Robert J. Fallis

Cell-mediated immunity to myelin-associated glycoprotein, proteolipid protein, and myelin basic protein in multiple sclerosis.

Peripheral blood lymphocytes (PBL) from active and stable multiple sclerosis (MS) patients, patients with other neurologic diseases (OND), and control subjects were tested for sensitization to two myelin antigens not previously examined in multiple sclerosis, using a [3H]thymidine incorporation assay. The antigens investigated were myelin-associated glycoprotein (MAG) and proteolipid protein (PLP). In addition, sensitization to myelin basic protein (MBP) was also tested. Lymphocyte stimulation indices in active MS patients that were greater than 2 standard deviations above controls were as follows: 9/30 for MAG, 0/17 for PLP, and 8/81 for MBP. No control subjects responded to MAG or PLP, and only 1/29 control subjects responded to MBP. Three of the patients that responded to MAG also responded to MBP. Although the mean proliferative response to MAG and to MBP was greater in the population of active MS patients than in stable MS, ONDs, or controls, the difference was not statistically significant. The OND group was the only population which proliferated to PLP (6/16). The only statistically significant differences among the groups for all myelin antigens tested were the proportion of individuals with active MS vs. controls that responded to MAG (P less than 0.05), and OND vs. controls and active MS that responded to PLP (P less than 0.025). The greatest individual responses to the three antigens tested were to MBP in active MS patients. Elimination of the T8 (cytotoxic/suppressor) subset amplified the responses to myelin antigens in some patients and ONDs studied. These studies have demonstrated reactivity to MAG but not PLP in some patients with active MS, and reactivity to PLP in some patients with other neurologic diseases.

Immunologic responses of progressive multiple sclerosis patients treated with an anti-T-cell monoclonal antibody. anti-T12

Twelve patients with progressive MS were treated with a murine IgM pan-T-cell monoclonal antibody reactive against T12, a determinant present on most post-thymic T-cells. Circulating T12 + cells could not be detected from days 1 to 7, although T3 + Til + T12 - cells appeared by day 3. Human anti-mouse antibodies were detected in 78% of patients by day 7 and correlated with a decrease in anti-T12 M Ab blood levels and the reappearance of T12 + cells in the blood. Although there were high levels of anti-T12 MAb in the serum, there were only barely detectable levels in the CSF and no decrease in the proportion of T12+ cells in the CSF with treatment. Immunologic studies demonstrated a decrease of in vitro pokeweed mitogen-driven Ig synthesis on day 3 with an increase on day 10 that consisted in part of human anti-mouse antibodies. Eleven of 12 patients completed therapy. Prednisone was administered with the treatment after mild allergic reactions occurred in the first two patients. Because this was an open phase one study and patients were treated with prednisone, the effect of treatment on the progression of disease is difficult to assess, and no definitive conclusions concerning clinical effects can be made.

Cerebral vasculitis and hemorrhage associated with phenylpropanolamine

A 20-year-old woman using an oral diet aid preparation containing phenylpropanolamine presented with an intracerebral hemorrhage and angiographic evidence of cerebral vaculitis. Gas chromatography demonstrated phenylpropanolamine in the urine. Even when used within recommended guidelines, phenylpropanolamine usage should be included in the differential diagnosis of patients presenting with intracranial hemorrhage.

Altered blood T-cell subsets in patients with multiple sclerosis☆

We have found an alteration in T-cell subsets in patients with active multiple sclerosis, specifically an increase in the T4:T8 ratio. These findings have been reproducibly obtained over the past four years, occurring in the majority of acute patients tested early in the course of an attack and in between 25 and 40% of chronic progressive patients, depending on their stage of illness. These changes correlate with pleocytosis in spinal fluid and with other abnormalities of immune function, such as spontaneous immunoglobulin production. They have been helpful in assessing disease activity in patients being treated on a variety of protocols and as part of research studies of immunoregulatory abnormality in multiple sclerosis, but have not been helpful as a diagnostic test for multiple sclerosis. The decrease of these cells in the peripheral blood of patients with active disease may be secondary to migration of these cells to the central nervous system, where they are sequestered.

Adoptive transfer of murine chronic-relapsing autoimmune encephalomyelitis: Analysis of basic protein-reactive cells in lymphoid organs and nervous system of donor and recipient animals

Frequency analysis of myelin basic protein (MBP)-reactive lymphocytes was performed in the chronic relapsing murine experimental allergic encephalomyelitis (EAE) model induced by the adoptive transfer of myelin basic protein (MBP)-primed lymphocytes to naive recipients. During the first attack, MBP-reactive cell frequencies were: 1/41,700 in spleen, 1/328,000 in lymph nodes, 1/64,500 in the peripheral blood. After recovery from a second attack, the frequencies were: 1/11,000 in spleen, 1/46,000 in lymph node, and 1/195,000 in the blood. In addition, lymph node cells obtained from animals following a second attack had increased encephalitogenic properties. CNS-derived lymphocytes analyzed during the first attack were 50% Lyt 1.2+ and 16% Lyt 2.2+. After recovery from the second attack, phenotypes were 20% Lyt 1.2+ and 49% Lyt 2.2+. There were only minimal responses to MBP in CNS-derived lymphocytes. Susceptibility to adoptively transferred EAE was in general predicted by whether a proliferative response to MBP occurred following immunization and was not solely H-2 linked. These studies demonstrate an accumulation of autoreactive cells in the spleen and lymph nodes and a shift of the phenotype of cells in the target organ as EAE becomes chronic and suggest there are dynamic immunologic processes, both in the peripheral immune system and target organ associated with relapsing EAE.

Serial analysis of peripheral blood T‐cell phenotypes and myelin basic protein reactivity in experimental allergic encephalomyelitis

We have serially analyzed peripheral blood T-cell phenotypes and reactivity to myelin basic protein (MBP) during the course of acute experimental allergic encephalomyelitis (EAE) in the Lewis rat and have correlated changes with the onset of clinical disease. A reduction in total T cells (W3/13 +), due primarily to a reduced helper/inducer (W3/25 +) subpopulation, preceded the onset of EAE. Circulating MBP-reactive lymphocytes were only transiently present in the blood at the time EAE was clinically evident. Our findings demonstrate that in EAE, immunologic abnormalities in the peripheral blood are transient and can begin before clinical disease is evident.

Immunoregulatory abnormalities induced by experimental reovirus infection: Functional alterations in T-cell subpopulations

A primary anti-sheep red blood cell (SRBC) plaque assay system was used to analyze the effect of reovirus infection on immunoregulatory T-cells. A decrease in the plaque-forming cell (PFC) response of splenic lymphocytes was observed within 24 hr of infection with 10(9) or 10(11) particles of reovirus type 1 or reovirus type 3 and persisted for more than 7 days. In coculture experiments, T-cells from infected mice were found to produce less help to control B-cells and to suppress helper function mediated by control T-cells. This suppression did not require the presence of an Lyt1,2,3 cell. In addition, isolated Lyt1 cells from reovirus-inoculated mice provided less help than did Lyt1 cells from normal controls. These abnormalities were more marked following inoculation with reovirus type 3 than with type 1. Live virus was not required for these effects, as T-cells from mice inoculated with ultraviolet (uv)-inactivated reovirus when added to normal B-cells reproduced the effects of infection with live virus. Furthermore, these changes were not the result of alterations in the percentages or numbers of distinct Lyt-bearing T-cell subpopulations in the spleens of inoculated mice. Thus, humoral hyporesponsiveness following reovirus infection of adult mice is associated both with active T-cell suppression of B-cell help and with decreased help mediated by the Lyt1 subset.