Glatiramer acetate-specific antibody titres in patients with relapsing / remitting multiple sclerosis and in experimental autoimmune encephalomyelitis.

Glatiramer acetate (GA) is an immunomodulatory drug approved for the treatment of clinically isolated syndrome (CIS) and relapsing/remitting multiple sclerosis (RRMS). As an antigen-based therapy, GA induces GA-specific antibodies in treated patients and animals. GA-specific antibodies do not neutralize therapeutic effects on relapses and disability. Rather, it has been suggested that GA-specific antibodies may be associated with improved clinical outcomes. We evaluated antibody responses in eight patients with RRMS treated with GA for 15 months and antibody responses in GA-treated C57BL/6 mice before and after induction of experimental autoimmune encephalomyelitis (EAE). There were no significant differences from pretreatment levels of total IgE or GA-specific IgE in patients with RRMS. Total IgG1, IgG3 and GA-specific IgG4 were significantly increased at 15 months of GA treatment. Antibody type and titre were not associated with clinical outcomes, i.e. expanded disability status scale (EDSS) score, disease burden on magnetic resonance images (MRI) or clinical relapses. In contrast, mice with EAE showed a marked increase in GA-specific IgE and GA-specific IgG1 antibody responses. GA-treated mice demonstrated improved clinical symptoms and lower mortality than untreated controls. Our results suggest that antibody responses to GA are heterogeneous among patients with RRMS, with no apparent association between antibody response and clinical outcomes. Clinical improvements in EAE-induced GA-treated mice suggest that GA-specific IgE and IgG1 may contribute to GA treatment effects in EAE.

Age-related endothelial dysfunction in human skeletal muscle feed arteries: the role of free radicals derived from mitochondria in the vasculature.

AIM: This study sought to determine the role of free radicals derived from mitochondria in the vasculature in the recognized age-related endothelial dysfunction of human skeletal muscle feed arteries (SMFAs). METHODS: A total of 44 SMFAs were studied with and without acute exposure to the mitochondria-targeted antioxidant MitoQ and nitric oxide synthase (NOS) blockade. The relative abundance of proteins from the electron transport chain, phosphorylated (p-) to endothelial (e) NOS ratio, manganese superoxide dismutase (MnSOD) and the mitochondria-derived superoxide (O2-) levels were assessed in SMFA. Endothelium-dependent and endothelium-independent SMFA vasodilation was assessed in response to flow-induced shear stress, acetylcholine (ACh) and sodium nitroprusside (SNP). RESULTS: MitoQ restored endothelium-dependent vasodilation in the old to that of the young when stimulated by both flow (young: 68 ± 5; old: 25 ± 7; old + MitoQ 65 ± 9%) and ACh (young: 97 ± 4; old: 59 ± 10; old + MitoQ: 98 ± 5%), but did not alter the initially uncompromised, endothelium-independent vasodilation (SNP). Compared to the young, MitoQ in the old diminished the initially elevated mitochondria-derived O2- levels and appeared to attenuate the breakdown of MnSOD. Furthermore, MitoQ increased the ratio of p-eNOS to NOS and the restoration of endothelium-dependent vasodilation in the old by MitoQ was ablated by NOS blockade. CONCLUSION: This study demonstrated that MitoQ reverses age-related vascular dysfunction by what appears to be an NO-dependent mechanism in human SMFAs. These findings suggest that mitochondria-targeted antioxidants may have utility in terms of counteracting the attenuated blood flow and vascular dysfunction associated with advancing age.

T-cells for tumor therapy can be obtained from antigen-loaded sponge implants.

The aim of the current study was to evaluate the therapeutic use of tumor-specific T-cells obtained from s.c. Ag (antigen)-loaded sponge implants. Naive C57BL/6 mice were implanted with small, polyurethane sponges containing irradiated FBL-3 tumor cells. On day 10, cells that had accumulated in the sponges were harvested and tested for specific cytolytic and proliferative function in vitro. The results demonstrated that CD8+ and CD4+ T-cells immune to FBL-3 could both be primed in and obtained from the Ag-loaded sponge implants. Limiting dilution analysis demonstrated that the frequency of FBL-3-specific cytotoxic T-lymphocytes elicited from Ag-loaded sponges was four times greater than the frequency from draining lymph nodes and at least 50 times greater than from spleen and peripheral blood. Tumor-specific T-cells could similarly be obtained from Ag-loaded sponges implanted into previously primed mice and into mice bearing disseminated FBL-3. In both circumstances, elicited T-cells exhibited much higher cytolytic activity than T-cells from sponges implanted in naive mice, indicating an in situ accumulation and expansion of primed T-cells in response to the antigen stimulation. Tumor-specific T-cells obtained from Ag-loaded sponge implants could be grown long-term in vitro by periodic restimulation with irradiated FBL-3 and low concentrations of interleukin 2. Adoptive transfer of the resultant expanded T-cell lines into mice with disseminated FBL-3 revealed that cultured sponge-infiltrating T-cells could mediate effective antitumor therapy. Thus, in vivo immunization with Ag-loaded sponges provides a potentially useful technique for procuring primed, Ag-specific T-cells for tumor therapy.

Exacerbation of collagen-induced arthritis in rats by rat cytomegalovirus is antigen-specific.

Collagen-Induced Arthritis (CIA) is an experimentally induced and genetically controlled animal model of chronic joint inflammation. In rats, there are informative strain differences in susceptibility to CIA. DA rats (RT1avl) develop severe CIA after immunization with bovine (BII), chick (CII), or homologous rat (RII) type II collagens. In contrast, the MHC-congenic DA. 1N(BN) and WF.1N(BN) rats (RT1n) are relatively resistant to CIA and develop moderate CIA in response to immunization with CII but not BII or RII. We previously found that simultaneous infection with rat cytomegalovirus (RCMV) greatly exacerbates the severity of arthritis that develops in BII-immunized DA rats. To examine the mechanism of RCMV amplification of CIA, the effect of simultaneous infection with RCMV on arthritis and autoimmunity to type II collagen was determined in WF.1N and DA.1N rats after immunization with BII, CII and RII. RCMV increased the incidence of CIA and the level of autoimmunity to type II collagen (skin-testing and IgG antibody titer) selectively in DA.1N and WF.1N rats immunized with CII, but not in littermates immunized with BII, although the transient reversal of CD4+/CD8+ mononuclear cell ratios in peripheral blood that is associated with RCMV infection occurred equally in both BII- and CII- immunized DA.1N rats. Likewise, RCMV infection moderately increased the levels of anti-RII autoimmunity and arthritis in DA rats sub-optimally immunized with RII but had no consistent effect on either anti-RII immunity or arthritis in RII-immunized DA.1N and WF.1n rats. The data show that RCMV augments arthritis only in rats that are genetically susceptible to CIA and that are appropriately immunized with a species of type II collagen that is arthritogenic for the MHC-haplotype being tested. Two possible mechanisms are suggested by these data: RCMV-associated increases in anti-RII autoimmunity in rats with CIA may result from amino acid sequence homologies between RCMV and type II collagen; alternatively, virus-induced pro-inflammatory cytokines may activate RII-reactive lymphocytes thereby potentiating autoimmunity and arthritis.

PHACE syndrome. The association of posterior fossa brain malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities.

BACKGROUND: Large facial hemangiomas can have associated central nervous system malformations, particularly the Dandy-Walker posterior fossa malformations. Abnormal arteries, especially those of the central nervous system, coarctation of the aorta, cardiac defects, and unusual ophthalmologic abnormalities can also occur. OBSERVATIONS: We describe two patients with large facial hemangioma, congenital cataracts, and structural arterial abnormalities, particularly of the central nervous system vasculature. One of these infants also had a Dandy-Walker malformation detected on prenatal ultrasound at 12 weeks' gestation, suggesting that this syndrome had its origin during the first trimester of pregnancy. This infant also had a lingual thyroid and developed symptomatic hypothyroidism, possible induced by interferon alfa therapy of her hemangioma. These cases are discussed, along with 41 previously reported cases with similar findings. CONCLUSIONS: Large facial hemangiomas may have a distinctive group of associated arterial, central nervous system, and ophthalmologic anomalies. We propose the acronym PHACE syndrome to emphasize the characteristic findings of this neurocutaneous syndrome: posterior fossa malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities.

Crohn's disease in black patients.

Crohn's disease is less prevalent in blacks than in whites. However, when it does occur, it is associated with a high degree of morbidity and is frequently unrecognized at initial presentation. Forty-three patients with Crohn's disease presented to Howard University Hospital between 1965 and 1987. There were 156 hospital admissions, 47 emergency room visits, and 76 clinic visits over this 22-year period. Twenty-eight patients were female and 15 were male. The age of presentation for males ranged from 18 to 63 years and for females, 12 to 74 years. Crohn's disease should be considered in black patients who present with chronic abdominal pain and diarrhea. With correct diagnosis and appropriate medical therapy, patients should have an enhanced quality of life with less morbidity.

Dermatology in the cinema.

The depiction of skin disease in the cinema can be divided into three categories. These include skin findings on actors independent of the roles they portray, cutaneous disease used as a representation of evil, and skin disease represented realistically and sympathetically. Examples from a wide range of films are given, and implications for dermatologists and their patients are discussed.

Adoptively transferred antigen-specific T cells can be grown and maintained in large numbers in vivo for extended periods of time by intermittent restimulation with specific antigen plus IL-2.

The aim of the current study was to determine whether cultured tumor Ag-specific T cells could be induced to grow and maintained functional in large numbers in vivo by intermittent restimulation in vivo with specific Ag plus IL-2. T cells derived from spleens of B6 mice (Thy-1.2) immune to FBL-3, a Friend virus-induced leukemia, were activated by in vitro stimulation with irradiated FBL-3 and expanded by culture for 14 days with low concentrations of IL-2. The resultant FBL-3-specific T cell lines were adoptively transferred into cyclophosphamide pretreated congenic hosts (B6/Thy-1.1), and restimulated every 14 days by an injection of irradiated FBL-3 plus a 7-day course of IL-2. Donor T cells residing in the host were identified and quantified by use of antibody to the Thy-1.2 allele. The results confirmed that stimulation with FBL-3 on the day of transfer (day 0) plus IL-2 on days 0 to 6 induced rapid growth of donor T cells to approximately an 11-fold increase in total donor T cell number recoverable from host ascites and spleen by day 7. However, prolonging the course of IL-2 administration to 35 days did not maintain the number or the specific cytolytic function of donor T cells. By contrast, intermittent restimulation with specific Ag plus IL-2 induced intermittent regrowth of donor T cells in vivo, maintained the number of donor T cells in vivo at greater than the number input for longer than 1 mo, and allowed detection of substantially augmented donor T cell-mediated specific antitumor function over that period of time.

Immunity to WT1 in the animal model and in patients with acute myeloid leukemia.

The Wilms' tumor (WT1) gene participates in leukemogenesis and is overexpressed in most types of leukemia in humans. WT1 is also detectable in many types of lung, thyroid, breast, testicular, and ovarian cancers and melanoma in humans. Initial studies evaluated whether immune responses to murine WT1 can be elicited in mice. Murine and human WT1 are similar. Thus, mouse models might lead to resolution of many of the critical issues for developing WT1 vaccines. C57/BL6 (B6) mice were injected with synthetic peptides from the natural sequence of WT1 containing motifs for binding to major histocompatibility (MHC) class II molecules. Immunization induced helper T-cell responses specific for the immunizing WT1 peptides and antibody responses specific for WT1 protein. Screening of multiple murine cancer cell lines identified 2 murine cancers, TRAMP-C and BLKSV40, that "naturally" overexpress WT1. Immunization with MHC class I binding peptides induced WT1 peptide-specific cytotoxic T-lymphocyte (CTL) that specifically lysed TRAMP-C and BLKSV40. WT1 specificity of lysis was confirmed by cold target inhibition. No toxicity was noted by histopathologic evaluation in the WT1 peptide-immunized animals. WT1 peptide immunization did not show any effect on TRAMP-C tumor growth in vivo. Immunization of B6 mice to syngeneic TRAMP-C elicited WT1-specific antibody, demonstrating that WT1 can be immunogenic in the context of cancer cells. To evaluate whether WT1 might be similarly immunogenic in humans, serum from patients with leukemia was evaluated for pre-existing antibody responses. Western blot analyses showed WT1-specific antibodies directed against the N-terminus portion of the WT1 protein in the sera of 3 of 18 patients with acute myeloid leukemia (AML). (Blood. 2000;96:1480-1489)

Induction of autoimmune arthritis in rats by immunization with homologous rat type II collagen is restricted to the RT1av1 haplotype.

OBJECTIVE: To test for genetic differences in susceptibility to homologous (rat) type II collagen-induced arthritis (RII-CIA). METHODS: Nine inbred and RT1-congenic rat strains were immunized with native rat type II collagen and evaluated for arthritis and IgG anti-RII serum antibody titers. RESULTS: Only RT1av1 strains developed a high incidence of severe RII-CIA and high titers of IgG anti-RII serum antibody. Rats having RII-CIA-resistant haplotypes, RT1u,n,l (which are known to develop CIA after immunization with heterologous type II collagen), were shown to also be susceptible to passive transfer of CIA with immune serum concentrates. Clinical expression of RII-CIA was down-regulated by non-RT1 genes of BN origin. No strong gender differences in anti-RII autoimmune responses were observed. CONCLUSION: Arthritogenic, autoimmune reactivity to homologous RII is under strict genetic control but occurs readily in RT1av1 rats.

CTLs specific for bcr-abl joining region segment peptides fail to lyse leukemia cells expressing p210 bcr-abl protein.

The aim of the current study was to determine whether immunization with synthetic peptides corresponding to the joining region segment of p210 bcr-abl chimeric protein can elicit CD8+ cytotoxic T lymphocytes (CTLs) capable of specifically lysing leukemia cells. BALB/c mice were immunized with peptides identical to the joining region segment of p210 bcr-abl protein. Class I major histocompatibility complex (MHC)-restricted bcr-abl peptide-specific CD8+ CTLs were elicited. The CTL clones were H-2 Kd restricted and specifically recognized a nonamer peptide of the combined sequence of bcr-abl amino acids but neither bcr nor abl amino acid sequence alone. Despite specificity and substantial lytic potential against syngeneic cell line incubated with exogenously supplied peptides, the bcr-abl peptide-specific CTLs failed to lyse syngeneic murine leukemia cells expressing human p210 bcr-abl protein containing the same bcr-abl joining region peptide sequence. Similarly, the bcr-abl peptide-specific CTLs did not lyse human bcr-abl-positive chronic myelogenous leukemia cells expressing murine class I MHC antigen (i.e., K562 cells infected with vaccinia virus expressing H-2 Kd). The appropriateness of the joining region segment of bcr-abl protein to serve as a T cell target depends upon whether that segment is presented by class I MHC in a concentration high enough to stimulate CTLs. The current experiments using murine peptide-specific CTLs could not establish that the joining region of bcr-abl protein is processed and presented by class I MHC antigen-processing pathway, but the possibility was not ruled out. Alternative models and/or strategies are necessary.

The Escherichia coli GTPase CgtAE cofractionates with the 50S ribosomal subunit and interacts with SpoT, a ppGpp synthetase/hydrolase.

CgtA(E)/Obg(E)/YhbZ is an Escherichia coli guanine nucleotide binding protein of the Obg/GTP1 subfamily whose members have been implicated in a number of cellular functions including GTP-GDP sensing, sporulation initiation, and translation. Here we describe a kinetic analysis of CgtA(E) with guanine nucleotides and show that its properties are similar to those of the Caulobacter crescentus homolog CgtA(C). CgtA(E) binds both GTP and GDP with moderate affinity, shows high guanine nucleotide exchange rate constants for both nucleotides, and has a relatively low GTP hydrolysis rate. We show that CgtA(E) is associated predominantly with the 50S ribosomal subunit. Interestingly, CgtA(E) copurifies with SpoT, a ribosome-associated ppGpp hydrolase/synthetase involved in the stress response. The interaction between CgtA(E) and SpoT was confirmed by reciprocal coprecipitation experiments and by two-hybrid assays. These studies raise the possibility that the ribosome-associated CgtA(E) is involved in the SpoT-mediated stress response.

Association of facial hemangiomas with Dandy-Walker and other posterior fossa malformations.

Cutaneous hemangiomas are common benign tumors of infancy that only rarely are associated with malformations in other tissues or organs. We report nine infants with large facial hemangiomas who also had Dandy-Walker malformations or similar posterior fossa abnormalities. On the basis of the experience with our patients and with those previously reported, we recommend radiographic imaging studies of the brain of infants with large, aggressive facial hemangiomas to rule out posterior fossa defects.

Localization of quantitative trait loci regulating adjuvant-induced arthritis in rats: evidence for genetic factors common to multiple autoimmune diseases.

Adjuvant-induced arthritis (AIA) in rats is a widely used autoimmune experimental model with many features similar to rheumatoid arthritis (RA). To identify potential genetic regulatory mechanisms in RA, we conducted genome-wide linkage analysis in F2 progeny of arthritis-susceptible Dark Agouti (DA) and relatively resistant Fischer 344 (F344) inbred rats. We compared the data with our previously reported investigation of collagen-induced arthritis (CIA), which was expanded in the follow-up study reported in this work. We found two quantitative trait loci (QTLs) in common, i.e., Aia1/Cia1 on chromosome 20, which includes the MHC, and Aia3/Cia3 on chromosome 4. We also identified a second unique QTL in AIA, Aia2, on chromosome 4. Interestingly, the QTL region on chromosome 4 (Aia3/Cia3), like the MHC, appears to be involved in several other autoimmune diseases in rats, including insulin-dependent diabetes, thyroiditis, and experimental autoimmune uveitis. Moreover, an analysis of conserved synteny among rats, mice, and humans suggested that Aia2 and Aia3/Cia3, like Aia1/Cia1, contain candidate genes for several autoimmune/inflammatory diseases in mice and humans, including diabetes, systemic lupus erythematosus, inflammatory bowel disease, asthma/atopy, multiple sclerosis, and RA. The rat models appear to provide a powerful complementary approach to identify and characterize candidate genes that may contribute to autoimmune diseases in several species.

Identification of four new quantitative trait loci regulating arthritis severity and one new quantitative trait locus regulating autoantibody production in rats with collagen-induced arthritis.

OBJECTIVE: Collagen-induced arthritis (CIA) is a polygenic model of experimentally induced autoimmunity and chronic joint inflammation. This study maps genetic loci that regulate CIA susceptibility in DA/Bkl (DA) and BN/SsNHsd (BN) rats. METHODS: Genome scans covering chromosomes 1-20 and interval mapping techniques using 159 simple sequence-length polymorphism markers were used to identify quantitative trait loci (QTLs) that regulate CIA in (DA x BN)F2 hybrids. Serum antibody titers to type II collagen were determined by enzyme-linked immunosorbent assay. RESULTS: DA rats were high responders to porcine type II collagen (PII) and developed severe CIA (100%). BN rats were low responders to PII and resistant to CIA (0%). BN genes strongly repressed PII-induced CIA. Only 12% of (DA x BN)F1 rats (7 of 60) and 31% of (DA x BN)F2 rats (307 of 1,004) developed CIA. Three new QTLs (Cia11, Cia12, and Cia13) with significant logarithm of odds (LOD) scores of 5.6, 4.6, and 4.5, respectively, plus a suggestive QTL (Cia14*, LOD 3.0) regulating arthritis severity were identified on chromosomes 3, 12, 4, and 19. A new QTL, Ciaa3, associating with anticollagen antibody titer (antibody to PII LOD 6.5; antibody to rat type II collagen LOD 5.2) mapped to chromosome 9. Of 10 CIA QTLs previously identified in (DA x F344) and (DA x ACI) rats, only Cia1 in the major histocompatibility complex and a region coincident to Cia5 on chromosome 10 (LOD >8.0) influenced CIA severity in (DA x BN)F2 rats. CONCLUSION: Since CIA exhibits many of the pathologic features of rheumatoid arthritis, the data indicate that the variety of genetic elements regulating human autoimmune and rheumatic diseases may be much larger and more varied than originally envisioned.

Identification of a new non-major histocompatibility complex genetic locus on chromosome 2 that controls disease severity in collagen-induced arthritis in rats.

OBJECTIVE: To identify novel non-major histocompatibility complex (non-MHC) genetic loci controlling the severity of homologous rat type II collagen-induced arthritis (CIA). METHODS: We conducted a genome-wide scan to identify CIA regulatory quantitative trait loci (QTL) in an F2 cross between DA (CIA highly susceptible) and ACI (CIA resistant) inbred rats immunized with homologous rat type II collagen (RII). These strains share the MHC/RT1av1 haplotype required for susceptibility to RII-induced CIA. RESULTS: F2 females had higher median arthritis scores than did males. Relative resistance in the males was determined by inheriting either a DA or an ACI Y chromosome and was independent of the source of the X chromosome. In addition, a major QTL was localized on chromosome 2 (Cia7, logarithm of odds score 4.6). Cia7 is in a region that shows linkage conservation with chromosomal regions that regulate autoimmune diabetes and experimental autoimmune encephalomyelitis in mice and multiple sclerosis in humans. CONCLUSION: Sex chromosomes and Cia7 play an important role in regulating CIA in response to RII. This rat model should facilitate positional cloning and functional characterization of regulatory genes that may play a role in several forms of autoimmune disease, including rheumatoid arthritis.