bluuebunny/crossref_metadata_2025 huggingface dataset:
von Willebrand factor‐cleaving protease activity in congenital thrombotic thrombocytopenic purpura
Authors: Allford S. L. , Harrison P. , Lawrie A. S. , Liesner R. , Mackie I. J. , Machin S. J.
Published: July 2010

Thrombotic thrombocytopenic purpura (TTP) is characterized by microangiopathic haemolytic anaemia (MAHA), thrombocytopenia, fluctuating neurological impairment, renal dysfunction and fever. Both acquired and congenital forms are recognized. Recurrent episodes, which may be predictable (occurring every 21–28 d), are seen in congenital disease and may be treated by infusion with fresh‐frozen plasma (FFP). Congenital TTP has recently been associated with deficiency of a novel von Willebrand factor (VWF)‐cleaving protease. To investigate whether residual protease activity dictates clinical manifestations, we determined protease activity in three patients with congenital TTP of varying severity. Intrinsic VWF‐cleaving protease activity of a range of plasma‐derived products was also assessed as one patient had been successfully maintained for many years, initially using an intermediate‐purity factor VIII concentrate (Kryobulin) and then cryoprecipitate. All three patients had a severe absolute deficiency of VWF‐cleaving protease activity (< 3%) up to 5 months after clinical symptoms. Three relatives were also found to have a mild reduction in protease activity (25–50%). Nevertheless, the intrinsic VWF‐cleaving protease activity of plasma‐derived products correlated with their clinical efficacy: significant (100%) protease activity was found in FFP, cryosupernatant, solvent–detergent‐treated plasma, cryoprecipitate and Kryobulin. Two clinically ineffective factor VIII products (Fahndi and Haemate P) possessed only low protease activity (6·25% and 12·5% respectively). Although this suggests that VWF‐cleaving protease activity is central to the pathogenesis of congenital TTP, either small differences in protease activity below 3% or hitherto unknown factors have a profound influence on clinical phenotype. The possible use of factor VIII concentrates in the treatment of this condition also warrants further investigation.
Ribosomal dysfunction and inherited marrow failure
Authors: Ganapathi Karthik A. , Shimamura Akiko
Published: July 2010

Impairment of ribosome biogenesis or function characterizes several of the inherited bone marrow failure syndromes: Diamond‐Blackfan anaemia, dyskeratosis congenita (DC), Shwachman‐Diamond syndrome and cartilage‐hair hypoplasia. These syndromes exhibit overlapping but distinct clinical phenotypes and each disorder involves different aspects of ribosomal biogenesis. The clinical characteristics of each syndrome are briefly reviewed. Molecular studies of ribosome biogenesis and function in each of these syndromes are discussed. Models of how impairment of ribosomal pathways might affect haematopoiesis and tumorigenesis are explored.
The role of macrophage activation and ofBcg-encoded macrophage function(s) in the control ofMycobacterium aviuminfection in mice
Authors: APPELBERG R , SARMENTO A M
Published: July 2010

Following the intraperitoneal inoculation of 2.5 × 108 colony-forming units of Mycobacterium avium strain ATCC 25291, there was bacillary growth in the liver, spleen and peritoneal cavity of C57BL/6, C57BL/10, DBA/1 and BALB/c mice whereas DBA/2, C3H/He, CBA/Ca and CD-1 mice controlled the infection showing constant or slightly decreasing numbers of viable bacteria in the liver and spleen and effective clearance of the bacilli from the peritoneal cavities. The acquisition of non-specific resistance (NSR) to Listeria monocytogenes during the infection by M. avium was high in C57BL/6, BALB/c and C3H/He mice and negligible in DBA/2 and CD-1 mice. The magnitude of the acquisition of NSR was reduced in T cell-deficient mice and was directly proportional to the dose of the inoculum of M. avium. The production of hydrogen peroxide by phorbol myristate acetate-stimulated peritoneal macrophages of M. avium-infected mice was higher in C57BL/6 and BALB/c mice than in CD-1, DBA/2 and C3H/He animals. BALB/c. Begr (C.D2) mice, unlike their congenic strain BALB/c, restricted bacterial growth following the intravenous inoculation of 2.5 × 108 CFU of M. avium as efficiently as DBA/2 mice. C.D2 and BALB/c peritoneal macrophages from infected mice produced similar amounts of H2O2 but BALB/c mice developed higher levels of NSR to listeria than C.D2 mice. The production of nitrite by peritoneal macrophages from infected mice was found to be enhanced in DBA/2 and C3H/He but not in BALB/c, C57BL/6, CD-1 and C.D2 mice. Resident peritoneal macrophages from C.D2 mice were more bacteriostatic in vitro for M. avium than macrophages from BALB/c mice. The same relative differences between the two macrophage populations were observed when the cells were activated with lymphokines. The results show that the resistance to M. avium infection in mice is under the control of the Bcg gene and that susceptibility may be due to some defect in macrophage antibacterial function not completely overcome by the activation of this phagocyte in the susceptible strains of mice.
Human IgG anti-F(ab′)2 antibodies possess rheumatoid factor activity
Authors: GERARDO S HUNT , PERSSELIN J E , STEVENS R H
Published: July 2010

Individual preparations of affinity purified anti-F(ab′)2 antibodies and anti-Fc antibodies isolated from the sera of patients with rheumatoid arthritis (RA), were examined for reactivity with the Fab and Fc fragments of human IgG. Western blot assays demonstrated specific interaction of affinitypurified anti-Fab antibodies with both Fab and Fc molecules. Approximately one-half of the anti-Fab antibody preparations studied contained IgG antibodies reactive with Fab and Fc fragments in ELISA, suggesting the existence of naturally occurring epibody-like autoantibodies in these patients. Thirteen of 14 affinity-purified anti-Fc antibody preparations contained IgG cross-reactive with Fab molecules in ELISA. Double-adsorption assays on affinity columns demonstrated that a minimum of 14%, and possibly as much as 50%, of the IgG anti-Fab antibodies reacted with the Fc of IgG. Conversely, a minimum of 12%, and possibly as much as 70%, of the IgG anti-Fc antibodies reacted with IgG Fab molecules. Anti-Fab antibodies isolated from non-RA individuals also exhibited anti-Fc reactivity in ELISA. demonstrating the presence of these dual-reactive antibodies in other autoimmune and normal individuals. These studies establish the presence of naturally occurring IgG autoantibodies reactive with both the Fab and Fc fragments of human IgG. Their existence emphasizes the potential of anti-immunoglobulin antibodies to recognize a multiplicity of antigens, possibly including other members of the immunoglobulin supergene family.
Immunosuppressive activity of FK-506 in rats: flow cytometric analysis of lymphocyte populations in blood, spleen and thymus during treatment and following drug withdrawal
Authors: WOO J , ROSS C S K , MILTON J I , THOMSON A W
Published: July 2010

Rats were immunized systemically with sheep red blood cells (SRBC) and given either FK-506 (I mg/ kg) or drug vehicle by i.m. injection for 7 days. In animals receiving FK-506, there was suppression (87%) of the splenic plaque-forming cell response on day 4 and marked reductions in the serum antibody litre throughout the 3-week period following immunization. Sequential flow cytometric analyses of blood lymphocytes revealed statistically significant attenuation, by FK-506. of the increase in relative numbers of OX-12+ (B) cells between days 4 and 7. Following drug withdrawal, OX-12 values remained elevated, whereas in control animals a decline was observed. These changes were reflected in concomitant increases in the relative numbers of OX-19+ (CD3+), W3/25+ (CD4+) and OX-8+ (CD8+) T cells; however, due to an overall reduction in lymphocytes by day 7, absolute values were not significantly affected compared with controls. The pattern of changes in OX-6+ (MHC class II+) cells in blood was similar to that observed for B cells. FK-506 also suppressed increases in the small proportion of blood-borne OX-40+ (activated CD4+) cells and OX-39+ (interleukin-2 receptor+) cells in the 7 day period following immunization; thereafter values for activation marker expression between treatment and control groups were similar. In the spleen, there were fewer significant differences between FK-506 and control groups in the incidences of cells expressing the above markers. OX-8+ cells, however, were significantly higher in drug-treated animals on day 7. and there were also reductions in the small proportions of OX-39+ and OX-40+ cells when compared with controls. In the thymus, reversible medullary atrophy induced by FK-506 was accompanied on day 7 by increases in the incidence of CD4+ and CD8+ cells and by a concomitant reduction in OX-44+ mature, medullary thymocytes. Two weeks after drug withdrawal, the phenotypic marker expression profile had been restored to normal in blood, spleen and thymus. These data provide new information on the apparent capacity of FK-506 to interfere with T cell maturation and its influence on lymphocyte activation in vivo.
Autoimmune syndrome after induction of neonatal tolerance to alloantigens: analysis of the role of donor T cells in the induction of autoimmunity
Authors: MERINO J , SCHURMANS S , WEN L , BRIGHOUSE G , LUZUY S , LAMBERT P-H
Published: July 2010

The injection of (C57BL/6 × BALB/c) F1 spleen cells into BALB/c newborn mice leads to activation of persisting F1 donor B cells and development of a lupus-like syndrome in tolerized BALB/c mice. This syndrome is characterized by hypergammaglobulinaemia, high levels of anti-DNA and anti-Sm antibodies, circulating immune complexes and deposits of immunoglobulin in renal glomeruli. The role of donor T cells in this model was investigated by injecting the newborn mice with F1 cells depleted in different T cell subsets by using specific monoclonal antibodies (MoAbs). Tolerance, as shown by an absence of H-2b-specific CTL alloreactivity and persistence of immunoglobulin bearing the donor allotype were observed in mice injected with F1 cells previously depleted in the CD4+ and/ or CD8+ T cell subsets as well as in those which received Thy-1+-depleted F1 spleen cells. In these mice, a typical autoimmune syndrome was found, including splenomegaly and lymphadenopathy, anti-ssDNA and anti-aortic myosin IgG antibodies and renal deposition of immunoglobulin. However, some quantitative changes were seen: the levels of anti-aortic myosin antibodies were lower in mice tolerized with CD4+-depleted F1 cells than in those receiving untreated F1 cells. Conversely, higher levels of these autoantibodies were observed in mice tolerized with CD8+-depleted F1 cells. These results suggest that mature donor T cells are not necessary neither for the establishment of neonatal tolerance to alloantigens nor for the activation of F1 donor B cells in the production of the autoimmune syndrome in tolerant mice, but they may contribute in the regulation of the expression of autoreactive B cell clones.
Increased production of the third component of complement (C3) by monocytes from patients with systemic lupus erythematosus
Authors: TSUKAMOTO H , UEDA A , NAGASAWA K , TADA Y , NIHO Y
Published: July 2010

We measured in vitro C3 production by peripheral blood monocytes from patients with systemic lupus erythematosus (SLE), and found it to be significantly greater than that from normal controls. We also found that monocytes from SLE patients with active disease produced a markedly larger amount of C3 than those from SLE patients with inactive disease. Production of C3 by monocytes correlated with serum levels of anti-dsDNA antibodies and inversely correlated with serum C3 levels in SLE patients. Serial measurement of C3 in the culture supernatant from each SLE patient showed that C3 production by monocytes fell in parallel with a decrease of disease activity. The effect of corticosteroids was ruled out as there was no relation between the level of C3 production by monocytes and the dose of prednisolone. This seems to be the first study in which the C3 production was assayed at a cellular level in SLE patients, and this study suggests that the local C3 production is increased in SLE patients.
A human monoclonal IgM with autoantibody activities against heparan sulphate and the mitotic spindle
Authors: ROUSSEL B , ARVIEUX J , JACOB M C , LORIMIER P , CAVIGIOLI E , MICOUIN C
Published: July 2010

A monoclonal IgM κ from a patient with Waldenström's macroglobulinaemia (IgM-Rod) was found to react at temperatures below 28°C with all tissue basement membranes and the cell coat of non-haematopoietic cells. IgM-Rod antibody was directed against heparan sulphate side chains of heparan sulphate proteoglycans as shown by binding in a solid-phase ELISA to heparan sulphate glycosaminoglycans but not to other purified subcomponents of the extracellular matrix; and by specific inhibition of the observed reactivity by heparitinase treatment. IgM-Rod showed crossreactivity by indirect immunofluorescencc with an as yet unidentified structure expressed in the nucleus during cell division and becoming associated with the mitotic spindle apparatus. The coexistence of both binding activities for heparan sulphate and nuclei determinants in the same IgM molecule was deduced from adsorption-elution experiments and from the inhibitory effect of a mouse monoclonal anti-idiotypic antibody directed against the paratope of IgM-Rod.
IgG isotype and isotype specificity of murine monoclonal IgG rheumatoid factors
Authors: TAGUCHI H , KANOH M , TAKUBO N , KADOTA S , KANAZAWA K , HITSUMOTO Y , SHIBATA T , UTSUMI S
Published: July 2010

Immune complexes of lipopoly saccharide (LPS) with homologous IgG antibody induces rheumatoid factor (RF) predominantly of the IgG class in normal mice, while LPS alone induces mostly IgM RF directed to homologous IgG1. In this study, IgG monoclonal RFs (mRF) were prepared from hybridomas derived from spleen cells of BALB/c mice which were immunized with complexes of TNP-LPS with anti-TNP mouse IgG and their specificity to mouse IgG subclasses was assessed by analysing dissociation kinetics of the ligands due to RF-specific and non-specific interactions. Of the 19 IgG mRFs (11 IgG1, five IgG2a, one IgG2b and two IgG3 types) tested, 14 were directed to either IgG3 or IgG2b or both, while only one exhibited a significant binding capacity to IgG1. Other mRFs, although reactive to rabbit IgG, exhibited little homophilic activity. None of these mRFs reacted strongly with their own isotypes. The results suggest that the IgG RF producing cells are not direct progenies of the IgG1-directed IgM RF-producing cells but may have developed via a rigorous selection process to eliminate clones that produce self-reactive RF.
Functional and phenotypic analysis of T lymphocytes cloned from the skin of patients with systemic sclerosis
Authors: FERRARINI M , STEENE V , MEDSGER T A , WHITESIDE T L
Published: July 2010

Activated T lymphocytes often accumulate in the‘ower dermis of patients with systemic selerosis (seleroderma) any may play a role in the development of dermal libresis. We propagated and cloned these cells directly from skin biopsies in four of eight cases of early, antreated systemic selerosis with diffuse seleroderma. The cloning frequency estimates were f – 0.20 and f – 0.48 for T cells derived from the skin of two patients versus f - 0.68 and f - 0.96 for autologous blood T lymphocytes, All but one of 24 skin-derived selerederma clones were CD4+. Clonal analyses performed with CD4+ clones from patients and normal controls showed that all but one skin-derived clones synthesized either laterferon-gamma (60%), glycosantinolgycan-stimulatory factor (26%) or both (9%) when induced in vitro by a nitrogen, concanavalin A, but not by antologous dermal fibroblasts. In contrast, blood-derived clones had a different functional phenotype. All skin-derived clones produced tumour accrosis factor-alpha. Our results demonstrate that T lymphecytes obtained from the skin of patients with systemic selerois synthesized cytokoines which could modulale functions of human dermal fibroblasts.
Confirmation of a false-positive result associated with a competition inhibition assay used for detecting antibodies to a protein epitope ofMycobacterium leprae
Authors: VADIEE A R , GILLIS T P , SHANNON E J
Published: July 2010

A competitive antibody-binding assay (CABA) was developed to detect antibodies in infected armadillos and leprosy patients which compete with an M. leprae-specific125I monoclonal antibody IIIE9 for the species-specific M. leprae-IIIE9 epitope on the 65-kD protein. The results suggest armadillos and leprosy patients produce antibodies thai inhibit the binding of I2SI-IIIE9 monoclonal antibody to the IIIE9 epitope on crude, native 65-kD protein preparations. When purified, recombinant 65-kD protein was substituted for crude antigen, there was no evidence in the CABA of antibody to the IIIE9 epitope. False-positive results, possibly induced by steric hindrance, are likely to be associated with CABA which incorporate crude cell wall extracts as solid-phase antigen.
Natural killer cell-mediated lysis of T cell lines chronically infected with HIV-1
Authors: BANDYOPADHYAY S , ZIEGNER U , CAMPBELL D E , MILLER D S , HOXIE J A , STARR S E
Published: July 2010

The susceptibility of HIV-1-infected CD4+ T cell lines to natural killer(NK) cell-mediated lysis was examined. Non-adherent peripheral blood mononuclear cells (PBMC) of healthy adults lysed HUT cells chronically infected with the HJB or WMJI strains of HIV-1 to a significantly grater extent than uningected HUT cells. In contrast, Sup-T1 cells chronically infected with these two strains of HIV-1 were not lysed to a greater extent than uninfected Sup-T1 cells. Clone AI. 25-infected Sup. T1 (A1.25/Sup. T1), derived from HIB-infected Sup. T1 cells (HIB/Sup-T1), were susceptible to non-adherent PBMC-mediated lysis as were A1.25-infected HUT cells (A1.25/HUT). When non-adherent PBMC were depleted of CD16 (Leu-Hb) NK cells by treatment with and-Leu-Hb plus C lysis of HIV-1-infected HUT or Sup-T1 cells was reduced to low levels, indicating that the lysis was mediated by NK cells. Expression of HIV antigens on these target cells did not correlate with their susceptibility to NK cell-mediated lysis. Depletion of interferon-alpha (IFN-α) producing HLA-DR1 cells from non-adherent PBMC had no effect on the magnitude of NK cell-mediated lysis of HIB or WMJI-infected HUT cells. In contrast, lysis of A1.25/Sup-T1 or A1.25/HUT cells required the presence of HLA-DR1 cells. IFN-α production appeared to be required for NK cell-mediated lysis of A1.25/Sup-T1 or A1.25/HUT cells, while lysis of Hut cells infected with the WMJI ro HUB strains of HIV-1 was IFN-α independent. These results indicate considerable variability in the susceptibility of different HIV-1 infected T cell lines to NK cell-mediated lysis and suggest the existence of alternative mechanisms of activation of NK cells for lysis of HIV-1-infected T cell lines.
Contact sensitivity in the murine oral mucosa. I. An experimental model of delayed-type hypersensitivity reactions at mucosal surfaces
Authors: AHLFORS E , CZERKINSKY C
Published: July 2010

We have examined in a murine model, the potential of the oral mucosa (OM) to serve as inductive and/or expression site(s) of delayed-type hypersensitivity (DTH) reactions. The expression of DTH reactions in the murine buccal mucosa was studied after topical application of oxazolone or picryl chloride onto the OM of animals previously sensitized with either hapten. Irrespective of the site of priming (skin or buccal mucosa), inflammatory cells appeared in the OM following buccal elicitation with the pertinent hapten. The density of infiltrating cells peaked at 24 h after hapten elicitation. Such inflammatory reactions, which comprised mainly mononuclear cells at 24 h, were preceded by an early inflammatory reaction that developed only in animals previously sensitized at skin sites, This early reaction, comprising mainly PMN neutrophils, peaked at 6–8 h, declined by 8–16 h, and was not observed in mice previously sensitized in the buccal mucosa. The 24 h reactions failed to develop in nude mice similarly treated, in intact unsensitized mice, as well as in animals sensitized with an irrelevant hapten. These reactions could be adoptively transferred to naive animals by LN cells but not by serum from sensitized syngeneic donors. Furthermore, LN cell suspensions depleted of T cells failed to transfer sensitization for subsequent OM DTH. Topical application of contact sensitizing haptens onto OM induced priming for subsequent DTH reactions elicited with recall antigen applied at a distant skin site or at a local buccal site. These results demonstrate that the OM has the capacity to serve both as an inductive and as an expression site for T cell-mediated inflammatory reactions, be these expressed or induced at local mucosal sites or at remote systemic (skin) sites. This animal model should be valuable for studying the regulation of T cell-mediated inflammatory responses at mucosal surfaces.
Restricted specificity of the autoantibody response in Goodpasture's syndrome demonstrated by two-dimensional Western blotting
Authors: DERRY C J , DUNN M J , REES A J , PUSEY C D
Published: July 2010

The autoantigen in Goodpasture's syndrome is known to be contained within the non-collagenous (NC1) domain of type IV collagen. We have examined the specificity of autoantibodies to glomerular basement membrane (GBM) using the technique of 2-D electrophoresis followed by Western blotting. Protein stains of 2-D gels of collagenase-digested human GBM revealed extensive charge and size heterogeneity. Major components were of mol. wt 24–30 kD and 43–56 kD, corresponding to monomeric and dimeric subunits of NC1. Western blotting of 2-D gels with IgG from patients with anti-GBM disease demonstrated that the most antigenic components migrated as cationic 28-kD monomers (pI 10) and similarly charged dimers, although other components were recognized less strongly. The mobility of the strongly antigenic polypeptides was different to that of the known α l and α2 chains of type IV collagen. Autoantibodies from all 20 patients studied showed the same pattern of reactivity, regardless of their clinical features (in particular, the presence or absence of pulmonary haemorrhage) or HLA type. A monoclonal antibody (P1) to human GBM bound in a similar pattern, particularly recognizing the cationic components. 2-D gels of affinity-purified GBM from a P1 column showed enrichment of the 28-kD monomers, which were recognized by human autoantibodies on Western blotting. These results demonstrate that the autoimmune response in Goodpasture's syndrome is of restricted specificity, and support the suggestion that the major autoantigenic determinant is present on the novel α3 chain of type IV collagen.
Imbalance of CD4 + CD45R+ and CD4+ CD29+ T helper cell subsets in patients with atopic diseases
Authors: SCHAUER U , JUNG T , HEYMANNS J , RIEGER C H L
Published: July 2010

To evaluate the proportion of helper cell subsets we studied 18 children with atopic dermatitis, 30 patients with asthma. 27 healthy age-matched controls aged 1 to 17 years and 11 atopic controls without symptoms related to atopy, aged 9–22 years. Lymphocytes were isolated from heparinized peripheral blood and the proportion of CD4+CD29+ and CD4+CD45R+ cells was determined by double-labelling immunofluorescence. Children with atopic dermatitis yielded a significantly (P<0.0l) higher proportion of CD4+CD45R+ (median 75%) cells compared with normal controls (median 66.6%). whereas the proportion of CD4+CD29+ cells was significantly (P<0.0l) lower in patients with atopic dermatitis (median 204 versus 29.6%). Interestingly, the percentage of CD4+CD45R+ cells shows an age-dependent decline (r= -0.67, P<0.0l) in the control group, which is not found in the patient group.
Recombinant interleukin-1α inhibits the growth of rat mesangial cells in culture
Authors: IKEDA M , IKEDA U , OOHARA T , TAKEDA K , KANO S
Published: July 2010

We have investigated the effect of interleukin-1 (IL-I) on the growth of mesangial cells isolated from rat kidney. Recombinant IL-1α inhibited 3H-thymidine uptake by mesangial cells in a dose-dependent manner in the presence of either 0.5% or 5% fetal bovine serum (FBS). In the presence of high concentration of FBS(10%), the effect of IL-1 was not prominent. The inhibitory effect of IL-1 on the growth of mesangial cells was also confirmed by a change in cell numbers and measurements of protein synthesis with 3H-leucine. IL-1-induced inhibition of mesangial cell growth was not affected by indomethacin. IL-1 showed no effects on intracellular Ca2+ levels in mesangial cells. These observations indicate that IL-1 inhibits the growth of mesangial cells, and thus may play a protective role for mesangial cells from abnormal proliferation in some pathophysiological states.
A subset of γδ lymphocytes is increased during HIV-1 infection
Authors: DE PAOLI P , GENNARI D , MARTELLI P , BASAGLIA G , CROVATTO M , BATTISTIN S , SANTINI C
Published: July 2010

The γδ T cell receptor (TcR) lymphocytes constitute 3–10% of human peripheral blood lymphocytes. Only a very small fraction of these cells is recognized by the δTCS1 monoclonal antibody, directed against the Vγδ1 chain of the receptor. We describe the immunological, virological and clinical data of a small group of seropositive subjects having high levels of γδ TcR T cells in the peripheral blood. Our flow cytometric studies show that most of these cells belong to the δTCS1+ (Vδ1+), CD8± (dim staining) subset. Patients with high γδ TcR T cell numbers were not characterized by the presence of an acute (IgM positive) or reactivated (as defined by high IgG litres against early antigen or IgA titres against viral capsidic antigen) Epstein-Barr virus infection. Cytomegalovirus infection was excluded by serological assays, and other herpesviral infections were not found after clinical examination. HIV p24 antigenaemia was present in two out of 11 subjects. AIDS patients had very high percentages of γδ TcR T cells. Altogether these data show that the selective expansion of δTCS1+ cells in HIV1 seropositive subjects is not related to some exogenous antigen stimulation, but may be related to peculiar pathologic processes involving the immune system.
Immunosuppressive effects of 2-acetyl-4-tetrahydroxybutyl imidazole (THI) in the rat
Authors: GOBIN S J P , PHILLIPS J A
Published: July 2010

THI is a component of ammonia caramel, a widely used food colouring. The effect of THI on the immune system has been determined in the male F344 rat. THI was given in the drinking water at doses of 1, 10 and 50 mg// (equivalent to 01, 1 and 5 mg/kg per day) to animals on a vitamin B6-deficient diet. After 1 week, the immune competence of the animals was assessed under continued THI treatment. No marked changes in thymus or spleen weight were observed after THI treatment, although there was an increased number of pyknotic cells in the thymic cortex, mainly engulfed by macrophages and there appeared to be a slight thinning of the cortex area. THI produced a significant loss in T and B lymphocytes in peripheral blood but not in the spleen. No change in natural killer <NK) cell activity against YAC-1 target cells was observed in the spleen. The observed increase in NK cell activity in peripheral blood was due to an increase in circulating large granular lymphocytes (LGL). Although the serum antibody litre against keyhole limpet haemocyanin (KLH) was not affected by THI treatment, B cells showed less proliferation when cultured with lipopolysaccharide. T cell function was impeded as measured in mitogen-induced proliferation assay, delayed-type hypersensitivity assay and host versus graft (popliteal lymph node) assay. The results indicate that THI is an immunosuppressor in the rat, in whom it can produce profound lymphopenia and suppression of cell-mediated immunity.
Serial study of CD5+ and CD5- B cell subpopulations in 335 HIV seropositive patients
Authors: VUILLIER F , SCOTT-ALGARA D , TORTEVOYE P , PIALOUX G , DIGHIERO G
Published: July 2010

B cell subpopulations, as defined by double-labelling techniques with CD5 and CD19 monoclonal antibodies (MoAbs), were serially studied in 335 HIV-1 seropositive patients. At the time of the first consultation, no important modifications in either CD5+ or CD5- subpopulations were observed, whatever the stage of the disease. However, in 18 out of the 335 patients (5.37%), a sharp increase in 8 cells exceeding 20% and 300/mm3 was observed. This increase in B cells was mainly accounted for CD5-CD19+ B cell subpopulations and was associated with: (i) evolution of the disease, since only four patients presented it at their first consultation (one lymphadenopathy-associated syndrome (LAS) and three AIDS); (ii) advanced stages of disease since, at the time of B cell augmentation, two patients were staged as LAS, four as ARC and 12 as AIDS; (iii) a high incidence of non-Hodgkin’s lymphomas(NHL) since three out of the 18 patients presented a histologically confirmed NHL and three others a clinical pattern compatible with this diagnosis. However, in three patients with B hyperlymphocytosis, polymerase chain reaction (PCR) studies of immunoglobulin gene rearrangement revealed the existence of a polyclonal expansion of B cells. These results justify inclusion of a pan-B cell marker in routine phenotypic studies of HIV-infected individuals, as well as the search for NHL among patients presenting this abnormality.
Dichotomy of two CD8+ lymphocyte subsets in HIV infection. Depletion of CD8+ CD3- and expansion of CD8+ CD3+ subsets: consequence on the CD4/CD8 ratio
Authors: MANSOUR I , DOINEL C , ROUGER P
Published: July 2010

In order to highlight the underlying mechanism(s) of the CD8 lymphocyte expansion in the HIV infection, two distinct CD8 subsets were analysed: T CD8bright+ CD3+ with MHC-restricted activity, and non-T CD8dim+ CD3-, which performs natural killer (NK) activity. It consists of a cross-sectional study including 168 HIV-infected patients (74 CDC stage II, 48 CDC stage III and 46 CDC stage IV) compared among them and to 60 healthy individuals. We observed an expansion of CD8+CD3+ cells which masks a depletion of CD8+CD3-. The comparative study showed that the expansion of the CD8+CD3+ is relatively higher than that of total CD8+ lymphocytes and that the depletion of the CD8+ CD3- subset is severe, begins early and remains constant through the HIV progression. The comparison of CD4/CD8 and CD4/CD8+ CD3+ ratios showed that the latter could possibly be a better indicator in the HIV infection. The mechanism of inverted CD4/CD8 ratio in healthy individuals was also clarified. The CD8+CD3+, CD8+CD3- and CD4/CD8+CD3+ parameters would be more specific markers than total CD8 and CD4/CD8 ratio especially in therapy trials.
Autoantibody stimulation of the human thyrotropin receptor: regulation of adenylate cyclase activity, thyroglobulin and thyroid peroxidase mRNA levels in primary cultures of Graves’ thyroid tissue
Authors: COLLISON K S , BANGA J P , BARNETT P S , HUANG G C , MCGREGOR A M
Published: July 2010

The effects of immunoglobulin preparations from hyperthyroid Graves’ disease patients on primary cultures of thyroid cells have been studied at the mRNA level. Autoantibodies to the thyrotropin (TSH) receptor from these patients, which had been initially characterized by their ability to stimulate adenylale cyclase and inhibit the binding of radiolabelled TSH to thyroid membrane preparations, were studied for their effects on thyroglobulin and thyroid peroxidase mRNA levels. Incubation of thyroid cells with TSH receptor autoantibodies from different Graves'disease patients for 48 h led to time- and dose-dependent increases in the levels of thyroid peroxidase and thyroglobulin mRNA in primary cultures of thyrocytes. The incomplete correlation between G protein-linked adenylate cyclase activation and thyroid mRNA elevation indicates the possibility of the involvement of alternative second messenger pathways in the regulation of thyroid cell function and differentiation.
Reduction in Tγδcell numbers and alteration in subset distribution in systemic lupus erythematosus
Authors: LUNARDI C , MARGUERIE C , BOWNESS P , WALPORT M J , SO A K
Published: July 2010

We have studied the distribution of Tγδ cells in the peripheral blood of 35 patients with systemic lupus erythematosus (SLE) and 36 age-matched controls. The monoclonal antibodies A13, BB3 and TiγA, which are specific for the Vδ1, Vδ2 and Vδ9 gene products respectively, were used to define Tγδ cell subsets. A significantly lower frequency of Tγδ cells was found in peripheral blood lymphocytes of SLE patients compared with normal subjects (3.2%versus 5.9%). There was a marked reduction in the Vδ2+ subset of Tγδ cells, which resulted in a reversal of the ratio of Vδ2+/Vδ1+ cells from 4.34 to 0.56. No correlation was found with either clinical or laboratory measures of disease activity. These results suggest that the observed changed in Tγδ subset distribution are related to the SLE itself, and not secondary to changes in disease activity.
REACTION OF COMPLEMENT WITH ENDOTHEUAL CELLS IN A MODEL OF XEN0TRANSPLANTATION
Authors: Dalmasso A P , PIatt J L , Bach F H
Published: July 2010

We review our studies on the role of complement (C) as mediator of xenograft hyperacute rejection using an in vitro model consisting of porcine endothelial cells as target and human serum as source of natural antibodies and C. Cytotoxicity of endothelial cells required IgM antibodies to porcine endothelial cells, and the classical pathway and membrane attack complex of C. These findings correlated with in vivo results of porcine organs transplanted into rhesus monkeys, which showed a) co-deposition of IgM, C3, C4 and C9, along blood vessels of rejecting organs, with trace deposits of factors B or P, and b) minimal deposition of IgM and C components in transplants with prolonged survival that were performed in rtiesus monkeys depleted of natural antibodies but with normal C levels. Human serum causes activation of porcine endothelial cells manifested by release of heparan sulfate proteogiycan. Heparan sulfate release was induced by C5a alone. A new approach to avert xenograft hyperacute rejection was tested. To inhibit cytotoxicity of porcine endothelial cells by human C, the membrane-associated C inhibitor decay-accelerating factor (DAF) of human origin was incorporated into endothelial cells. Human DAF was able to efficiently inhibit C-mediated killing of porcine endothelial cells, suggesting that the use of DAF and other C inhibitors could be used to interfere with C-mediated xenograft hyperacute rejection.
Effects ofin vivohyperthermia on natural killer cell activity,in vitroproliferative responses and blood mononuclear cell subpopulations
Authors: KAPPEL M , STADEAGER C , TVEDE N , GALBO H , PEDERSEN B KLARLUND
Published: July 2010

This work was designed to test the hypothesis that elevations in body temperature of humans induce immunostimulalion. Eight healthy volunteers were immersed in a water bath (water temperature 39.5°C) for 2 h. during which their rectal temperature rose to 39.5°C. On a later day they served as their own controls, being immersed into thermoneutral water (34.5°C) for 2 h. Blood samples were collected before immersion, at body temperatures of 38°C, 39°C and 39.5° C, and 2 h after water immersion. The interleukin-2 (IL-2) enhanced natural killer (NK) cell activity (lysis per fixed number of mononuclear cells), as well as the proportion and total number of NK cells (CDI6+ cells), increased significantly during hyperthermia compared with control values. The lymphocyte proliferative responses did not differ significantly between hyperthermia and thermoneutral conditions. The proportion of pan-T (CD3+) cells was maximally depressed 2 h after water immersion. The decreased proportion of CD3+ cells was mainly due to a decreased percentage of CD4+ cells (not significant). The proportion of B cells (CD19+ cells) did not fluctuate significantly, while a marked and significant increase in monocyte proportion (CD14+ cells) was found 2 h after hyperthermia. Two hours after hot water immersion the lymphocyte concentration declined while the neutrophil and monocyte concentrations were augmented. Induced hyperthermia causes signifi cantly increased serum cortisol. plasma norepinephrine and plasma epinephrine concentrations compared to controls. It is possible that the altered immune functions induced by elevated body temperature can be ascribed to altered composition and function of blood mononuclear cells induced by elevated levels of stress hormones.
Human immunoglobulin production in immunodeficient mice: enhancement by immunosuppression of host andin vitroactivation of human mononuclear cells
Authors: CAVACINI L A , KENNEL M , LALLY E V , POSNER M R , QUINN A
Published: July 2010

The affect of host and donor related factors on successful cngraftmenl of human cells into mice was examined to minimize the variability lhal has been observed in successful development of human mouse chimera for the study of human disease and immune physiology and regulation. Human immunoglobulin production in severe combined immunodeficiency (SCID) mice engrafted with human peripheral blood mononuclear cells (PBMC) was augmented by immunosupprcssing recipient mice and activating donor PBMC. Immunosuppression of recipient mice with 3 Gy of γ- irradiation induced a 10-fold increase in human igG in the sera of engrafted SCID mice. Variation in production of human IgG in recipient mice correlated with preinjection phenotype and activation status of injected PBMC. Mice injected with PBMC with a low CD4/CD8 ratio (less than 0·5) produced no delectable circulating human immunoglobulin. When the CD4./CD8 ratio was greater than 1·5. human IgG was detected in sera of PBMC-recipient SCID mice. Serum IgG increased 10-fold following in vitro activation of donor PBMC with anti-CD3. IL-2 and Slaphylococcus aureus. Successful engraflment and serum IgG production was evidenced by an increase in the recovery of activated human IgG cells in the spleens of mice with maximal IgG production. Optimization of functional engraftment required modification of both the host (SCID mice) and the donor cells.
Definition of an immunodominant T cell epitope contained in the envelope gp41 sequence of HIV-1
Authors: BELL S J D , COOPER D A , KEMP B E , DOHERTY R R , PENNY R
Published: July 2010

The majority of the immunodominant amino acid sequences of HIV-I that have been characterized to date are coded for by hypervariable gene sequences. These variable sequences are however interspersed with sequences that are highly conserved between HIV strains. Immunogenic viral products with amino acid sequences that vary minimally between strains, and that consistently elicit both humoral and cellular immune responses, may be ideal for inclusion in a subunit vaccine. We studied HIV-seronegative and HIV-infected persons, classified as asymptomatic (AS), ARC or AIDS, initially, we assessed the cellular immune status of each subject from results of T cell phenotype analyses, assays for serum levels of surrogate markers of disease progression, and responses to mitogens and recall antigen. In addition, we tested whether three short synthetic peptides derived from the conserved sequences of the envelope gp 120 (aa 262–284) and gp41 (aa 579–601), and core p 17 (aa 106–125) regions of the HTLV-I MB isolate, could elicit B cell as well as T cell responses in HIV-infected subjects. Only the gp41-derived sequence was immunogenic at both B and T cell levels. To further characterize the gp41 epitope. we used a series of overlapping synthetic peptides derived from aeonserved region of the envelope gp41 (aa 572–613). We thus identified an immunodominant 12-mer peptide sequence. gp41 (8K) (aa 593–604), which consistently elicited both T cell blastogenic and B cell (antibody) responses in AS HIV-seropositive individuals but not in ARC and AIDS patients. Linear regression analysis showed that in AS persons there was a strong positive correlation (P<0·0005) between the absolute CD8* T cell numbers and the magnitude of blastogenic responses to the gp41(8)(aa 593–604). Furthermore, those AS subjects with T cells that proliferated in response to this gp41 analogue also had significantly greater serum levels of antibody to the same short peptide sequence than symptomatic ARC and AIDS patients. These results suggest that cellular responses to the immunodominant and highly conserved envelope sequences of HIV-1, associated with increased CDS+ T cells, may be important in the pathogenesis of HIV disease.
Adenosine-deaminase-associated immunodeficiency. I. Differential sensitivities of lymphocyte subpopulations exposed to 2-deoxycoformycinin vivo
Authors: BAGASRA O , HOWEEDY A , POMERANTZ R J
Published: July 2010

In order to obtain a better understanding of the degree of immune dysfunctions caused by the absence of adenosine deaminase, we gave a single i.p. injection of 2′-deoxycoformycin (2-dcf), a potent inhibitor of the enzyme ADA at various doses into adult Syrian hamsters. These animals were examined for their ability to mount primary in vivo antibody responses to helper T cell dependent (Th-d) and helper T cell independent (Th-ind) antigens. Hamsters treated with 0·5 mg/kg of 2-dcf mounted enhanced splenic plaque-forming cell (PFC) responses to sheep erythrocytes, a Th-d antigen, and to pneumococcal polysaccharide type III (SIII), a Th-ind antigen. Treatment of animals with 1·0 mg/kg of 2-dcf resulted in a significantly depressed (P < 0·001) PFC response to Th-d antigen, but a further enhanced response to Th-ind antigen. One mechanism which may be responsible for such a dichotomous response to these two types of antigens was selective dysfunction of T cell subpopulations. At higher doses (1·5–4·0 mg/kg), PFC responses to both types of antigens were significantly suppressed. Immunoenhancement at low doses of 2-def was attributed to an increased susceptibility of T suppressor cells to 2-dcf. This hypothesis was confirmed by priming the 2-dcf-treated animals with low-dose Th-ind antigens. These animals failed to induce low-dose tolerance by stimulation of antigen-specific suppressor T cell subsets. At low doses, B cells and T helper cell functions were found to be intact, as further confirmed by priming the animals with the carrier keyhole limpet haemocyanin (KLH) and challenging with trinitrophenyl-KLH. This dose-dependent selective susceptibility of various T cell subpopulations and B cells may explain the heterogeneity of clinical, biochemical and immunological parameters observed in children with ADA deficiency severe combined immunodeficiency.
Epitope-specific induction of mesangial lesions with proteinuria by a MoAb against mesangial cell surface antigen
Authors: KAWACHI H , ORIKASA M , MATSUI K , IWANAGA T , TOYABE S , OITE T , SHIMIZU F
Published: July 2010

A MoAb 1–22–3 (igG3) was produced in mice immunized with rat glomeruli. A blotting study indicated the antigen molecule recognized by this MoAb has a molecular weight of about 25 kD, which is the same as that of the Thy 1.1 molecule. This MoAb is capable of inducing the morphological changes similar to those induced by anti-thymocyte serum or the anti-Thy 1.1 MoAb, ER4 and massive proteinuria in rats by a single i.v. injection. Proteinuria started immediately after MoAb 1–22–3 injection and peaked on day 5. Reaction products were detected by immunoelectron microscopy in vitro on the limited mesangiai cell surface facing endothelial cells and in vivo in partially lysed mesangial cells 30 min alter injection. Unlike the proteinuria-inducing MoAb ER4, reactivity of MoAb 1–22–3 was detected neither on endothelial cells, epithelial cells, nor along the glomerular basement membrane in vivo and in vitro. There is a difference in reactivity toward guinea-pig and rabbit materials between MoAb 1–22–3 and the commercial anti-Thy 1.1 MoAb(OX7). The antigenic determinant of MoAb 1–22–3 is concluded to be a new epitope and only the binding of MoAb 1–22–3 to this epitope proved to lead to an abnormal increase of glomerular capillary wall permeability.
Increased frequency of the long (S) allotype of CR1 (the C3b/C4b receptor, CD35) in patients with systemic lupus erythematosus
Authors: CORNILLET P , GREDY P , PENNAFORTE J L , MEYER O , KAZATCHKINE M D , COHEN J H M
Published: July 2010

The allotypic forms of the C3b/C4b receptor (CR1, CD35) differ in length, in the number of expressed C3b binding sites and thus in their ability to mediate the processing of circulating C3- and C4-bearing immune complexes. We have used a combination of three informative restriction fragment length polymorphisms (RFLPs) to assess the frequencies of the F (most frequent allele comprised of four long homologous repeats (LHR)), S (five LHR) and F′ (three LHR) alleles of the C3b/C4b receptor (CR1, CD35) in a French population of patients with systemic lupus erythematosus (SLE) (n= 63) and healthy controls (n= 158). A significantly higher frequency of the S phenotype was observed among patients (51%) as compared with controls (26%). The F′allele was found in 2/61 patients and 1/85 healthy controls, indicating the rare occurrence of the short CR1 allele in SLE. This allele is also extremely rare in the normal population. The overrepresentation of the S long allele among patients is indicative of a genetic linkage between CR1 and susceptibility to SLE.
IgG antibodies from patients with primary Sjögren's syndrome and systemic lupus erythematosus recognize different epitopes in 60-kD SSA/Ro protein
Authors: BARAKAT S , MEYER O , TORTEROTOT F , YOUINOU P , BRIAND J P , KAHN M F , MULLER S
Published: July 2010

Five synthetic peptides corresponding to the N-, the C- and a central domain in 60-kD SSA/Ro protein were prepared and tested with sera from 112 patients with systemic lupus erythematosus (SLE), 55 with primary Sjögren's syndrome (pSS) and 29 with rheumatoid arthritis. Among these five fragments, one representing residues 21-41, was recognized by antibodies in 57% of pSS patients. Interestingly, this peptide was recognized by only a few (≤7%) of SLE sera, while 63% of pSS sera and 46% of SLE sera tested in parallel possessed antibodies reacting in ELISA with purified 60-kD SSA protein. The ELISA results were compared with the pattern of reactivity obtained in immunodiffusion and immunoblotting. The results indicate that the sensitivity of ELISA using peptide 21-41 and pSS sera was in the same range as immunoblotting and higher than immunodiffusion. Thus the peptide 21-41 proved useful for the detection of anti-SSA antibodies in the sera of patients with pSS. Furthermore, a positive ELISA using peptide 21–41 could be of potential use to discriminate pSS with systemic features from SLE. The fact that peptide 21–41 is recognized by antibodies in pSS but only by very few SLE sera implies that different mechanisms are involved in the anti-SSA immune response in these two autoimmune diseases.
ANCA and associated diseases: immunodiagnostic and pathogenetic aspects
Authors: GROSS W L , SCHMITT W H , CSERNOK E
Published: July 2010

The past decade has seen an explosion of data on the new group of autoantibodies known collectively as ANCA (anti-neutrophil cytoplasmic antibodies). ANCA are specific for granule proteins of granulocytes and monocytes and induce distinct fluorescence patterns, e.g. the cytoplasmic (classic) cANCA and the perinuclear pANCA. cANCA is induced by antibodies directed against Proteinase 3 (PR3; PR3-ANCA) in about 90% of all ANCA-positive sera, and pANCA is induced by antibodies against myeloperoxidase (MPO; MPO-ANCA) in about 40%. A further staining pattern, which does not have a clear cut association with a distinct granule protein, is sometimes seen in chronic inflammatory bowel diseases. PR3-ANCA are serological markers for Wegener's granulomatosis (WG) and MPO-ANCA are associated with certain subtypes of primary vasculitides. Evidence exists that both the autoantigen and ANCA participate in the pathogenesis of at least the group of ‘ANCA-associated vasculitides’.