Effect of immunomodulation on the fate of tumor cells in the central nervous system and systemic organs of mice. Distribution of [125I]5-Iodo-2'-deoxyuridine-labeled KHT tumor cells after left intracardial injection.

The effect of systemic immunomodulation on tumor cell arrest and retention in the central nervous system was studied by following radioactively labeled tumor cells. KHT mouse sarcoma tumor cells were labeled in vitro with [125I]IdUrd, and 1 X 10(5) tumor cells were injected into the left side of the hearts of syngeneic C3H mice. Experimental groups consisted of untreated normal mice, mice pretreated iv with Corynebacterium parvum, and mice chronically infected with Toxoplasma gondii; in this model both groups of immunomodulated mice are protected from developing systemic metastatic tumor, but only Toxoplasma-infected mice have protection against metastatic brain tumor. At time intervals from 1 to 96 hours, groups of mice from each experimental group were killed, and the brain and other organs were monitored for radioactivity to determine the number of viable tumor cells that had been present at the time of death. Normal mice demonstrated significant retention of tumor cells in the brain and kidneys plus adrenals at 96 hours. By contrast, in both groups of immunomodulated mice tumor cells were rapidly eliminated from systemic organs, but tumor cells were significantly retained in the central nervous system even at 96 hours after tumor cell injections. The results indicated that generalized immunomodulation had more effect in elimination of tumor cells from systemic organs than from the brain and that the elimination of tumor cells from the brain in Toxoplasma-infected mice was a delayed phenomenon.

Intralesional immunotherapy of brain tumors with combined Corynebacterium parvum and recombinant interleukin-2 in mice.

Clinical observations and experimental work suggested that inflammatory cells attracted to the brain exert a nonspecific antineoplastic effect. Intralesional treatment of implanted malignant murine brain tumors (KHT sarcomas) with killed Corynebacterium parvum produced an inflammatory cell infiltrate and increased survival in C3H mice relative to that in untreated control C3H mice. This antitumor effect was enhanced when recombinant interleukin-2 was sequentially added as a second intralesional immunomodifier. A high percentage of mice so treated were cured. Inflammatory cells in the brains of treated mice divided for 1-2 weeks, and metabolic activity of astrocytes increased. These findings form the basis for a recently initiated immunotherapy protocol in patients with recurrent glioblastoma multiforme.

Influence of chronic Toxoplasma infection on ethylnitrosourea-induced central nervous system tumors in rats.

Because prior work with mice had revealed remarkable inhibition of central nervous system (CNS) tumor by chronic Toxoplasma infection, the effect of immunomodulation produced by this obligate intracellular parasite was studied in rats which developed CNS tumors following transplacental exposure to the chemical carcinogen ethylnitrosourea. Groups of Fischer 344 rats which had been exposed to ethylnitrosourea were either uninfected or infected at 1 month of age with a virulent strain of Toxoplasma gondii. Rats were sacrificed when morbid symptoms from tumor growth developed, and neural tissue was prepared for light microscopy. Chronic Toxoplasma infection had no effect on the survival of rats or on the amount, location, or histological type of CNS tumor which developed. Although serum antibody to Toxoplasma was present in all infected rats for the duration of the experiment, there was no histological evidence in the brain of a cellular response to infection or to the presence of tumor. When these results are compared to prior experiments of CNS tumor in mice, they suggest that mechanisms of protection against Toxoplasma infection differ in mice and rats and that an inflammatory component produced by the Toxoplasma organism in the brain is a necessary prerequisite for tumor inhibition.

Development of a metastatic brain tumor model in mice.

This study reports an easily accomplished and reliable model of metastatic tumor in the brains of mice. Five experimental groups of female C3H/Bi mice received left intracardiac injections of a syngeneic KHT sarcoma cell suspension (1 X 10(5) cells) and were followed until death. Two groups of mice also received 3,000 rads of radiation to a limited cardiac port 24 hr after tumor injections. All mice were completely autopsied, and the brains were examined both grossly and microscopically. Metastatic brain tumor developed in 60 to 70% of mice; the tumor foci were parenchymal, usually multifocal, and had wide distribution throughout the cerebrum, brainstem, and cerebellum. There was occasional meningeal tumor, but tumor never involved the skull, choroid plexus, pituitary gland, or local extracranial structures. Cardiac irradiation did not increase the number of the mean survival of mice with metastatic brain tumor but did decrease the total tumor burden of individual animals by markedly reducing the incidence of metastatic lung tumor and totally preventing tumor infiltration of the heart. This demonstration of consistently produced blood-borne metastatic brain tumor in mice should provide a valuable research model which will allow the central nervous system to be studied for internal mechanisms and/or external factors which influence the arrest and growth of embolic tumor cells in the brain.

Effect of cyclophosphamide on survival of mice and incidence of metastatic tumor following intravenous and intracardial inoculation of tumor cells.

We studied the effect of cyclophosphamide on survival of mice and the incidence of tumor implants in various organs following both i.v. and intraarterial dissemination of tumor cells. Female C3H/HeN mice received cyclophosphamide (240 mg/kg) i.p. 4 days prior to inoculation of various doses of KHT tumor cells. Mice were followed to death, and the amount of tumor present was roughly quantified. Following i.v. inoculation of tumor cells, survival was decreased in cyclophosphamide-treated mice compared to control mice. However, survival was not affected by treatment with cyclophosphamide in mice receiving intracardial tumor cell injections. Pretreatment with cyclophosphamide caused a dramatic increase in the number of lung tumor implants following both routes of tumor cell administration. A similar tumor-promoting effect by cyclophosphamide could not be documented in the brain, heart, kidney, adrenal, or ovary. The study suggests that cyclophosphamide has a much greater effect on ultimate deposition and growth of tumor implants in the lungs than in other systemic organs or in the central nervous system.

Extraction and immunocytochemical characterization of viable mononuclear inflammatory cells from brains of mice with chronic Toxoplasma gondii infection.

A method which combined mechanical and enzymatic dissociation of brain parenchyma with Percoll density gradient centrifugation of the resulting tissue suspension was developed for the extraction of viable mononuclear inflammatory cells from the brains of mice. This method was used to extract mononuclear inflammatory cells from the brains of normal mice and mice chronically infected with the intracellular parasite Toxoplasma gondii. Infection with T. gondii was found to result in a 5- to 7-fold increase in the number of mononuclear cells which could be extracted from mouse brains. Immunocytochemical characterization of the extracted mononuclear cell fractions using monoclonal antibodies against T cell subsets and monocyte/macrophages revealed that the numbers of helper T cells, cytotoxic/suppressor T cells, and monocyte/macrophages present in mouse brain increased markedly after infection with T. gondii. This method may prove useful in identifying the cells responsible for inhibition of growth of tumor cells in the brain which has been observed after infection with T. gondii in mice.

Cell adhesion molecules on vessels during inflammation in the mouse central nervous system.

The expression of endothelial cell adhesion molecules (CAMs) in the central nervous system (CNS) of the mouse was examined during an inflammation induced by intracerebral injection of killed Corynebacterium parvum (C. parvum). We showed that injection of killed C. parvum produced an inflammatory cellular infiltrate limited to the injected brain hemisphere. However, the upregulation of ICAM-1 and VCAM-1 on brain endothelium occurred starting 2 days after C. parvum injection throughout the entire CNS and was not restricted to vessels surrounded by a cellular infiltrate. In contrast to the systemic upregulation of ICAM-1 and VCAM-1, cerebral vessels located in the center of the cellular infiltrate started to express the MECA-32 antigen, suggesting an altered functional status of the endothelial cells, as this antigen is suppressed during development of the blood-brain barrier (BBB). Binding assays performed on frozen sections of inflamed brains are consistent with an important role for endothelial VCAM-1 in the recruitment of lymphocytes during inflammation in the CNS of the mouse.

Indium-111-labeled autologous platelets for location of vascular thrombi in humans.

Twenty-two patients suspected of having either venous or arterial thrombi were studied with In-111-labeled autologous platelets. Whole-body scans were performed 3, 24, and 48 hr following i.v. injection. Twelve patients studied with saline-washed platelets had unsatisfactory 15-min recovery and biologic half-time. When the labeling was carried out in plasma, these values compared favorably with normal values reported for Cr-51-labeled autologous platelets. Of ten patients studied using platelets labeled in plasma, three had normal scans, six had abnormal scans, and one had an equivocal scan. All six abnormal scans were confirmed with corresponding positive findings in either the venogram, arteriogram, or lung scan. J Nucl Med 19: 626-634, 1978.

Toxoplasma gondii infection of the central nervous system. Use of the peroxidase-antiperoxidase method to demonstrate toxoplasma in formalin fixed, paraffin embedded tissue sections.

The peroxidase-antiperoxidase immunohistochemical technique was employed to stain formalin fixed, paraffin embedded tissue sections from three cases of encephalitis caused by Toxoplasma gondii. We studied two cases of congenital infection and one case of acquired toxoplasmosis occurring in an immunocompromised host. The peroxidase-antiperoxidase method was exquisitely sensitive and highly specific and stained both the encysted and tachyzoite forms of the organism, as well as allowing for easy identification of infected cells. In two cases of necrotizing encephalitis--one congenital, the other acquired--widespread dissemination of the Toxoplasma organism throughout the neural parenchyma was visualized using the peroxidase-antiperoxidase stain. Brain biopsy material that had been obtained eight days prior to death in the case of adult acquired toxoplasmosis did not contain any of the characteristic tissue cysts and was not diagnostic for toxoplasmosis by conventional staining techniques. However, peroxidase-antiperoxidase staining of tissue sections from this biopsy unequivocally demonstrated both free tachyzoites and multiple infected cells. Further application of the peroxidase-antiperoxidase method should increase our understanding of the pathology and pathogenesis of toxoplasmic encephalitis as well as allowing timely diagnosis in cases presenting with neurologic symptomatology.

Toxoplasma encephalitis in patients with acquired immune deficiency syndrome: diagnosis and response to therapy.

Although Toxoplasma gondii is the most commonly recognized cause of central nervous system mass lesions in patients with acquired immune deficiency syndrome, published investigations have provided little information about criteria for diagnosis of toxoplasmosis or the response to therapy. In this series the method of diagnosis and response to therapy were assessed in 14 patients who had evidence for toxoplasmosis based on routine histopathology, immunoperoxidase staining, or mouse inoculation. These patients presented with clinical and radiologic findings that did not clearly distinguish them from patients with other infectious or neoplastic processes. Excisional biopsies usually showed tachyzoites on routine histology, but needle biopsies were usually negative unless mouse inoculation or immunoperoxidase staining was employed. Response to pyrimethamine and sulfadiazine therapy was often prompt, but therapy had to be continued for long periods of time to maintain a clinical response, and no alternative regimen of one or more drugs appeared to be effective in patients unable to tolerate both pyrimethamine and sulfadiazine.

MR imaging in an experimental model of brain tumor immunotherapy.

A murine model of implanted CNS neoplasia was used to study a new form of brain tumor immunotherapy with intralesional Corynebacterium parvum (C. parvum). Assessment of treatment protocols has been limited by the inability to assess, noninvasively, tumor burden and/or the inflammatory reaction induced in the murine brain by treatment with C. parvum. This study demonstrates that contrast-enhanced MR imaging can monitor in vivo tumor burden and the immune response to intracerebral C. parvum. KHT murine sarcoma was stereotaxically implanted into the right frontal lobe of C3H/HeN mice at doses of 10,000 and 50,000 tumor cells. The KHT sarcoma is 100% fatal in untreated mice. Therapy consisted of an intraperitoneal injection of 350 micrograms of killed C. parvum 1 day after tumor implantation followed by 70 micrograms of C. parvum stereotaxically injected into the tumor 5 days after implantation. MR imaging was performed on mice injected with saline only, C parvum only, tumor only, and tumor treated with C. parvum. C. parvum alone elicited an intense transitory mononuclear cell inflammatory reaction in the meninges, ependyma, and to a variable degree at the injection site. The inflammatory response reached a peak 2 weeks after intracerebral injection. Contrast-enhanced MR imaging was able to detect the presence and severity of C. parvum-induced inflammation, which decreased 3 weeks after intracerebral injection. The transitory nature of this type of inflammation should allow its differentiation from tumor in subjects undergoing serial scanning following intracerebral injection of C. parvum as a form of brain tumor immunotherapy.

Embolization of a superficial temporal artery to middle cerebral artery bypass: case report.

This case history of a man with bilateral carotid artery occlusions presents angiographic documentation of the embolization of a superficial temporal-middle cerebral artery bypass. The embolic source was thrombotic and/or atheromatous debris that had collected in the persistent stump of one of the occluded internal carotid arteries.

Metastatic brain tumor model in mice that mimics the neoplastic cascade in humans.

This study reports a model of metastatic tumor to the brains of mice. A sequentially colonized brain-homing tumor line was developed from the KHT sarcoma and was injected into the right hind foot of syngeneic C3H female mice. When tumor was just grossly apparent in the foot, the tumor-bearing leg was amputated at the midthigh level, thus surgically curing each mouse of its primary tumor. Mice were followed to death and were autopsied for evidence of metastatic tumor. All mice had metastatic pulmonary tumor nodules, and approximately 80% of the mice had metastatic deposits of tumor in the brain. Because this model mimics the situation in humans where patients die of metastatic disease at some time after the removal of their primary cancer, it should be of value in further delineating factors that influence the development and growth of metastatic tumor in the central nervous system.

Postoperative cervical pseudomeningocele as a cause of delayed myelopathy.

A spinal cord-injured patient developed progressive myelopathy 6 months after operative decompression of the cervico-medullary junction. At the time of the initial operation, the dura mater had been left open. A computed tomographic body scan revealed a cervical pseudomeningocele, which was repaired surgically. After operation, there was reversal of the patient's progressive neurological dysfunction.

Epidermoid tumors involving the fourth ventricle.

The case histories of three patients with epidermoid tumors of the 4th ventricle treated by surgical excision are presented. All three cases exhibited a prolonged latent period from the onset of symptoms to the final diagnosis. Despite the strategic location and enormous size of all three tumors, only one of the patients had significant hydrocephalus. The radiographic diagnosis and differential diagnosis of epidermoid tumors are discussed.

Effect of radiation therapy on hemangioblastoma: a case report and review of the literature.

A case of medullary hemangioblastoma treated with radiation and operation is presented. After radiation a 55% decrease in the volume of the vascular portion of the tumor was documented by angiograms. Also, there were planes of dissection between the tumor and the dorsal medulla that had not been appreciated at exploratory operation before radiation. Total resection of the tumor was accomplished using hypothermia and cardiac standstill. The literature detailing the effects of radiation on hemangioblastoma is reviewed. (Neurosurgery, 6: 82--86, 1980)

Deficits of higher cortical functioning in two patients with posterior parietal arteriovenous malformations. Use of the standardized Luria-Nebraska Neuropsychological Battery for pre- and postoperative assessment.

The Standardized Luria-Nebraska Neuropsychological Test Battery was used for pre- and postoperative evaluation of two patients, each of whom had a large posterior parietal arteriovenous malformation (AVM) of the left cerebral hemisphere. In both cases the AVMs, which were fed by the left anterior, middle, and posterior cerebral arteries, were resected completely. These cortical lesions, which were almost identical in anatomical location and pathophysiology, produced deficits in higher cortical functioning that were remarkably similar in the two patients studied. Disorganization of spatially based complex speech and confusion with arithmetic and writing functions were the most prominent pre- and postoperative problem areas. Other functions that had been mildly abnormal preoperatively had improved at the last testing session 6 months postoperatively. The test battery is easy to administer, has standardized scoring, requires only 2.5 hours of testing time, and produces reliable, reproducible results. Our initial experience with this test battery suggests that it is readily applicable to patients with neurosurgical disease and may be of benefit in planning appropriate rehabilitation and in obtaining knowledge that will increase our understanding of complex brain functions.

Decompression of lumbar spinal stenosis and stabilization with Knodt rods in the elderly patient.

We present a series of 25 elderly patients who exhibited signs and symptoms of neurogenic claudication and who were found to have one or two levels of spinal stenosis. At the time of decompressive surgery, excessive movement was found at the stenotic levels, so a simple stabilization procedure was performed using Knodt rods and a facet fusion. The expectation was that spine fixation would decrease the amount of postoperative back pain, which can be a result of continued abnormal mobility. All of the patients have been followed for 2 or more years. This elderly group of individuals tolerated surgery well, and long-term results were good.

Effect of intracerebrally injected Corynebacterium parvum on the development and growth of metastatic brain tumor in mice.

Using KHT tumor in a mouse metastatic tumor model, we examined the effect of intracerebral and/or intraperitoneal injections of Corynebacterium parvum on the growth of metastatic brain tumor and the development of an inflammatory response in the central nervous system (CNS). C. parvum given intraperitoneally had no effect on the development and growth of CNS tumor, but did prolong the survival of mice by inhibiting the growth of systemic metastatic tumor, which was the cause of death in our tumor model. Mice that received intracerebral injections of C. parvum exhibited significantly decreased growth of metastatic brain tumor, as compared with mice that received intracerebral injections of saline, whether or not they had received C. parvum intraperitoneally. In addition, the brains of mice that received C. parvum intracerebrally exhibited an inflammatory response that was minimal or absent in the brains of control mice. Our results suggest that if immunotherapeutic agents can be delivered to the CNS and cause an inflammatory response, they can be effective against CNS metastases.

Progressive neurological dysfunction secondary to postoperative cervical pseudomeningocele in a C-4 quadriplegic. Case report.

A case is detailed of a patient who developed progressive neurological deficit above a fixed quadriplegic level at C-4 18 years after posterior cervical decompression for trauma. Diagnostic evaluation revealed a pseudomeningocele at the site of his previous surgery. Subsequent operative closure resulted in reversal of his neurological symptoms.