Treatment of chronic relapsing experimental allergic encephalomyelitis with the intravenous administration of splenocytes coupled to encephalitogenic peptide 91-103 of myelin basic protein

Chronic relapsing experimental allergic encephalomyelitis (CR-EAE) is an autoimmune demyelinating disease of the central nervous system and serves as an experimental model of human multiple sclerosis. Amino acid residues p91-103 of myelin basic protein are encephalitogenic in SJL mice and transfer of T cell lines that recognize this epitope results in CR-EAE. We show here that coculture of T cells in the presence of p91-103 that has been chemically cross-linked to the antigen presenting cells renders the T cell lines tolerant to the antigen. Injection of p91-103 coupled splenocytes into animals that had received encephalitogenic p91-103 reactive T cells significantly reduced the incidence and severity of EAE. Furthermore, treatment of mice with a single injection of antigen coupled splenocytes after they had recovered from their initial paralytic attack prevented the development of subsequent clinical relapses in all animals. These studies indicate that this effect is long lasting and can be successfully accomplished in an established autoimmune disease. Hence this form of immunotherapy may be considered as a therapeutic modality in the treatment of autoimmune diseases when the autoantigens are known.

Successful treatment of experimental allergic encephalomyelitis with transforming growth factor-beta 1

Transforming growth factor-beta 1 (TGF-beta 1) is a multifunctional cytokine with immunosuppressive effects on T cells in vitro. Experimental allergic encephalomyelitis is an archetypal T cell-mediated autoimmune demyelinating disease of the central nervous system that often serves as a model for multiple sclerosis. In vivo administration of TGF-beta 1 into SJL mice was successful in reducing the incidence of clinical disease and the histologic severity of inflammation and demyelination in the brain and spinal cord. Immunohistochemical studies performed on control animals showed that TGF-beta-1, -2, and -3 were present in inflammatory perivascular lesions in the brain. The use of a naturally occurring cytokine with immunoregulatory functions in the treatment of an autoimmune disease is novel. However, potential long term complications of such therapy must be addressed before its use in human autoimmune disease such as multiple sclerosis.

Successful treatment of experimental allergic encephalomyelitis with transforming growth factor-beta 1

Transforming growth factor-beta 1 (TGF-beta 1) is a multifunctional cytokine with immunosuppressive effects on T cells in vitro. Experimental allergic encephalomyelitis is an archetypal T cell-mediated autoimmune demyelinating disease of the central nervous system that often serves as a model for multiple sclerosis. In vivo administration of TGF-beta 1 into SJL mice was successful in reducing the incidence of clinical disease and the histologic severity of inflammation and demyelination in the brain and spinal cord. Immunohistochemical studies performed on control animals showed that TGF-beta-1, -2, and -3 were present in inflammatory perivascular lesions in the brain. The use of a naturally occurring cytokine with immunoregulatory functions in the treatment of an autoimmune disease is novel. However, potential long term complications of such therapy must be addressed before its use in human autoimmune disease such as multiple sclerosis.

In vivo administration of TNF-alpha prevents EMC-M virus induced viral encephalitis

EMC-M virus causes a monophasic paralytic syndrome characterized by encephalitic lesions in the brain and patchy demyelinating lesions in the spinal cord and nerve roots of BALB/c mice. Since the replication of EMC virus in vitro is inhibited by tumor necrosis factor (TNF)-alpha we have studied the effect of in vivo administration of this cytokine on the acute disease. Our studies show that periodic administration of TNF-alpha to animals infected with EMC-M reduces viral titers in the brain, and decreases the degree of clinical paralysis and the severity of the inflammatory lesions in the brain.

Haplotype-specific inhibition of homing of radiolabeled lymphocytes in experimental allergic encephalomyelitis following treatment with anti-IA antibodies

In vivo treatment with anti-IA antibodies has been shown to induce a haplotype-specific inhibition of EAE when the disease was following passive transfer of MBP-sensitized T cells. In order to determine the mechanism by which anti-IA antibody prevents passively transferred EAE, the homing of radiolabeled cells to the brain following anti-IA therapy was studied. Administration of anti-IA antibodies at the earliest onset of clinical signs of EAE prevented the homing of radio-labeled cells to the brain. In F1 (Balb/c x SJL/J) mice that developed EAE and received anti-IAs antibody there was a decreased homing of radiolabeled cells when compared to animals that received anti-IAd antibody. In addition, there was preferential expression of IAs antigen, over IAd antigen on capillary endothelium of the brain. The differential expression of IA antigens and the homing of radiolabeled cells in F1 (SJL x Balb/c) mice could in part explain the haplotype-specific suppression of disease following treatment with anti-IA antibodies.

Indirect role of T cells in development of polioencephalitis and encephalomyelitis induced by encephalomyocarditis virus

Infection of female BALB/c mice with encephalomyocarditis virus results in the development of a paralytic syndrome in 7 to 10 days postinoculation. Previous studies had suggested the involvement of an immune component in the development of central nervous system pathology. We have examined the effects of T-cell depletion on the development of polioencephalitis (neuronal necrosis and inflammation of the brain and brain stem) and the relative contribution of the CD4+ and CD8+ subsets following the establishment of viremia. We show that monoclonal antibody depletion of T cells is effective in the reduction of polioencephalitis when given prior to viral inoculation. However, administration of the antibodies 12 h or more after viral inoculation failed to alter the development of polioencephalitis or encephalomyelitis. We conclude that T cells are involved in the development of central nervous system disease during the initial stages of infection but are not responsible for the later progression of disease.

T cells responsive to myelin basic protein in patients with multiple sclerosis

Gene mutation in vivo in human T lymphocytes appears to occur preferentially in dividing cells. Individuals with multiple sclerosis (MS) are assumed to have one or more populations of diving T cells that are being stimulated by autoantigens. Mutant T cell clones from MS patients were isolated and tested for reactivity to myelin basic protein, an antigen that is thought to participate in the induction of the disease. The hypoxanthine guanine phosphoribosyltransferase (hprt) clonal assay was used to determine mutant frequency values in MS patients with chronic progressive disease. Eleven of 258 thioguanine-resistant (hprt-) T cell clones from five of the six MS patients who were tested proliferated in response to human myelin basic protein without prior in vitro exposure to this antigen. No wild-type clones from these patients, nor any hprt- or wild-type clones from three healthy individuals responded to myelin basic protein. Thus, T cell clones that react with myelin basic protein can be isolated from the peripheral blood of MS patients.

Spontaneous development in vitro of a myelin basic protein-specific suppressor T cell line

T cell lines to myelin basic protein (MBP) developed following in vitro culture cause experimental allergic encephalomyelitis (EAE) upon transfer into naive recipient mice. We have, however, repeatedly observed that MBP-specific T cell lines lose their ability to transfer EAE after 40 days in culture. Analyses of such cell lines failed to show any differences in their proliferative responses to antigen, or in the secretion of interleukin-2 (IL-2) and/or IL-4 when compared to their encephalitogenic counterparts. In contrast, examinations of T cell receptor (TCR) beta-chain gene rearrangement patterns showed sequential changes in the clonal population of cells concomitant with the loss of encephalitogenic function. Furthermore, transfer of a non-encephalitogenic, genotypically altered cell line after long-term in vitro culture into mice challenged with MBP suppressed the development of EAE. These findings suggest that the development of such putative regulatory cells in vivo may be involved in the recovery in EAE.

Treatment of encephalomyocarditis virus-induced central nervous system demyelination with monoclonal anti-T-cell antibodies

Infection of BALB/c mice with the M variant of encephalomyocarditis virus resulted in the development of a paralytic syndrome in 7 to 10 days. The paralysis was maximal during the period of viral clearance; most of the animals recovered from the initial deficit and showed no delayed recurrences. Pathologically, the white matter of brain and spinal cord showed well-demarcated areas of perivascular cuffing, demyelination, and, during recovery, remyelination by oligodendrocytes--all suggestive of postinfectious encephalomyelitis. Depletion of either the CD4 or CD8 subset of T cells in vivo with the appropriate monoclonal antibody, GK1.5 or 2.43, respectively, administered one day (24 h) prior to infection was sufficient to limit the development of the paralytic syndrome by 79% (GK1.5) and 82% (2.43).

Use of a rapid thermal annealing system to initiate indiffusion for fabrication of Ti:LiNbO(3) optical channel waveguides

A rapid thermal annealing (RTA) system has been used to initiate indiffusion of Ti into LiNbO(3) for fabrication of optical channel waveguides. Four separate processes are investigated, each with different RTA temperature vs time variations followed by furnace heating. The sample processed with a fast initial ramp of temperature vs time to 875 degrees C yielded the lowest waveguide propagation loss of 1 dB/cm at a wavelength of 632.8 nm, compared with samples processed with other RTA variations and with a sample undergoing only furnace processing. Use of a dry O(2) ambient during RTA resulted in a smoother waveguide surface with no outdiffusion, when compared with use of a wet O(2) ambient.

Suppression of murine collagen-induced arthritis with monoclonal anti-Ia antibodies and augmentation with IFN-gamma

Collagen-induced arthritis (CIA) is an experimental model in which a specific immune response to type II collagen (CII) is associated with the development of inflammatory arthritis. In this study, we evaluated the effects of early and delayed treatments with anti-Ia mAb and IFN-gamma on murine CIA. Administration of anti-Ia mAb at the time of immunization with CII decreased the incidence and delayed the onset of arthritis, whereas anti-Ia treatments begun 2 wk after immunization had no effect upon either arthritis incidence or onset. Neither treatment protocol resulted in a significant decrease in antibody titer or proliferative response to CII. Because IFN-gamma increases Ia expression in a variety of cells, we determined its effect on arthritis incidence and onset. When IFN-gamma treatments were begun at the time of immunization the incidence of arthritis was increased and arthritis onset was more rapid. Treatment with IFN-gamma did not result in an increase in anti-CII antibody levels. These results support the importance of Ia expression in the induction of murine collagen-induced arthritis, and suggest that suppression with anti-Ia antibodies and augmentation with IFN-gamma are not the result of changes in the humoral response to CII, but may be due to local effects within the target organ.

Suppression of murine collagen-induced arthritis with monoclonal anti-Ia antibodies and augmentation with IFN-gamma

Collagen-induced arthritis (CIA) is an experimental model in which a specific immune response to type II collagen (CII) is associated with the development of inflammatory arthritis. In this study, we evaluated the effects of early and delayed treatments with anti-Ia mAb and IFN-gamma on murine CIA. Administration of anti-Ia mAb at the time of immunization with CII decreased the incidence and delayed the onset of arthritis, whereas anti-Ia treatments begun 2 wk after immunization had no effect upon either arthritis incidence or onset. Neither treatment protocol resulted in a significant decrease in antibody titer or proliferative response to CII. Because IFN-gamma increases Ia expression in a variety of cells, we determined its effect on arthritis incidence and onset. When IFN-gamma treatments were begun at the time of immunization the incidence of arthritis was increased and arthritis onset was more rapid. Treatment with IFN-gamma did not result in an increase in anti-CII antibody levels. These results support the importance of Ia expression in the induction of murine collagen-induced arthritis, and suggest that suppression with anti-Ia antibodies and augmentation with IFN-gamma are not the result of changes in the humoral response to CII, but may be due to local effects within the target organ.

In vivo modulation of murine collagen induced arthritis

The effects of in vivo modulation of murine collagen induced arthritis with monoclonal anti-CD4 antibodies, monoclonal anti-Ia antibodies, and gamma interferon are reviewed. We detail the mechanism of action of monoclonal anti-CD4 antibody on humoral and cell mediated immune responses and discuss the implications for designing therapeutic strategies. To further explore the induction of collagen induced arthritis, a syngeneic cell transfer system using collagen primed T lymphocytes is described. This cell transfer system provides an opportunity to study the role of CD4 positive T lymphocytes in arthritis induction during a short, defined time period.

In vivo immunomodulation by monoclonal anti-CD4 antibody. II. Effect on T cell response to myelin basic protein and experimental allergic encephalomyelitis

In vivo administration of anti-CD4 mAb (GK1.5) has been shown to be effective in preventing acute and relapsing experimental allergic encephalomyelitis (EAE). In the present report we have studied the depletion of CD4+ cells by a single dose of GK1.5 on the immune response to myelin basic protein and in the development of EAE. Our studies show that depletion of CD4 cells in mice that had received encephalitogenic CD4+ T cells altered the kinetics of acute and relapsing EAE, but did not prevent disease altogether. The in vitro T cell proliferative response to myelin basic protein in lymph node cells was maintained in the presence of significant depletion of CD4+ cells. These studies indicate that the population of Ag-reactive cells to be large and relatively refractory to antibody therapy. The implication of these results to therapy of human autoimmune disease is discussed.

In vivo immunomodulation by monoclonal anti-CD4 antibody. II. Effect on T cell response to myelin basic protein and experimental allergic encephalomyelitis

In vivo administration of anti-CD4 mAb (GK1.5) has been shown to be effective in preventing acute and relapsing experimental allergic encephalomyelitis (EAE). In the present report we have studied the depletion of CD4+ cells by a single dose of GK1.5 on the immune response to myelin basic protein and in the development of EAE. Our studies show that depletion of CD4 cells in mice that had received encephalitogenic CD4+ T cells altered the kinetics of acute and relapsing EAE, but did not prevent disease altogether. The in vitro T cell proliferative response to myelin basic protein in lymph node cells was maintained in the presence of significant depletion of CD4+ cells. These studies indicate that the population of Ag-reactive cells to be large and relatively refractory to antibody therapy. The implication of these results to therapy of human autoimmune disease is discussed.

Successful therapy of Theiler's virus-induced demyelination (DA strain) with monoclonal anti-Lyt-2 antibody

The effects of therapy with mAb to T cell subsets were studied in mice with Theiler's murine encephalomyelitis virus-induced demyelination. mAb GK1.5 (directed at class II-restricted T cells) and mAb 2.43 (directed at class I-restricted T cells) depleted the appropriate subset of T cells in lymph nodes, spleens, and peripheral blood for 6 to 8 wk after a single i.p. injection of 1 mg of purified mAb. Early treatment with mAb GK1.5 (days -1, 0, and +1 relative to virus injection) resulted in death, encephalitis, and increased demyelination in the majority of animals tested. Treatment with mAb 2.43 resulted in less meningeal inflammation and fewer demyelinating lesions in the spinal cord, irrespective of whether the mAb was given early or after demyelinating disease was established (days 15, 16, and 17). Beneficial response to mAb therapy did not correlate with titers of virus isolated from the central nervous system or serum. These results indicate an important role of class II-restricted T cells during early disease in preventing overwhelming encephalitis; class I-restricted T cells may be critical during demyelination.

Successful therapy of Theiler's virus-induced demyelination (DA strain) with monoclonal anti-Lyt-2 antibody

The effects of therapy with mAb to T cell subsets were studied in mice with Theiler's murine encephalomyelitis virus-induced demyelination. mAb GK1.5 (directed at class II-restricted T cells) and mAb 2.43 (directed at class I-restricted T cells) depleted the appropriate subset of T cells in lymph nodes, spleens, and peripheral blood for 6 to 8 wk after a single i.p. injection of 1 mg of purified mAb. Early treatment with mAb GK1.5 (days -1, 0, and +1 relative to virus injection) resulted in death, encephalitis, and increased demyelination in the majority of animals tested. Treatment with mAb 2.43 resulted in less meningeal inflammation and fewer demyelinating lesions in the spinal cord, irrespective of whether the mAb was given early or after demyelinating disease was established (days 15, 16, and 17). Beneficial response to mAb therapy did not correlate with titers of virus isolated from the central nervous system or serum. These results indicate an important role of class II-restricted T cells during early disease in preventing overwhelming encephalitis; class I-restricted T cells may be critical during demyelination.

Clonal diversity of myelin basic protein-specific T lymphocytes

A panel of myelin basic protein (MBP)-specific, class II major histocompatibility complex (As)-restricted T-cell clones were established from SJL/J mice. Three clonotypes, based on their responses to guinea pig MBP and its peptide fragments, were observed. Clonotype I cells, represented by clones HS.6, HS.D2, HS.8, HS.E10, and HS.C1, were reactive to the encephalitogenic C-terminal fragment of MBP, amino acid residues 89-169. Clonotype II, represented by clone HS.E3, was reactive to fragments containing residues 43-88, and clones HS.D12 and HS.C7, representing clonotype III cells, responded to the whole molecule only. Three clones from clonotype I were capable of transferring both clinical and histological signs of experimental allergic encephalomyelitis (EAE) into naive mice. Southern blot analysis of T-cell receptor beta-chain genes using J beta 1- and J beta 2-specific probes showed that the rearrangement pattern was unique in each of the clones. These results suggest that the development of EAE may represent an autoaggressive polyclonal T-cell response.

In vivo depletion of Lyt-2 cells fails to alter acute and relapsing EAE

The cellular mechanisms of recovery and relapses in experimental allergic encephalomyelitis (EAE) are not known. In order to determine the role of the suppressor/cytotoxic T lymphocytes (Lyt-2+) in EAE we studied the effect of in vivo depletion of this subset using monoclonal antibodies. Intraperitoneal injection of 1 mg of monoclonal antibody 2.43 resulted in rapid depletion of Lyt-2+ cells from lymph node, spleen and blood. Depletion of this subset had no effect on the kinetics of development, severity, and duration of acute EAE. Furthermore, following recovery from acute EAE administration of 2.43 did not result in development of relapses that were different in onset or severity from control animals. These results suggest that T cells of the Lyt-2 phenotype do not play a significant role in the immunoregulation of EAE.

Haplotype-specific suppression of experimental allergic encephalomyelitis with anti-IA antibodies

Treatment with monoclonal antibodies directed against the IA antigens of the MHC is known to alter the course and prevent a number of experimental autoimmune diseases. To determine whether the treatment in vivo with anti-IA antibodies is haplotype-specific, we studied the development of EAE in F1 (SJL/J X BALB/c) mice following anti-IA antibody therapy. We report that treatment of animals with monoclonal antibody directed against the high responder allele product, I-As, was successful in preventing disease when therapy was begun either at the time of immunization with antigen, or following passive transfer of MBP-sensitized T cells. Therapy with antibody directed to the low responder allele product (I-Ad), while effective when used at the time of immunization with antigen, was ineffective following passive transfer of MBP-sensitized lymphocytes.

Haplotype-specific suppression of experimental allergic encephalomyelitis with anti-IA antibodies

Treatment with monoclonal antibodies directed against the IA antigens of the MHC is known to alter the course and prevent a number of experimental autoimmune diseases. To determine whether the treatment in vivo with anti-IA antibodies is haplotype-specific, we studied the development of EAE in F1 (SJL/J X BALB/c) mice following anti-IA antibody therapy. We report that treatment of animals with monoclonal antibody directed against the high responder allele product, I-As, was successful in preventing disease when therapy was begun either at the time of immunization with antigen, or following passive transfer of MBP-sensitized T cells. Therapy with antibody directed to the low responder allele product (I-Ad), while effective when used at the time of immunization with antigen, was ineffective following passive transfer of MBP-sensitized lymphocytes.

In vivo immunomodulation by monoclonal anti-L3T4. 1. Effects on humoral and cell-mediated immune response

The in vivo administration of monoclonal anti-L3T4 antibody has been shown to be an effective preventative and, in some cases, therapeutic treatment for several murine models of autoimmune disease. This report deals with the effect of such treatments on humoral and cell-mediated responses to T-dependent antigens. Both the primary and secondary IgG responses to tetanus toxoid were inhibited when anti-L3T4 was administered prior to immunization, but it was ineffective in modulating an ongoing IgG response. Cell-mediated immunity, as detected by in vitro antigen-specific proliferative responses, was inhibited only if anti-L3T4 was given prior to immunization. It was not effective if treatment was delayed until 48 hr prior to lymph node harvest even though greater than 90% of L3T4+ lymph node cells were depleted by this treatment. The refractory behavior of the lymph node cells to anti-L3T4 treatment was not exhibited by antigen-primed cells obtained from peripheral blood or spleen. The importance of these findings with regard to antibody therapy for chronic autoimmune disease is discussed.

Treatment of established chronic relapsing experimental allergic encephalomyelitis with anti-L3T4 antibodies

CR-EAE is an autoimmune T cell-mediated disease that can be induced in mice either by the injection of MSCH and CFA or by passive transfer of MBP-sensitized T cells. To evaluate the clinical relevance of anti-L3T4 antibodies in this relapsing, remitting disease, we studied the therapeutic benefits of such treatment on CR-EAE in animals when treatment was begun after the onset of initial paralytic signs. Animals treated biweekly with anti-L3T4 antibody had fewer relapses than control animals, and the histopathology of the brain and spinal cord showed fewer and less extensive lesions. Serial analysis of lymph node cell populations and antibody levels showed that animals treated with anti-L3T4 antibody had a depletion of the helper/inducer T cell population and did not develop a humoral response to the administered rat antibody. This study raises the possibility of treatment with antibodies against T cell subsets in established disease wherein this subset is known to play a crucial role.

Treatment of established chronic relapsing experimental allergic encephalomyelitis with anti-L3T4 antibodies

CR-EAE is an autoimmune T cell-mediated disease that can be induced in mice either by the injection of MSCH and CFA or by passive transfer of MBP-sensitized T cells. To evaluate the clinical relevance of anti-L3T4 antibodies in this relapsing, remitting disease, we studied the therapeutic benefits of such treatment on CR-EAE in animals when treatment was begun after the onset of initial paralytic signs. Animals treated biweekly with anti-L3T4 antibody had fewer relapses than control animals, and the histopathology of the brain and spinal cord showed fewer and less extensive lesions. Serial analysis of lymph node cell populations and antibody levels showed that animals treated with anti-L3T4 antibody had a depletion of the helper/inducer T cell population and did not develop a humoral response to the administered rat antibody. This study raises the possibility of treatment with antibodies against T cell subsets in established disease wherein this subset is known to play a crucial role.

NK cell function in a patient with IgM monoclonal antibody against myelin-associated glycoprotein

Anti-Leu 7 antibody reacts with determinants on a subset of natural killer (NK) cells and myelin-associated glycoprotein (MAG). In a patient patient with peripheral neuropathy and IgM autoantibodies against MAG, we found the distribution and functions of NK cells to be normal.

Prevention of type II collagen-induced arthritis by in vivo treatment with anti-L3T4

The effect of in vivo administration of monoclonal anti-L3T4 antibody on the development of murine collagen-induced arthritis (CIA) was assessed. Treatment with anti-L3T4 resulted in a greater than 90% depletion of L3T4+ T cells in lymph nodes and spleen, an effect that appears entirely reversed 30 d after treatment. Administration of anti-L3T4 before immunization with type II collagen resulted in a significant decrease in arthritis incidence and delayed onset of the disease while treatment begun after a strong anticollagen IgG humoral response was underway was not effective in altering disease expression. These results suggest a prominent role for L3T4+ T cells in the pathogenesis of CIA.

Characterization of T cell lines and clones from SJL/J and (BALB/c x SJL/J)F1 mice specific for myelin basic protein

Lines of thymus-derived lymphocytes reactive against bovine myelin basic protein (BP) were established in vitro from SJL/J mice. These lines are stable in long-term culture and mediate inflammatory central nervous system (CNS) lesions and a low incidence of clinical experimental allergic encephalomyelitis (EAE) when injected into recipient SJL/J mice. The line cells proliferate in response to BP of bovine, rat, or mouse origin. Clones were derived from these lines, and the characteristics of these clones were analyzed. The clones express Thy-1, Ly-1, and L3T4 antigens and are negative for Ly-T2. The clones all proliferate in response to bovine BP, with different clones showing varying degrees of cross-reactivity between bovine, rat, and mouse BP. The proliferative response is MHC-restricted; antigen-presenting cells from I-As strains are required. Compatible with their phenotype as helper cells, some of the clones will provide help to primed B cells stimulating antibody production in an in vitro assay. When injected into recipients pretreated with pertussis and irradiation, clones that showed proliferation to mouse BP induced the development of inflammatory lesions in the CNS, with mortality of 28% of the recipients. T cell lines were also established in (BALB/c x SJL/J)F1 mice. In contrast to the homozygous SJL/J lines, these lines were highly encephalitogenic, inducing a high incidence of clinical and histologic EAE when injected in vivo.

Characterization of T cell lines and clones from SJL/J and (BALB/c x SJL/J)F1 mice specific for myelin basic protein

Lines of thymus-derived lymphocytes reactive against bovine myelin basic protein (BP) were established in vitro from SJL/J mice. These lines are stable in long-term culture and mediate inflammatory central nervous system (CNS) lesions and a low incidence of clinical experimental allergic encephalomyelitis (EAE) when injected into recipient SJL/J mice. The line cells proliferate in response to BP of bovine, rat, or mouse origin. Clones were derived from these lines, and the characteristics of these clones were analyzed. The clones express Thy-1, Ly-1, and L3T4 antigens and are negative for Ly-T2. The clones all proliferate in response to bovine BP, with different clones showing varying degrees of cross-reactivity between bovine, rat, and mouse BP. The proliferative response is MHC-restricted; antigen-presenting cells from I-As strains are required. Compatible with their phenotype as helper cells, some of the clones will provide help to primed B cells stimulating antibody production in an in vitro assay. When injected into recipients pretreated with pertussis and irradiation, clones that showed proliferation to mouse BP induced the development of inflammatory lesions in the CNS, with mortality of 28% of the recipients. T cell lines were also established in (BALB/c x SJL/J)F1 mice. In contrast to the homozygous SJL/J lines, these lines were highly encephalitogenic, inducing a high incidence of clinical and histologic EAE when injected in vivo.

HLA-DR antigens in multiple sclerosis: two-dimensional gel electrophoresis

Fifty to eighty percent of white patients with clinically definite MS express the DR2 antigen. In patients and normal controls who possess the DR2 antigens, analysis of the polymorphic light chain by two-dimensional polyacrylamide gel electrophoresis revealed no structural differences.

Reversal of experimental allergic encephalomyelitis with monoclonal antibody to a T-cell subset marker

Administration of a monoclonal antibody (GK1.5) that recognizes the L3T4 marker present on helper T cells prevented the development of experimental allergic encephalomyelitis (EAE) in mice. Furthermore, treatment with GK1.5 reversed EAE when the antibody was given to paralyzed animals. In vivo injection of GK1.5 selectively reduced the number of L3T4+ cells in the spleen and the lymph nodes. These results suggest that manipulation of the human equivalent of the murine L3T4+ T-cell subset with monoclonal antibodies may provide effective therapy for certain autoimmune diseases.

Postinfectious and postvaccinial encephalomyelitis

Addressed are the features of postviral and postvaccinial syndromes affecting the CNS. The relationships among acute disseminated encephalomyelitis, EAE, and MS are discussed. Among the postvaccination syndromes covered are the neurologic sequelae of pertussis immunizations, with a description of a mouse model of this encephalopathy.

Anti I-A antibody suppresses active encephalomyelitis: treatment model for diseases linked to IR genes

To test the clinical relevance of monoclonal anti-I-A antibody in autoimmune disease, we investigated the effects of such a therapy in acute and chronic relapsing experimental allergic encephalomyelitis (EAE) by instituting treatment after the onset of paralytic signs and following the clinical course. In chronic relapsing EAE, animals treated with anti-I-As antibody had no mortality and fewer relapses when compared with control animals. Antibody levels to myelin basic protein were lower and histopathology showed milder lesions in the treated group. Similarly, in the acute EAE model, animals treated with anti-I-As antibody showed a dramatic reversal of paralytic signs and a rapid recovery. The mechanisms of action of antibody to IR gene products in autoimmune disease are discussed.

Prevention of experimental allergic encephalitis with in vivo administration of anti I-A antibody. Decreased accumulation of radiolabelled lymph node cells in the central nervous system

Experimental allergic encephalitis (EAE) can be prevented with the in vivo administration of monoclonal anti I-A antibody. A radiometric assay was developed to measure the accumulation of lymphocytes in the central nervous system of EAE animals. A direct correlation was observed between severity of clinical disease and the amount of radiolabelled lymph node cells (LNC) in the central nervous system. Injection of anti I-A antibody in vivo prevented clinical EAE and decreased the accumulation of radiolabelled LNC in spinal cord after immunization with mouse spinal cord homogenate and adjuvants.

In vivo therapy with monoclonal anti-I-A antibody suppresses immune responses to acetylcholine receptor

A monoclonal antibody to I-A gene products of the immune response gene complex attenuates both humoral and cellular responses to acetylcholine receptor and appears to suppress clinical manifestations of experimental autoimmune myasthenia gravis. This demonstrates that use of antibodies against immune response gene products that are associated with susceptibility to disease may be feasible for therapy in autoimmune conditions such as myasthenia gravis.

Administration of myelin basic protein-coupled spleen cells prevents experimental allergic encephalitis

Intravenous administration of mouse myelin basic protein covalently coupled with chromic chloride to syngeneic spleen cells (MBP-SC) prevents the subsequent induction of experimental allergic encephalitis (EAE). Whereas 1 in 28 mice receiving MBP-SC developed EAE after immunization with mouse spinal cord homogenate (MSCH) and adjuvants, 16 out of 25 mice receiving ovalbumin-coupled spleen cells (OA-SC) had EAE following encephalitogenic challenge. The effect of administration of antigen-coupled spleen cells on in vitro proliferation responses is shown.

Identification of T cell subsets and B lymphocytes in mouse brain experimental allergic encephalitis lesions

Tissue section immunoperoxidase staining, employing monoclonal antibodies specific for T cell antigens (Lyt-1, Lyt-2) and B cells (B220), was used to study the brains of mice with experimental allergic encephalitis. Cells bearing phenotypes characteristic of both helper (Lyt-1+2-) and cytotoxic/suppressor (or precursor) (Lyt-2+) T cells, as well as B cells, are present in the perivascular cuffs in brains of EAE mice during active disease and the recovery phase. Lyt-1+ cells comprise 49% of the inflammatory cell population, and Lyt-2+ and B220+ cells are found at frequencies of 10% and 12%, respectively.

Identification of T cell subsets and B lymphocytes in mouse brain experimental allergic encephalitis lesions

Tissue section immunoperoxidase staining, employing monoclonal antibodies specific for T cell antigens (Lyt-1, Lyt-2) and B cells (B220), was used to study the brains of mice with experimental allergic encephalitis. Cells bearing phenotypes characteristic of both helper (Lyt-1+2-) and cytotoxic/suppressor (or precursor) (Lyt-2+) T cells, as well as B cells, are present in the perivascular cuffs in brains of EAE mice during active disease and the recovery phase. Lyt-1+ cells comprise 49% of the inflammatory cell population, and Lyt-2+ and B220+ cells are found at frequencies of 10% and 12%, respectively.

In vivo effects of antibodies to immune response gene products: prevention of experimental allergic encephalitis

Prevention of experimental allergic encephalitis in SJL/J [H-2s] mice was achieved with in vivo administration of antibody reactive with I-As gene products prior to immunization with spinal cord antigen. No protection was evident in animals that received antisera specific for I-Js gene products. Administration of antibody to I-As beginning 5 days after immunization with spinal cord antigen delayed, but did not prevent, the onset of experimental allergic encephalitis.

Chronic neuropathy presenting as a floppy infant with respiratory distress

Respiratory distress was the presenting feature in a 4-month-old male infant suffering from Déjérine-Sottas disease, an inherited sensory-motor polyneuropathy. This unusual but potentially benign disorder can be diagnosed upon peripheral nerve biopsy by noting extensive demyelination with "onion bulb" formation. Polyneuropathy should be considered in the differential diagnosis of infantile neuromuscular weakness including or solely involving bulbar and respiratory muscles.

Optical coupling from fibers to channel waveguides formed on silicon

Direct coupling of light from fibers supported in preferentially etched grooves on a silicon surface to channel waveguides formed in the same grooves is demonstrated. Criteria are presented for choosing a groove geometry that matches the center of the fiber to the center of the waveguide and thereby yielding optimum coupling. Channel waveguide tapering and integration of detectors into the channel waveguide termination are demonstrated. A general configuration allowing CCD time multiplexing is introduced.