PE: Preeclampsia, ROS: Reactive oxygen species, SB: Saliva with betel leaf, SBLE: Salivary betel leaf extract.

A Comparative Study on the Effect of Tobacco Smoke and Tobbaco Salivary Extract on Serum Lipid Profile

A Comparative Study on the Effect of Tobacco Smoke and Tobbaco Salivary Extract on Serum Lipid Profile

Anti-Tubercular Activities and Molecular Characterization of Salivary Extract of Leech (<i>Hirudo medicinalis</i>) against <i>Mycobacterium tuberculosis</i>

Leech salivary extract (LSE) was screened for the anti-tubercular activity against Mycobacterium tuberculosis using microbroth dilution method. The bioactive components in LSE were determined using Shimadzu GC-MS QP2010 SE. The LSE exhibited bactericidal effects on M. tuberculosis at 50% (v/v). The result of the GC-MS analysis of LSE revealed seventeen (17) bioactive components. The major fatty acid components were oleic acid (33.9%) and palmitic acid also known as hexadecanoic acid (22.6%). Other bioactive components detected in appreciable amounts in LSE include, 4-bromobutyric acid (16.86%), 6,17-Octadiene-1-ol acetate (9.78%) and octahydro-1,4,9,9- tetramethyl (5.21%). The anti-tubercular activity of the LSE was attributed to these bioactive components. The results obtained suggest that leech salivary extract could be used in treating tuberculosis.

Effects of leech salivary extract (lse) on indices of liver function in rats

Effects of leech salivary extract (lse) on indices of liver function in rats

Thrombin inhibitor from the salivary gland of the camel tick Hyalomma dromedarii.

Blood-sucking arthropods have different types of anticoagulants to allow the ingestion of a blood meal from their hosts. In this study, five anticoagulants prolonging the activated partial thromboplastin time were resolved from the salivary gland crude extract of the camel tick Hyalomma dromedarii by chromatography on diethylaminoethyl (DEAE)-cellulose column. They were designated P1, P2, P3, P4 and P5 according to their elution order. P5 was found to be a potent thrombin inhibitor and purified by ultrafiltration through two centrifugal concentrators of 50 and 30kDa molecular weight cut-off (MWCO), respectively. The camel tick salivary gland thrombin inhibitor was purified 60.6 folds with a specific activity of 564units/mg protein. It turned out to be homogenous on native-PAGE with molecular weight of 36kDa as detected on 12% SDS-PAGE. It inhibits bovine thrombin competitively with K i value of 0.55μM. A task for the future will be the elucidation of this thrombin inhibitor structure to allow its application in thrombosis treatment.

Phlebotomus papatasi Yellow-Related and Apyrase Salivary Proteins Are Candidates for Vaccination against Human Cutaneous Leishmaniasis

Nowadays, there is no available vaccine for human leishmaniasis. Animal experiments demonstrate that pre-exposure to sand fly saliva confers protection against leishmaniasis. Our preceding work in humans indicates that Phlebotomus papatasi saliva induces the production of IL-10 by CD8+ T lymphocytes. The neutralization of IL-10 enhanced the activation of a T-cell CD4+ population-producing IFN-γ. Herein, we used a biochemical and functional genomics approach to identify the sand fly salivary components that are responsible for the activation of the T helper type 1 immune response in humans, therefore constituting potential vaccine candidates against leishmaniasis. Fractionated P.papatasi salivary extracts were first tested on T lymphocytes of immune donors. We confirmed that the CD4+ lymphocytes proliferate and produce IFN-γ in response to stimulation with the proteins of molecular weight >30 kDa. Peripheral blood mononuclear cells from immune donors were transfected with plasmids coding for the most abundant proteins from the P.papatasi salivary gland cDNA library. Our result showed that the "yellow related proteins," PPTSP42 and PPTSP44, and "apyrase," PPTSP36, are the proteins responsible for the aforementioned cellular immune response and IFN-γ production. Strikingly, PPTSP44 triggered the highest level of lymphocyte proliferation and IFN-γ production. Multiplex cytokine analysis confirmed the T helper type 1-polarized response induced by these proteins. Importantly, recombinant PPTSP44 validated the results observed with the DNA plasmid, further supporting that PPTSP44 constitutes a promising vaccine candidate against human leishmaniasis.

Analysis of Human Immune Response against Salivary Glands Protein Extract of Anopheles sundaicus. L in Malaria Endemic Area

Malaria is an infectious disease caused by Plasmodium, which is transmitted by Anopheles mosquitoes as vectors. Malaria transmission begins when an infected mosquito takes blood meal from healthy human. Mosquitoes will release parasite and components of saliva into the host's body. Saliva contains components (proteins) that affect the host's hemostasis and immune respose, such as vasomodulator and immunomodulators. Imunomudulator could act as immunosuppressive factors that can suppress nonspecific immune system of the host and modulate the change of T helper 1 (Th1) toward T helper 2 (Th2) response, which is advantageous for malaria parasite to infect human host. This research wanted to evaluate human immune respons in endemic area against salivary gland protein extract (SGPE) from its major malaria vector i.e. Anopheles sundaicus (An. sundaicus). Analysis of human immune response was conducted quantitatively by ELISA (Enzyme Link Immunosorbend Assay) towards IgG from human sera samples after cross reacted with SGPE. The results showed that exposures to An. sundaicus were able to induce high levels of IgG. IgG anti salivary proteins of An. sundaicus is higher than the levels of IgG anti salivary proteins of Ae. aegypti. Furthermore, the age group 11-40 years with the highest bites probability, had the highest IgG levels compared to other age groups.

Identification of a Tsal152-75 salivary synthetic peptide to monitor cattle exposure to tsetse flies.

BackgroundThe saliva of tsetse flies contains a cocktail of bioactive molecules inducing specific antibody responses in hosts exposed to bites. We have previously shown that an indirect-ELISA test using whole salivary extracts from Glossina morsitans submorsitans was able to discriminate between (i) cattle from tsetse infested and tsetse free areas and (ii) animals experimentally exposed to low or high numbers of tsetse flies. In the present study, our aim was to identify specific salivary synthetic peptides that could be used to develop simple immunoassays to measure cattle exposure to tsetse flies.MethodsIn a first step, 2D-electrophoresis immunoblotting, using sera from animals exposed to a variety of bloodsucking arthropods, was performed to identify specific salivary proteins recognised in cattle exposed to tsetse bites. Linear epitope prediction software and Blast analysis were then used to design synthetic peptides within the identified salivary proteins. Finally, candidate peptides were tested by indirect-ELISA on serum samples from tsetse infested and tsetse free areas, and from exposure experiments.ResultsThe combined immunoblotting and bioinformatics analyses led to the identification of five peptides carrying putative linear epitopes within two salivary proteins: the tsetse salivary gland protein 1 (Tsal1) and the Salivary Secreted Adenosine (SSA). Of these, two were synthesised and tested further based on the absence of sequence homology with other arthropods or pathogen species. IgG responses to the Tsal152–75 synthetic peptide were shown to be specific of tsetse exposure in both naturally and experimentally exposed hosts. Nevertheless, anti-Tsal152–75 IgG responses were absent in animals exposed to high tsetse biting rates.ConclusionsThese results suggest that Tsal152–75 specific antibodies represent a biomarker of low cattle exposure to tsetse fly. These results are discussed in the light of the other available tsetse saliva based-immunoassays and in the perspective of developing a simple serological tool for tsetse eradication campaigns to assess the tsetse free status or to detect tsetse reemergence in previously cleared areas.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-016-1414-8) contains supplementary material, which is available to authorized users.