Phlebotomus argentipes is a predominant vector of Leishmania donovani, the protozoan parasite causing visceral leishmaniasis in the Indian subcontinent. In hosts bitten by P. argentipes, sand fly saliva elicits the production of specific anti-salivary protein antibodies. Here, we have utilised these antibodies as markers of human exposure to P. argentipes in a visceral leishmaniasis endemic area in Pabna district, Bangladesh. The use of whole salivary gland homogenate as an antigen to detect these antibodies has several limitations, therefore it is being superseded by the use of specific recombinant salivary proteins. We have identified three major P. argentipes salivary antigenic proteins recognised by sera of bitten humans, expressed them in a recombinant form (rPagSP04, rPagSP05 and rPagSP06) and tested their applicability in ELISA and immunoblot. One of them, PpSP32-like protein rPagSP06, was identified as the most promising antigen, showing highest resemblance and correlation with the IgG response to P. argentipes salivary gland homogenate. Furthermore, we have validated the applicability of rPagSP06 in a large cohort of 585 individuals and obtained a high correlation coefficient for anti-rPagSP06 and anti-P. argentipes saliva IgG responses. The anti-rPagSP06 and anti-P. argentipes salivary gland homogenate IgG responses followed a similar right-skewed distribution. This is the first report of screening human sera for anti-P. argentipes saliva antibodies using recombinant salivary protein. The rPagSP06 was proven to be a valid antigen for screening human sera for exposure to P. argentipes bites in a visceral leishmaniasis endemic area.
- Klíčová slova
- Bangladesh, IgG antibodies, Leishmania donovani, Marker of exposure, Phlebotomus argentipes, Salivary glands,
- MeSH
- hmyzí proteiny * imunologie MeSH
- kousnutí a bodnutí epidemiologie MeSH
- Leishmania donovani MeSH
- lidé MeSH
- Phlebotomus * MeSH
- slinné proteiny a peptidy * imunologie MeSH
- sliny MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Bangladéš epidemiologie MeSH
- Názvy látek
- hmyzí proteiny * MeSH
- slinné proteiny a peptidy * MeSH
In Europe, Ixodes ricinus is the most important vector of human infectious diseases, most notably Lyme borreliosis and tick-borne encephalitis virus. Multiple non-natural hosts of I. ricinus have shown to develop immunity after repeated tick bites. Tick immunity has also been shown to impair B. burgdorferi transmission. Most interestingly, multiple tick bites reduced the likelihood of contracting Lyme borreliosis in humans. A vaccine that mimics tick immunity could therefore potentially prevent Lyme borreliosis in humans. A yeast surface display library (YSD) of nymphal I. ricinus salivary gland genes expressed at 24, 48 and 72 h into tick feeding was constructed and probed with antibodies from humans repeatedly bitten by ticks, identifying twelve immunoreactive tick salivary gland proteins (TSGPs). From these, three proteins were selected for vaccination studies. An exploratory vaccination study in cattle showed an anti-tick effect when all three antigens were combined. However, immunization of rabbits did not provide equivalent levels of protection. Our results show that YSD is a powerful tool to identify immunodominant antigens in humans exposed to tick bites, yet vaccination with the three selected TSGPs did not provide protection in the present form. Future efforts will focus on exploring the biological functions of these proteins, consider alternative systems for recombinant protein generation and vaccination platforms and assess the potential of the other identified immunogenic TSGPs.
- MeSH
- antigeny krev imunologie izolace a purifikace MeSH
- Borrelia burgdorferi izolace a purifikace MeSH
- imunizace MeSH
- infestace klíšťaty imunologie parazitologie MeSH
- klíště imunologie MeSH
- kousnutí klíštětem imunologie MeSH
- králíci MeSH
- lidé MeSH
- lymeská nemoc krev parazitologie přenos MeSH
- metody zobrazení buněčného povrchu metody MeSH
- peptidová knihovna MeSH
- peptidové fragmenty imunologie MeSH
- Saccharomyces cerevisiae MeSH
- skot MeSH
- slinné proteiny a peptidy imunologie MeSH
- slinné žlázy imunologie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- lidé MeSH
- mužské pohlaví MeSH
- skot MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- antigeny MeSH
- peptidová knihovna MeSH
- peptidové fragmenty MeSH
- slinné proteiny a peptidy MeSH
Saliva contains possible biomarkers that are associated with dental caries. The present study aimed to analyse differences in the abundance of proteins in the saliva between caries-positive (CP; N = 15) and caries-free (CF; N = 12) males and to compare differences in the abundance of proteins between two saliva sample fractions (supernatant and pellet). We found 14 differently significantly expressed proteins in the CF group when comparing the supernatant fractions of the CP and CF groups, and three proteins in the pellet fractions had significantly higher expression in the CP group. Our results indicate very specific protein compositions of the saliva in relation to dental caries resistance (the saliva of the CP group mainly contained pellet proteins and the saliva of the CF group mainly contained supernatant proteins). This was the first time that the saliva pellet fraction was analysed in relation to the dental caries status. We detected specific calcium-binding proteins that could have decalcified enamel in the saliva pellet of the CP group. We also observed significantly up-regulated immune proteins in the saliva supernatant of the CF group that could play an important role in the caries prevention. The particular protein compositions of the saliva pellet and supernatant in the groups with different susceptibilities to tooth decay is a promising finding for future research.
- MeSH
- lidé MeSH
- náchylnost k zubnímu kazu * MeSH
- proteomika * MeSH
- slinné proteiny a peptidy analýza imunologie metabolismus MeSH
- sliny chemie imunologie metabolismus MeSH
- zubní kaz imunologie metabolismus prevence a kontrola MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- slinné proteiny a peptidy MeSH
BACKGROUND: In endemic areas of zoonotic leishmaniosis caused by L. infantum, early detection of Leishmania infection in dogs is essential to control the dissemination of the parasite to humans. The aim of this study was to evaluate the serological and/or molecular diagnostic performance of minimally and non-invasive samples (conjunctiva cells (CS) and peripheral blood (PB)) for monitoring Leishmania infection/exposure to Phlebotomus perniciosus salivary antigens in dogs at the beginning and the end of sand fly seasonal activity (May and October, respectively) and to assess associated risks factors. METHODS: A total of 208 sheltered dogs from endemic areas of leishmaniosis were screened. Leishmania DNA detection in PB on filter paper and CS was performed by nested-PCR (nPCR), while the detection of anti-Leishmania antibodies was performed using IFAT and ELISA. The exposure to P. perniciosus salivary antigens (SGH, rSP01 and rSP03B + rSP01) was measured by ELISA. RESULTS: Ninety-seven (46.6%) and 116 (55.8%) of the 208 dogs were positive to Leishmania antibodies or DNA by at least one test at the beginning and end of the sand fly season, respectively. IFAT and ELISA presented a substantial agreement in the serodiagnosis of leishmaniosis. Discrepant PB nPCR results were obtained between sampling points. Leishmania DNA was detected in CS of 72 dogs at the end of the phlebotomine season. The presence of antibodies to the parasite measured by ELISA was significantly higher in dogs presenting clinical signs compatible with leishmaniosis at both sampling points. Phlebotomus perniciosus salivary antibodies were detected in 179 (86.1%) and 198 (95.2%) of the screened dogs at the beginning and end of the phlebotomine season, respectively. CONCLUSIONS: The association between ELISA positivity and clinical signs suggests its usefulness to confirm a clinical suspicion. CS nPCR seems to be an effective and non-invasive method for assessing early exposure to the parasite. PB nPCR should not be used as the sole diagnostic tool to monitor Leishmania infection. The correlation between the levels of antibodies to P. perniciosus saliva and Leishmania antibodies suggests the use of a humoral response to sand fly salivary antigens as biomarkers of L. infantum infection.
- Klíčová slova
- Blood, Conjunctival cells, Dog, Exposure, L. infantum, Phlebotomus pernicious, Saliva,
- MeSH
- antigeny protozoální imunologie MeSH
- endemické nemoci prevence a kontrola MeSH
- hmyz - vektory parazitologie MeSH
- hmyzí proteiny imunologie MeSH
- imunoglobulin G krev MeSH
- konjunktiva cytologie parazitologie MeSH
- kousnutí a bodnutí hmyzem MeSH
- Leishmania infantum izolace a purifikace MeSH
- leishmanióza krev imunologie veterinární MeSH
- nemoci psů parazitologie prevence a kontrola přenos MeSH
- Phlebotomus parazitologie MeSH
- protilátky protozoální krev MeSH
- protozoální proteiny imunologie MeSH
- psi MeSH
- rizikové faktory MeSH
- sérologické testy MeSH
- slinné proteiny a peptidy imunologie MeSH
- zvířata MeSH
- Check Tag
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antigeny protozoální MeSH
- hmyzí proteiny MeSH
- imunoglobulin G MeSH
- protilátky protozoální MeSH
- protozoální proteiny MeSH
- slinné proteiny a peptidy MeSH
BACKGROUND: Canine leishmaniosis caused by Leishmania infantum is a neglected zoonosis transmitted by sand flies like Phlebotomus perniciosus. Clinical signs and disease susceptibility vary according to various factors, including host immune response and breed. In particular, Ibizan hounds appear more resistant. This immunocompetence could be attributed to a more frequent exposure to uninfected sand flies, eliciting a stronger anti-sand fly saliva antibody response. METHODS: This study aimed to investigate the prevalence of anti-P. perniciosus saliva antibodies in Ibizan hounds and dogs of other breeds in the Leishmania-endemic area of Mallorca, Spain, and to correlate these antibody levels with clinical, immunological and parasitological parameters. Anti-sand fly saliva IgG was examined in 47 Ibizan hounds and 45 dogs of other breeds using three methods: P. perniciosus whole salivary gland homogenate (SGH) ELISA; recombinant protein rSP03B ELISA; and rSP03B rapid tests (RT). Additionally, diagnostic performance was evaluated between methods. RESULTS: Results indicate significantly higher anti-SGH antibodies (P = 0.0061) and a trend for more positive SGH ELISA and RT results in Ibizan hounds compared to other breeds. General linear model analysis also found breed to be a significant factor in SGH ELISA units and a marginally significant factor in RT result. Although infection rates were similar between groups, Ibizan hounds included significantly more IFN-γ producers (P = 0.0122) and papular dermatitis cases (P < 0.0001). Older age and L. infantum seropositivity were also considered significant factors in sand fly saliva antibody levels according to at least one test. Fair agreement was found between all three tests, with the highest value between SGH and rSP03B RT. CONCLUSIONS: To our knowledge, this is the first study elaborating the relationship between anti-P. perniciosus saliva antibodies and extensive clinical data in dogs in an endemic area. Our results suggest that Ibizan hounds experience a higher frequency of exposure to sand flies and have a stronger cellular immune response to L. infantum infection than other breed dogs. Additional sampling is needed to confirm results, but anti-P. perniciosus saliva antibodies appear to negatively correlate with susceptibility to L. infantum infection and could possibly contribute to the resistance observed in Ibizan hounds.
- Klíčová slova
- Anti-sand fly saliva antibodies, Canine leishmaniosis, Ibizan hounds, Leishmania infantum, Papular dermatitis, Phlebotomus perniciosus, rSP03B,
- MeSH
- chov MeSH
- endemické nemoci MeSH
- hmyzí proteiny imunologie MeSH
- imunoglobulin G imunologie MeSH
- leishmanióza imunologie veterinární MeSH
- náchylnost k nemoci MeSH
- nemoci psů imunologie parazitologie MeSH
- Phlebotomus imunologie MeSH
- psi MeSH
- slinné proteiny a peptidy imunologie MeSH
- sliny imunologie MeSH
- zoonózy parazitologie přenos MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Španělsko MeSH
- Názvy látek
- hmyzí proteiny MeSH
- imunoglobulin G MeSH
- slinné proteiny a peptidy MeSH
Ticks are a growing concern to human and animal health worldwide and they are leading vectors of arthropod-borne pathogens in the United States. Ticks are pool blood feeders that can attach to the host skin for days to weeks using their saliva to counteract the host defenses. Tick saliva, as in other hematophagous arthropods, contains pharmacological and immunological active compounds, which modulate local and systemic immune responses and induce antibody production. In the present study, we explore differences in the salivary gland extract (SGE) protein content of Amblyomma americanum ticks raised in a laboratory colony (CT) vs. those collected in the field (FT). First, we measured the IgG antibody levels against SGE in healthy volunteers residing in Kansas. ELISA test showed higher IgG antibody levels when using the SGE from CT as antigen. Interestingly, antibody levels against both, CT-SGE and FT-SGE, were high in the warm months (May-June) and decreased in the cold months (September-November). Immunoblot testing revealed a set of different immunogenic bands for each group of ticks and mass spectrometry data revealed differences in at 19 proteins specifically identified in the CT-SGE group and 20 from the FT-SGE group. Our results suggest that differences in the salivary proteins between CT-SGE and FT-SGE may explain the differential immune responses observed in this study.
- Klíčová slova
- Amblyomma americanum, antibodies, human immune response, lone star tick, salivary proteins, seasonal response,
- MeSH
- antigeny imunologie MeSH
- buněčné linie MeSH
- cytokiny genetika metabolismus MeSH
- dospělí MeSH
- hmyzí proteiny imunologie MeSH
- infestace klíšťaty genetika imunologie MeSH
- interakce hostitele a parazita imunologie MeSH
- klíšťata imunologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- slinné proteiny a peptidy imunologie MeSH
- slinné žlázy imunologie MeSH
- zvířata MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Názvy látek
- antigeny MeSH
- cytokiny MeSH
- hmyzí proteiny MeSH
- slinné proteiny a peptidy MeSH
BACKGROUND: Hosts repeatedly bitten by sand flies develop antibodies against sand fly saliva and screening of these immunoglobulins can be employed to estimate the risk of Leishmania transmission, to indicate the feeding preferences of sand flies, or to evaluate the effectiveness of vector control campaigns. Previously, antibodies to sand fly saliva were detected using whole salivary gland homogenate (SGH) or recombinant proteins, both of which also have their disadvantages. This is the first study on sand flies where short peptides designed based on salivary antigens were successfully utilized for antibody screening. METHODOLOGY/PRINCIPAL FINDINGS: Specific IgG was studied in hosts naturally exposed to Phlebotomus orientalis, the main vector of Leishmania donovani in East Africa. Four peptides were designed by the commercial program EpiQuest-B, based on the sequences of the two most promising salivary antigens, yellow-related protein and ParSP25-like protein. Short amino acid peptides were synthesised and modified for ELISA experiments. Specific anti-P. orientalis IgG was detected in sera of dogs, goats, and sheep from Ethiopia. The peptide OR24 P2 was shown to be suitable for antibody screening; it correlated positively with SGH and its specificity and sensitivity were comparable or even better than that of previously published recombinant proteins. CONCLUSIONS/SIGNIFICANCE: OR24 P2, the peptide based on salivary antigen of P. orientalis, was shown to be a valuable tool for antibody screening of domestic animals naturally exposed to P. orientalis. We suggest the application of this promising methodology using species-specific short peptides to other sand fly-host combinations.
- MeSH
- ELISA metody MeSH
- imunoglobulin G krev MeSH
- kozy MeSH
- ovce MeSH
- peptidy imunologie MeSH
- Phlebotomus imunologie MeSH
- plošný screening metody MeSH
- protilátky krev MeSH
- psi MeSH
- senzitivita a specificita MeSH
- slinné proteiny a peptidy imunologie MeSH
- zvířata MeSH
- Check Tag
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Etiopie MeSH
- Názvy látek
- imunoglobulin G MeSH
- peptidy MeSH
- protilátky MeSH
- slinné proteiny a peptidy MeSH
BACKGROUND: Phlebotomus orientalis is a vector of Leishmania donovani, the causative agent of life threatening visceral leishmaniasis spread in Eastern Africa. During blood-feeding, sand fly females salivate into the skin of the host. Sand fly saliva contains a large variety of proteins, some of which elicit specific antibody responses in the bitten hosts. To evaluate the exposure to sand fly bites in human populations from disease endemic areas, we tested the antibody reactions of volunteers' sera against recombinant P. orientalis salivary antigens. METHODOLOGY/PRINCIPAL FINDINGS: Recombinant proteins derived from sequence data on P. orientalis secreted salivary proteins, were produced using either bacterial (five proteins) or mammalian (four proteins) expression systems and tested as antigens applicable for detection of anti-P. orientalis IgG in human sera. Using these recombinant proteins, human sera from Sudan and Ethiopia, countries endemic for visceral leishmaniasis, were screened by ELISA and immunoblotting to identify the potential markers of exposure to P. orientalis bites. Two recombinant proteins; mAG5 and mYEL1, were identified as the most promising antigens showing high correlation coefficients as well as good specificity in comparison to the whole sand fly salivary gland homogenate. Combination of both proteins led to a further increase of correlation coefficients as well as both positive and negative predictive values of P. orientalis exposure. CONCLUSIONS/SIGNIFICANCE: This is the first report of screening human sera for anti-P. orientalis antibodies using recombinant salivary proteins. The recombinant salivary proteins mYEL1 and mAG5 proved to be valid antigens for screening human sera from both Sudan and Ethiopia for exposure to P. orientalis bites. The utilization of equal amounts of these two proteins significantly increased the capability to detect anti-P. orientalis antibody responses.
- MeSH
- ELISA MeSH
- hmyzí proteiny genetika imunologie MeSH
- imunoglobulin G imunologie MeSH
- kousnutí a bodnutí hmyzem imunologie parazitologie MeSH
- lidé MeSH
- Phlebotomus genetika imunologie fyziologie MeSH
- rekombinantní proteiny genetika imunologie MeSH
- slinné proteiny a peptidy genetika imunologie MeSH
- sliny imunologie MeSH
- tvorba protilátek MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- východní Afrika MeSH
- Názvy látek
- hmyzí proteiny MeSH
- imunoglobulin G MeSH
- rekombinantní proteiny MeSH
- slinné proteiny a peptidy MeSH
BACKGROUND: Canine leishmaniosis (CanL) is an important zoonotic parasitic disease, endemic in the Mediterranean basin. In this region, transmission of Leishmania infantum, the etiological agent of CanL, is through the bite of phlebotomine sand flies. Therefore, monitoring host-vector contact represents an important epidemiological tool, and could be used to assess the effectiveness of vector-control programmes in endemic areas. Previous studies have shown that canine antibodies against the saliva of phlebotomine sand flies are specific markers of exposure to Leishmania vectors. However, this method needs to be further validated in natural heterogeneous dog populations living in CanL endemic areas. METHODS: In this study, 176 dogs living in 12 different locations of an L. infantum endemic area in north-east Spain were followed for 14 months. Blood samples were taken at 5 pre-determined time points (February, August and October 2016; January and April 2017) to assess the canine humoral immune response to whole salivary gland homogenate (SGH) and to the single salivary 43 kDa yellow-related recombinant protein (rSP03B) of Phlebotomus perniciosus, a proven vector of L. infantum naturally present in this region. Simultaneously, in all dogs, L. infantum infection status was assessed by serology. The relationship between anti-SGH and anti-rSP03B antibodies with the sampling month, L. infantum infection and the location was tested by fitting multilevel linear regression models. RESULTS: The dynamics of canine anti-saliva IgG for both SGH and rSP03B followed the expected trends of P. perniciosus activity in the region. Statistically significant associations were detected for both salivary antigens between vector exposure and sampling month or dog seropositivity to L. infantum. The correlation between canine antibodies against SGH and rSP03B was moderate. CONCLUSIONS: Our results confirm the frequent presence of CanL vectors in the study area in Spain and support the applicability of SGH- and rSP03B-based ELISA tests to study canine exposure to P. perniciosus in L. infantum endemic areas.
- Klíčová slova
- Canine leishmaniosis, Longitudinal study, Markers of exposure, North-east Spain, Phlebotomus perniciosus, Saliva proteins,
- MeSH
- endemické nemoci veterinární MeSH
- hmyz - vektory parazitologie MeSH
- humorální imunita MeSH
- imunoglobulin G analýza MeSH
- Leishmania infantum izolace a purifikace MeSH
- leishmanióza krev parazitologie veterinární MeSH
- longitudinální studie MeSH
- nemoci psů diagnóza imunologie parazitologie MeSH
- Phlebotomus imunologie MeSH
- protilátky protozoální krev MeSH
- protilátky krev MeSH
- psi imunologie parazitologie MeSH
- roční období MeSH
- slinné proteiny a peptidy imunologie MeSH
- slinné žlázy chemie parazitologie MeSH
- sliny imunologie mikrobiologie parazitologie MeSH
- zvířata MeSH
- Check Tag
- psi imunologie parazitologie MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Španělsko epidemiologie MeSH
- Názvy látek
- imunoglobulin G MeSH
- protilátky protozoální MeSH
- protilátky MeSH
- slinné proteiny a peptidy MeSH
BACKGROUND: Leishmaniases are parasitic diseases present worldwide that are transmitted to the vertebrate host by the bite of an infected sand fly during a blood feeding. Phlebotomine sand flies inoculate into the mammalian host Leishmania parasites embedded in promastigote secretory gel (PSG) with saliva, which is composed of a diverse group of molecules with pharmacological and immunomodulatory properties. METHODS AND FINDINGS: In this review, we focus on 3 main aspects of sand fly salivary molecules: (1) structure and composition of salivary glands, including the properties of salivary molecules related to hemostasis and blood feeding, (2) immunomodulatory properties of salivary molecules and the diverse impacts of these molecules on leishmaniasis, ranging from disease exacerbation to vaccine development, and (3) use of salivary molecules for field applications, including monitoring host exposure to sand flies and the risk of Leishmania transmission. Studies showed interesting differences between salivary proteins of Phlebotomus and Lutzomyia species, however, no data were ever published on salivary proteins of Sergentomyia species. CONCLUSIONS: In the last 15 years, numerous studies have characterized sand fly salivary proteins and, in parallel, have addressed the impact of such molecules on the biology of the host-sand fly-parasite interaction. The results obtained shall pave the way for the development of field-application tools that could contribute to the management of leishmaniasis in endemic areas.
- MeSH
- Leishmania imunologie MeSH
- Psychodidae parazitologie fyziologie MeSH
- slinné proteiny a peptidy imunologie metabolismus MeSH
- sliny imunologie parazitologie MeSH
- stravovací zvyklosti * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- slinné proteiny a peptidy MeSH