Royce W. Waltrip

Borna disease virus and schizophrenia

The development of a new serological assay method to detect antibodies in human sera recognizing Borna disease virus (BDV) proteins and a clinical pilot study are presented. Psychiatric patients from a schizophrenia research clinic in Baltimore, Maryland, were examined for antibodies to BDV antigen with traditional indirect immunofluorescence assays (IFA) that used both single and double labeling techniques and also with a Western blot assay capable of detecting antibodies to the three BDV proteins from a human neuroblastoma cell line. Thirteen of 90 (14.4%) patients and 0/20 control subjects had antibodies that recognized more than one BDV protein on the Western blot. Three patients had antibodies that recognized all three BDV proteins. Magnetic resonance imaging assessments of the volume of the putamen (with controls for total cranial volume) differentiated BDV+ from BDV- patients, and there were trend differences for bilateral amygdalae and the left amygdala-hippocampal process. We conclude that: (1) the Western blot assay is superior to IFA assays in BDV serology studies, (2) detection of antibodies to more than one BDV protein is a useful working criterion for seropositivity, (3) the 14.5 kDa BDV protein is 10 times more predictive of seropositivity than either the 38/40 kDa or the 24 kDa protein, (4) there is tentative evidence for a schizophrenia-control difference in the prevalence of anti-BDV antibodies, and (5) it is likely that there are neuroanatomical/behavioral features that differentiate seropositive from seronegative schizophrenic patients.

The Effect of Clozapine on Plasma Norepinephrine: Relationship to Clinical Efficacy

Clozapine is an atypical neuroleptic medication with superior efficacy to conventional antipsychotic agents for patients with chronic, symptomatic schizophrenia. Neurochemical characteristics that distinguish clozapine from other neuroleptics and contribute to its differential efficacy are not known. We assessed the effects of clozapine on plasma levels of norepinephrine (NE) in a double-blind, parallel groups comparison of clozapine (n = 11) and haloperidol (n = 15) in chronic schizophrenic outpatients who had been previously treated with fluphenazine. Simultaneous measurements were obtained for plasma levels of the catecholamine precursor dopa, the dopamine metabolite dihydroxyphenylacetic acid (DOPAC), the NE metabolite 3,4-dihydroxyphenylglycol (DHPG), adrenocorticotropin (ACTH), Cortisol, and hemodynamic parameters. Clozapine produced marked increases (471%) in plasma NE levels, whereas haloperidol had no significant effects on plasma NE levels. Clozapine also increased dopa and tended to increase DOPAC levels, without effects on DHPG, ACTH, or Cortisol levels and without consistent changes in blood pressure. Across patients, the magnitude of clozapine-induced increments in plasma NE levels was positively related to improvement in positive symptoms and global symptomatology and was unrelated to the occurrence of extrapyramidal symptoms. The results suggest that clozapine differs importantly from other neuroleptics in increasing plasma NE levels, with the peripheral noradrenergic stimulation related to its superior efficacy profile. The unchanged DHPG levels and absence of hypertension suggest a more complex mechanism of action of clozapine than heightened NE release alone.

Borna disease virus antibodies and the deficit syndrome of schizophrenia

We detected anti-Borna disease virus (BDV) antibodies at a 14.4% rate in patients with schizophrenia. The hypothesis of a higher rate of BDV seropositivity in deficit syndrome was borne out in a subset of 64 patients categorized according to the Schedule for the Deficit Syndrome with 5/15 seropositive deficit and 4/49 seropositive nondeficit (p < 0.05). This suggests that the antibodies and possibly a BDV-like virus are pathogenetically linked to this form of schizophrenia.

Clinical, Serologic, and Histopathologic Characterization of Experimental Borna Disease in Ponies

Borna disease was originally described as an equine neurologic syndrome over 200 years ago, although the infectious etiology of the disorder was unproven until the early 20th century. Borna disease virus (BDV) was finally isolated from horses dying of the disorder, and that virus has been used to experimentally reproduce Borna disease in several species of laboratory animals. However, BDV has never been inoculated back into horses to experimentally and etiologically confirm the classic clinical, pathologic, and serologic characteristics of the disease in that species. Three ponies were intracerebrally inoculated with different amounts of BDV and were evaluated clinically, serologically, and neurohistopathologically. All 3 animals developed the clinical signs characteristically described for naturally occurring Borna disease, including ataxia, torticollis, postural unawareness, rhythmic repetitive motor activities, muscle fasciculation, and cutaneous hyperesthesia and hypoesthesia over several body surfaces. Two ponies died after rapid onset of these signs 28–30 days postinoculation. The third animal made a nearly complete clinical recovery. Seroconversion occurred only after the onset of signs and to a marked degree only in the convalescent animal. Virus was recovered postmortem from 2 of the 3 ponies, and a BDV-specific nucleic acid sequence was detectable in all 3 animals using a reverse transcription-polymerase chain reaction procedure. Gross neural lesions were absent, but histopathologically there was generalized intense mononuclear perivascular cuffing, glial nodule formation, and astrocytosis in all 3 brains. Confirming a diagnosis of Borna disease is difficult and perhaps best accomplished using a combination of the clinical, serologic, and histopathologic indicators of this unusual disease supported by positive reverse transcription-polymerase chain reaction findings.

IMMUNOPATHOLOGY AND VIRAL REACTIVATION : A GENERAL THEORY OF SCHIZOPHRENIA

A theory is proposed that explains a broad range of clinical manifestations in schizophrenia. It is a heuristic device for organizing research in the neuroimmunology and virology of schizophrenia. This approach is different from other immune and viral theories of schizophrenia and defines testable hypotheses for further theory refinement or rejection. Defective alpha-interferon (alFN) regulation resulting in excessive effect is postulated to cause schizophrenia. The role of alFN in the regulation of development and its induction within the brain by the reactivation of viruses that are commonly present in the normal central nervous system (CNS) are the primary pathophysiological mechanisms. Biological properties of alFN include neural excitation, opiate and adrenocorticotropic hormone activity, and inhibition of cellular proliferation and differentiation. Psychosis results from in situ viral stimulation of alFN production in the CNS of a vulnerable host having defective regulation of either sensitivity or production. Negative symptoms result from alFN effects on CNS development and the behavioral toxicity of alFN. Biological developmental abnormalities, gender differences in severity, and decline in psychotic symptoms with age are discussed in the context of the theory. Research strategies and specific testable hypotheses are presented.

Diazepam treatment of early symptoms of schizophrenic relapse.

In an open trial, nine drug-free schizophrenic patients received oral diazepam, 10 to 40 mg/day, for the treatment of early symptoms of relapse. Diazepam treatment led to a return of the patients usual condition in seven of 11 episodes.

Synthetic peptide-based electrochemiluminescence immunoassay for anti-Borna disease virus p40 and p24 antibodies in rat and horse serum

Borna disease virus (BDV) is a neurotropic pathogen that infects a wide variety of vertebrates. We have developed a new electrochemiluminescence immunoassay (ECLIA) for the detection of antibodies to BDV, using three synthetic peptides corresponding to the amino acid residues 3-20 and 338-358 of p40 and 59-79 of p24 peptide of BDV. Using the ECLIA, we examined serum samples for the presence of anti-BDV antibodies in 20 rats (experimentally BDV-infected and uninfected) and 38 horses (13 US horses, experimentally infected and uninfected, and 25 Japanese horses, feral and domestic). The ECLIA, performed in a double-blind manner, detected anti-BDV antibodies in rats with a history of BDV infection, giving results that were in agreement with indirect immunofluorescence assay and/or Western blot (WB) analysis. The ECLIA also correctly identified all three experimentally infected horses and four domestic American horses that were seropositive for BDV antibodies by WB. Among the Japanese horses, at least two out of 10 feral and six out of 15 domestic horses were seropositive for BDV. In most of these cases, the specificity of immunoreactivity was verified by blocking with soluble p40 and p24 peptides.

A Virus-Associated Immunopathological Theory of Schizophrenia

Schizophrenia is a clinical syndrome which is increasingly considered to be a neurological disease with behavioral symptoms that primarily manifest as dysfunction of frontal and limbic brain areas. Hypotheses of the etiology or etiologies of schizophrenia have tended to be limited to intrinsic central nervous system (CNS) processes, such as neurotransmitter dysregulation or neuroanatomical models. These models have a correspondingly limited predictive validity. An alternate and potentially more useful perspective of the disease would be one that takes into account its pleomorphic nature. Schizophrenia has a broad spectrum of associated findings suggesting involvement of developmental processes and a pathophysiology that may be systemic in nature. Viral hypotheses have been one way that the issue of pleomorphism has been addressed.

Rating affective flattening from videotaped interviews

Semistructured interviews with 28 schizophrenic patients were videotaped. The affective flattening section of the Scale for the Assessment of Negative Symptoms (SANS) was rated after each interview. At a later date, each videotape was rated by three raters as well as the interviewer. Reliability was estimated within and across rating conditions by intraclass correlation. Comparison of reliability scores across rating conditions indicated that the videotape medium had little effect on the ability of raters to rate affective flattening similarly.