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Vanda A Lennon

Publications and source records attributed to Vanda A Lennon.

33 records · Page 2Linked to original sources
PubMed2003

Paraneoplastic autoimmune optic neuritis with retinitis defined by CRMP-5-IgG.

Autoantibodies have defined two paraneoplastic visual disorders related to small-cell lung carcinoma: retinopathy ("CAR"-IgG [23kDa, recoverin]) and optic neuritis collapsin response-mediated protein 5 (CRMP-5-IgG [62kDa]). Among 16 patients with CRMP-5-IgG and optic neuritis (aged 52-74 years; all smokers, 9 women), we documented coexisting retinitis in 5. None had CAR-IgG. Fifteen had subacute vision loss, swollen optic discs, and field defects. Vascular leakage was evident at and remote from the disc; 5/5 tested had abnormal electroretinograms. Nine had striking vitreous cells. Vitrectomy showed reactive lymphocytosis (4/4), predominantly CD4(+) (1/1). Most patients had multifocal neurological accompaniments. Cerebrospinal fluid contained lymphocytes (7-32), elevated protein, multiple oligoclonal immunoglobulin bands, and CRMP-5-IgG. Three patients superficially resembled Devic's disease at presentation. One autopsied patient had predominantly CD8(+) T lymphocytes infiltrating optic nerve and spinal cord. Eleven patients had confirmed small-cell carcinoma; 1 had imaging evidence of lung cancer; 3 had renal or thyroid carcinoma. Full-length CRMP-5 protein was identified in normal retina and optic nerve by Western blot analyses. Photoreceptor cells, retinal ganglion cells, and nerve fibers exhibited CRMP-5-specific immunoreactivity. In summary, CRMP-5-IgG defines a paraneoplastic ophthalmological entity of combined optic neuritis and retinitis with vitreous inflammatory cells. Positive serology obviates the need for vitreous biopsy and expedites the search for cancer.

Aged↗
PubMed2003

Metastatic chondroblastoma with elevated creatine kinase and paraneoplastic neurologic autoimmunity.

A 17-year-old girl presented with chondroblastoma of the fibula and pulmonary metastases. Serum creatine kinase (CK) was elevated for a decade preoperatively and fell to near normal after tumor excision. An episode of aseptic meningitis 3 months later led to serologic detection of three antibody markers of paraneoplastic neurologic autoimmunity that in adult patients are characteristic of thymoma and lung carcinoma: muscle-type acetylcholine receptor (AChR) autoantibody (Ab), type 2 Purkinje cell cytoplasmic Ab (PCA-2), and collapsin response-mediator protein-5-IgG (CRMP-5-IgG). Locally recurrent chondroblastoma was excised 1 year later. Serum CK was elevated, CRMP-5-IgG was positive, PCA-2 was lower, and AChR Ab was undetectable. Three years after diagnosis she has stable pulmonary metastases, with elevated CK, higher PCA-2, positive CRMP-5-IgG, and undetectable AChR Ab. The association of metastatic chondroblastoma, elevated CK, and an evolving profile of paraneoplastic autoantibodies reveals a previously unrecognized immunobiologic dimension of chondroblastoma.

Adolescent↗
PubMed2003

Immunization with neuronal nicotinic acetylcholine receptor induces neurological autoimmune disease.

Neuronal nicotinic AChRs (nAChRs) are implicated in the pathogenesis of diverse neurological disorders and in the regulation of small-cell lung carcinoma growth. Twelve subunits have been identified in vertebrates, and mutations of one are recognized in a rare form of human epilepsy. Mice with genetically manipulated neuronal nAChR subunits exhibit behavioral or autonomic phenotypes. Here, we report the first model of an acquired neuronal nAChR disorder and evidence for its pertinence to paraneoplastic neurological autoimmunity. Rabbits immunized once with recombinant alpha3 subunit (residues 1-205) develop profound gastrointestinal hypomotility, dilated pupils with impaired light response, and grossly distended bladders. As in patients with idiopathic and paraneoplastic autoimmune autonomic neuropathy, the severity parallels serum levels of ganglionic nAChR autoantibody. Failure of neurotransmission through abdominal sympathetic ganglia, with retention of neuronal viability, confirms that the disorder is a postsynaptic channelopathy. In addition, we found ganglionic nAChR protein in small-cell carcinoma lines, identifying this cancer as a potential initiator of ganglionic nAChR autoimmunity. The data support our hypothesis that immune responses driven by distinct neuronal nAChR subtypes expressed in small-cell carcinomas account for several lung cancer-related paraneoplastic disorders affecting cholinergic systems, including autoimmune autonomic neuropathy, seizures, dementia, and movement disorders.

Animals↗
PubMed2003

Neuronal ganglionic acetylcholine receptor autoimmunity.

We have developed and validated an assay to detect serum antibodies specific for the ganglionic AChR. The assay uses ganglionic AChR solubilized from membranes of the human neuroblastoma cell line (IMR-32) as antigen. The ganglionic AChR is radiolabeled by complexing with 125I-epibatidine. Among patients with acquired dysautonomia, seropositivity is highly associated with the diagnosis of idiopathic or paraneoplastic autonomic neuropathy and can distinguish these disorders from other forms of autonomic dysfunction. Ganglionic AChR binding antibodies are detectable in 50% of patients with subacute autoimmune autonomic neuropathy (AAN). These patients often have a high antibody value (>0.2 nmol/L). Lower values (0.05-0.20 nmol/L) are found in approximately 10% of patients with limited AAN.

Antibodies↗
PubMed2003

Clinical, magnetic resonance imaging, and electroencephalographic findings in paraneoplastic limbic encephalitis.

OBJECTIVE: To analyze clinical presentation of and paraclinical test abnormalities in patients with paraneoplastic limbic encephalitis (PLE). PATIENTS AND METHODS: We retrospectively reviewed 24 patients seen at the Mayo Clinic in Rochester, Minn, between 1985 and 2002 in whom PLE was suspected. Patients were identified on the basis of clinical history and presence of cancer. Data were reviewed from magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) analysis, electroencephalography (EEG), and paraneoplastic serologic studies. RESULTS: Common manifestations were cognitive dysfunction (92%), seizures (58%), and psychiatric symptoms (50%); 13 patients had small cell lung carcinoma; 11 had other malignancies. Paraneoplastic neuronal autoantibodies were found in 14 (64%) of 22 patients tested. Electroencephalography showed focal or generalized slowing and/or epileptiform activity, maximal in the temporal regions, in all 22 patients tested. Magnetic resonance imaging revealed increased T2 signal involving one or both temporal lobes in 15 (83%) of 18 patients. Cerebrospinal fluid test results were abnormal in 18 (78%) of 23 patients tested. Clinical or radiographic evidence of extralimbic involvement was documented in 12 (55%) of 22 patients. No abnormality on EEG, MRI, or CSF analysis correlated with a specific cancer type or with a specific paraneoplastic autoantibody. CONCLUSIONS: In patients with suspected PLE, EEG is invaluable for confirming cerebral dysfunction. Magnetic resonance imaging can show unequivocal involvement of temporolimbic structures and helps exclude other diagnoses. When EEG and cranial MRI are both normal, PLE is unlikely. Comprehensive testing for paraneoplastic neuronal nuclear, cytoplasmic, and ion channel autoantibodies is an important part of the evaluation, but negative results do not rule out PLE.

Adult↗
PubMed2002

Paraneoplastic neurological autoimmunity associated with ANNA-1 autoantibody and thymoma.

Neurologic autoimmunity frequently occurs with thymoma, particularly myasthenia gravis and skeletal muscle-specific autoantibodies. Type 1 antineuronal nuclear antibody (ANNA-1/"anti-Hu"), which is recognized as an immunoglobulin G marker of small-cell lung carcinoma, has not been reported with thymoma. The authors identified four patients (three under age 40) with ANNA-1 and a paraneoplastic neurologic complication of thymoma. Retrospective testing of stored serum from 172 patients with thymoma revealed ANNA-1 in 3%. This report extends the oncologic implications of ANNA-1 seropositivity.

Adult↗
PubMed2002

Tumor-associated B7-H1 promotes T-cell apoptosis: a potential mechanism of immune evasion.

B7-H1, a recently described member of the B7 family of costimulatory molecules, is thought to be involved in the regulation of cellular and humoral immune responses through the PD-1 receptor on activated T and B cells. We report here that, except for cells of the macrophage lineage, normal human tissues do not express B7-H1. In contrast, B7-H1 is abundant in human carcinomas of lung, ovary and colon and in melanomas. The pro-inflammatory cytokine interferon-gamma upregulates B7-H1 on the surface of tumor cell lines. Cancer cell-associated B7-H1 increases apoptosis of antigen-specific human T-cell clones in vitro, and the apoptotic effect of B7-H1 is mediated largely by one or more receptors other than PD-1. In addition, expression of B7-H1 on mouse P815 tumor increases apoptosis of activated tumor-reactive T cells and promotes the growth of highly immunogenic B7-1(+) tumors in vivo. These findings have implications for the design of T cell-based cancer immunotherapy.

Animals↗
PubMed2002

Paraneoplastic chorea associated with CRMP-5 neuronal antibody and lung carcinoma.

Paraneoplastic chorea is described in 16 patients: 11 with limited small-cell carcinoma, 2 with lung cancer revealed by imaging, 1 with renal cell carcinoma, and 1 with lymphoma. All had CRMP-5-IgG; 6 also had ANNA-1 (anti-Hu), including 1 without evident cancer. Chorea was the initial and most prominent symptom in 11 patients, asymmetric or unilateral in 5 patients, and part of a multifocal syndrome in 14 patients. Basal ganglia abnormalities were revealed by magnetic resonance imaging and at autopsy (as perivascular inflammation and microglial activation). Four patients improved with chemotherapy, and 2 improved with intravenous methylprednisolone.

Aged↗
PubMed2002

Ion channel and striational antibodies define a continuum of autoimmune neuromuscular hyperexcitability.

Neuromuscular hyperexcitability is a characteristic of Isaacs' syndrome. Autoantibodies specific for voltage-gated potassium channels (VGKC) or ganglionic nicotinic acetylcholine receptors (AChR) are markers of this disorder. To determine the frequency of these ion channel antibodies and of related neuron- and muscle-specific antibodies in patients with acquired neuromuscular hyperexcitability, we tested serum specimens from 77 affected patients (35 neuromyotonia, 32 cramp-fasciculation syndrome, 5 rippling muscle syndrome, and 5 focal neuromuscular hyperexcitability) and 85 control subjects. Among study patients, 14% had coexisting myasthenia gravis, and 16% had an associated neoplasm. We found that 35% had VGKC antibodies, 12% ganglionic AChR antibodies, 16% muscle AChR antibodies, and 10% striational antibodies. Overall, 55% had serological evidence of neurological autoimmunity compared to 2% of control subjects. Patients with neuromyotonia were more frequently seropositive (71%) than patients with cramp-fasciculation syndrome (31%). We conclude that acquired neuromuscular hyperexcitability consists of a continuum of clinical disorders with a common autoimmune pathogenesis.

Autoantibodies↗
PubMed2002

ACh receptor protein drives primary and memory autoantibody responses in chimeric human-SCID mice.

The native antigen that drives the T-helper cells regulating production of muscle acetylcholine receptor (AChR) autoantibodies is unknown. Human T cell lines activated by autoantigens in vitro are of unproven relevance to B cell help. Here we report the functional interaction and unprecedented longevity of AChR-specific human T and B lymphocytes residing in SCID mice. Lymphoid cells from myasthenia gravis (MG) patients and healthy subjects were injected ip. Recombinant human AChR-alpha1-subunit-1-210 was injected after day 75. Human AChR-specific Ig was produced rapidly in MG-SCID mice challenged once. Only 1 of 32 control hu-SCID mice produced AChR-specific Ig. This required multiple immunizations, was initially cross-reactive with Torpedo AChR, and had a slow course. Thus, memory T and B lymphocytes specific for human AChR-alpha1-subunit are readily demonstrable in MG patients, interact to produce autoantibody of the same restricted specificity found in the donor's serum, and are long-lived without exogenous autoantigen challenge. In healthy subjects, AChR-specific lymphocytes are infrequent and exhibit naive response characteristics, including apparent affinity maturation of Ig specificity.

Adolescent↗
PubMed2002

Paraneoplastic dysmotility: loss of interstitial cells of Cajal.

Autoimmune impairment and destruction of the enteric nervous plexus are thought to play a central role in the pathogenesis of paraneoplastic motility disorders. We present a case of a small-cell lung carcinoma-related paraneoplastic motility disorder associated with abnormal interstitial cells of Cajal networks. Antibodies against c-Kit and protein gene product 9.5 were used to selectively stain interstitial cells of Cajal and the enteric nervous plexus, respectively. A 68-yr-old man presented with anorexia, early satiety, nausea, and weight loss. Investigations revealed gastroparesis, delayed small intestinal transit, and mediastinal lymphadenopathy. The patient was seropositive for type 1 antineuronal nuclear autoantibody and P/Q-type calcium channel antibody. Biopsy of mediastinal lymph nodes revealed metastatic small-cell carcinoma cells that were immunoreactive for c-Kit. Immunohistochemical staining of a full-thickness small intestinal biopsy revealed a relatively intact myenteric plexus but a sparse and disorganized interstitial cells of Cajal network. The histopathology of this case suggests that interstitial cells of Cajal may be a target in the pathogenesis of paraneoplastic motility disorders.

Aged↗
PubMedDate not supplied

A serum autoantibody marker of neuromyelitis optica: distinction from multiple sclerosis.

BACKGROUND: Neuromyelitis optica is an inflammatory demyelinating disease with generally poor prognosis that selectively targets optic nerves and spinal cord. It is commonly misdiagnosed as multiple sclerosis. Neither disease has a distinguishing biomarker, but optimum treatments differ. The relation of neuromyelitis optica to optic-spinal multiple sclerosis in Asia is uncertain. We assessed the capacity of a putative marker for neuromyelitis optica (NMO-IgG) to distinguish neuromyelitis optica and related disorders from multiple sclerosis. METHODS: Indirect immunofluorescence with a composite substrate of mouse tissues identified a distinctive NMO-IgG staining pattern, which we characterised further by dual immunostaining. We tested masked serum samples from 102 North American patients with neuromyelitis optica or with syndromes that suggest high risk of the disorder, and 12 Japanese patients with optic-spinal multiple sclerosis. Control patients had multiple sclerosis, other myelopathies, optic neuropathies, and miscellaneous disorders. We also established clinical diagnoses for 14 patients incidentally shown to have NMO-IgG among 85000 tested for suspected paraneoplastic autoimmunity. FINDINGS: NMO-IgG outlines CNS microvessels, pia, subpia, and Virchow-Robin space. It partly colocalises with laminin. Sensitivity and specificity were 73% (95% CI 60-86) and 91% (79-100) for neuromyelitis optica and 58% (30-86) and 100% (66-100) for optic-spinal multiple sclerosis. NMO-IgG was detected in half of patients with high-risk syndromes. Of 14 seropositive cases identified incidentally, 12 had neuromyelitis optica or a high-risk syndrome for the disease. INTERPRETATION: NMO-IgG is a specific marker autoantibody of neuromyelitis optica and binds at or near the blood-brain barrier. It distinguishes neuromyelitis optica from multiple sclerosis. Asian optic-spinal multiple sclerosis seems to be the same as neuromyelitis optica.

Adult↗