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Antimicrobial Potential of Helicanthus elastica (Desr.) Danser - A less explored Indian mistletoe Growing on Mango Trees
Abstract and Figures
Helicanthus elastica (Desr.) Danser (Loranthaceae) is a less-known medicinally important mistletoe species occurring in India. It is used to check abortion, and also in vesical calculi and kidney affections. There are no detailed studies reporting the antimicrobial potential of this plant. Based on the traditional use and the rich phenolic composition of the whole plant, the antimicrobial property of the alcohol extract was analyzed and the results are outlined in the present paper. For the analysis, zone of inhibition, and minimum inhibitory concentration were used, and the total activity was assayed by standard methodologies. The antimicrobial activity was studied against bacteria like Aeromonas hydrophila, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pyogenes, Vibrio fischeri, and a fungus Candida albicans. Of the eight tested bacteria, the alcoholic extract of H. elastica was found to be active against K. pneumoniae, A. hydrophila, E. coli, and V. fischeri at concentration ranging from 250 to 500 μg/ml. C. albicans showed inhibition only at a concentration of 2000 μg/ml.
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... A recent report stated that ethanolic extract of Eugenia involucrata fruit revealed an effective super oxide free radical scavenging potential with a value of 25.8 ± 0.6 U/mL [40] . Alcoholic extract of Helicanthus elastica exhibited a strong inhibitory effect even at least concentrations (IC 50 of 37.42 g/mL) as reported earlier [41] . ...
Background
Oldenlandia corymbosa and Oldenlandia umbellata are well-known medicinal plants in various traditional systems of medicine and used to treat bronchitis, asthma, tuberculosis, constipation, and leprosy. We evaluated the phytochemical content, antioxidant potential, enzyme inhibitory action, anti-inflammatory, and antibacterial activities of the whole plant extracts of O. corymbosa and O. umbellata due to their therapeutic importance.
Methods
The phytochemical analysis includes qualitative analysis and quantification of total phenolics, flavonoids, tannins, flavonols, proanthocyanidins, and vitamin E. Enzyme inhibitory assays were studied using α-amylase and α-glucosidase enzymes and anti-inflammatory activity was determined by egg albumin denaturation assay. Antioxidant potential was estimated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethyl benzothiozoline-6-sulfonic acid) diammonium salt (ABTS), ferric reducing antioxidant power (FRAP), hydroxyl radical, superoxide, nitric oxide, metal chelating, and phosphomolybdenum assays. Minimum inhibitory concentrations of extracts were studied against ten bacterial strains by the microdilution method.
Results
The aqueous extract of O.umbellata showed a higher extract yield (5.0%). The highest amount of total phenolics and flavonoids were observed in the ethanolic extract of O.umbellata (77.23±0.46 mg GAE/g) and O.corymbosa (19.01±0.26 mg GAE/g). Ethanolic extract of O.umbellata (IC50 of 31.71±0.32 µg/mL) and aqueous extract of O.corymbosa (30.53±1.83 µg/mL) showed notable α-amylase inhibitory effect and petroleum ether extract of both plants observed good inhibition against α-glucosidase enzyme. Likewise, petroleum ether extract of O.umbellata (IC50 of 57.16±1.88 µg/mL) showed a moderate anti-inflammatory effect. In all extracts, considerable antioxidant potential was recorded specially with aqueous extract in the nitric oxide scavenging assay with an IC50 of 40.72±1.25 µg/mL. Ethanolic extract of O.umbellata and petroleum ether extract of O.corymbosa (MIC of 56.25 µg/mL) showed good antibiotic potency in lower concentrations which proves these two valuable herb's potential in herbal preparations.
Conclusions
The results of the study provide a basis for further studies aiming to evaluate the possibilities of using the O. umbellata and O. corymbosa as natural sources of antioxidants, enzyme inhibitory, and antibacterial agents. Further studies could be directed to exploit these plants in experimental animal models as potential pharmaceutical agents.
... Even though several plants with antimicrobial properties have been found, many remain unidentified. Many plants are being used as antibacterial or fungicidal agents [8]. Wound healing is an important biological process for preventing infections [9]. ...
Elytranthe parasitica, popularly known as Macrosolen parasiticus, is a hemiparasitic mistletoe species in India. It
has been traditionally used in veterinary medicine. The main objective of this research is to examine its chemical
constituents, and in vitro antibacterial, and cytotoxic activities. The qualitative screening of phytoconstituents revealed
the existence of tannins, phenols, glycosides, flavonols, sterols, saponins, terpenoids, carbohydrates, fixed oil, and fats.
Gas Chromatography-Mass Spectroscopy screening of stem methanol extract showed the appearance of 11 bioactive
phytoconstituents. Octadecenoic acid,4-hydroxybutyl ester (22.95%); 2H-1-Benzopyran-7-ol, 3,4-dihydro-5-methoxy2-phenyl- (21.90%); Oleic acid (14.18%); and 9-Hexadecenoic acid (10.59%) were the major identified compounds.
The methanolic stem extract exhibited considerable antibacterial activity and showed a good inhibition zone against
Xanthomonas campestris (19.83 ± 44 mm) followed by Salmonella typhi (15.50 ± 0.28 mm) and Enterococcus faecalis
(15.50 ± 0.28 mm) and the minimum inhibition zone showed against Escherichia coli (12.66 ± 0.33 mm). The methanolic
stem extract showed, moderate cytotoxicity on prostate, and pancreatic cancer cell lines at higher concentrations with
the inhibitory concentration at 50% growth values 372.27 ± 22.07 µg/mL and 443.33 ± 17.85 µg/mL, respectively, but
it has no cytotoxic effects on normal mouse embryo fibroblast cells (MEF-L239).
... Microorganisms, media, culture, and growth conditions Bacterial strains, Staphylococcus aureus MTCC-902, Bacillus subtilis MTCC-736, Klebsiella pneumoniae (MTCC-432), and Escherichia coli MTCC-443 and fungus strains, Candida albicans MTCC-183 and Aspergillus niger MTCC-1344 strains were used for this study to check the oil properties against them. Nutrient broth, Mueller-Hinton agar (MHA), and Sabouraud's dextrose agar (SDA) (HiMedia Laboratories) have been used for the bacterial and fungal growth followed by the standard protocols [17]. ...
Objective: In Sikkim (India), Seremna is a highly growing cultivar of Amomum subulatum at lower altitudes. Other popular cultivated varieties are Varlangy and Sawney in the same state but at different altitude. In this study, we evaluate the variation in essential oils, metabolites and antimicrobial activities among A. subulatum selected cultivars. Methods: The composition of essential oil of Varlangy, Seremna, and Sawney was analyzed using gas chromatography–mass spectrometry and comparative antimicrobial activity of oils was explored using agar well diffusion and agar dilution method. Results: The Seremna cultivar oil was shown the high content of major constituents (1,8-cineole) in comparison to others. Comparative minimum inhibitory concentrations and minimal bactericidal concentration (MBC) or minimal fungicidal concentration against two Gram-positive (Staphylococcus aureus and Bacillus subtilis), two Gram-negative (Klebsiella pneumoniae and Escherichia coli) bacteria, and two (Candida albicans and Aspergillus niger) fungi were determined. The oil of Seremna showed distinct antibacterial and antifungal activity against all the microorganisms except B. subtilis which showed resistance. Conclusion: The present findings concluded that the high content of the principal compound accelerates the antimicrobial activity of essential oils. The essential oil of Seremna could be a good antimicrobial agent and recommended in the case of infections.
... Helicanthus elastica (Desr.) Danser plant belonging to family Loranthaceae did not affect MRSA bacteria, but was more effective on gram-negative bacteria, especially Klebsiella pneumoniae (41 A large number of studies have been carried out on the identification of the antimicrobial effects of plant compounds on different microbial agents (97), which have also yielded favorable results. Wild plants have bioactive ingredients with potential activity against diseases associated with microorganisms (98). ...
Staphylococcus aureus is among the pathogens capable of developing a broad spectrum of infections in human beings. In addition to the hospital, the bacterium is present in the community and has a high resistance to antibiotics, which is also increasing on an ongoing basis. Resistance to β-lactam antibiotic family is one of the concerns about the bacterium that has encountered the treatment of such infections with difficulty. Due to the increased resistance and importance of this bacterium, new strategies are needed to control this pathogen. One of these approaches is the use of medicinal plants, which has attracted many researchers in the last decade. Several studies have been carried out or are being designed using various herbs to find active ingredients to deal with this bacterium. The aim of this study was to present the antibacterial activity of different medicinal plants and the effects of their active ingredients on methicillin-resistant and methicillin-sensitive S. aureus and to clarify the pathway to further studies in this regard.
... Helicanthus elastica (Desr.) Danser plant belonging to family Loranthaceae did not affect MRSA bacteria, but was more effective on gram-negative bacteria, especially Klebsiella pneumoniae (41 A large number of studies have been carried out on the identification of the antimicrobial effects of plant compounds on different microbial agents (97), which have also yielded favorable results. Wild plants have bioactive ingredients with potential activity against diseases associated with microorganisms (98). ...
Staphylococcus aureus is among the pathogens capable of developing a broad spectrum of infections in human beings. In addition to the hospital, the bacterium is present in the community and has a high resistance to antibiotics, which is also increasing on an ongoing basis. Resistance to β-lactam antibiotic family is one of the concerns about the bacterium that has encountered the treatment of such infections with difficulty. Due to the increased resistance and importance of this bacterium, new strategies are needed to control this pathogen. One of these approaches is the use of medicinal plants, which has attracted many researchers in the last decade. Several studies have been carried out or are being designed using various herbs to find active ingredients to deal with this bacterium. The aim of this study was to present the antibacterial activity of different medicinal plants and the effects of their active ingredients on methicillin-resistant and methicillin-sensitive S. aureus (MRSA, MSSA), and to clarify the pathway to further studies in this regard.
... Helicanthus elastica (Desr.) Danser plant belonging to family Loranthaceae did not affect MRSA bacteria, but was more effective on gram-negative bacteria, especially Klebsiella pneumoniae (41 A large number of studies have been carried out on the identification of the antimicrobial effects of plant compounds on different microbial agents (97), which have also yielded favorable results. Wild plants have bioactive ingredients with potential activity against diseases associated with microorganisms (98). ...
The rising trend of antibiotic-resistant infections around the world and the low antimicrobials development pipeline volume are necessitating continued efforts in the search for novel treatment options. The prominent success from fungi and bacteria as sources of antibiotics has long motivated widespread efforts in the search for antibacterial compounds from other natural sources including plants. This review aimed at appraising the approaches and outcomes from studies commissioned to evaluate the antibacterial activities of crude plant extracts and phytochemicals. Notably, the existing traditional practices provided the greatest motivation in screening for antibacterial properties of plants, whereby the need to validate ethnomedically reported potentials formed a crucial objective. Moreover, choices of experimental techniques to address different objectives were largely dependent on the prevailing access to resources, facilities, and technical skills. The lack of streamlined guidelines dedicated to testing of crude plant extracts have resulted into broad methodological variations and lack of a standardized classification system for antibacterial activities exhibited by plant extracts. Furthermore, libraries of 128 extracts from different plant species and 122 phytochemicals substantially active against the Escherichia coli and Klebsiella pneumoniae were assembled. This enabled the elucidation of existing patterns between the Minimum Inhibitory Concentrations (MICs) and studied plant families, plant tissues, extractants, phytochemical classes, as well as the rules of drug-likeness, penetration and accumulation. The insights provided in this review will potentially impart the ongoing efforts with improved experimental designs, inspire ideas for further studies and contribute to successful hunting for new antibacterial chemical scaffolds via in silico approaches.
Graphical abstract
Doğada bulunan birçok bitki, fenolik bileşik yönünden zengin olup doğal antioksidan ve antimikrobiyal özellikler taşımaktadır. Bu nedenle, bitkiler biyoteknolojik alanda önem kazanmaya ve kronik hastalıkların tedavisi için alternatif kaynak olarak tercih edilmeye başlanmıştır. Günümüzde önemli bir sağlık sorunu olan diyabet hastalığının tedavisinde anti-diyabetik özellik taşıyan bitkilerin kullanılabileceği düşünülmektedir. Bu özelliğinden dolayı bitkiler, son yıllarda araştırmacıların odak konusu haline gelmiştir. Bu bitkilerden birisi olan ve birçok hastalığın tedavisinde kullanılan ökse otunun (Viscum album), diyabet hastalığının tedavisi için de etkili olabileceği düşünülmüştür. Bu sebeple, bu çalışmada Artvin Arhavi bölgesinden toplanan armut ağacı üzerinde yetişen ökse otu bitkisinin üç farklı çözgen (kloroform, aseton, etanol) ile hazırlanmış ekstrelerinin fenolik ve flavonoid madde, antioksidan kapasite, antimikrobiyal aktivite ve enzim inhibisyon aktivite tayinleri yapılmıştır. Çalışmadan elde edilen sonuçlar göz önüne alındığında günümüzde yüksek bir biyolojik aktiviteye sahip olan ökse otu bitkisinin ilaç endüstrisinde kullanım potansiyelinin olduğu söylenebilir.
Helicanthes elasticus (Desv.) Danser is a common type of mistletoes of Indian origin. In Indian traditional and folklore medicines the plant is claimed to possess a range of medicinal values such as immunomod-ulator, anti-diabetic and anti-microbial properties. However, there is no experimental proof for its therapeutic claim. The aqueous and alcoholic extracts of H. elastica were evaluated for its immuno-modulatory effect on antibody formation against sheep red blood cells and on cell mediated immunity of immunological paw edema model. Ethanolic and aqueous extracts have shown dose dependent elevation in the antibody titer value in comparison to control group at 14th and 21st day of sensitization (**p < 0.01). There is a mild to moderate elevation were observed in the immunological paw edema at highest dose (400 mg/kg) during 21st day after sensitization. The histopathological observation shows that there is an increase in the white pulp of spleen and increased cellularity and formation of distinct germinal cells in lymph node. H. elasticus extracts possess marked antibody formation propensity without significant modification on cell mediated immunity.
The potential of methanolic leaves extract of H. elasticus in the mitigation of ulcer and inflammation was evaluated in this work. Ethanol and pylorus ligation induced rats were used for the screening of ulcer, whereas the anti-inflammatory activity against acute and chronic phases of inflammation was screened using carrageenan-induced paw edema and cotton pellet induced granuloma in rats. The H. elasticus (200 and 400 mg/kg p.o.) was administered to the ethanol and pylorus ligation induced rats. Gastric volume, pH, free acidity and total acidity were estimated in pylorus ligation induced ulcers of rats. Treatment with H. elasticus showed a reduction in ulcer index against ethanol and pylorus ligation induced ulcerations. The antiulcer activity may be due to the antisecretory and cytoprotective effects of the extract. Moreover, it also showed a highly significant (P ≤ 0.001) reduction in carrageenan and cotton pellet induced inflammations. This investigation suggests that H. elasticus leaves possess anti-inflammatory activity and promotes ulcer protection.
OBJECTIVE: To evaluate the antibacterial potential of aqueous and acetone extracts of galls of Quercus infectoria by determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values. MATERIALS AND METHODS: The extracts from the galls of Q. infectoria at 10 mg/ml were screened against three Gram-positive bacteria ( Staphylococcus aureus ATCC 25923, Staphylococcus epidermidis and Bacillus subtilis ) and three Gram-negative bacteria ( Escherichia coli NCTC 12079 serotype O157:H7, Salmonella typhimurium NCTC 74 and Pseudomonas aeruginosa ATCC 27853). The MIC of the extracts were then determined using the twofold serial microdilution technique at a concentration ranging from 5 mg/ml to 0.0024 mg/ml. The MBC values were finally obtained from the MIC microtiter wells which showed no turbidity after 24 hrs of incubation by subculturing method. RESULTS: Out of the six bacterial species tested, S. aureus was the most susceptible. On the other hand, the extracts showed weak inhibitory effect against S. epidermidis, B. subtilis , S. typhimurium and P. aeruginosa while there was no inhibition zone observed for E. coli O157. The MIC values of the extracts ranged from 0.0781 mg/ml to 1.25 mg/ml whereas the MBC values ranged from 0.3125 mg/ml to 2.50 mg/ml. The MBC values of aqueous extract against S. aureus and S. typhimurium were higher than their MIC values. The MBC value of acetone extract against S. aureus was also higher than its MIC value. Interestingly, however, the MIC and MBC values of acetone extract against S. typhimurium were the same (1.25 mg/ml). CONCLUSION: The aqueous and acetone extracts displayed similarities in their antimicrobial activity on the bacterial species and as such, the galls of Quercus infectoria are potentially good source of antimicrobial agents.
Group A streptococci are model extracellular gram-positive pathogens responsible for pharyngitis, impetigo, rheumatic fever, and acute glomerulonephritis. A resurgence of invasive streptococcal diseases and rheumatic fever has appeared in outbreaks over the past 10 years, with a predominant M1 serotype as well as others identified with the outbreaks. emm (M protein) gene sequencing has changed serotyping, and new virulence genes and new virulence regulatory networks have been defined. The emm gene superfamily has expanded to include antiphagocytic molecules and immunoglobulin-binding proteins with common structural features. At least nine superantigens have been characterized, all of which may contribute to toxic streptococcal syndrome. An emerging theme is the dichotomy between skin and throat strains in their epidemiology and genetic makeup. Eleven adhesins have been reported, and surface plasmin-binding proteins have been defined. The strong resistance of the group A streptococcus to phagocytosis is related to factor H and fibrinogen binding by M protein and to disarming complement component C5a by the C5a peptidase. Molecular mimicry appears to play a role in autoimmune mechanisms involved in rheumatic fever, while nephritis strain-associated proteins may lead to immune-mediated acute glomerulonephritis. Vaccine strategies have focused on recombinant M protein and C5a peptidase vaccines, and mucosal vaccine delivery systems are under investigation.
Field survey; macro-microscopy; physicochemical analysis – heavy metal and microbial load; phytochemical examination – isolation of 7 marker compounds; molecular fingerprinting by RAPD; chemical fingerprinting by HPTLC and HPLC; neutraceutical analysis – proximate composition, vitamins and trace elements; antimicrobial activity; in-vitro antioxidant activity; acute toxicity by OECD guideline 423; heptatoprotective activity by paracetamol induced hepatotoxicity model; and immunomodulatory activity by SRBC model and immunological paw edema of Helicanthus elastica (Desr) Danser
As part of an effort designed to develop antimicrobial food formulations that will protect both the food and the consumer against pathogenic bacteria and viruses, we evaluated the bactericidal activities of ~300 plant essential oils, oil constituents, phenolic benzaldehydes, and benzoic acids, and polyphenolic catechins against the foodborne pathogens Bacillus cereus, Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica, and Staphylococcus aureus. This brief overview summarizes some of our results. The data show that many of these phytochemicals are highly active against both non-resistant and antibiotic-resistant bacteria a pH 7 buffer and in a pH 3.7 apple juice. To help define the mechanism of antibacterial effects of phytochemicals, we also describe exploratory studies on the spontaneous fluorescence (autofluorescence) and ATP release of E. coli, to assess the sub-lethal effects of carvacrol. Future studies should define their antimicrobial effectiveness in human foods and animal feed and as disinfectants of surfaces of fruits and vegetables and of non-food items such as cutting boards.
To investigate the effect of seven wine phenolic compounds and six oenological phenolic extracts on the growth of pathogenic bacteria associated with respiratory diseases (Pseudomonas aeruginosa, Staphylococcus aureus, Moraxella catarrhalis, Enterococcus faecalis, Streptococcus sp Group F, Streptococcus agalactiae and Streptococcus pneumoniae).
Antimicrobial activity was determined using a microdilution method and quantified as IC(50) . Mor. catarrhalis was the most susceptible specie to phenolic compounds and extracts. Gallic acid and ethyl gallate were the compounds that showed the greatest antimicrobial activity. Regarding phenolic extracts, GSE (grape seed extract) and GSE-O (oligomeric-rich fraction from GSE) were the ones that displayed the strongest antimicrobial effects.
Results highlight the antimicrobial properties of wine phenolic compounds and oenological extracts against potential respiratory pathogens. The antimicrobial activity of wine phenolic compounds was influenced by the type of phenolic compounds. Gram-negative bacteria were more susceptible than Gram-positive bacteria to the action of phenolic compounds and extracts; however, the effect was species-dependent.
The ability to inhibit the growth of respiratory pathogenic bacteria as shown by several wine phenolic compounds and oenological extracts warrants further investigations to explore the use of grape and wine preparations in oral hygiene.
Not all patients infected with NDM-1-positive bacteria have a history of hospital admission in India, and extended-spectrum β-lactamases are known to be circulating in the Indian community. We therefore measured the prevalence of the NDM-1 gene in drinking water and seepage samples in New Delhi.
Swabs absorbing about 100 μL of seepage water (ie, water pools in streets or rivulets) and 15 mL samples of public tap water were collected from sites within a 12 km radius of central New Delhi, with each site photographed and documented. Samples were transported to the UK and tested for the presence of the NDM-1 gene, bla(NDM-1), by PCR and DNA probing. As a control group, 100 μL sewage effluent samples were taken from the Cardiff Wastewater Treatment Works, Tremorfa, Wales. Bacteria from all samples were recovered and examined for bla(NDM-1) by PCR and sequencing. We identified NDM-1-positive isolates, undertook susceptibility testing, and, where appropriate, typed the isolates. We undertook Inc typing on bla(NDM-1)-positive plasmids. Transconjugants were created to assess plasmid transfer frequency and its relation to temperature.
From Sept 26 to Oct 10, 2010, 171 seepage samples and 50 tap water samples from New Delhi and 70 sewage effluent samples from Cardiff Wastewater Treatment Works were collected. We detected bla(NDM-1) in two of 50 drinking-water samples and 51 of 171 seepage samples from New Delhi; the gene was not found in any sample from Cardiff. Bacteria with bla(NDM-1) were grown from 12 of 171 seepage samples and two of 50 water samples, and included 11 species in which NDM-1 has not previously been reported, including Shigella boydii and Vibrio cholerae. Carriage by enterobacteria, aeromonads, and V cholera was stable, generally transmissible, and associated with resistance patterns typical for NDM-1; carriage by non-fermenters was unstable in many cases and not associated with typical resistance. 20 strains of bacteria were found in the samples, 12 of which carried bla(NDM-1) on plasmids, which ranged in size from 140 to 400 kb. Isolates of Aeromonas caviae and V cholerae carried bla(NDM-1) on chromosomes. Conjugative transfer was more common at 30°C than at 25°C or 37°C.
The presence of NDM-1 β-lactamase-producing bacteria in environmental samples in New Delhi has important implications for people living in the city who are reliant on public water and sanitation facilities. International surveillance of resistance, incorporating environmental sampling as well as examination of clinical isolates, needs to be established as a priority.
European Union.
Extracts from plants of Loranthaceae family collected from 15 host trees were screened for their cytocidal activity to tumour cells. Biologically active extracts prepared from Helicanthis elasticus grown on Mangifera indica and Citrus maxima (host trees) were partially purified by the gel filtration method. The purified material was found to be cytotoxic in vitro and reduced solid and ascites tumours in mice when given either simultaneously or prophylactically. The partially purified material was found to be a protein with a molecular weight of approximately 80,000 Da.
Group A streptococci are model extracellular gram-positive pathogens responsible for pharyngitis, impetigo, rheumatic fever, and acute glomerulonephritis. A resurgence of invasive streptococcal diseases and rheumatic fever has appeared in outbreaks over the past 10 years, with a predominant M1 serotype as well as others identified with the outbreaks. emm (M protein) gene sequencing has changed serotyping, and new virulence genes and new virulence regulatory networks have been defined. The emm gene superfamily has expanded to include antiphagocytic molecules and immunoglobulin-binding proteins with common structural features. At least nine superantigens have been characterized, all of which may contribute to toxic streptococcal syndrome. An emerging theme is the dichotomy between skin and throat strains in their epidemiology and genetic makeup. Eleven adhesins have been reported, and surface plasmin-binding proteins have been defined. The strong resistance of the group A streptococcus to phagocytosis is related to factor H and fibrinogen binding by M protein and to disarming complement component C5a by the C5a peptidase. Molecular mimicry appears to play a role in autoimmune mechanisms involved in rheumatic fever, while nephritis strain-associated proteins may lead to immune-mediated acute glomerulonephritis. Vaccine strategies have focused on recombinant M protein and C5a peptidase vaccines, and mucosal vaccine delivery systems are under investigation.