Autoimmunity against dopamine receptors in neuropsychiatric and movement disorders: a review of Sydenham chorea and beyond.

Antineuronal autoantibodies are associated with the involuntary movement disorder Sydenham chorea (SC) and paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) which are characterized by the acute onset of tics and/or obsessive compulsive disorder (OCD). In SC and PANDAS, autoantibodies signal human neuronal cells and activate calcium calmodulin-dependent protein kinase II (CaMKII). Animal models immunized with group A streptococcal antigens demonstrate autoantibodies against dopamine receptors and concomitantly altered behaviours. Human monoclonal antibodies (mAbs) derived from SC target and signal the dopamine D2L (long) receptor (D2R). Antibodies against D2R were elevated over normal levels in SC and acute-onset PANDAS with small choreiform movements, but were not elevated over normal levels in PANDAS-like chronic tics and OCD. The expression of human SC-derived anti-D2R autoantibody V gene in B cells and serum of transgenic mice demonstrated that the human autoantibody targets dopaminergic neurones in the basal ganglia and other types of neurones in the cortex. Here, we review current evidence supporting the hypothesis that antineuronal antibodies, specifically against dopamine receptors, follow streptococcal exposures and may target dopamine receptors and alter central dopamine pathways leading to movement and neuropsychiatric disorders.

Canine distemper epizootic in Everglades mink.

Four free-ranging mink, Neovison vison, collected between June and September 2004 in the Fakahatchee Strand Preserve State Park (FSPSP, Florida, USA), were examined for canine distemper virus (CDV) infection. Microscopic lesions and viral inclusions consistent with CDV infection were observed in three mink. Virus isolation and reverse transcription-polymerase chain reaction performed on all mink were positive for CDV. Anecdotal records of mink observations in FSPSP suggest a postepizootic decline in the mink population followed by an apparent recovery. We recommend further research to assess the status of the Everglades mink and the impact of CDV on this and other American mink populations in Florida.

Overlapping humoral autoimmunity links rheumatic fever and the antiphospholipid syndrome.

OBJECTIVE: Rheumatic fever (RF) and the antiphospholipid syndrome (APS) are autoimmune diseases that share similar cardiac and neurological pathologies. We assessed the presence of shared epitopes between M protein, N-acetyl-beta-D-glucosamine (GlcNAc) and beta2 glycoprotein-I (beta2GPI), the pathogenic molecules engaged in these autoimmune conditions. METHODS: Sera from the APS patients were affinity-purified on beta2GPI and beta2GPI-related peptide columns. Sera from RF patients were affinity-purified on protein G column. The beta2GPI and M protein-related peptides were prepared by conventional solid-phase peptide synthesis. The enzyme-linked immunosorbent assay direct binding and inhibition studies were performed on the RF and APS sera for the presence, and cross-reactivity, of antibodies against beta2GPI, beta2GPI-related peptides, streptococcal M protein, M-derived peptides and GlcNAc. RESULTS: Antibodies (Abs) to beta2GPI were found in 24.4% of 90 RF patients. Antibodies against various beta2GPI-related peptides were found in 1.1-36.7% of the patients. The immunoglobulin G sera from RF patients possessed significant anti-beta2GPI activity, while sera from APS patients contained a considerable anti-streptococcal M protein as well as anti-GlcNAc activity. Furthermore, affinity-purified anti-beta2GPI and anti-beta2GPI-related peptide Abs from APS patients cross-reacted with streptococcal M protein and M5 peptide, while beta2GPI and beta2GPI-related peptides inhibited anti-streptococcal M protein activity from RF patients. The results were confirmed by immunoblot analyses. The beta2GPI also inhibited anti-GlcNAc activity from APS patients with chorea. CONCLUSIONS: The results of our study, showing a considerable overlap of humoral immunity in RF and APS, support a hypothesis that common pathogenic mechanisms underlie the development of cardiac valve lesions and Central Nervous System abnormalities in both diseases.

The implantable cardioverter-defibrillator: postcode prescribing in the UK 1998-2002.

OBJECTIVE: To determine the rate of implantable cardioverter-defibrillator (ICD) implantation across the UK during the period 1998 to 2002. DESIGN: Observational self reporting with cross checking. SETTING: All ICD implanting centres coordinated by the National Pacemaker and ICD Database. PATIENTS: Every patient receiving an ICD in the UK from 1998 to 2002. MAIN OUTCOME MEASURES: Date of implantation and postcode of each ICD recipient during the study period. RESULTS: ICD implantation increased in the UK in the five year period studied but fell far short of the European average and national targets. Implantation rates varied greatly by region. CONCLUSIONS: The low rate of ICD implantation in the UK and the disparity between regions require further study to determine the barriers to this evidence based treatment.

Prevalence of sarcocysts in Florida black bears (Ursus americanus floridanus).

Sections of muscle from Florida black bears (Ursus americanus floridanus) collected in the state of Florida were observed for the presence of Sarcocystis sp. sarcocysts. Two of 132 (1.5%) black bears had muscle sections containing sarcocysts. One sarcocyst was observed per muscle section. The sarcocysts averaged 181.5 x 99.0 microm by light microscopy of hematoxylin and eosin-stained sections.

Trombiculiasis in the Florida black bear.

We found trombiculid mite (Trombiculidae) infestations in 32 of 101 (32%) freeranging Florida black bears (Ursus americanus floridanus) live-captured or necropsied in Florida from January 1999 to April 2000. Prevalence of chigger infestation was greatest in June with no infestations seen October to March. Chigger infestations were recognized as accumulations of bright orange granular material usually associated with hair shafts. Mites were found in clusters of one to 102 (mean +/- SD = 8.5+/-19.5) and were distributed primarily over the ventral abdomen and thorax, inguinal and axillary regions, and proximal medial aspect of the extremities. Mites were identified as larval Eutrombicula splendens. Cutaneous lesions were seen in two of 32 (6%) infested bears.

Induction of autoimmune valvular heart disease by recombinant streptococcal m protein.

Rheumatic heart disease is an autoimmune sequela of group A streptococcal infection. Previous studies have established that streptococcal M protein is structurally and immunologically similar to cardiac myosin, a well-known mediator of inflammatory heart disease. In this study, we investigated the hypothesis that streptococcal M protein could produce inflammatory valvular heart lesions similar to those seen in rheumatic fever (RF). Fifty percent (3 of 6) of Lewis rats immunized with recombinant type 6 streptococcal M protein (rM6) developed valvulitis as well as focal lesions of myocarditis. Valvular lesions initiated at the valve surface endothelium spread into the valve. Anitschkow cells and verruca-like lesions were present. T cells from rM6-immunized rats proliferated in the presence of purified cardiac myosin, but not skeletal myosin. A T-cell line produced from rM6-treated rats proliferated in the presence of cardiac myosin and rM6 protein. The study demonstrates that the Lewis rat is a model of valvular heart disease and that streptococcal M protein can induce an autoimmune cell-mediated immune attack on the heart valve in an animal model. The data support the hypothesis that a bacterial antigen can break immune tolerance in vivo, an important concept in autoimmunity.

Pathogenic mechanisms in rheumatic carditis: focus on valvular endothelium.

To clarify immune-mediated mechanisms in rheumatic heart disease caused by group A streptococcal infection, valve tissues from rheumatic patients with valvular heart disease who required valve replacement were studied for reactivity with monoclonal anti-CD4 or anti-CD8 monoclonal antibodies or anti-vascular cell adhesion molecule-1 (VCAM-1). At the valve surface, CD4(+) and CD8(+) T lymphocytes were adherent to valve endothelium and penetrated through the subendothelial layer. T cell extravasation into the valve through the surface valvular endothelium appeared to be an important event in the development of rheumatic heart disease. VCAM-1 was expressed on the valvular endothelium in rheumatic valves. Evidence suggested that the pathogenesis of rheumatic heart disease involved the activation of surface valvular endothelium with the expression of VCAM-1 and the extravasation of CD4(+) and CD8(+) lymphocytes through the activated endothelium into the valve. Lymphocytic infiltration through the valve surface endothelium has not been appreciated as a potential initiating step in disease pathogenesis.

Reactivity of rheumatic fever and scarlet fever patients' sera with group A streptococcal M protein, cardiac myosin, and cardiac tropomyosin: a retrospective study.

Archived sera (collected in 1946) from acute rheumatic fever (ARF) and untreated scarlet fever and/or pharyngitis patients were reacted with streptococcal M protein, cardiac myosin, and cardiac tropomyosin. Except for very low levels to tropomyosin, antibodies to other antigens were not elevated in the sera of ARF patients relative to those of non-ARF patients, even though there was roughly equivalent exposure to group A streptococci. This suggests that antibodies to these molecules may not play a central role in the induction of ARF.

T-Cell-dependent antibody response to the dominant epitope of streptococcal polysaccharide, N-acetyl-glucosamine, is cross-reactive with cardiac myosin.

Autoantibodies against myosin are associated with myocarditis and rheumatic heart disease. In this study, the antigenic cross-reactivity of myosin and N-acetyl-glucosamine (GlcNAc), the dominant epitope of Group A streptococcal polysaccharide, was examined. Six antimyosin monoclonal antibodies (MAbs) derived from mice with cardiac myosin-induced myocarditis were characterized. All MAbs cross-reacted with GlcNAc, mimicking a subset of MAbs derived from rheumatic carditis patients that bind both myosin and streptococcal polysaccharide. Variable (V) region gene usage was diverse, with five of six MAb heavy-chain V regions encoded by distinct members of the J558 family and the sixth encoded by a member of the VGAM3.8 family. Light-chain V-region segments were derived from the Vk1, Vk4/5, Vk10, and Vk21 families. These antimyosin, anti-GlcNac MAbs demonstrated several T-cell-dependent features: they were predominantly immunoglobulin G, were encoded by V-region genes expressed late in development, and displayed somatic mutation. A direct correlation between the extent of somatic mutation and the affinity for myosin was observed. Affinity for GlcNAc also increased with the frequency of mutation, demonstrating that affinity maturation can occur simultaneously for both self antigen and foreign antigen. Based on these observations, we immunized mice with GlcNAc coupled to bovine serum albumin and demonstrated that a T-cell-dependent response to GlcNAc leads to antimyosin reactivity. We speculate that the pathogenic antibody response in rheumatic carditis may reflect the conversion of a T-cell-independent response to GlcNAc to a T-cell-dependent cross-reactive response to GlcNAc and myosin.

Pathogenesis of group A streptococcal infections.

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.

Cytotoxic mAb from rheumatic carditis recognizes heart valves and laminin.

Anti-streptococcal antibodies cross-reactive with N-acetyl-betaD-glucosamine (GlcNAc) and myosin are present in the sera of patients with rheumatic fever (RF). However, their role in tissue injury is not clear. In this study, we show that anti-GlcNAc/anti-myosin mAb 3.B6 from a rheumatic carditis patient was cytotoxic for human endothelial cell lines and reacted with human valvular endothelium and underlying basement membrane. Reactivity of mAb 3.B6 with the valve was inhibited by human cardiac myosin > laminin > GlcNAc. The mAb 3.B6 epitopes were localized in fragments of human cardiac myosin, including heavy meromyosin (HMM), the S1 subfragment, and two light meromyosin (LMM) peptides containing amino acid sequences KEALISSLTRGKLTYTQQ (LMM 1) and SERVQLLHSQNTSLINQK (LMM 33). A novel feature of mAb 3.B6 was its reactivity with the extracellular matrix protein laminin, which may explain its reactivity with the valve surface. A laminin A-chain peptide (HTQNT) that includes homology to LMM33 inhibited the reactivity of mAb 3.B6 with human valve. These data support the hypothesis that cross-reactive antibodies in rheumatic carditis cause injury at the endothelium and underlying matrix of the valve.

Molecular analysis of cross-reactive anti-myosin/anti-streptococcal mouse monoclonal antibodies.

Nucleotide sequences of VH- and VL-genes of anti-myosin/anti-streptococcal monoclonal antibodies (mAbs) were analyzed and compared with their highly detailed antigen binding reactivities. Antigen-specificities of the cross-reactive mAbs included myosin, streptococcal M-protein, actin, keratin, N-acetyl-beta-D-glucosamine, vimentin, DNA, tropomyosin, troponin, and laminin as previously described. After nucleotide sequence analysis, homology indicated that some of the V gene sequences aligned with antibodies recognizing gangliosides and blood group antigens glycophorin M and N. Therefore, mAb reactivity with gangliosides and glycophorin M and N was identified. The cross-reactive mAbs utilized a heterogeneous group of germline V-heavy genes comprised of nine J558-, four 7183- and two Q52-family VH-genes. Germline V-light genes utilized by the mAbs included six Vkappa4/5-, three Vkappa8-, two Vkappa10-, three Vkappa19- and one Vkappa23-family VL-genes. No preferential VH/VL-chains correlated with any of the 12 different antigen reactivities, even for mAbs with nearly identical cross-reactivities. However, we did find that the cross-reactive mAb germline genes within a V gene family shared more homology among themselves than with other germline genes within their V gene families, suggesting convergent mutation. Cross-reactive mAbs with the highest relative avidity for myosin were found in the VH7183 family which contained two cytotoxic mAbs. Antibodies with V gene sequences most homologous to those of our cross-reactive anti-myosin/anti-streptococcal mAbs had specificities for laminin, DNA, carbohydrates, or blood group antigens and were reported to cause autoimmune disease in mice.

Vacuum-assisted closure versus saline-moistened gauze in the healing of postoperative diabetic foot wounds.

Diabetic foot wounds present a great challenge to wound care practitioners. The objective of this pilot study was to determine whether vacuum-assisted closure (V.A.C.) therapy would afford quicker wound resolution as compared to saline-moistened gauze in the treatment of postoperative diabetic foot wounds. Ten patients were randomized into either the experimental V.A.C. group or control saline gauze group. Included in the study were diabetic patients 18 to 75 years of age who had a nonhealing foot ulceration. Excluded were those patients with venous disease, coagulopathy, or those who had active infections not resolved by initial surgical debridement. All foot ulcers were surgically debrided prior to initiation of V.A.C. or gauze treatment. In the experimental group, V.A.C. dressings were applied in accordance with manufacturer's protocol for chronic wounds and changed every 48 hours. In the control group, saline gauze dressings were applied at the time of surgical debridement and changed twice a day thereafter. Measurements and photos were obtained to document wound progress. Main outcome measures included: 1) time to satisfactory healing (calculated from date of initial debridement to date of definitive closure, and 2) change in wound surface area (calculated from initial wound tracing to final tracing). Satisfactory healing in the V.A.C. group was achieved in 22.8 (+/- 17.4) days, compared to 42.8 (+/- 32.5) days in the control group. Surface area changes of 28.4% (+/- 24.3) average decrease in wound size in the V.A.C. group, compared to a 9.5% (+/- 16.9) average increase in the control group during measurement period.

Atrial septal defects in Florida panthers.

Ostium secundum atrial septal defects (ASDs) were observed in six (3 M, 3 F) of 33 (20 M, 13 F) (18%) Florida panthers (Puma concolor coryi) necropsied by veterinary pathologists between 1985 and 1998. A seventh ASD was found in a female panther necropsied in the field and is included in the pathological description but not the prevalence of ASDs in Florida panthers. One panther (FP205) with severe ASD also had tricuspid valve dysplasia (TVD). Atrial septal defects and/or TVD are believed to have caused or contributed to the deaths of three (9%) Florida panthers in this study. Mean diameter +/- SD of ASDs was 9.0 +/- 4.7 mm (range 3 to 15 mm). Gross pathological changes attributed to ASDs/TVD in severely affected panthers (ASD > or = 10 mm) (n = 4) included mild right ventricular dilatation (n = 3) and hypertrophy (n = 2), mild to severe right atrial dilatation (n = 2), and acute pulmonary edema (n = 3). Panthers with mild ASDs (ASD < or = 5 mm) (n = 3) had no other detectable gross pathological changes associated with the ASDs. Histological examination of lungs of three panthers with severe ASDs revealed mild to moderate dilatation with fibrosis and smooth muscle atrophy of the tunica media of medium to large caliber arteries (n = 2), interstitial and/or pleural fibrosis (n = 2), perivascular fibrosis (n = 1), and acute to chronic edema (n = 3). Twenty-six necropsied panthers were examined one or more times while living; medical records were retrospectively evaluated. Antemortem radiographic, electrocardiographic, and echocardiographic examinations were performed on two panthers with severe ASDs (FP20 and FP205). Thoracic radiographic abnormalities in both included right heart enlargement, and in FP205 (severe ASD and TVD), mild pulmonary overperfusion. Electrocardiographic examination of FP205 revealed a right ventricular hypertrophy pattern, while FP205 had a normal electrocardiogram. Echocardiographic examination of FP20 revealed marked right atrial dilatation; a bubble contrast study indicated regurgitation across the tricuspid valve. Echocardiographic abnormalities in FP20 included right atrial and ventricular lilatation, atrial septal drop-out, and severe tricuspid regurgitation; non-selective angiography revealed significant left to right shunting across the ASD. All panthers with severe ASDs ausculted (n = 3) had systolic right or left-sided grade I-V/VI murmurs loudest at the heart base. All male panthers with ASDs (n = 3) (100%) and 9 of 17 (53%) male panthers without ASDs in this study were cryptorchid.

Anti-human cardiac myosin autoantibodies in Kawasaki syndrome.

Kawasaki syndrome (KS) is the major cause of acquired heart disease in children. Although acute myocarditis is observed in most patients with KS, its pathogenesis is unknown. Because antimyosin autoantibodies are present in autoimmune myocarditis and rheumatic carditis, the purpose of the current study was to determine whether anticardiac myosin Abs might be present during the acute stage of KS. Sera from KS patients as well as age-matched febrile controls and normal adults were compared for reactivity with human cardiac myosin in ELISAs and Western blot assays. A total of 5 of 13 KS sera, as compared with 5 of 8 acute rheumatic fever sera, contained Ab titers to human cardiac myosin that were significantly higher than those found in control sera. Both cardiac and skeletal myosins were recognized in the ELISA by KS sera, although stronger reactivity was observed to human cardiac myosin. Only IgM antimyosin Abs from KS sera were significantly elevated relative to control sera. KS sera containing antimyosin Abs recognized synthetic peptides from the light meromyosin region of the human cardiac myosin molecule and had a different pattern of reactivity than acute rheumatic fever sera, further supporting the association of antimyosin Ab with KS. These Abs may contribute to the pathogenesis of acute myocarditis found in patients with KS.

Vitamin A concentrations in serum and liver from Florida panthers.

Many of the anomalies and clinical signs afflicting the Florida panther (Felis concolor coryi) are suggestive of vitamin A deficiency. Our objectives in this study were to determine if a vitamin A deficiency exists in the free-ranging panther population and to determine if there are differences in vitamin A levels among various subgroups of free-ranging panthers. Retinol concentrations were used as an index to Vitamin A concentrations and were determined in serum and liver from free-ranging (serum, n = 45; liver, n = 22) and captive (serum, n = 9; liver, n = 2) juvenile and adult Florida panthers from southern peninsular Florida (USA), and in liver from free-ranging cougars (F. concolor subspp.) from Washington (USA) and Texas (USA) between November 1984 and March 1994. Combined juvenile (6- to 24-mo-old) and adult (> 24-mo-old) free-ranging Florida panthers had mean +/- SD serum retinol concentrations of 772.5 +/- 229 pmol/ml. Adult free-ranging Florida panthers had mean liver retinol concentrations of 4794.5 +/- 3747 nmol/g. Free-ranging nursing Florida panther kittens (age < 1 mo) had mean serum retinol concentrations of 397.9 +/- 69 pmol/ml. Among subgroups of free-ranging Florida panthers, females had higher corrected mean serum retinol concentrations than males and adult free-ranging Florida panthers had higher mean liver retinol concentrations than juveniles. Retinol concentrations in free-ranging Florida panthers did not differ significantly from those in captive panthers (liver and serum) or other free-ranging cougars (liver). Based on limited published values and our controls, a vitamin A deficiency could not be demonstrated in the Florida panther population nor were any subgroups or individuals considered deficient.

Haemophilus influenzae type b polysaccharides-protein conjugate vaccine elicits a more diverse antibody repertoire in infants than in adults.

Conjugation of bacterial polysaccharides (PS) to protein carriers confers the ability to elicit protective serum Ab in infants, who respond poorly to plain PS. The serum Ab of young children immunized with Haemophilus influenzae type b (Hib) PS conjugate vaccine varies with age and Ag formulation. To understand these age-related changes in human anti-Hib PS immune responses we determined the variable region gene sequences encoding anti-Hib PS mAbs of infants immunized with Hib oligosaccharide-diphtheria toxin vaccine. The anti-Hib PS repertoire of children differs from that of adults. A smaller proportion of mAbs from children have high affinity for Hib PS, and the overall variable region gene repertoire of infants is more diverse than that in adults. Variable region genes encoding high affinity mAbs of infants are similar to the restricted repertoire described in adults. Low affinity anti-Hib PS mAbs of infants are encoded by a heterogeneous group of genes that are uncommonly observed in the adult repertoire. Abs with high affinity for Hib PS from infants, like most mAbs from adults, react only with Hib PS and the structurally similar PS of Escherichia coli K100, whereas low affinity mAbs of infants are polyreactive. The low affinity anti-Hib PS mAbs of infants immunized with Hib oligosaccharide-diphtheria toxin vaccine vaccine are not reflected in serum Ab. However, the differences between the variable region gene repertoires of adults and infants may account for the distinct immunologic characteristics of the anti-Hib PS responses in young children immunized with other vaccine formulations.