Emergence of oligodendrocytes from human neural spheres

To study the development of human oligodendrocyte precursors (OP), we expanded human embryonic brain-derived neural precursors into spheres with basic fibroblast growth factor (FGF2). Over 90% of the cells in the expanded spheres were precursors coexpressing nestin and the polysialylated (PSA) form of NCAM. The remaining cells were mostly astrocytes and neuronal cells located at the periphery of the floating spheres. When spheres were allowed to adhere on fibronectin-coated substrate in the absence of FGF2, neural precursors migrated in the outgrowth and often formed chains of cells expressing high levels of PSA-NCAM. Many migrating cells also expressed beta-3 tubulin while only scattered elongated cells radiating from the spheres were GFAP+ astrocytes. Spindle-shaped cells not associated with the chains were labeled for the PDGF-alpha receptor and often coexpressed MAP2 neuronal isoforms. Neuronal cells in the outgrowth rapidly established a rich neuritic network where OP expressing O4 and DM20/proteolipid antigens appeared. T3 treatment of neural spheres increased the rate of OP formation and the complexity of their shape. Thus, the generation of human oligodendrocytes from neural precursors is tightly correlated with growth of neuronal processes and enhanced by hormonal signals.

Long-term health outcomes and quality of life in American and Italian inception cohorts of patients with juvenile rheumatoid arthritis. I. Outcome status

OBJECTIVE

To assess the long-term health outcomes and quality of life of patients with juvenile rheumatoid arthritis (JRA) using health and functional assessment questionnaires in 2 populations, one from the USA and one from Italy.

METHODS

Patient eligibility criteria: (1) first examined in our units between 1958 and 1990 during the first 6 months after onset of symptoms, (2) diagnosis of JRA by the American College of Rheumatology criteria, (3) disease duration of at least 5 years at the time of assessment of outcome. Instruments used: (1) the Health Assessment Questionnaire (HAQ, short form, or childhood HAQ (CHAQ), and (2) Quality of Life Scales (QOLS, adults only). Eligible patients were identified by computer search and chart review and were then mailed a packet containing a consent/assent form and the assessment instruments.

RESULTS

Of 346 patients who met the eligibility criteria were able to locate 301, and 290 verbally agreed to participate and were mailed packets. Signed consent and complete information were received from 227 of the 290 (78%), 178 from the USA and 49 from Italy. Mean duration of disease at the time of outcome assessment was 15 yrs. 127 had pauciarticular, 55 polyarticular, and 45 systemic onset disease. Mean and (median) scores of the outcomes are shown in the table. [table: see text]

CONCLUSION

Long-term outcome, as assessed by the instruments used, is very favorable in most patients with JRA 5 years or more after onset of symptoms.

The Bentham Unit: a pilot remand and assessment service for male mentally disordered remand prisoners. I: Clinical activity in the first year, and related ethical, practical and funding issues

BACKGROUND

Because of continuing concern regarding the inadequacy of existing NHS provision for mentally disordered remand prisoners, the Bentham Unit was commissioned as a pilot project to provide rapid assessment and, where appropriate, hospital admission for such prisoners from the former North West Thames catchment area.

METHOD

Information is presented on the 150 referrals and 62 admissions in the first year of the service's operation.

RESULTS

The service met the Reed Report targets for assessment time. Most of those referred were previously known to psychiatric services. The alleged offences were more serious than anticipated. Those admitted were transferred to appropriate services at the conclusion of their court cases, and remained in contact with services three months later. Waiting for the conclusion of court proceedings significantly prolonged the length of stay. Substantial cost transfers from the criminal justice system to the health system were evident.

CONCLUSIONS

Adequate services for mentally disordered remand prisoners are entirely achievable; provision of such services is a resource issue, not a clinical problem.

Long-term health outcomes and quality of life in American and Italian inception cohorts of patients with juvenile rheumatoid arthritis. II. Early predictors of outcome

OBJECTIVE

To determine whether demographic, clinical, and immunogenetic variables measurable during the first 6 months of illness long-term health outcomes and quality of life in patients with juvenile rheumatoid arthritis (JRA).

METHODS

Patient eligibility criteria: (1) first examined in our units between 1958 and 1990 within 6 months of onset of symptoms; (2) diagnosis of JRA by American College of Rheumatology criteria; (3) disease duration of at least 5 years at the time of assessment of outcome. Instruments used: (1) the Health Assessment Questionnaire (HAQ, short form), or Childhood HAQ (CHAQ) to measure disability (0-3 scale), (2) pain, and (3) parental assessment of overall well being, each scored on a 15 cm visual analog scale; (4) the Quality of Life Scales (QOLS) (adults only). Independent variables that showed significant results using univariate tests underwent multiple logistic regression analysis.

RESULTS

227 patients were available for analysis. Mean duration of disease at time of assessment of outcome was 15 years (range 5.3-36.1). Univariate tests allowed 11 variables for disability, 9 for pain, 7 for overall well being, and 4 for QOL into the multivariate analysis. The best predictor of higher disability was the articular severity score (odds ratio, OR, 5.69) while antinuclear antibody positivity foretold less disability (OR 0.29). HLA-DR5 positivity conferred the greatest risk for pain (OR 3.34), while HLA-B5, DR3, and C3 were protective (OR 0.25, 0.28, 0.33, respectively). Early hand involvement was the strongest predictor of poorer overall well being (OR 8.75). Only the erythrocyte sedimentation rate was predictive of future QOL, but the model yielded a low C statistic (< 70%) and the OR 95% confidence limits were extreme (OR 9.77; 95% confidence interval, 1.22-77.8).

CONCLUSION

Clinical and immunogenetic variables measurable within 6 months of onset of JRA can be used to predict future disability, pain, and well being. QOL appears more difficult to forecast, perhaps due to the multiple domains that make up this outcome. Further study is needed to identify other genetic and laboratory factors that predict outcome in JRA with greater precision.

Inhibitory control as a contributor to conscience in childhood: from toddler to early school age

In this article we report a longitudinal extension of previous findings about the critical role of temperamental inhibitory or effortful control as the contributor to developing conscience in young children. A comprehensive observational battery, highly internally consistent, was developed to measure inhibitory control in 83 children at early school age who had been followed since toddlerhood and had been assessed using similar batteries at toddler and preschool age. We again confirmed the findings of robust longitudinal stability of inhibitory or effortful control, now from toddler to early school age, the increase with age, and gender differences, with girls outperforming boys. We also reaffirmed strong links, both contemporaneous and in the longitudinal sense, between inhibitory control and multiple, diverse measures of children's conscience at early school age, including observations of moral conduct, moral cognition, and moral self. The findings are discussed in view of the increasingly appreciated importance of temperament for critical aspects of socialization.

Dichloroacetate inhibits glutamine oxidation by decreasing pyruvate availability for transamination

We have shown that dichloroacetate (DCA) inhibits growth, glutamine oxidation, and pyruvate and alanine production in a concentration-dependent manner in PQXB 1/2 hybridoma cells. The use of inhibitors indicates that glutamine oxidation proceeds by an aminooxyacetate-sensitive transamination reaction in this cell line. Addition of pyruvate to DCA-treated cells restored glutamine oxidation to control values. Our data suggest that DCA inhibits glutamine oxidation by decreasing the availability of pyruvate for transamination, which in turn results in glutamate accumulation and a consequent inhibition of glutaminase activity. Impaired glutamine catabolism in the presence of DCA has subsequent effects on overall metabolic balance and cell maintenance and growth.

Mutated epitopes of hepatitis B surface antigen fused to the core antigen of the virus induce antibodies that react with the native surface antigen

Fusion of peptide epitopes to the core antigen (HBcAg) of hepatitis B virus (HBV) enhances their immunogenicity, both quantitatively and qualitatively. In a number of vaccine-induced mutants of HBV, glycine145 of the surface antigen S polypeptide (HBsAg) has been replaced by arginine, resulting in loss of cross-reactivity with antibodies to normal (wild-type) HBsAg. HBcAg fusion proteins carrying the immunodominant epitope of HBsAg, in which glycine145 was replaced by arginine, glutamic acid, or lysine, were produced in Escherichia coli and formed particles that displayed HBc antigenicity and immunogenicity similar to that of HBcAg itself. The fusion proteins also elicited T-cell proliferative responsiveness to HBcAg and HBsAg. Fusions carrying either wild-type or mutated epitopes of HBsAG showed HBs antigenicity in immunoblot analysis and antigen-capture immunoradiometric assay, but both mutant and wild-type derivatives induced antibodies that cross-reacted with wild-type HBsAG. The results emphasise the potential for HBcAg fusion proteins in vaccines by broadening the antibody response in a way that could confer protection against both wild-type and variant form of HBV.

Inadequacies in the Mental Health Act, 1983 in relation to mentally disordered remand prisoners

There are widely recognized problems regarding access to NHS facilities for mentally disordered remand prisoners (Robertson et al., 1994). The Bentham Unit was set up in February 1994 to provide the earliest possible hospital admission for mentally disordered remand prisoners. Over the first twelve months of the service's operation we assessed 150 and admitted 62 remand prisoners: a full description of the service is in preparation. Because admission is restricted to remand prisoners, the inadequacies of current legislation in allowing effective, uninterrupted care for remand transfers have become very apparent. There have been recent proposals to review the 1983 Mental Health Act (Murphy, 1995) and we suggest that provisions for assessment and treatment of mentally disordered remand prisoners should be revised in this context.

Expression of the adrenoleukodystrophy protein in the human and mouse central nervous system

The gene mutated in X-linked adrenoleukodystrophy (ALD), a progressive demyelinating disease, codes for a protein (ALDP) involved in very-long-chain fatty acid (VLCFA) transport. The expression of ALDP and of two peroxisomal enzymes involved in beta-oxidation of VLCFA, acyl-CoA oxidase, and catalase was studied in human and mouse brain. The pattern of expression was similar in both species. While acyl-CoA oxidase and catalase are found in all types of CNS cells, including neurons and oligodendrocytes, ALDP expression is restricted mostly to the white matter and endothelial cells. ALDP is highly expressed in astrocytes and microglial cells in vivo and in regenerating oligodendrocytes in vitro. In contrast, in vivo, ALDP is detected in much fewer oligodendrocytes and quantitative Western blot analysis confirmed the lower abundance of ALDP in these cells than in astrocytes. Only oligodendrocytes localized in corpus callosum, internal capsules, and anterior commissure express ALDP at levels comparable to those seen in astrocytes. In ALD, demyelination is first detected in these white matter regions, suggesting that the ALD gene mutation selectively affects those oligodendrocytes strongly expressing ALDP. Because of their failure to express ALDP, microglia and astrocytes may also contribute to demyelination in ALD patients.

Role of mitomycin in combination with fluorouracil and radiotherapy, and of salvage chemoradiation in the definitive nonsurgical treatment of epidermoid carcinoma of the anal canal: results of a phase III randomized intergroup study

PURPOSE

Definitive chemoradiation (CR) has replaced radical surgery as the preferred treatment of epidermoid carcinoma of the anal canal. To determine the importance of mitomycin (MMC) in the standard CR regimen and to assess the role of salvage CR in patients who have residual tumor following CR, a phase III randomized trial was undertaken by the Radiation Therapy Oncology Group (RTOG)/Eastern Cooperative Oncology Group (ECOG).

PATIENTS AND METHODS

Between August 1988 and December 1991, 310 patients were randomized to receive either radiotherapy (RT) and fluorouracil (5-FU) or radiotherapy, 5-FU, and MMC. Of 291 assessable patients, 145 received 45 to 50.4 Gy of pelvic RT plus 5-FU at 1,000 mg/m2/d for 4 days, and 146 received RT, 5-FU, and MMC (10 mg/m2 per dose for two doses). Patients with residual tumor on posttreatment biopsy were treated with a salvage regimen that consisted of additional pelvic RT (9 Gy), 5-FU, and cisplatin (100 mg/m2).

RESULTS

Posttreatment biopsies were positive in 15% of patients in the 5-FU arm versus 7.7% in the MMC arm (P = .135). At 4 years, colostomy rates were lower (9% v 22%; P = .002), colostomy-free survival higher (71% v 59%; P = .014), and disease-free survival higher (73% v 51%; P = .0003) in the MMC arm. A significant difference in overall survival has not been observed at 4 years. Toxicity was greater in the MMC arm (23% v 7% grade 4 and 5 toxicity; P < or = .001). Of 24 assessable patients who underwent salvage CR, 12 (50%) were rendered disease-free.

CONCLUSION

Despite greater toxicity, the use of MMC in a definitive CR regimen for anal cancer is justified, particularly in patients with large primary tumors. Salvage CR should be attempted in patients with residual disease following definitive CR before resorting to radical surgery.

Unrelated donor bone marrow transplantation to treat severe aplastic anaemia in children and young adults

Alternative donor bone marrow transplantation (BMT) to treat severe aplastic anaemia (SAA) in children and young adults has been complicated by high rates of graft rejection and severe graft-versus-host disease (GVHD). We hypothesized that increased immunosuppression combined with T-cell depletion of the marrow graft would enable successful use of unrelated donor BMT in this disease. Preconditioning consisted of cytosine arabinoside, cyclophosphamide, and total body irradiation (TBI). T-cell depletion was with the anti-CD3 antibody T10B9. GVHD prophylaxis consisted of cyclosporine A. 28 previously transfused patients were transplanted. Nine donor/recipient pairs were HLA matched. As of 1 January 1996, 15/28 (54%) patients are alive, transfusion independent and well with a range of follow-up of 13 months to 8 years (median 2.75 years). Fatalities include all three patients with nonengraftment and all three patients with grade III/IV GVHD. Other fatalities were due to infections or therapy-related toxicity. The incidence >or= grade II acute GVHD was 28%. These data show that in children with SAA who have failed immunosuppression, unrelated donor BMT offers a reasonable hope of long-term survival.

Identification of polyclonal serum specificities with phage-display libraries

A random hexapeptide fusion-phage library was screened to isolate phage that bound antibodies in a serum induced by hepatitis B virus surface antigen (HBsAg). Analysis of the isolated phage and comparison of their displayed peptide sequences with the primary sequence of HBsAg revealed areas where three and four amino acid matches accumulated. Differential binding studies of individual phage clones with immune and pre-immune sera identified phage carrying sequences that matched with region 117-122 of HBsAg which may represent a linear epitope or part of a larger antigenic determinant. Synthetic hexapeptides representing this region competed for binding with the matching phage clones.

Developmental and FGF-2-mediated regulation of syndecans (1-4) and glypican in oligodendrocytes

Differentiating cells undergo developmentally regulated changes in cell-cell and cell-matrix adhesion that control migration through microenvironments, proliferation, and differentiation. The diversity of the patterns of expression of heparan sulfate proteoglycans (HSPGs), coupled with their interactions with extracellular matrix, cell adhesion molecules, and growth factors, has emphasized their critical importance in the regulation of these events. Syndecans (1-4), glypican, and cerebroglycan are membrane-associated HSPGs that have been implicated in these events in various tissues and several tumor cell lines. We have examined the developmental expression and FGF-2-mediated regulation of these HSPGs during differentiation within a specific lineage of primary cells, oligodendrocytes (OL). Northern analyses of highly purified, developmentally synchronized populations of OL-lineage cells at three stages of differentiation (early and late progenitors and mature OLs) showed that the expression of individual forms of these syndecans and glypican are developmentally regulated. Specifically, the level of expression of syndecan-2 and -4 and glypican mRNAs increased as the cells differentiated from proliferative late progenitors to postmitotic mature cells. The expression of syndecan-1 and -3 had the inverse developmental pattern. Therefore, these two sets of molecules may have different roles in regulating the onset of terminal differentiation in OLs. The levels of mRNA expression were regulated by FGF-2: in late progenitors, FGF-2 induced a doubling of the mRNA levels of syndecan-2, -3, and -4, while those for syndecan-1 and glypican remained unaffected; in mature OLs, the levels of syndecan-1 mRNA were up-regulated, the levels of syndecan-2 and -4 and glypican were down-regulated. These results suggest that the individual syndecan molecules have distinct functions during the differentiation process and that multiple levels of regulation must exist, leading to a changing repertoire of these molecules during OL lineage progression and myelinogenesis.

Distal urethral duplication--a case report and literature review

Patient with partial duplication of the distal penile urethra ending blindly in the periurethral tissue, without an external meatus is reported. Relevant literature and the classification of urethral duplication is discussed.

Regulation of FGF receptors in the oligodendrocyte lineage

Fibroblast growth factors (FGFs) affect a broad spectrum of developmentally regulated cellular responses involved in the control of growth and differentiation. To identify specific FGF receptor forms involved in these responses, we have characterized FGF receptor transcript expression, and its modulation by FGF-2, as enriched populations of oligodendrocyte progenitors differentiate into mature oligodendrocytes. The data demonstrate that the levels of mRNA expression for FGF high-affinity receptors-1, -2, and -3 are differentially regulated during lineage progression: FGF receptor-1 expression increases with lineage progression, FGF receptor-2 is predominantly expressed by terminally differentiated oligodendrocytes, and FGF receptor-3 reaches a peak level of expression in late progenitors and then declines upon further differentiation; FGF receptor-4 expression was not detected in oligodendrocytes. Distinct patterns of alternatively spliced variants of FGF receptor-1 and -2 transcripts are expressed: the predominant FGF receptor-1 transcripts contain three Ig-like domains (FGF receptor-1 alpha), whereas the FGF receptor-2 transcripts contain two Ig-like domains (FGF receptor-2 beta 2) and this form is up-regulated as oligodendrocytes differentiate. In addition, the expression of these receptors is differentially regulated by the ligand, FGF-2: FGF receptor-1 mRNA expression is up-regulated in early progenitors, and FGF receptor-2 mRNA expression is down-regulated in mature oligodendrocytes. Finally, astrocytes express FGF receptor-1, -2, and -3 transcripts, but at different levels and with different exon utilization (FGF receptor-1 beta, FGF receptor-2 beta 1/beta 2) compared to oligodendrocytes. To our knowledge this is the first report that demonstrates that the mRNA expression of these three FGF receptor types is differentially regulated in primary cells as they differentiate along a lineage from progenitors to terminally differentiated cells. We propose that this pattern of expression provides a molecular basis for the developmentally varying response of cells to a common ligand. For example, according to this hypothesis, in response to FGF-2, FGF receptor-1 transduces signals that stimulate the prolonged proliferation and migration of early progenitors, FGF receptor-3 promotes the proliferation and arrest of differentiation of late progenitors, and FGF receptor-2 transduces signals for terminal differentiation, but not proliferation, in mature oligodendrocytes.

Inhibitory control in young children and its role in emerging internalization

We examined inhibitory control as a quality of temperament that contributes to internalization. Children were assessed twice, at 26-41 months (N = 103) and at 43-56 months (N = 99), on repeated occasions, in multiple observational contexts and using parental reports. Comprehensive behavioral batteries incorporating multiple tasks were designed to measure inhibitory control at toddler and preschool age. They had good internal consistencies, corresponded with maternal ratings, and were developmentally sensitive. Individual children's performance was significantly correlated across both assessments, indicating stable individual differences. Girls surpassed boys at both ages. Children's internalization was observed while they were alone with prohibited objects, with a mundane chore, playing games that occasioned cheating, being induced to violate standards of conduct, and assessed using maternal reports. Inhibitory control was significantly associated with internalization, both contemporaneously and as a predictor in the longitudinal sense. The implications for considering children's temperament as a significant, yet often neglected contributor to developing internalization are discussed.

Protein B: an important human IgA-binding reagent

Protein B had a much higher affinity for human IgA than Jacalin, increasing the sensitivity and specificity of the measurement of total human IgA. Protein B, used as a capturing agent, greatly enhanced the measurement of antigen-specific IgA as compared to alpha chain-specific antibodies.

IL-12, as an adjuvant, promotes a T helper 1 cell, but does not suppress a T helper 2 cell recall response

IL-12 is a potent inducer of NK and cytolytic T cell activity, IFN-gamma production, and T cell proliferation, and is necessary for differentiation of naive T cells to the Th1 subset. We have previously shown that IL-12 promotes a primary Th1 response and suppresses a primary Th2 response in lymph nodes of mice primed with a model hapten-protein conjugate, 2,4,6-trinitrophenyl (TNP)-keyhole limpet hemocyanin (KLH). We have now extended these studies to determine the Th phenotype of the recall response following immunization with soluble Ag and IL-12. For these experiments, mice were primed with TNP-KLH with or without treatment with IL-12, allowed to progress beyond the primary immune response, and challenged by i.p. injection of TNP-KLH. The phenotype of the recall response was monitored by measuring ex vivo production of IFN-gamma and IL-4 in Ag-stimulated lymph node and spleen cell cultures. Titer and isotype of TNP-specific serum Abs were also evaluated. Mice primed with Ag+IL-12 developed a Th1 recall response, as detected by KLH-specific IFN-gamma production from cultured spleen cells and the presence of TNP-specific IgG2a Ab in serum. However, they also developed an Ag-specific Th2 recall response, as characterized by Ag-induced IL-4 production from spleen cells and the presence of high titers of anti-TNP IgG1 in the serum. Studies of the cytokine profile during the primary response revealed that IL-12 induced in spleen cells the capacity to express both IL-4 and IFN-gamma. CD4+ T cells are necessary for production of IL-4 in the spleens of IL-12-treated mice, and most likely account for the Th2 recall response detected in mice primed with Ag+IL-12. These results indicate that the Th1 phenotype induced by immunization with IL-12 and Ag is maintained so that a Th1 recall response is expressed upon subsequent challenge with Ag. However, immunization with IL-12 also supports the development of a Th2 recall response, indicating that the Th1-inducing effect of IL-12 in vivo is not accompanied by a long lasting suppression of Th2 development.

IL-12, as an adjuvant, promotes a T helper 1 cell, but does not suppress a T helper 2 cell recall response

IL-12 is a potent inducer of NK and cytolytic T cell activity, IFN-gamma production, and T cell proliferation, and is necessary for differentiation of naive T cells to the Th1 subset. We have previously shown that IL-12 promotes a primary Th1 response and suppresses a primary Th2 response in lymph nodes of mice primed with a model hapten-protein conjugate, 2,4,6-trinitrophenyl (TNP)-keyhole limpet hemocyanin (KLH). We have now extended these studies to determine the Th phenotype of the recall response following immunization with soluble Ag and IL-12. For these experiments, mice were primed with TNP-KLH with or without treatment with IL-12, allowed to progress beyond the primary immune response, and challenged by i.p. injection of TNP-KLH. The phenotype of the recall response was monitored by measuring ex vivo production of IFN-gamma and IL-4 in Ag-stimulated lymph node and spleen cell cultures. Titer and isotype of TNP-specific serum Abs were also evaluated. Mice primed with Ag+IL-12 developed a Th1 recall response, as detected by KLH-specific IFN-gamma production from cultured spleen cells and the presence of TNP-specific IgG2a Ab in serum. However, they also developed an Ag-specific Th2 recall response, as characterized by Ag-induced IL-4 production from spleen cells and the presence of high titers of anti-TNP IgG1 in the serum. Studies of the cytokine profile during the primary response revealed that IL-12 induced in spleen cells the capacity to express both IL-4 and IFN-gamma. CD4+ T cells are necessary for production of IL-4 in the spleens of IL-12-treated mice, and most likely account for the Th2 recall response detected in mice primed with Ag+IL-12. These results indicate that the Th1 phenotype induced by immunization with IL-12 and Ag is maintained so that a Th1 recall response is expressed upon subsequent challenge with Ag. However, immunization with IL-12 also supports the development of a Th2 recall response, indicating that the Th1-inducing effect of IL-12 in vivo is not accompanied by a long lasting suppression of Th2 development.

Monoclonal autoantibody SCH94.03, which promotes central nervous system remyelination, recognizes an antigen on the surface of oligodendrocytes

A monoclonal antibody SCH94.03, made in syngeneic mice by injection of spinal cord homogenate, promotes central nervous system remyelination when injected into SJL/J mice chronically infected with Theiler's virus. To elucidate the mechanism of antibody-mediated remyelination, SCH94.03 was investigated by immunocytochemistry, flow cytometry, immunoelectron microscopy, Western blotting, and immuno-thin layer chromatography. All cell types investigated in vitro showed strong cytoplasmic staining with a pattern resembling a cytoskeletal protein. In contrast, among the primary cultured cells studied, only oligodendrocytes showed strong surface reactivity. Other cell types, including astrocytes, microglia, Schwann cells, myoblasts, and T and B lymphocytes, were negative. Mouse and rat oligodendrocytes which showed strong surface reactivity exhibited a well-differentiated morphology, and approximately 50% expressed myelin basic protein. Since oligodendrocyte progenitors were negative for surface staining, the expression of the antigens recognized by this monoclonal antibody appears to be developmentally regulated, i.e., transiently expressed on younger, terminally differentiating oligodendrocytes. Among the cell lines studied, only two rat oligodendrocyte lineage cell lines showed surface reactivity with SCH 94.03. Western blotting of secondary isolated oligodendrocytes lysates revealed reactivity with multiple protein bands of 27, 32, 50, 100, and 106 kDa, whereas there was no reactivity to lipid antigens by immuno-thin layer chromatography. These results raise the possibility that SCH94.03 recognizes a novel oligodendrocyte-specific surface antigen, and may act directly on oligodendrocytes to promote remyelination.

Preirradiation chemotherapy with cyclophosphamide, doxorubicin, vincristine, and dexamethasone for primary CNS lymphomas: initial report of radiation therapy oncology group protocol 88-06

PURPOSE

This study was a prospective phase I/II trial performed by the Radiation Therapy Oncology Group (RTOG) to test the tolerance and efficacy of preirradiation cyclophosphamide, doxorubicin, vincristine, and dexamethasone (CHOD) chemotherapy followed by large-volume, high-dose brain radiation therapy (RT) for patients with primary CNS lymphoma (PCNSL).

PATIENTS AND METHODS

Fifty-four (52 assessable) human immunodeficiency virus (HIV)-negative patients with PCNSL were entered on study and received two (n = 20) or three (n = 32) cycles of CHOD (six patients with positive CSF cytology received intrathecal methotrexate in addition to CHOD). Whole-brain RT to 41.4 Gy and tumor boost to 18 Gy (total dose, 59.4 Gy) followed chemotherapy.

RESULTS

As of July 1994, with a minimum potential follow-up time of 20 months, 12 of 52 assessable patients remain alive without evidence of progression. The median survival time for the entire group is 16.1 months, with a 2-year survival rate of 42%. By univariate analysis, patient age was found to be a significant prognostic factor with respect to survival (P = .005) in favor of age less than 60 years. Karnofsky performance status (KPS) was of borderline significance (P = .057). Survival for patients treated on RTOG 88-06 was compared with that of patients treated on RTOG 83-15, which tested RT alone. No difference in overall survival was found (P = .53). Grade 4 neutropenia developed in 29 of 51 patients during chemotherapy. There were two deaths during chemotherapy: one as a result of sepsis and one of a pulmonary embolus. The worst toxicity during RT was < or = grade 2 in 50 of 52 patients.

CONCLUSION

Preirradiation CHOD chemotherapy does not significantly improve survival over RT alone for patients with PCNSL. Age remains a powerful prognostic factor independent of therapy and must be considered in testing alternative combined approaches.