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Vertigo, or the symptom of an hallucination of motion, is usually caused by disorders of the inner ear. Buried in the bone of the otic capsule, the inner ear is the most difficult human sensory organ to image and investigate. As an inner ear disorder, Meniere’s disease (MD) is characterised as recurrent vertiginous attacks, fluctuating hearing loss which can be progressive, tinnitus and aural fullness. Post-mortem studies, and now MRI inner ear imaging, show an excess of endolymph or endolymphatic hydrops (ELH) which has been assumed to usually commence in the cochlea. However, the cause of the initial hydrops is still debated. This paper reflects on the research published in Ōtautahi Christchurch, Aotearoa New Zealand. There is evidence from post-mortem studies, electrophysiological test, and some inner ear imaging that endolymphatic obstruction from clumps of detached saccular otoconia may be a cause of MD. [ABSTRACT FROM AUTHOR]

Background: The Royal Australasian College of Surgeons (RACS) aims to achieve Māori health equity and cultural safety within the surgical workforce. The RACS Māori Health Strategy and Action Plans encourage Surgical Education and Training (SET) selection criteria that recognizes and credit applicants who identify as Māori or demonstrate competence in Māori health issues. This study investigates the current SET selection criteria for Māori entering surgical specialties. Methods: The selection criteria for each surgical speciality for the proposed 2024 intake were examined through a documentary analysis. Criteria were reviewed for applicability to Māori identification and/or cultural competency. Results: Criteria related to Māori identification and/or cultural competency make up 6%, 2%, and 1.5% of Otolaryngology and Head and Neck, General, and Vascular Surgery total SET selection score respectively. Criteria related to Māori identification and/or cultural competency make up 9% and 0.1% of Orthopaedic and Plastics and Reconstructive Surgery ranking scores for interview eligibility respectively. Cardiothoracic Surgery, Paediatric Surgery, Neurosurgery and Urology specialties do not incorporate any criteria appertaining to Māori. Allocation of research‐related points determined by authorship may disincentivize Māori trainees. Conclusions: Some surgical specialties fail to recognize or credit Māori identification and cultural competency in SET selection criteria. There is a need for regular auditing to ensure SET criteria align with the RACS aspirations for Māori health equity and cultural safety within the surgical workforce. [ABSTRACT FROM AUTHOR]

A 60-year-old man with asymmetrical sensorineural hearing loss and tinnitus was found to have bilateral lipomata in the mastoid bone. The patient had a history of noise exposure through his agricultural occupation. The lipomata were identified through magnetic resonance imaging (MRI) and computed tomography (CT) scans. Lipomas were confirmed through fat suppression techniques on MRI. Surgery is generally not necessary for intraosseous lipomas, as they are typically benign and slow-growing tumors. This case highlights the importance of considering lipoma as a possible diagnosis for mastoid bone masses and the use of fat suppression techniques for confirmation. [Extracted from the article]

Cochlear implantation (CI) surgery is a highly effective procedure for severe to profound hearing loss, with a low complication rate. There are currently multiple grading systems for CI surgery complications, making comparison of outcomes difficult. We propose a modification to the Clavien-Dindo classification of complications, and use this modified classification to analyse our complications. Complications were classified as: I – Self-limiting complications requiring no treatment or simple pharmacological therapies; II – Complications requiring pharmacological interventions other than those permitted under the criteria for Grade I, or non-invasive radiological imaging; IIIa – Complications necessitating surgical, radiological or endoscopic intervention, but excluding implant explantation and/or reimplantation. IIIb – Complications necessitating implant explantation and/or reimplantation. 1053 patients were recorded as having had at least one cochlear implant inserted with 114 complications reported in 90 patients. The 114 complications were classified into the proposed classification with 18 (15.7%) as Grade I, 36 (31.5%) as Grade II, 17 (14.9%) as Grade IIIa and 43 (34.2%) as Grade IIIb. We found a low complication rate, and were able to use the modified Clavien-Dindo classification system to analyse our data. We would strongly advocate for a uniform reporting system and propose this modification of a widely used system. [ABSTRACT FROM AUTHOR]

Iodine has been shown to act as a good electrocatalyst for metal digestion in deep eutectic solvents (DESs) but little is known about its speciation or reactivity in these high chloride containing media. Extended X-ray absorption fine structure (EXAFS) spectroscopy measurements were made at the iodine K-edge in a range of DESs with different glycolic or acidic hydrogen bond donors (HBDs), along with examining the effect of iodine concentration between 0.01 and 0.5 mol dm−3. Three groups of speciation were detected: mixed I2Cl−/I3− (glycol and lactic acid systems), mixed I3−/I2 (oxalic acid and urea systems), and singular I3− (levulinic acid system). UV-vis spectroscopy was used to confirm the speciation. Electrochemistry showed that iodine redox behaviour was unaffected by the changing speciation. Leaching data showed that metal oxidation was related not only to changing iodine speciation, but also the reactivity and coordination ability of the HBD. [ABSTRACT FROM AUTHOR]

Pneumonia has been reported in both free-ranging and captive koalas and a number of causative agents have been described. Between 2016 and 2019, 16 free-ranging and 1 captive koala (Phascolarctos cinereus) from the Mount Lofty Ranges of South Australia were identified with pyogranulomatous lobar pneumonia, which involved the left caudal lobe in 14/17 (82%) cases. Within lesions, numerous gram-positive or gram-variable, non-acid-fast filamentous bacteria were observed in association with Splendore-Hoeppli phenomenon. Culture yielded growth of anaerobic bacteria, which were unidentifiable by MALDI-TOF-MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry) analysis in 5/5 cases. Sequencing of the bacterial 16S rRNA gene identified a novel Actinomyces species in 4 samples, confirming a diagnosis of pulmonary actinomycosis. Concurrent examination of resin lung casts from healthy koalas suggested greater laminar flow of air to the left caudal lung lobe in koalas. Actinomyces spp. have been reported as commensals of the oral microbiome in other species, and an association with similar pulmonary lesions in other species. Considering the predilection for involvement of the left caudal lung lobe, aspiration is suggested as the likely cause in some cases of pulmonary actinomycosis in koalas. Pulmonary actinomycosis has not been previously described in koalas and further work needs to be undertaken in order to classify this organism within the Actinomyces genus. [ABSTRACT FROM AUTHOR]

Aim: This systematic review evaluates the current evidence for the use of probiotics in the prevention of acute otitis media (AOM) in children. Methods: This study is registered with PROSPERO prior to commencement. PubMed, MEDLINE, EMBASE and Cochrane database were searched using relating keywords. All literature was screened to determine relatability to the topic. Review articles were also screened for additional literature. Results: Thirteen studies were found on probiotics and their role in preventing AOM in children. They ranged in quality from poor to moderate. Half (2/4) of the studies that used nasal probiotic formulations showed a significant difference in reducing otitis media, while only a third (3/9) of the studies using oral formulations suggest benefit in reducing AOM. None of the studies demonstrated significant adverse effects from probiotics. Conclusion: The evidence for any effect of probiotics on the prevention of AOM is limited, and the overall low quality of studies makes it difficult to draw definitive conclusions. No serious adverse events were noted, and there is some evidence to suggest possible benefit with nasal probiotic administration. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study is to observe the education and vocational achievements and social participation of cochlear implant recipients as they graduate from a paediatric cochlear implant programme and identify any significant associations that might exist.Method: This study identified 56 patients from the Southern Cochlear Implant Programme (SCIP) who received cochlear implants before the age of 19 (paediatric) and are now over the age of 19 (adult). A questionnaire investigated their education, employment, and identity with the hearing and deaf communities. Also included were the satisfaction with life scale and Hearing Participation Scale (HPS). Subjects ranged in age from 19 to 32.Results: Twenty-six patients responded to the questionnaire, including one non-user. Twenty identified strongly or very strongly with the hearing community. There was weak evidence of a linear association between strong identity with the hearing community and a higher HPS score. No other statistically significant associations were detected. Interestingly, 12 out of 26 participants found employment through family.Conclusion: Positive outcome trends in education and employment were seen in this study although no statistical significance was achieved. There is a strong bias for those who use their cochlear implants regularly, and there are no data available for those who do not use their cochlear implants for comparison as only one non-user completed the survey, despite efforts to include this group. This study shows that there is perceived benefit in implantation for patients who use it regularly but further research is needed with a more diverse group of cochlear implant recipients. [ABSTRACT FROM AUTHOR]

Introduction: The drug treatment of autism spectrum disorders is often poorly tolerated and has traditionally targeted associated conditions (such as inattention or irritability) that frequently coexist, with limited benefit for the core social deficits. Here, I describe the novel use of a low dose of the anti-epileptic phenytoin to enhance social functioning in a patient with an autism spectrum disorder. Case presentation: I present the case of a 19-year-old Caucasian man with autism spectrum disorder treated with stimulant medication since early childhood. He experienced long-standing difficulties in establishing and maintaining relationships and reading social cues, and was socially isolated. Within 10 minutes of a single sublingual low dose of phenytoin there was an immediate observable improvement in his eye contact and integration of both verbal and non-verbal communication. This enhanced social functioning associated with his adherence to the low-dose phenytoin therapy was maintained for over 18 months of follow-up. These clinical observations were supported by ratings using the Autism-Spectrum Quotient and the Depression, Anxiety and Stress Scales, recorded pre-treatment and after seven months on 5mg phenytoin. Conclusion: This case report provides the first potential evidence that a low dose of phenytoin, a widely used and well tolerated anti-epileptic medication, may be capable of modifying the core social cognitive deficits associated with autism spectrum disorders. While acknowledging this is a single case study, the lack of availability of safe and effective treatments to address the important core deficits associated with autism spectrum disorders makes this case noteworthy. [ABSTRACT FROM AUTHOR]

Computed tomography (CT) of the temporal bones confirmed a non-specific soft tissue mass centred on the mesotympanum with extension into the Eustachian tube consistent with glomus tympanicum (Fig. Repeat MRI 5 years post-surgery showed no further middle ear lesion but an extensive multi-compartmental lesion extending from the skull base to the left parapharyngeal space. [Extracted from the article]

Objectives To determine the pattern of auditory responses, time-course of hearing deterioration, and possible site of lesion following retrosigmoid excision of unilateral vestibular schwannomas. Design Prospective, nonrandomized, observational pilot study. Setting Tertiary referral medical center. Main outcome measures Preoperative and postoperative pure-tone and speech audiometry, auditory brainstem response testing, and distortion product otoacoustic emissions were performed in 20 patients. Testing was conducted every 24 hours for the duration of hospitalization. Transtympanic electrocochleography was performed if delayed deterioration of auditory responses was documented. Results Of the 20 patients, 7 had no discernible cochlear nerve at the end of the procedure. Of the 13 patients with an intact nerve, 6 retained hearing, 3 with evidence of reduced neural function. Of the 7 who lost hearing despite an intact nerve, 5 lost at least cochlear and possibly also neural function, and 1 had reduced neural function but retained cochlear function. There were two examples of delayed deterioration of cochlear nerve responses. Conclusions Hearing loss following retrosigmoid removal of vestibular schwannomas most often involves loss of at least cochlear function, possibly in addition to neural damage. In a smaller number of cases anacusis or hearing deterioration can be attributed to purely neural trauma. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to determine if cochlear implantation (CI) improved speech discrimination in the New Zealand pedigree with the A7445G mitochondrial DNA (mtDNA) mutation and sensorineural hearing loss (SNHL). METHODS: Nine patients had their speech discrimination and pure tone audiograms evaluated. Pre- and post-implant results were compared. Type of CI and patient age at implantation was recorded. RESULTS: Speech discrimination testing shows greatly improved functional hearing after CI in this group of patients. DISCUSSION: Individuals with mtDNA-related SNHL should be identified by screening and offered assessment for CI suitability because functional hearing improves after CI. [ABSTRACT FROM AUTHOR]

The koala is one of Australia's most highly specialized folivores with a diet exclusively of eucalyptus leaves to provide all nutritive needs and therefore requires to be free of oral disease as they are dependent on good dentition for optimal health and quality of life. We developed an oral examination methodology based on protocols for companion animals and human dentistry to chart the oral health of koalas. Thirty free-ranging koalas from South-East Queensland, Australia were examined for general body and oral health. Inspection of the oral cavity was conducted for the presence or absence of the indicators of oral disease such as caries or periodontal disease. Univariate and multivariate analyses were performed on the examination data and a prototype oral health chart developed. The prototype was then trialled and the methodology validated by the Kappa statistic using ten additional koalas examined by four multidisciplinary personnel involved in koala care. Trauma associated fractures, tooth displacement, abnormal occlusion and tooth wear, compacted vegetation, extrinsic stain deposits, periodontal bone loss, gingivitis, tooth mobility, and calculus were present in the oral cavities of the examined koalas. A system of scoring between 0 and 3 was constructed in accordance with current koala general health charting formats. Validation of the charting method using Kappa coefficients of agreement statistics indicated that there was a good agreement among observers on recorded results except for inflammation and calculus scoring. Modifications were made and visual aids and index scales produced to further assist observers. Oral health surveillance has been proven in other species to be significant in diagnosing physiological disturbances derived from environmental, genetic, and developmental causes. Veterinarians, dental researchers, and koala husbandry personnel will benefit in using this charting method and reporting the oral health of koala populations in their future findings. This unique form of oral health monitoring would be adaptable to other mammals. [ABSTRACT FROM AUTHOR]

Ménière's disease is an inner ear disorder characterized by vertigo attacks, fluctuating and progressive hearing loss, tinnitus, and aural fullness in the affected ear. The pathophysiology of Ménière's disease remains elusive. Theories so far are anatomical variation in the size or position of the endolymphatic sac and duct, viral inflammation or autoimmune involvement of the sac, or a genetically determined abnormality of endolymph control. Animal studies on blocking the ductus reuniens and endolymphatic duct have produced hydrops in the cochlea, saccule, and utricle. Cone beam computed tomography images show a similar pattern with apparent obstruction of the ductus reuniens, saccular duct, and endolymphatic sinus. New studies documenting the age of onset of Ménière's disease show a pattern similar to benign paroxysmal positional vertigo, raising the possibility that the fundamental cause of Ménière's disease might be detached saccular otoconia. [ABSTRACT FROM AUTHOR]

Introduction: CHARGE syndrome is a rare congenital condition that manifests with anomalies of coloboma, heart defects, choanal atresia, mental retardation, genitourinary and ear anomalies that can affect almost any part of the auditory pathway. In those patients with a significant sensorineural hearing loss, cochlear implantation has become a potential therapeutic option. Methods: Chart review of three cases from the Southern Cochlear Implant Programme. Outcomes: All patients met clinical diagnostic criteria of CHARGE syndrome, and had abnormal inner ear anatomy with profound sensorineural hearing loss. One child had previously undergone cochlear implantation which was unsuccessful due to increasing non-auditory stimulation. All patients had successful cochlear implantation with full insertion of a Nucleus Freedom Implant with contour Advance. All patients showed improvement in their audiological function; one child has high functioning verbal communication, one child uses both sign and verbal communication with improved speech quality and ability to speech read, and one child responds reliably to sound, understands short phrases and attempts to vocalize, but this is limited by tracheostomy. Conclusion: Cochlear implantation faces numerous challenges in children with CHARGE syndrome, but with appropriate patient selection can result in successful audiologic and quality of life outcomes. [ABSTRACT FROM AUTHOR]

Background: We previously reported an increased rate of progression of periodontal disease over an 18-month period in human immunodeficiency virus (HIV)-positive subjects compared to controls. The mechanism for disease progression and rapid tissue loss was unknown. Data on the microbiological studies tailed to show any significant difference in the microbial characteristics of the periodontal lesions in HIV-positive patients compared to HIV-negative controls. Immunological analysis had identified neutrophils as an important component of the host defense against periodontal infection, especially against rapid tissue loss. Serum IgG reactivities to periodontal pathogens in HIV-positive patients with periodontitis were reduced. Other data provided circumstantial evidence to suggest that IgG subclass (IgG2) specific antibody might assist bacterial clearing in periodontal infection. The aim of the current study was to examine the specific IgG subclass antibody response to a panel of periodontopathic organisms: Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn), Campylobacter rectus (Cr), and Bacteroides forsythus (Bf) in HIV-positive patients compared to HIV-negative controls. Methods: Sera from 120 HIV-positive patients (40 periodontitis, 69 gingivitis, and 11 no oral diseases) were tested for IgG subclass specific antibody response to the above listed 6 organisms using enzyme-linked immunosorbent assay. Data were compared with those obtained from 40 HIV-negative control subjects (35 periodontitis, 2 gingivitis, and 3 no oral diseases). Results: In the HIV-positive group, a consistently high response rate was found in IgG1 to ail the bacteria tested, in addition, high levels of IgG3 and IgG4 to Pg and IgG1 and IgG2 to Pi were also present. However, no significant difference was detected among the periodontitis, gingivitis, and no oral disease subgroups. When the periodontitis patients from the HIV-positive group were compared to the HIV-negative group, no difference in the antibody levels and response rates was noted. Conclusion: We conclude that in HIV-positive patients, the specific IgG subclass antibody response to periodontopathic organisms was similar to that of HIV-negative subjects. [ABSTRACT FROM AUTHOR]

Background: It has previously been suggested that CD4+ T cells play a pivotal role in regulating the immune response to periodontal pathogens. The aim of the present study therefore was to determine delayed type hypersensitivity (DTH), spleen cell proliferation, serum and splenic anti-Porphyromanas gingivalis antibody levels, and lesion sizes following challenge with viable P. gingivalis in CD4-depleted BALB/c mice immunized with P. gingivalis outer membrane proteins (OMP). Methods: Four groups of BALB/c mice were used. Groups 1 and 2 were injected intraperitoneally (ip) with saline for 3 consecutive days and then weekly throughout the experiment. Groups 3 and 4 were injected ip with rat immunoglobulin and a monoclonal rat anti-mouse CD4 antibody, respectively. Two days later, group 1 mice were injected ip with saline only, while all the other groups were immunized ip with P. gingivalis OMP weekly for 3 weeks. One week later following the last immunization of OMP, 3 separate experiments were conducted to determine: 1) the DTH response to P. gingivalis OMP by measuring footpad swelling: 2) the levels of antibodies to P. gingivalis in serum samples and spleen cell cultures using an enzyme-linked immunosorbent assay, as well as spleen cell proliferation after stimulation with OMP: and 3) the lesion sizes after a sub-cutaneous challenge with viable P. gingivalis cells. Results: In CD4+ T-cell-depleted mice (group 4), the DTH response and antigen-stimulated cell proliferation were significantly suppressed when compared to groups 2 and 3. Similarly, the levels of serum and splenic IgM, IgG, and all IgG subclass antibodies to P. gingivalis OMP were depressed. Delayed healing of P. gingivalis-induced lesions was also observed in the CD4+ T-cell-depleted group. Conclusions: This study has shown that depletion of CD4+ T cells prior to immunization with P. gingivalis OMP led to the suppression of both the humoral and cell-mediated immune response to this microorganism and that this was associated with delayed healing. These results suggest that the induction of the immune response to P. gingivalis is a CD4+ T-cell-dependent mechanism and that CD4+ T cells are important in the heating process. [ABSTRACT FROM AUTHOR]

Background: Susceptibility to pariodontal infections may, in part, be genetically determined. Porphyromonas gingivalis is a major periodontopathogen, and the immune response to this organism requires T-cell help. The aim of the present study was to examine the specific T-cell cytokine responses to P. gingivalis outer membrane antigens in a mouse model and their relationship with H-2 haplotype. Methods: BALB/c and DBA/2J (H-2d), CBACaH (H-2k), and C57BL6 (H-2b) mice were immunized with P. gingivalis outer membrane antigens weekly for 3 weeks. One week after the final injection, the spleens were removed, and 6 T-cell lines specific for P. gingivalis mere established for each mouse strain. The percentage of CD4 and CD8 cells in the P. gingivalis -specific T-cell lines staining positive for intracytoplasmic interleukin (IL)-4, interferon (IFN)-γ, and IL-10 was determined by 2-color flow cytometry. Results: The cytokine profiles of T-cell lines from BALB/c and DBA/2J mice showed no significant differences. Significantly fewer IL-4+, IFN-γ+, and IL-10+ CD4 cells than IL-4+, IFN-γ+, and IL-10+ CD8 cells, respectively, were demonstrated for both strains. P. gingivalis-specific T-cell lines generated from CBACaH mice were similar to those generated from BALB/c and DBA/2J mice; however, the mean percentage of IL-4+ CD4 cells in CBACaH mice was lower than the percentage of IFN-γ+ CD4 cells. Also, the mean percentage of IFN-γ+ CD4 cells in CBACaH mice was significantly increased compared to DBA/2J mice. Unlike the other 3 strains, T-cell lines established from C57BL6 mice contained similar percentages of cytokine-positive cells, although the percentage of IL-4+ CD4 tells was reduced in comparison to the percentage of CD8 cells. However, comparisons with the other 3 strains demonstrated a higher percentage of IL-4+ CD4 cells than in lines established from the spleens of DBA/2J mice, IFN-γ+ CD4 cells then in lines established from BALB/c and CBACaH mice, and IL-10+ CD4 cells than in lines established from all 3 other strains. No significant differences in the percentage of positive CD8 cells were demonstrated between lines in the 4 strains of mice. Conclusion: The specific T-cell response to P. gingivalis in mice may, in the case of the CD4 response, depend on MHC genes. These findings are consistent with the concept that patient susceptibility is important to the outcome of periodontal infection and may, in part, be genetically determined. [ABSTRACT FROM AUTHOR]

A wide range of animals suffer from periodontal disease. However, there is very little reported on disease and oral micro-biota of Australian animals. Therefore, the oral cavity of 90 marsupials was examined for oral health status. Plaque samples were collected from the subgingival margins using curettes or swabs. Plaque samples were plated onto non-selective trypticase soy agar plates, selective trypticase soy agar, non-selective and selective Wilkens Chalgrens Agar. Plates were incubated in an anaerobic atmosphere and examined after 7–14 days for the presence of black–brown-pigmented colonies. A combination of morphological and biochemical tests were used (colonial morphology, pigmentation, aerobic growth, Gram reaction, fluorescence under long-wave UV light (360 nm), production of catalase, enzymatic activity with fluorogenic substrates and haemagglutination of sheep red cells) to identify these organisms. Black-pigmented bacteria were cultivated from the plaque of 32 animals including six eastern grey kangaroos, a musky rat kangaroo, a whiptail and a red-necked wallaby, 18 koalas, a bandicoot and five brushtail possums. No black-pigmented colonies were cultivated from squirrel or sugar gliders or quokkas or from marsupial mice. The majority of isolates were identified as Porphyromonas gingivalis -like species with the higher prevalence of isolation from the oral cavity of macropods (the kangaroos and wallabies). Oral diseases, such as gingivitis can be found in native Australian animals with older koalas having an increase in disease indicators and black-pigmented bacteria. Non-selective Wilkens Chalgren Agar was the medium of choice for the isolation of black-pigmented bacteria. [Copyright &y& Elsevier]

Background: The immune response to Porphyromonss gingivalis in the mouse abscess model is known to be dependent upon CD4 T-cell activation and the regulatory role of cytokines. The role of interleukin-10 (IL-10) in this mouse model was examined in vivo. Methods: One-week-old, female BALB/c mice were divided into 4 groups. Groups 1 and 2 were given intra peritoneal (ip) injections of phosphate buffered saline (PBS) weekly for 5 weeks. Group 3 was given an ip injection of rat immunoglobulin. Group 4 was injected with rat anti-1L-10 antibodies. At week 6, group 1 was sham-immunized with PBS, and groups 2, 3, and 4 were injected with P. gingivalis lipopolysaccharide (Pg-LPS) weekly for 2 weeks. One week after the final immunization, delayed-type hypersensitivity (DTH) was assessed by footpad swelling to Pg-LPS. The level of serum antibodies to Pg-LPS and IFN-gamma (IFN-γ) was determined by enzyme-linked immunosorbent assay. Dorsal abscess formation induced by the injection of viable P. gingivalis was examined daily for 30 days. Results: The footpad swelling of the anti-IL-10-treated group (group 4] was significantly higher than that of groups 1 to 3. Similarly, the serum IFN-γ level in group 4 was much higher than that of the other experimental groups. There was no significant difference in serum IgG antibodies to Pg-LPS in any of the experimental groups. However, the level of IgM antibodies in group A mice was significantly lower than that in groups 2 and 3. In addition, serum IgG1 was suppressed in group 4 mice, while IgG2a antibodies were raised. However, there was no difference observed between the levels of IgG2b and IgG3 antibodies in any group of mice. The lesions in sham-immunized mice (group 1) persisted for 30 days, and those in group 2 and 3 were undetected by day 19 and 20, respectively. In sharp contrast, lesions in group 4 had healed completely by day 13. Conclusions: This study has shown that IL-10 depletion in vivo in P. gingivalis LPS-induced immune response in mice led to an elevated DTH response, an increase in serum IFN-γ levels, and raised levels of IgG and IgG2a antibodies. Treatment with anti-IL-10 antibodies resulted in suppressed IgG1 and IgM responses and a more rapid healing of abscesses than in non-IL-10-depleted mice. These results suggest that IL-10 depletion in Pg-LPS-induced immune response in mice may lead to a Th1-like immune response and provide strong protection against a subsequent challenge with live P. gingivalis in an abscess model. [ABSTRACT FROM AUTHOR]