Clinical Characterization of Definite Autoimmune Limbic Encephalitis: A 30-case Series

Objective Limbic encephalitis (LE) is an inflammatory condition of the limbic system that has an acute or subacute onset. Several types of antibodies are related to the onset of LE, including anti-N-methyl D-aspartate receptor (NMDAR) antibodies and voltage-gated potassium channel (VGKC)-complex antibodies. However, the characteristics and prevalence of LE remain unclear, especially in Asian cohorts, due to the rarity. We aimed to survey their characteristics. Materials and Methods Data of 30 cases clinically defined as "definite autoimmune LE" (based on the standard criteria) were retrospectively collected. These patients were categorized into four subtypes: NMDAR (+) (n=8), VGKC (+) (n=2), antibodies related to paraneoplastic syndrome (n=2), and an antibody-negative group (uncategorized) (n=18). Results LE is rare in Japan, and affected only 30 of 16,759 hospital patients (0.2%) over a ten-year period. The NMDAR (+) group showed distinctive symptoms, while the other three groups had similar indications. Brain MRI indicated significant medial temporal lobe atrophy at one year follow up after discharge. The prevalence of cognitive dysfunction as a complication was 64% (9/14). First-line immunotherapy resulted in a good outcome. A drastic improvement was seen from 4.0±1.1 to 1.1+ on the modified Rankin Scale. A good treatment outcome was observed in all groups (NMDAR, VGKC, and uncategorized), suggesting the importance of an early clinical diagnosis and the early initiation of treatment. Furthermore, we reviewed 26 cases that were clinically diagnosed as definitive autoimmune LE in previous case reports. Conclusion Our findings show that the establishment of a clinical diagnosis based on the clinical criteria of definitive autoimmune LE is important for the initiation of immunotherapy.

Paraneoplastic limbic encephalitis associated with lung cancer

Paraneoplastic limbic encephalitis (PLE) is a rare autoimmune neurological syndrome observed in lung cancer patients. We retrospectively investigated the clinical characteristics, treatment responses, and prognoses in 16 PLE patients who were subsequently diagnosed with lung cancer. Fifteen patients initially presented with disturbance of consciousness, 13 with disorientation, and 12 with seizures. Thirteen patients had autoantibodies, including eight with gamma aminobutyric acid B receptor (GABABR) antibodies and eight with Hu antibodies. PET-CT revealed lung neoplasms in 13 patients, nine of whom exhibited abnormal metabolic activity in the temporal lobe and hippocampus. Fifteen cases were confirmed as limited-stage small cell lung cancer and one as stage IV large cell neuroendocrine carcinoma. Eleven patients received immunomodulatory therapy, and four showed neurological improvement, who all had antibodies against GABABR. Fifteen patients received chemotherapy, of which 14 maintained or improved their PLE status. The overall cancer response rate was 75%, and two-year overall survival was 74.7%. Our results suggest patients with GABAB encephalitis might respond better to immunotherapy than the classical PLE patients with anti-Hu antibodies. Anti-cancer treatment could further improve neurological symptoms. Lung cancer patients with PLE, especially those in limited stage, might have better outcome due to earlier diagnosis and prompt anti-cancer treatment.

Regional susceptibility to TNF-α induction of murine brain inflammation via classical IKK/NF-κB signalling

It is becoming clear that inflammation plays a significant role in a number of neurological and psychiatric conditions. Post mortem brain samples in Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, schizophrenia and most recently autism spectrum condition, all exhibit neuroglial activation and inflammatory markers within the CSF. Many questions remain about the underlying molecular mechanisms. By adding the pro-inflammatory cytokine, TNF-α, to mouse brain tissue we demonstrated that the frontal lobes and temporal region, areas involved in higher functions such as memory and learning, are most susceptible to cytokine-induced inflammation via the NF-κB signalling pathway. We observed direct correlations between the volumetric increase and molecular expression indicating that therapeutic targets in these lobes may require different approaches when treating conditions with a central neuroinflammatory component.

Antibodies to CRMP3-4 associated with limbic encephalitis and thymoma

We present a case with subacute limbic encephalitis (LE) and thymoma. Neither classical onconeural antibodies nor antibodies to voltage gated potassium channels (VGKC) were detected, but the serum was positive for anti-glutamic acid decarboxylase (GAD). The patient serum also stained synaptic boutons of pyramidal cells and nuclei of granule cells of rat hippocampus. The objective of the study was to identify new antibodies associated with LE. Screening a cDNA expression library identified collapsin response mediator protein 3 (CRMP3), a protein involved in neurite outgrowth. The serum also reacted with both CRMP3 and CRMP4 by Western blot. Similar binding pattern of hippocampal granule cells was obtained with the patient serum and rabbit anti-serum against CRMP1-4. The CRMP1-4 antibodies stained neuronal nuclei of a biopsy from the patient's temporal lobe, but CRMP1-4 expression in thymoma could only be detected by immunoblotting. Absorption studies with recombinant GAD failed to abolish the staining of the hippocampal granule cells. Our findings illustrate that CRMP3-4 antibodies can be associated with LE and thymoma. This has previously been associated with CRMP5.

Brain macrophage surface marker expression with HIV-1 infection and drug abuse: a preliminary study

GOAL

To determine the heterogeneity of surface marker expression of macrophages in the temporal lobe of patients who died with AIDS who were also Drug Abusers (DAs). We studied the expression of macrophage surface markers CD11c, CD14, CD68, and HLA-DR and T cell surface markers CD4, and CD8.

BACKGROUND

The macrophage is the prime locus for HIV-1-associated pathology, is the most frequently infected cell in the brain, and has the highest virus load compared to other cells. We previously described the heterogeneity of macrophage surface marker expression and performed morphometric analysis in peripheral nerves of patients who died from AIDS compared to HIV-1 negative individuals. We showed that the HIV-related neuropathy in AIDS is a multifocal process. It is similarly important to determine the expression of macrophage surface markers in brain. Temporal lobe tissue was selected for this preliminary study because we previously found elevated HIV-1 proviral DNA load and inflammatory processes in this neuroanatomic location for subjects who died with AIDS. There is a high prevalence of Drug Abuse in Miami, Florida, associated with AIDS that may interactively affect HIV-associated pathology.

METHODS

Temporal lobe tissue was examined from 17 HIV-1-seropositive patients (4 with Drug Abuse and 13 without Drug Abuse) and 11 HIV-seronegative individuals (5 with Drug Abuse and 6 without Drug Abuse). Standard immunohistochemistry utilized alkaline phosphatase conjugate secondary antibody and fuchsin substrate.

RESULTS

We found that HIV-1 infection and the interaction of HIV-1 infection and Drug Abuse produced changes in macrophage surface marker expression. Macrophage surface markers, CD11c, CD14, CD68, and HLA-DR, and T-cell marker CD4 were increased with statistical significance due to HIV-1 infection (all p < .001) whereas CD8 remained unchanged. Changes due to Drug Abuse alone were not significant. Interaction of Drug Abuse and HIV-infected individuals showed increased expression of CD68 (p = .011), HLA-DR (p = .001), CD4 (p = .027), and CD8 (p = .016).

CONCLUSION

Drug Abuse and HIV-1 infection are factors that differentially and interactively result in multiple macrophages surface marker effects. In HIV-1 infected individuals, Drug Abuse stimulates surface marker expression. Since brain macrophage surface makers do not change uniformly as a result of Drug Abuse and HIV infection, these cells may be heterogeneous and contain sub-types (sub-sets). It remains to be determined which macrophage sub-types may be most pathognomic for pathology.

Increased intrathecal inflammatory activity in frontotemporal dementia: pathophysiological implications

OBJECTIVE

Immunological mechanisms may be part of the pathophysiological mechanisms in frontotemporal dementia (FTD), but hitherto only vague evidence of such mechanisms has been presented. The aim of this study was to compare the cerebrospinal fluid (CSF) levels of the pro-inflammatory cytokines interleukin (IL)-1beta and tumour necrosis factor (TNF)-alpha, and the anti-inflammatory cytokine transforming growth factor (TGF)-beta in patients with FTD and normal controls. Furthermore, serum levels of TNF-alpha, TGF-beta, and IL-1beta were measured in FTD patients.

METHODS

The CSF levels of IL-1beta, TNFalpha, and TGF-beta were measured using ELISA in 19 patients with FTD and 24 sex and age matched healthy controls.

RESULTS

The CSF levels of TNF-alpha (FTD 0.6 pg/mL (median: lower, upper quartile 0.3, 0.7); controls: 0.0 pg/mL (0.0, 0.0); p = 0.008) and TGF-beta (FTD 266 pg/mL (157, 371), controls: 147 pg/mL (119, 156); p = 0.0001) were significantly increased in FTD patients compared with controls. No correlations were found between CSF and serum levels of the cytokines. In the controls, but not in the FTD patients, a positive correlation was found between the CSF levels of TGF-beta and age (r = 0.42, p < 0.05). No correlation was found between any of the cytokines and degree of brain atrophy or white matter changes. No differences between the groups were found for age, gender, or CSF/serum albumin ratio.

CONCLUSIONS

The results suggest an increased intrathecal production of both pro- and anti-inflammatory cytokines in FTD. As no correlations were found with the albumin ratio, and no correlations between CSF and serum levels of the cytokines were found, these changes in the CSF cannot be explained by a systemic overproduction of cytokines.

Complicated paraneoplastic neurological syndromes: a report of two patients with small cell or non-small cell lung cancer

Paraneoplastic neurological syndromes are frequently associated in patients with small cell lung cancer (SCLC) and antineuronal antibodies are involved in the autoimmune mechanism. Multiple syndromes are sometimes complicated in a single patient with SCLC. However, little is known about non-SCLC-associated neurological manifestations. We report two patients with complicated paraneoplastic neurological syndromes. Patient 1 showed paraneoplastic limbic encephalitis (PLE), paraneoplastic sensory neuropathy (PSN) and Lambert-Eaton myasthenic syndrome (LEMS) associated with SCLC. Patient 2 developed opsoclonus-ataxia and probable PLE associated with non-SCLC. Analysis of various antineuronal antibodies revealed that anti-Hu and P/Q-type voltage-gated calcium channel (VGCC) antibodies were positive in Patient 1 but any antibodies were not in Patient 2. Brain MRI demonstrated high intensity signals in temporal lobes particularly on fluid-attenuated inversion recovery (FLAIR) or diffusion-weighted images. These findings suggest that complicated paraneoplastic neurological syndromes occur in non-SCLC as well as SCLC and that unidentified antineuronal autoantibodies may underlie the pathophysiology.

Effects of hemispheric lateralization and site specificity on immune alterations induced by kindled temporal lobe seizures

The effects of kindled seizures elicited from sites in the left and right temporal lobes on mitogen-induced proliferation (LPS, Con A, PHA) and induction of representative TH1 (IFN-gamma) and TH2 (IL-10, IL-4) cytokines were determined in activated rat splenocytes. With reference to cell proliferation, the changes depended on the hemispheric side and location of kindling. Kindling of the left side mediated significant increase in cell proliferation by LPS. Left side kindling resulted in decreased cell proliferation by PHA. Although right side kindling showed no change when taken together, further analysis showed that the reduced proliferation by PHA was mediated when the pyriform cortex was kindled with no change from amygdaloid nuclei. Similar hemispheric polarization was observed in the production of IL-10 and IFN-gamma by Con A-stimulated splenocytes in left side kindled rats. Hence, kindled temporal lobe seizures induced changes in specific immune functions. These effects are not only lateralized but are also specific with respect to the particular region kindled. Since epileptic patients have altered immune functions, this report contributes to our understanding of this complex immune-brain cross-talk in epilepsy.

FasL (CD95L, Apo1L) is expressed in the normal rat and human brain: evidence for the existence of an immunological brain barrier

Despite the mechanical blood-brain barrier, activated T-cells can cross brain vessels. Thus, the CNS is routinely surveyed by immune competent cells; yet the healthy brain is not a target of antigen-specific immune reactions. Therefore, mechanisms must exist to prevent brain-antigen-specific T-cells from inducing immune responses. Data indicate that activated T-cells entering the CNS may undergo apoptosis rather than leaving the brain to induce immune responses. Applying RT-PCR, Western-blots, and immunocytochemistry, we have demonstrated expression of the apoptosis-inducing protein Fas ligand on astrocytes and neurons of apparently normal rat and human brains. FasL-positive astrocytes were often situated in close vicinity to cerebral blood vessels in vivo and induced apoptosis of Fas expressing Jurkat cells in vitro. We propose that similar to other immune privileged organs FasL-induced apoptosis of activated T-cells in the brain protects the tissue from self damaging immune attacks by forming an immunological brain barrier.

The effects of a novel NSAID on chronic neuroinflammation are age dependent

Chronic inflammation may play an important role in the pathogenesis of Alzheimer's disease (AD). The present study compared the effects of chronic neuroinflammation, produced by infusion of lipopolysaccharide (LPS) into the fourth ventricle, upon memory in young, adult, and old rats. Nonsteroidal anti-inflammatory drug (NSAID) therapy may delay the onset of AD. We show that NO-Flurbiprofen (NFP), a novel NSAID that lacks gastrointestinal side effects, attenuated the neuroinflammatory reaction and reduced the inflammation-induced memory deficit. Chronic LPS infusions impaired performance of young rats but not adult or old rats. Treatment with NFP improved the performance of LPS-infused young rats, but not LPS-infused adult or old rats. LPS infusions increased the number of activated microglia in young and adult rats but not old rats. NFP treatment attenuated the effects of LPS upon microglia activation in young and adult rats, but not old rats. The results suggest that NSAID therapies designed to influence the onset of AD should be initiated in adults before age-associated inflammatory processes within the brain have a chance to develop.

Serum autoantibodies to brain in Landau-Kleffner variant, autism, and other neurologic disorders

OBJECTIVE

Etiologically unexplained disorders of language and social development have often been reported to improve in patients treated with immune-modulating regimens. Here we determined the frequency of autoantibodies to brain among such children.

DESIGN

We collected sera from a cohort of children with (1) pure Landau-Kleffner syndrome (n = 2), (2) Landau-Kleffner syndrome variant (LKSV, n = 11), and (3) autistic spectrum disorder (ASD, n = 11). None had received immune-modulating treatment before the serum sample was obtained. Control sera (n = 71) were from 29 healthy children, 22 with non-neurologic illnesses (NNIs), and 20 children with other neurologic disorders (ONDs). We identified brain autoantibodies by immunostaining of human temporal cortex and antinuclear autoantibodies using commercially available kits.

RESULTS

IgG anti-brain autoantibodies were present in 45% of sera from children with LKSV, 27% with ASD, and 10% with ONDs compared with 2% from healthy children and control children with NNIs. IgM autoantibodies were present in 36% of sera from children with ASD, 9% with LKSV, and 15% with ONDs compared with 0% of control sera. Labeling studies identified one antigenic target to be endothelial cells. Antinuclear antibodies with titers >/=1:80 were more common in children with ASD and control children with ONDs.

CONCLUSION

Children with LKSV and ASD have a greater frequency of serum antibodies to brain endothelial cells and to nuclei than children with NNIs or healthy children. The presence of these antibodies raises the possibility that autoimmunity plays a role in the pathogenesis of language and social developmental abnormalities in a subset of children with these disorders.

In the absence of T cells, natural killer cells protect from mortality due to HSV-1 encephalitis

The importance of natural killer (NK) cells in the resistance to herpes simplex virus type 1 (HSV-1), a common infection of immunocompromised patients, is unclear. Previous data on the role of NK cells in murine HSV-1 infection has been contradictory. Adoptive transfer studies suggested that NK cells mediated resistance to HSV-1, but in vivo depletion approaches demonstrated that NK cells were not important. We studied the course of HSV-1 infection after intranasal (i.n.) inoculation of E26 mice (lacking NK and T cells), T cell knockout (T cell ko) mice (lacking T cells only), or normal control mice. The E26 mice showed greater mortality and an impaired ability to clear virus from lung and brain compared to T cell ko mice and control mice, and had severe necrotizing HSV-1 encephalitis. Therefore, the data support the hypothesis that NK cells play an important role in the natural defense of murine HSV-1 infection.

Interleukin-8 receptor B immunoreactivity in brain and neuritic plaques of Alzheimer's disease

Cytokines mediate inflammatory responses through their receptors in the hematopoietic system. In a search for potential mediators of inflammatory responses in Alzheimer's disease, we examined brain for cytokine receptors. Herein we describe interleukin-8 receptor B (IL-8RB, also termed CXCR2) immunoreactivity in the central nervous system. Strong IL-8RB immunoreactivity is present in both Alzheimer's disease and control brains. Neurons, dendrites, and axons are clearly immunoreactive. In Alzheimer's disease, IL-8RB immunoreactivity is also present in some swollen dystrophic neurites of neuritic plaques. Double staining and confocal microscopic analysis reveals that these IL-8RB-positive neurites in plaques are neurofilament positive and are distinct from astrocytic or microglial processes. In general, these IL-8RB-positive neurities do not co-localize with PHF-1 or AT8 (hyperphosphorylated tau) immunoreactive neurites but instead co-localize with beta PP-positive neurites. These results demonstrate for the first time IL-8RB immunoreactivity in the central nervous system and imply a new role for this receptor outside the hematopoietic system. The strong presence of IL-8RB on neurons and the potential of glial cells to produce IL-8 suggest that this system might mediate neuronal-glial interactions.

Progressive supranuclear palsy with fronto-temporal atrophy and various tau-positive abnormal structures

An autopsy case of a 67-year-old man with typical clinical features of progressive supranuclear palsy (PSP) characterized by impairment of vertical ocular pursuit movement, pseudobulbar palsy, nuchal stiffness, parkinsonism, and dementia is described. In addition to typical pathological changes of PSP, the present case showed fronto-temporal cortical atrophy, accompanied with various Gallyas/tau-positive neuronal and glial structures such as neurofibrillary tangles, pretangle neurons, glial coiled bodies, astrocytic plaques and argyrophilic threads in the cerebral cortex and subcortical nuclei, and many senile plaques throughout the whole cerebral cortex. The present report suggests that PSP and corticobasal degeneration share a common background in neuronal and glial pathologies, that pathological changes of PSP and Alzheimer's disease are mixed in the entorhinal cortex, amygdala. Meynert nucleus, and hypothalamus, and that dementia with frontal lobe-like syndrome in PSP is related to the frontal and temporal cortical pathologies, and is cortical dementia as well as subcortical dementia.

Comparative investigation of neurofibrillary damage in the temporal lobe in Alzheimer's disease, Down's syndrome and dementia pugilistica

Neurofibrillary lesions such as neurofibrillary tangles, neurites and neuropil threads are used as neuropathological markers of Alzheimer's disease (AD). However these lesions are also seen in non-demented elderly cases as well as in several other disorders such as Down's syndrome (DS), dementia pugilistica (DP) and Parkinson's disease. Quantitative studies may therefore help in understanding the pathophysiological role of these lesions. Using a novel image analysis technique we have quantified the extent of neurofibrillary damage in AD, DS and DP. We have found that the extent of neurofibrillary change did not significantly differ between AD and DS, though there were also strong parallels between AD and DP. We conclude that both genetic (as in DS) and environmental (as in DP) risk factors for AD-type pathology provide a similar pattern of neurofibrillary degeneration to that in AD itself suggesting that similar degenerative mechanisms might be triggered in all three conditions.

Different variants of frontotemporal dementia: a neuropathological and immunohistochemical study

Histological and immunohistochemical findings in 20 cases of frontotemporal dementias-8 cases of dementia of frontal lobe type (DFT), 7 cases of Pick's disease (PD), and 5 cases of motor neuron disease with dementia (MND/D)-are presented. Common features of all three syndromes were: frontotemporal atrophy, involvement of subcortical nuclei, and swollen chromatolytic cells. Ubiquitin (Ub)-positive and tau-negative inclusions in cortical, hippocampal, and motor neurons were found in MND/D and DFT cases, suggesting a common pathogenesis of MND/D and DFT. MND/D showed the same cytoskeletal alterations in motor nuclei as MND without dementia: Bunina bodies and skein-like, Ub-positive inclusions. DFT differed from PD in the preponderance of histopathological changes in upper cortical layers, the sparseness of chromatolytic cells, and the absence of tau-positive Pick bodies (PBs). There were, however, two transitional cases showing Pick-type histology but no PBs, thus linking DFT and PD. PBs expressed chromogranin B and secretoneurin strongly, but chromogranin A only weakly. They were negative for the 70-kDa heat-shock protein, metallothionein, and glutathione-S-transferase.

White matter amyloid in Alzheimer's disease brain

Amyloid beta-protein (A beta) deposits in the white matter were investigated by the double immunohistochemical staining for A beta and neuritic, glial or vascular components. Reactive astroglia and neurite abnormality were absent around A beta deposits in the white matter (w-A beta) even those with a core. The association of w-A beta with blood vessels was not consistent. Aggregates of activated microglia were found to be the sole but a consistent accompaniment of A beta deposits even in the absence of other components such as neuron, synapse, neurite abnormality and reactive astroglia, as observed in the white matter. This suggests that the aggregates of activated microglia most likely represent one of the factors promoting the process of A beta deposition.

Interleukin-1 expression in different plaque types in Alzheimer's disease: significance in plaque evolution

The histologically apparent polymorphism of plaques containing beta-amyloid in Alzheimer's disease is thought to represent different stages in plaque evolution. beta-amyloid-immunopositive plaques were classified according to the pattern of beta-amyloid distribution (diffuse vs dense-core) and the presence or absence of dystrophic beta-amyloid precursor protein-immunopositive (beta-APP+) neurites (neuritic vs non-neuritic). The potential contribution of microglia-derived interleukin-1 (IL-1), an immune response cytokine that induces synthesis and processing of beta-APP, to the possible sequential development of these plaque types was examined through determination of the number of IL-1 alpha+ microglia associated with each of four identified plaque types. Diffuse non-neuritic plaques had the least dense and most widely dispersed beta-amyloid, did not exhibit beta-APP+ dystrophic neurites, but most (78%) contained activated IL-1 alpha+ microglia (2 +/- 0.2/plaque; mean +/- SEM). Diffuse neuritic plaques had more dense, but still widely dispersed beta-amyloid, displayed a profusion of beta-APP+ dystrophic neurites, and had the greatest numbers of associated activated IL-1 alpha+ microglia (7 +/- 0.8/plaque). Dense-core neuritic plaques had both compact and diffuse beta-amyloid and had fewer IL-1 alpha+ microglia (4 +/- 0.4/plaque). Dense-core, non-neuritic plaques had compact beta-amyloid, lacked associated diffuse beta-amyloid, and were devoid of both IL-1 alpha+ microglia and beta-APP+ dystrophic neurites. These results suggest an important immunological component in the evolution of amyloid-containing plaques in Alzheimer's disease and further suggest that IL-1-expressing cells are necessary to initiate dystrophic neurite formation in diffuse beta-amyloid deposits.(ABSTRACT TRUNCATED AT 250 WORDS)

Increase in [3H]cAMP binding sites and decrease in Gi alpha and Go alpha immunoreactivities in left temporal cortices from patients with schizophrenia

To search for possible alterations in second messenger systems in the temporal cortex (Brodmann's area 22) of patients with schizophrenia, we measured the binding activities of [3H]adenosine 3',5'-cyclic monophosphate ([3H]cAMP) and [3H]4 beta-phorbol 12,13-dibutyrate ([3H]PDBu) which can label the regulatory subunit of cAMP-dependent protein kinase (protein kinase A) and the regulatory domain of Ca2+/phospholipid-dependent protein kinase (protein kinase C), respectively. We also immunoquantified the variable subunits of guanine nucleotide binding proteins (G-proteins), using specific polyclonal antisera against Gs alpha, Gi alpha and Go alpha. Brains were obtained at autopsy on 10 patients with schizophrenia and 10 age-matched control subjects. Representative Scatchard plots for specific [3H]cAMP bindings to the soluble fraction consisted of a single component with high affinity (Kd = 2.36 nM, Bmax = 737 fmol/mg protein). Among the tested adenyl and guanyl nucleotides, or neuroleptics, cAMP alone potently inhibited the binding (Ki = 4.95 nM). The binding sites for [3H]cAMP were discretely localized, and were in the order of: cerebral cortex = hypothalamus = amygdala > hippocampus = neostriatum = thalamus = nucleus accumbens > globus pallidus = cerebellum. Specific [3H]cAMP bindings to the soluble fractions were about 30% greater in the left temporal cortices of schizophrenic patients, as compared to findings in the right side of the patients and the left side of the control subjects, no control brain showed this asymmetry. The specific [3H]PDBu binding in schizophrenic and control groups did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

Alz-50 antibody recognizes Alzheimer-related neuronal changes

Alz-50 is a monoclonal antibody directed against an antigen present in Alzheimer's disease. Unlike conventional pathological stains that reveal only neurons with neurofibrillary tangles (NFTs), Alz-50 recognizes neurons that contain NFTs and additional neurons that do not. Our investigation of the topographical distribution of both NFT-containing and non-NFT-containing neurons recognized by Alz-50 reveals that they are both found primarily in certain cytoarchitectural areas and lamina that have been established as consistent sites for NFT pathology. Some of the neurons recognized by Alz-50 appear histopathologically normal. We suggest that Alz-50 recognizes an antigen in neurons that both precedes and accompanies NFT formation. Thus, it may mark a point early in cellular pathology before irreversible cytoskeletal and degenerative changes occur.

Antibodies to normal and Alzheimer human brain structures from non-immunised mice of various ages

Supernatants from mouse spleen hybridoma lines established without previous immunisation were screened immunohistochemically against cryostat sections of human temporal cortex and found to stain a variety of brain structures, including Alzheimer plaques and tangles. The age of the mice had no effect on antibody production.

Carotid artery thrombosis, encephalitis, myelitis and optic neuritis associated with rubella virus infections

The clinical, virological and pathological findings in 5 patients with neurological complications associated with rubella virus infection are described. The neurological illnesses began four to ten days after the rubella illnesses. The patients were all males aged between 6 and 17 years and were diagnosed during one non-epidemic year in a population of 1-5 million people. All the patients had rubella specific IgM in their sera. Two patients had no rash. In one of the patients who died, left internal carotid artery thrombosis and cerebral infarction were found at post-mortem. Rubella virus antigen and particles resembling rubella virus were found in the brain together with IgG and IgM in the same areas. This patient also had extensive liver necrosis. The other patient had a severe meningomyelitis and radiculitis and he recovered completely after two years. His serum rubella antibody rose significantly and was shown to leak into CSF during the acute stage of his illness. Three patients had a rash. Two of these patients had encephalitis: one recovered completely and the other had residual disability. The third patient had bilateral optic neuritis from which he recovered completely. Rubella specific IgM was, however, present in his serum for the abnormally long time of twenty-eight weeks indicating possible persistence of rubella virus.