Development and expression of cytoplasmic antigens in Purkinje cells recognized by monoclonal antibodies. Studies in neurologically mutant mice

Presence of calbindin D28K and GAD67 mRNAs in both orthotopic and ectopic Purkinje cells of staggerer mice suggests that staggerer acts after the onset of cytodifferentiation

We used in situ hybridization to study the expression of GAD67 and calbindin D28K mRNAs in developing mouse cerebellar Purkinje cells. Both genes are expressed prenatally; calbindin D28K mRNAs can be detected in Purkinje cells of embryonic day (E) 15 mice, whereas GAD67 mRNAs first appear slightly later, in E16 mice. The stunted Purkinje cells of staggerer (sg/sg) mutant mice maintain calbindin D28K and GAD67 expression. Our data suggest that the sg/sg mutation does not interfere with the transcriptional activation of these two genes, and might therefore act after the induction of specific gene expression in developing Purkinje cells.

Cerebellar degeneration in the Niemann-Pick type C mouse

Chronological morphological changes and topographical distribution of degenerating Purkinje cells were studied in the murine model of Niemann-Pick disease type C (NPC mouse). Loss of Purkinje cells can be detected in the anterior vermis as early as 60 days of age, coinciding with early neurological signs, and progressed to total absence in the entire hemisphere and vermis with exception of nodules. Ultrastructurally, concentric lamellar inclusions were detected in the perikarya of degenerating Purkinje cells as well as in the focally enlarged branching points of their dendrites. Calbindin immunocytochemistry demonstrated dendritic pathology characterized by irregular contour of dendritic trees and decreased number of dendritic spines. Ubiquitin immunoreactivity revealed granular reaction products in the perikarya, dendrites and axons of Purkinje cells. Our studies demonstrated unique pathological features of Purkinje cells that involve perikarya, dendrites and axons in the NPC mouse.

A monoclonal antibody that labels Purkinje cells in the rat cerebellum

A monoclonal antibody (MAb-1D10), generated by immunizing Balb/c mice with homogenized bovine retinal tissue, labeled the Müller cells in the bovine retina and the Purkinje cells of the rat cerebellum. In the neonatal rat cerebellum, immunoreactivity for MAb-1D10 appeared first in the ventral regions of vermis (lobuli I-III and IX-X) on the 11th postnatal day (P11), while in the dorsal vermis and cerebellar hemisphere, the immunoreactive Purkinje cells were detected on P13. Western blotting analysis disclosed that MAb-1D10 recognized bovine retinal polypeptides with mol.wt. of 48 kDa. Transplantation of the rat cerebellar primordia on 16th embryonic day demonstrated large and round cells with a linear arrangement in the grafts surviving well in the host rat striatum after 50 days of the grafting. These large cells were immunohistochemically labeled by MAb-1D10. No other cells in both the graft and the host striatum were immunoreactive to the MAb.

Immunohistochemical expression of P400 protein in Purkinje cells of sphingomyelinosis mouse

Immunohistochemical expression of P400 protein, a glycoprotein localized to the Purkinje cell membrane, has been studied in the cerebellum of spm mouse using anti-P400 monoclonal antibody. The initial change observed in the Purkinje cells was a swelling of the cell body with distortion of the neurites; this occurred as early as 5 weeks of age. A significant, patchy loss of Purkinje cells started at 6 weeks before cerebellar signs became manifest. With progression of the disease the dendritic processes in the molecular layer showed a marked swelling, followed by irregular arborization and finally by disintegration. A few, heterotopic Purkinje cells were found in the subcortical white matter; this was interpreted as an indication that a disturbance in neuronal migration could be superimposed on the sphingolipid metabolic disorder. Additionally, P400-immunoreactive nerve cells were occasionally encountered in areas of the deep cerebellar nuclei and in the lateral vestibular nuclei of the pontine tegmentum. The number of P400-immunoreactive Purkinje cells correlated well with the percentages of the remaining Purkinje cells during the ages of 4 to 7 wks. At the late stage of 10 to 12 weeks almost all Purkinje cells had lost their P400-immunoreactivity. It is suggested that Purkinje cells that fail to express P400 protein may undergo an immunohistochemical degeneration of the plasma membrane.

Expression of a developmental stage-specific antigen by neuronal precursor cells of human fetal cerebellum

A monoclonal antibody that was prepared against human neuroblastoma cells was shown to react strongly with fetal brain and moderately with adult brain by quantitative absorption testing. Immunoperoxidase staining demonstrated expression of the antigen by neuronal precursor cells in the cerebellar external granular layer of a 24- to 26-week fetus but not by their mature derivatives in the granular and molecular layers of adult cerebellum. The antigen was also present on subventricular cells of fetal cerebral cortex, as well as adult and fetal astrocytes. The expression of this antigen by neuronal precursor cells in the external granular layer but not their mature derivatives suggests that it is a stage-specific marker for cerebellar neuronal development.

Some immature tetanus toxin-positive cells share antigenic properties with subclasses of glial cells. An immunofluorescence study in the developing nervous system of the mouse using a new monoclonal antibody S1

Monoclonal antibody S1 reacts in monolayer cultures with the cell surfaces of oligodendrocytes and a subclass of astrocytes derived from early postnatal mouse cerebellum, cerebrum and spinal cord, as well as with some glial cells in mouse retina but not in dorsal root ganglia. At earlier developmental stages S1 antigen is present in addition to oligodendrocytes and astrocytes on some tetanus toxin-positive neurons. S1 antigen is a developmentally early marker, detectable already in freshly trypsinized single cell suspensions from cerebella of 13-day-old embryos. Immunocytolysis of S1 antigen-bearing cells leads to reappearance of S1 positive glial cells but not tetanus toxin receptor-positive neurons. S1 antigen is also expressed in rat, rabbit, chicken and human. When cultured cells are permeabilized with denaturing agents, S1 antibody not only labels cell surfaces of some glial cells and, depending on the developmental stage, some neuronal cells but also intracellular components of all astrocytes, oligodendrocytes, neurons and fibroblasts.

Architectonic and hodological organization of the cerebellum in reeler mutant mice

The architectonic and hodologic organization of the reeler cerebellum has been studied by means of immunohistochemistry, general cell and fiber stains and by horseradish peroxidase and autoradiographic tracing methods. Malposition of Purkinje cells, which varies in degree, is the most salient architectonic anomaly of the mutant cerebellum. Mapping the distribution of Purkinje cells is facilitated by a monoclonal antibody which selectively stains neurons of this class in the cerebellum. Although some Purkinje cells form a normal monolayer, most lie in heterotopic positions within or below the granule cell layer. The major contingent is segregated in subcortical masses in the depths of the cerebellum. Fiber bundles continuous with the cerebellar peduncles run in septa between the subcortical Purkinje cell masses. The distribution of Purkinje cell masses as well as the roof nuclei and areas of normal cortex and fiber bundles are identical from animal to animal. These consistent architectonic variations serve to partition the reeler cerebellum into 7 sagittally oriented compartments: one medial, two intermediate, two lateral and two additional lateral lobular appendages which may correspond to paraflocculus and/or flocculus of the normal cerebellum. The topography of the reeler olivocerebellar, or climbing fiber, system is normal in that the caudal-to-rostral axis of the olivary complex maps onto the medial-to-lateral axis of the contralateral hemicerebellum. The climbing fiber projection in reeler, like that of the normal animal, appears to be organized in parasagittal strips. In the mutant, mossy fibers from the pons and spinal cord project respectively to the lateral and medial cerebellar fields, and overlap in the intermediate compartment. They thus invest different and to a large extent complementary cerebellar territories, which approximate the architectonic divisions. This segregation of the two principal mossy fiber systems is not so marked in the normal cerebellum. In terms of laminar distribution, the pontine projection is distributed principally to the granule cell stratum in the mutant. The reeler spinocerebellar afferents, by contrast, project not only to the granule cell layer but also to the heterotopic Purkinje cells. The present observations suggest that the primary defect in the reeler cerebellum is malposition of Purkinje cells. As appears to be the case during development of the forebrain in reeler, the mutation may affect the terminal phase of migration of Purkinje cells in the cerebellum.(ABSTRACT TRUNCATED AT 400 WORDS)

Maintenance of immunocytologically identified Purkinje cells from mouse cerebellum in monolayer culture

Purkinje cells were identified in monolayer cultures obtained from trypsin-dissociated cerebella of embryonic and early postnatal mice by the Purkinje cell-specific monoclonal antibodies PC1, PC2, PC3 and UCHT1. These cells also expressed the neuronal marker L1 antigen but not the glial markers, glial fibrillary acidic protein or 04 antigen. They also expressed tetanus toxin receptors, PC4, M1 and Thy-1 antigens. Survival of Purkinje cells was best: (a) when cerebella were taken from mice not older than one day of age: (b) when cells were seeded at higher plating densities; and (c) cultured in chemically defined medium which facilitates the survival of neurons. No Purkinje cells could be detected in cultures from mice older than 6 days. PC1 antigen expression developed in vitro on the same time scale as in vivo, i.e. it was first detectable at the equivalent of postnatal days 3-4. At this stage cell bodies had a size of 13-14 micron in diameter and few processes. Dendrite-like arborizations, with more than one primary dendrite, extension of usually only one thin and long (0.5-1.6 mm) axon-like process and collaterals directed preferentially towards other Purkinje cells, developed with time in culture until the final form was reached by the equivalent of approximately day 16. Cell body size was 18-19 micron in diameter at this stage. Cell shapes were reminiscent of those described in certain cerebellar mouse mutants and in experimentally produced agranular cerebella. Many ultrastructural features of these cells correlated with those described for the in vivo counterpart. However, there was a lack of spiny branchlets and abnormally long persisting somatic spines. Synaptic contacts of the 'en passant' type could be seen at the Purkinje cell soma. Gray type I synapses were seen on Purkinje cell dendrites and spines.

Specificity of monoclonal antibody N1 for cell surfaces of mouse central nervous system neurons

Monoclonal antibody N1 reacts by indirect immunofluorescence with the cell surface of tetanus toxin-positive neurons from early postnatal mouse cerebellum. In freshly trypsinized single cell suspensions from early postnatal mouse cerebellum, 5-10% of all viable cells express N1 antigen on their surface. After 3-24 h of maintenance in vitro all N1 antigen-positive cells are tetanus toxin-positive. After culture periods of 3-4 days, most (approximately 90%) tetanus toxin-positive cells express N1 antigen on their surface. When horse serum-supplemented medium (HSSM) is used for cultivation, neurons begin to lose N1 antigen from their surface after about one week in vitro, until after two weeks in vitro, N1 antigen is no longer detectable, although some tetanus toxin-positive neurons can be shown to survive in culture. In defined medium, however, N1 antigen-positive neurons can still be detected after 34 days in vitro, the longest culture period examined so far. Complement-dependent immunocytolysis deletes all N1 antigen-positive and approximately 90% of all tetanus toxin-positive neurons from cultures. The remaining neurons reveal a morphology different from the one of the majority of small neurons, the granule cells. They have slightly larger cell bodies and several branched and unbranched cellular processes. Neonatal cerebellar cells show the same temporal sequence of appearance and disappearance of N1 antigen on most tetanus toxin-positive neurons in HSSM, and a persistence of N1 antigen on neurons in defined medium. N1 antigen becomes first detectable at embryonic day 17, and never becomes detectable in cell cultures derived from cerebella of younger mice. At all stages studied, N1 antigen expression is restricted to tetanus toxin-positive neurons, while it is absent from the cell surfaces of astrocytes, oligodendrocytes and fibroblasts. N1 antigen is also found in cultures derived from early postnatal mouse cerebrum, but is not detected in cultures derived from mouse retina, spinal cord, dorsal root ganglion, and embryonic telencephalon. It is also not detectable in cerebellar cultures from rabbit, rat, chicken and human. When N1 antibody is applied to fixed cultures where intracellular antigens are accessible, all cell types are labeled intracellularly, with astrocytes and fibroblasts revealing a fibrillary, vimentin-like staining pattern.

Isolation and immunohistochemical localization of a cerebellar protein

Our previous report described that a protein called spot 35 is found in the cerebellar cytosol of adult rats by two-dimensional gel electrophoresis. In this paper we isolated this protein from the soluble fraction of bovine and rat cerebella and then prepared an antiserum against the bovine protein. This protein shows pI around 5.3 and Mr around 27 kdalton. Determination of the amino acid composition of this protein shows high glutamic acid, aspartic acid and leucine contents. Using the antiserum we examined the immunohistochemical localization of this protein by the peroxidase-antiperoxidase method. Purkinje cells, their dendrites and axons were immunohistochemically stained in the cerebella of adult rats, rabbits and humans. Other cells, such as granule cells and glial cells, and myelin did not react to the antiserum.

Identification and immunocytochemical localization of a human adult brain-specific antigen (HABSA)

A new protein with a molecular weight of 669,000, identified in brain extracts from 4 to 69 years old subjects has been isolated and immunochemically characterized. The antigen is found in human adult brain but not in the brains of human fetuses and newborn infants or in the brains of several other species tested. Immunocytochemically, using the PAP method, the antigen is localized at the surface of some nerve cells and on astrocytes and oligodendrocytes of the cerebral cortex, corpus striatum, pons and medulla. The Golgi epithelial cells with Bergmann's fibers, and the velate and ordinary astrocytes in the cerebellum show immunoreactivity as well.