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PubMed2006

Hyaluronic acid inhibits the adherence and growth of monolayer keratinocytes but does not affect the growth of keratinocyte epithelium.

Hyaluronic acid (HA) is involved in epidermal biology but evidence for its functional significance is sparse. In this study, low-calcium monolayer and high-calcium epithelium cultures of human keratinocytes were used to study the effect of up to four different HA preparations on keratinocyte growth and on the adherence of proliferating keratinocytes onto the plastic surface coated with different matrix proteins. In suboptimally growing monolayer culture, up to 1,000 microg/ml rooster comb HA and streptococcus equi HA inhibited keratinocyte growth. Instead, all HA preparations tested did not affect the growth and migration of keratinocyte epithelium using optimal or suboptimal growth conditions. In the cell adherence assays, up to 1,000 microg/ml rooster comb HA and streptococcus equi HA inhibited the keratinocyte adherence onto the fibronectin- and collagen-coated substratum. In contrast to other HA preparations, HA from human umbilical cord did not affect the growth of monolayer keratinocytes and it increased markedly the cell adherence onto the collagen-coated substratum. This increase, however, can be attributed to chonroitin sulphate proteoglycan contaminant present in this HA preparation. In conclusion, HA can inhibit the growth and adherence of proliferating monolayer keratinocytes, but it has no apparent effect on the growth and migration of keratinocyte epithelium.

Adjuvants, Immunologic↗
PubMed2003

Two novel superantigens found in both group A and group C Streptococcus.

Two novel streptococcal superantigen genes (speL(Se) and speM(Se)) were identified from the Streptococcus equi genome database at the Sanger Center. Genotyping of 8 S. equi isolates and 40 Streptococcus pyogenes isolates resulted in the detection of the orthologous genes speL and speM in a restricted number of S. pyogenes isolates (15 and 5%, respectively). Surprisingly, the novel superantigen genes could not be found in any of the analyzed S. equi isolates. The results suggest that both genes are located on a mobile element that enables gene transfer between individual isolates and between streptococci from different Lancefield groups. S. equi pyrogenic exotoxin L (SPE-L(Se))/streptococcal pyrogenic exotoxin L (SPE-L) and SPE-M(Se)/SPE-M are most closely related to SMEZ, SPE-C, SPE-G, and SPE-J, but build a separate branch within this group. Recombinant SPE-L (rSPE-L) and rSPE-M were highly mitogenic for human peripheral blood lymphocytes, with half-maximum responses at 1 and 10 pg/ml, respectively. The results from competitive binding experiments suggest that both proteins bind major histocompatibility complex class II at the beta-chain, but not at the alpha-chain. The most common targets for both toxins were human Vbeta1.1 expressing T cells. Seroconversion against SPE-L and SPE-M was observed in healthy blood donors, suggesting that the toxins are expressed in vivo. Interestingly, the speL gene is highly associated with S. pyogenes M89, a serotype that is linked to acute rheumatic fever in New Zealand.

Amino Acid Sequence↗
PubMed1989

Evaluation of the Rapid Strep system for identification of gram-positive, catalase-negative cocci isolated from bovine intramammary infections.

The Rapid Strep system (Analytab Products, Plainview, NY) was used to identify 199 gram-positive, catalase-negative cocci isolated from bovine intramammary infections. The system accurately identified 88.4% of isolates. The system identified 100% of 46 Streptococcus agalactiae, 100% of 48 Streptococcus dysgalactiae, 54.5% of 11 Streptococcus equinus, and 96.2% of 53 Streptococcus uberis isolates. Enterococcus spp. were identified correctly 83.3% of the time. One of 4 Streptococcus saccharolyticus strains was identified as Streptococcus bovis, the previous classification for this organism, and 8 Streptococcus equi ssp. equi strains were misidentified as Streptococcus dysgalactiae. The Rapid Strep system was determined to be an acceptable alternative to conventional methods for identification of gram-positive, catalase-negative cocci isolated from bovine intramammary infections.

Animals↗
PubMed2000

Septic orchitis in an alpaca.

An adult, intact male alpaca was presented with an acute onset of unilateral scrotal swelling. Following complete physical and ultrasonographic examination, the most likely differential diagnoses were orchitis, hematoma, and testicular torsion. The animal was castrated and histopathologic evaluation revealed unilateral orchitis. Streptococcus equi subsp. zooepidemicus was cultured.

Animals↗
PubMed1998

Zoocin A immunity factor: a femA-like gene found in a group C streptococcus.

A 6.8-kb fragment of Streptococcus equi subsp. zooepidemicus 4881 DNA containing the zoocin A gene (zooA) was cloned in Escherichia coli and sequenced. We have identified a gene we call zoocin A immunity factor (zif), which protects the producer cell from the otherwise lethal action of its own product. Transformation of Streptococcus gordonii DL1 with zooA and zif changed its phenotypic character from a non-zoocin A producing-zoocin A sensitive cell to a zoocin A producing-zoocin A resistant cell. zif has sequence homology to femA (factor essential for methicillin resistance) and lif (lysostaphin immunity factor). No differences were observed in amino acid or amino sugar compositions of peptidoglycan purified from zoocin A sensitive vs. zoocin A immune cells.

Amino Acids↗
PubMed2006

Getting a grip on strangles: recent progress towards improved diagnostics and vaccines.

'Strangles', caused by infection with the bacterium Streptococcus equi, remains one of the most commonly diagnosed and important infectious diseases of horses world-wide. This review discusses the diagnosis and pathogenesis of strangles with particular attention to the significance of persistent infections in disease transmission and the rapid progress now being made towards the development of effective preventative vaccines. It is now possible combine recent sequence data from the N-terminal region of the SeM protein and reassign the SeM alleles using the on-line database http://pubmlst.org/szooepidemicus/seM/. Hypotheses concerning the origin of this variation and the potential for its exploitation for the epidemiological analysis of outbreaks are proposed. Advances in understanding of the molecular evolution of S. equi highlight the role played by phage-mediated acquisition of virulence factors and suggest new avenues for prophylactic intervention.

Animals↗
PubMed1994

Genetic structure of populations of beta-haemolytic Lancefield group C streptococci from horses and their association with disease.

The genetic structure of beta-haemolytic Lancefield group C streptococci isolated from horses in Australia was examined by multilocus enzyme electrophoresis. The 249 isolates comprised 70 classified phenotypically as Streptococcus equi subspecies equi, 177 classified as S equi subspecies zooepidemicus and two which were unclassifiable. Forty-one electrophoretic types were identified which could be classified into three major clusters, A, B and C. Of the isolates, 178 fell into cluster B (types 4 to 22) and lay within a genetic distance of 0.36. Sixty-nine of the 70 S equi subspecies equi isolates fell into type 12, which suggests that they were members of a single clone, and the isolates from abscesses were significantly more likely to belong to type 12 than those from horses with no clinical signs (P < 0.001). There were no other significant associations between electrophoretic types or clusters and the isolation of the organism from particular sites. These data suggested that S zooepidemicus may be the archetypal species from which the clone designated subspecies equi has been derived. If isolates of the subspecies equi from other geographical regions also prove to be members of electrophoretic type 12, this hypothesis would be strengthened.

Animals↗
PubMed2001

Streptococcal meningitis resulting from contact with an infected horse.

We report a case of group C streptococcal meningitis in a woman with a history of close animal contact as well as head trauma as a result of a kick by a horse. Blood and cerebrospinal fluid cultures grew Streptococcus equi subsp. zooepidemicus, as did a throat culture taken from the colt that had kicked her 2 weeks prior to admission.

Animals↗
PubMed2003

Purpura haemorrhagica in 53 horses.

The medical records of 53 horses with purpura haemorrhagica were reviewed. Seventeen of them had been exposed to or infected with Streptococcus equi, nine had been infected with Corynebacterium pseudotuberculosis, five had been vaccinated with S. equi M protein, five had had a respiratory infection of unknown aetiology, and two had open wounds; the other 15 cases had no history of recent viral or bacterial infection. The horses were between six months and 19 years of age (mean 8.4 years). The predominant clinical signs were well demarcated subcutaneous oedema of all four limbs and haemorrhages on the visible mucous membranes; other signs included depression, anorexia, fever, tachycardia, tachypnoea, reluctance to move, drainage from lymph nodes, exudation of serum from the skin, colic, epistaxis and weight loss. Haematological and biochemical abnormalities commonly detected were anaemia, neutrophilia, hyperproteinaemia, hyperfibrinogenaemia, hyperglobulinaemia and high activities of muscle enzymes. All of the horses were treated with corticosteroids; 42 also received non-steroidal anti-inflammatory drugs and 26 received antimicrobial drugs. Selected cases received special nursing care, including hydrotherapy and bandaging of the limbs. Most of the horses were treated for more than seven days and none of them relapsed. Forty-nine of the horses survived, one died and three were euthanased, either because their severe clinical disease failed to respond to treatment or because they developed secondary complications. Two of the four non-survivors had been vaccinated against S. equi with a product containing the M protein, one had a S. equi infection and the other had a respiratory infection of undetermined aetiology.

Adrenal Cortex Hormones↗
PubMed2004

Characterization of group C and G streptococcal strains that cause streptococcal toxic shock syndrome.

Twelve strains (the largest number ever reported) of group C and G(1) streptococci (GCS and GGS, respectively) that caused streptococcal toxic shock syndrome (STSS) were collected and characterized. Eleven strains were identified as Streptococcus dysgalactiae subsp. equisimilis, and one strain was identified as Streptococcus equi subsp. zooepidemicus. We found that it was the first reported case of STSS caused by S. equi subsp. zooepidemicus. Cluster analysis according to the 16S rRNA gene (rDNA) sequences revealed that the S. dysgalactiae strains belonged to clusters I and II, both of which were closely related. The emm types and the restriction patterns of chromosomal DNA measured by pulsed-field gel electrophoresis were highly variable in these strains except BL2719 and N1434. The 16S rDNA sequences and other characteristics of these two strains were indistinguishable, suggesting the clonal dissemination of this particular S. dysgalactiae strain in Japan. As the involvement of superantigens in the pathogenesis of group A streptococcus-related STSS has been suggested, we tried to detect known streptococcal superantigens in GCS and GGS strains. However, only the spegg gene was detected in seven S. dysgalactiae strains, with none of the other superantigen genes being detected in any of the strains. However, the sagA gene was detected in all of the strains except Tokyo1291. In the present study no apparent factor(s) responsible for the pathogenesis of STSS was identified, although close genetic relationships of GCS and GGS strains involved in this disease were suggested.

Antigens, Bacterial↗
PubMed1995

Equine strangles modelled in mice.

Small animal models of Streptococcus equi infection have been confined to parenteral injection of mice which subsequently develop a septicaemia. To devise a model of infection more closely resembling strangles, 4.9 x 10(6) cfu of S. equi were placed on the nares of C3H and Balb/c mice (fifteen of each). Compared with ten uninfected controls, infected mice sneezed more often and their daily weight gain was significantly reduced. Histopathological examination seven days after infection revealed varying degrees of nasopharyngeal and regional lymphoid pathology in twenty two mice. Eleven mice had an early or mild rhinitis in which the nasal epithelium presented microabscesses containing polymorphonuclear leucocytes. Another eleven mice had a suppurative rhinitis or pharyngitis associated in most with regional lymphadenitis; in two mice, abscessated lymph nodes had erupted into perinodal connective tissues. Two mice had a vestibular abscess. The suppurative rhinitis was associated with extensive necrosis of nasal propria which occasionally extended to conchal bone, resulting in osteomyelitis. Multiple bacterial abscesses were seen in the spleen of one mouse. Histological lesions were not detected in control mice or in eight infected mice. S. equi was re-isolated from the nares of fourteen of the twenty two affected mice but not from the eight unaffected challenged mice or control mice. The close resemblance of this model to strangles in horses may justify its further use for the investigation of pathogenesis and protective immunity.

Animals↗
PubMed1997

Characterization of the Lancefield group C streptococcus 16S-23S RNA gene intergenic spacer and its potential for identification and sub-specific typing.

The 16S-23S RNA gene intergenic spacers of isolates of Streptococcus equi (n = 5), S. zooepidemicus (n = 5), S. equisimilis (n = 3) and S. dysgalactiae (n = 2) were sequenced and compared. There were distinct regions within the spacer, arranged in the order 1-9 for all S. equi and one S. zooepidemicus isolate and 1,2 and 4-9 for the remaining isolates. Region 4 was identical to the tRNA(ala) gene found in the 16S-23S intergenic spacers of other streptococci. Regions 1, 5, 6 and 7 had distinct variations, each conserved in different isolates. However, amongst the intergenic spacers there were different combinations of variant regions, suggesting a role for DNA recombination in their evolution. The intergenic spacer of all isolates of S. equi and one S. zooepidemicus isolate were almost identical. Primers derived from the variant sequences of regions 1 and 5 to 6 were used to group all S. zooepidemicus (n = 17) and S. equi (n = 5) into 1 of 8 types by polymerase chain reaction; three S. zooepidemicus isolates typed the same as S. equi. S. equi and S. zooepidemicus were clearly distinguishable from S. equisimilis and S. dysgalactiae which had shorter regions 5 and 6 and no region 7. Most homology for the group C sequences was found in previously published sequences for the 16S-23S intergenic spacers of S. anginosis, S. constellatus, S. intermedius, S. salivarius and S. agalactiae. A 75-90 nucleotide length shared with S. anginosus and S. intermedius in opposite orientations in the two main variants of region 6 supported the role for DNA recombination in the evolution of the spacer. The 16S-23S intergenic spacers indicate that S. zooepidemicus was the archetypal species for S. equi and that both are genetically more distant from S. equisimilis and S. dysgalactiae. The intergenic spacer can be used to identify specifically the group C streptococci and as an epidemiological marker for S. zooepidemicus.

Animals↗
PubMed1995

Pathology of equine respiratory disease occurring in association with transport.

Eight young thoroughbred horses, taken 1858 km by road (travelling time, 41 h), were examined to assess the pathological nature of respiratory disease associated with transport. Three of the horses showed clinical abnormalities including pyrexia, coughing, leucocytosis and neutrophilia after the first 20 h of transportation. Endoscopical examination of the trachea revealed exacerbation of airway inflammation as a result of transport in two of the three affected horses. A consistent finding in the affected horses was focal serous neutrophilic pneumonia affecting the cranio-ventral portion of the caudal lung lobe with a propensity to affect the right lung. Streptococcus equi subspecies zooepidemicus was isolated from the pneumonic areas, in which corresponding bacterial antigens were identified immunohistochemically. Viral cultures from the pneumonic lesions proved negative for respiratory viruses. It is suggested that transport predisposes the upper respiratory tract and the lower airways to invasion by the bacterium, with episodic pyrexia and acute pneumonia.

Acute Disease↗
PubMed2006

Standing surgical removal of inspissated guttural pouch exudate (chondroids) in ten horses.

OBJECTIVE: To report use of a modified Whitehouse approach in standing horses for management of inspissated guttural pouch empyema. STUDY DESIGN: Retrospective study. ANIMALS: Adult horses (n=10) with guttural pouch empyema. METHODS: Inspissated exudate in 1 or both guttural pouches was removed surgically through a modified Whitehouse approach, with the horses standing and sedated. Medical records of affected horses were reviewed to determine history; physical, endoscopic, and radiological examination findings; surgical technique; complications, and outcome. RESULTS: All horses had purulent nasal discharge; 3 horses had dysphagia, 2 had recurrent laryngeal neuropathy on the side affected by guttural pouch empyema, and 1 had persistent soft palate displacement. Inspissated exudate was removed safely without causing apparent discomfort. Eight horses returned to their previous level of athletic activity after surgery; 1 horse dysphagic before surgery, was euthanatized because of persistent dysphagia after surgery, and 1 horse died 1 week after surgery for unknown reasons. Streptococcus equi subsp equi was isolated from the affected guttural pouch of 3 horses. CONCLUSIONS: Inspissated exudate can be removed surgically from the guttural pouch in standing horses through a modified Whitehouse approach. CLINICAL RELEVANCE: To eliminate risks associated with general anesthesia and avoid surgical suite contamination, removal of chondroids can be performed in standing sedated horses through a modified Whitehouse approach.

Animals↗
PubMed2000

Endoscopic and bacteriological findings in a chronic outbreak of strangles.

Recently there has been increased awareness of the role of the carrier state in propagating Streptococcus equi var equi (S equi) infections (strangles), although the anatomical location of the organisms in chronic carriers has not been consistently established. This case report describes a chronic strangles outbreak in a riding school, that was monitored over six months by repeated clinical and endoscopic guttural pouch examinations. All asymptomatic horses that had positive S equi cultures on nasal swabs or guttural pouch lavages were found to have lesions in their guttural pouches. These lesions included empyema, chondroids and previously undescribed chronic discharging lesions on the floor of the medical compartment of the guttural pouches. These observations further support previous studies indicating the importance of investigating the guttural pouches in horses suspected to be asymptomatic carriers of this organism.

Animals↗
PubMed2003

Expression of the genes for lysostaphin and lysostaphin resistance in streptococci.

To determine if the genes for lysostaphin endopeptidase (end) and lysostaphin resistance (epr) function in streptococci, we transferred these genes from Staphylococcus simulans biovar staphylolyticus into two strains of Streptococcus equi subsp. zooepidemicus. The end-containing streptococci were able to produce and process proendopeptidase. Strains containing epr were more resistant to lysis by the streptococcolytic enzyme zoocin A and amino acid analysis of the peptidoglycans of the epr-containing streptococci revealed insertion of serines in their cross bridges. This is the first report of the transfer of a femABX-like immunity factor resulting in a physiologically useful effect in a different genus.

Bacterial Proteins↗
PubMed2006

AgdbNet - antigen sequence database software for bacterial typing.

BACKGROUND: Bacterial typing schemes based on the sequences of genes encoding surface antigens require databases that provide a uniform, curated, and widely accepted nomenclature of the variants identified. Due to the differences in typing schemes, imposed by the diversity of genes targeted, creating these databases has typically required the writing of one-off code to link the database to a web interface. Here we describe agdbNet, widely applicable web database software that facilitates simultaneous BLAST querying of multiple loci using either nucleotide or peptide sequences. RESULTS: Databases are described by XML files that are parsed by a Perl CGI script. Each database can have any number of loci, which may be defined by nucleotide and/or peptide sequences. The software is currently in use on at least five public databases for the typing of Neisseria meningitidis, Campylobacter jejuni and Streptococcus equi and can be set up to query internal isolate tables or suitably-configured external isolate databases, such as those used for multilocus sequence typing. The style of the resulting website can be fully configured by modifying stylesheets and through the use of customised header and footer files that surround the output of the script. CONCLUSION: The software provides a rapid means of setting up customised Internet antigen sequence databases. The flexible configuration options enable typing schemes with differing requirements to be accommodated.

Algorithms↗