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1.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(2): 200-203, 2021 Feb 09.
Artigo em Chinês | MEDLINE | ID: mdl-33557506

RESUMO

As the national key discipline and the initiator of oral and maxillofacial deformity group, the Department of Oral and Maxillofacial Surgery persisted in teaching, designed a novel teaching form combining theoretical knowledge and online software practice according to the characteristics of our discipline and carried out "cloud training" via the National Oral Telemedicine Education Platform. Ten lecturers, 325 theoretical students and 50 practical students were investigated by questionnaire in the present study with questions focusing on the geographical distribution and composition of personnel, etc. The results showed that the online course covered a wide range of students and achieved high acceptance and satisfaction rate. The first online software operation course was conducted in an orderly manner, with timely interaction between teachers and students. The students were able to master the design process skillfully. This "cloud training" has achieved good results, but there are still a series of problems that have yet to be resolved, such as network stalls and protection of intellectual property rights. Under the new form, the exploration and analysis of the new mode of online telemedicine specialist education will provide some practical reference for the National Clinical Research Center for Oral Diseases to carry out online telemedicine teaching in the future.


Assuntos
COVID-19 , Educação Médica , China , Hospitais , Humanos , Pandemias , SARS-CoV-2
2.
Plant Cell Rep ; 39(1): 19-33, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31485784

RESUMO

KEY MESSAGE: WSL8 encoding a deoxyribonucleoside kinase (dNK) that catalyzes the first step in the salvage pathway of nucleotide synthesis plays an important role in early chloroplast development in rice. The chloroplast is an organelle that converts light energy into chemical energy; therefore, the normal differentiation and development of chloroplast are pivotal for plant survival. Deoxyribonucleoside kinases (dNKs) play an important role in the salvage pathway of nucleotides. However, the relationship between dNKs and chloroplast development remains elusive. Here, we identified a white stripe leaf 8 (wsl8) mutant that exhibited a white stripe leaf phenotype at seedling stage (before the four-leaf stage). The mutant showed a significantly lower chlorophyll content and defective chloroplast morphology, whereas higher reactive oxygen species than the wild type. As the leaf developed, the chlorotic mutant plants gradually turned green, accompanied by the restoration in chlorophyll accumulation and chloroplast ultrastructure. Map-based cloning revealed that WSL8 encodes a dNK on chromosome 5. Compared with the wild type, a C-to-G single base substitution occurred in the wsl8 mutant, which caused a missense mutation (Leu 349 Val) and significantly reduced dNK enzyme activity. A subcellular localization experiment showed the WSL8 protein was targeted in the chloroplast and its transcripts were expressed in various tissues, with more abundance in young leaves and nodes. Ribosome and RNA-sequencing analysis indicated that some components and genes related to ribosome biosynthesis were down-regulated in the mutant. An exogenous feeding experiment suggested that the WSL8 performed the enzymic activity of thymidine kinase, especially functioning in the salvage synthesis of thymidine monophosphate. Our results highlight that the salvage pathway mediated by the dNK is essential for early chloroplast development in rice.


Assuntos
Cloroplastos/enzimologia , Cloroplastos/metabolismo , Oryza/enzimologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Clorofila/metabolismo , Cloroplastos/patologia , Cloroplastos/ultraestrutura , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Mutação de Sentido Incorreto , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/ultraestrutura , Fenótipo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo , Ribossomos/metabolismo , Plântula/genética , Plântula/metabolismo
3.
Genome ; 51(2): 104-12, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18356944

RESUMO

The elongation of the cooked grain determines the cooking and eating quality of Basmati rice. The identification of stable quantitative trait loci (QTLs), especially those from non-Basmati types, will extend the genetic basis of the Basmati type and facilitate the breeding of high-quality varieties. A set of recombinant inbred lines derived from an indica x japonica hybrid was used to identify QTLs controlling the elongation ratio (ER), elongation index (EI), and water absorption (WA) of the cooked grain. Three ER QTLs on chromosomes 2, 4, and 12, two EI QTLs on chromosomes 2 and 5, and two WA QTLs on chromosomes 2 and 6 were detected. Four of these QTLs were validated using a set of established chromosome segment substitution lines. The genetic effect of qER-2 was explored in an analysis of segregating generations, using 8 newly developed simple sequence repeat markers. Two tightly linked loci (qER-2a and qER-2b) were identified on chromosome 2.


Assuntos
Culinária , Oryza/genética , Locos de Características Quantitativas , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Marcadores Genéticos , Recombinação Genética
4.
J Neuroimmunol ; 100(1-2): 98-101, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10695719

RESUMO

Although immunoglobulin G and free light (L) chains of oligoclonal origin in cerebrospinal fluid (CSF) are the most common immunologic abnormalities in multiple sclerosis (MS), it is unknown whether homologous CSF L chain sequences are present in different individuals with MS. Using Southern blotting, a particular kappa (kappa) L chain variable region (V) probe was recently found to hybridize to Vkappa cDNA from CSF B cells from almost one half of the MS patients tested but only 10% of normal or other neurologic disease controls [Zhou, S.-R., Maier, C.C., Mitchell, G.W., LaGanke, C.C., Blalock, J.E., Whitaker, J.N., 1998. A cross-reactive idiotope in cerebrospinal fluid cells in multiple sclerosis: further evidence for the role of myelin basic protein. Neurology 50, 411-417.] Here, we report that this likely results from remarkable sequence similarity in certain Vkappa from CSF B cells from different individuals with MS. The high degree of sequence homology even extended to all three complementarity determining regions (CDR) which in part form an antibody combining site. In addition, marked sequence homology was observed between the light chains from the MS patients and those from certain mouse antibodies against myelin basic protein (MBP). The results establish, in principle, that the same or very similar kappa light chain variable regions can be shared between CSF B lymphocytes from different individuals with MS as well as with certain antibodies against MBP.


Assuntos
Cadeias Leves de Imunoglobulina/genética , Região Variável de Imunoglobulina/genética , Esclerose Múltipla/genética , Esclerose Múltipla/imunologia , Sequência de Aminoácidos , Animais , Linfócitos B/imunologia , Variação Genética , Humanos , Camundongos , Dados de Sequência Molecular , Esclerose Múltipla/líquido cefalorraquidiano , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/imunologia , Homologia de Sequência de Aminoácidos
5.
Neurology ; 50(2): 411-7, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9484364

RESUMO

We wanted to find evidence of antibody to myelin basic protein (MBP) in patients with MS by detecting their shared usage of immunoglobulin genes. As demonstrated by the idiotopes (i.d.) of murine monoclonal antibody to peptides of MBP, there is limited use of the variable (V) region immunoglobulin genes for the immune response in mice to this encephalitogenic protein. Cross-reactive Ids have been detected across different murine strains and shared by T and B cells. One cross-reactive Id, designated as 845D3 Id, is located on the V region of kappa light chains of two murine monoclonal antibodies, one to MBP peptide 80-89 and the other to MBP peptide acetyl 1-9. To examine the occurrence of 845D3 Id in MS, we used the V region of a light chain (VL) of one of the monoclonal antibodies to probe the VL genes expressed in B cells in CSF of 50 patients (31 MS and 19 non-MS). The VL genes expressed in B cells found in CSF were amplified by polymerase chain reaction using universal human V-region primers. The 845D3 Id probe detected the Id+ V region in the CSF of 14 of 31 MS patients, 1 of 9 patients with other neurologic diseases, and 1 of 10 non-neurologic patients. The gene product was more common in but not restricted to CSF with oligoclonal bands. The presence in CSF of MS patients of a cross-reactive Id to different MBP peptides is indicative of an immune response to this encephalitogenic myelin protein in a segment of MS patients. These findings are also evidence for limited usage of V-region Ig genes in the immune response of humans to MBP and the possible importance of an Id network for MBP in demyelinating disease.


Assuntos
Idiótipos de Imunoglobulinas/líquido cefalorraquidiano , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/imunologia , Proteína Básica da Mielina/imunologia , Adulto , Animais , Anticorpos Monoclonais , Linfócitos B/imunologia , Reações Cruzadas , Primers do DNA , Feminino , Genes de Imunoglobulinas , Humanos , Idiótipos de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Cadeias kappa de Imunoglobulina/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Esclerose Múltipla/genética , Reação em Cadeia da Polimerase , Valores de Referência
6.
J Neuroimmunol ; 70(1): 15-20, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8862130

RESUMO

Active immunization with myelin basic protein (MBP) induces experimental allergic encephalomyelitis (EAE) in a variety of animal species, including rats and mice. We have previously described the ability of the newly described mouse lambda (lambda) variable (V) region V lambda x, to confer MBP reactivity to an Ab. In this report, we have evaluated the heavy (H) chain isotype distribution of V lambda x-bearing Abs in normal mouse serum. We demonstrate a biased H chain isotype association with V lambda x light (L) chains with a skewing towards gamma 2a and 2b isotypes. The IgG2a restriction in normal mouse Igs is even more evident in V lambda x-containing Abs that bind MBP. This was confirmed by the ability of purified polyclonal IgG2a Abs to bind MBP and the finding that most or all of the IgG2a Abs that bind MBP seem to harbor a V lambda x L chain. The specificity of naturally-occurring V lambda x-bearing Abs with MBP can be localized to a particular epitope encompassing residues 25-34 of the MBP molecule. Furthermore, virtually all of the reactivity of V lambda x-containing Abs with MBP peptide 25-34 is associated with the gamma 2a isotype. Collectively, these results suggest that the interaction of V lambda x with MBP seems to be facilitated by an association with gamma 2a which may reflect preferred VH usage by this isotype. Such unique pairing of particular H chains with V lambda x L chains in Abs that bind MBP may be indicative of a new B-cell component involved in the pathogenesis of EAE.


Assuntos
Anticorpos Heterófilos/imunologia , Reações Antígeno-Anticorpo , Cadeias Pesadas de Imunoglobulinas/análise , Região Variável de Imunoglobulina/análise , Cadeias lambda de Imunoglobulina/análise , Camundongos/imunologia , Proteína Básica da Mielina/imunologia , Animais , Anticorpos Heterófilos/química , Anticorpos Heterófilos/metabolismo , Reações Cruzadas , Epitopos/imunologia , Rearranjo Gênico de Cadeia Leve de Linfócito B , Humanos , Imunização , Imunoglobulina G/química , Imunoglobulina G/imunologia , Isotipos de Imunoglobulinas/imunologia , Camundongos Endogâmicos BALB C , Proteína Básica da Mielina/metabolismo , Coelhos , Especificidade da Espécie
7.
J Neurosci Res ; 45(4): 439-46, 1996 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8872904

RESUMO

The idiotype (Id) of T cells and possibly antibodies are involved in an Id network that may immunoregulate experimental allergic encephalomyelitis (EAE). Thus, the adoptive EAE in PL/J mice responding to myelin basic protein (MBP) peptide acetyl 1-9 can be modulated by monoclonal antibody (mAb) anti-Id generated by immunization with a peptide of inverted hydropathy to MBP peptide 1-9, designated as PBM 9-1. A cross-reactive Id between species can be recognized on the T cell receptor (TCR) of Vb8.2 restricted T cells in either PL/J mice or Lewis rats. The present study was undertaken to examine the vaccine effect of PBM 9-1 presented in the form of a multiple antigen peptide (MAP) to induce active immunity against active EAE in Lewis rats and active or adoptive EAE in PL/J mice. MAP-PBM 9-1 induced an antibody response in both Lewis rats and PL/J mice, but more in the former. A low level of anti-Id antibody, including a low level of reactivity with specific but not control T cells, was also detected in the sera collected before induction of or after recovery from EAE. Active immunization with MAP-PBM 9-1 had a protective effect on relapses of adoptive EAE in PL/J mice and could prevent active EAE in Lewis rats. A relationship was noted between the titer of serum anti-PBM 9-1 Ab and the protective effect of active immunization in Lewis rats. Although the mechanism of effect remains to be clarified, these results suggest that MAP-PBM 9-1 is a nonencephalitogenic candidate for protection against inflammatory demyelination.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/prevenção & controle , Proteína Básica da Mielina/imunologia , Fragmentos de Peptídeos/imunologia , Vacinação , Sequência de Aminoácidos , Animais , Formação de Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Divisão Celular/imunologia , Linhagem Celular/imunologia , Linhagem Celular/metabolismo , Feminino , Citometria de Fluxo , Cobaias , Humanos , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Proteína Básica da Mielina/farmacologia , Fragmentos de Peptídeos/farmacologia , Ligação Proteica/imunologia , Ratos , Ratos Endogâmicos Lew , Recidiva , Linfócitos T/citologia
8.
J Clin Invest ; 97(2): 486-92, 1996 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8567971

RESUMO

Myelin basic protein (MBP) is highly immunogenic and a known autoantigen capable of inducing experimental allergic encephalomyelitis (EAE), the animal model of multiple sclerosis. We have previously described a murine monoclonal antibody (mAb), F28C4, directed against the encephalitogenic MBP peptide acetyl (Ac) 1-9, which contains a V lambda x light chain. Considering the rarity of V lambda x usage, we determined whether other Abs having V lambda x light chains shared similar antigen (Ag) specificity. We screened a panel of V lambda x-containing monoclonal and polyclonal Abs, of unknown specificity for reactivity with MBP. All such Ab, but not heavy chain isotype matched controls, bound MBP but were not polyreactive with other potential self Ags. The binding of a recombinant form of V lambda x alone to MBP demonstrated the important contribution of the V lambda x light chain to the reaction. With the exception of mAb F28C4 which recognizes MBP Ac1-9, the epitope specificity of all other V lambda x-bearing Abs was localized to MBP residues 25-34. These results demonstrate a unique association between V lambda x expression and MBP reactivity. Given that V lambda x shares sequence homology with T cell receptors (TCR) from encephalitogenic T lymphocytes, these results imply a potential role for V lambda x in the pathogenesis of EAE.


Assuntos
Cadeias lambda de Imunoglobulina/imunologia , Proteína Básica da Mielina/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Afinidade de Anticorpos , Sequência de Bases , Primers do DNA/química , Mapeamento de Epitopos , Humanos , Idiótipos de Imunoglobulinas , Região Variável de Imunoglobulina/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular
9.
J Neuroimmunol ; 62(2): 147-52, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7499502

RESUMO

The post-translational modifications of myelin basic protein (MBP) in the form of citrullination and varying length of amino-terminus acylation may modify the biological functions and immunological features of MBP. Both modifications influence the reaction of antibodies and specific T cells recognizing MBP. The present study was undertaken to compare the encephalitogenicity of the citrullinated isomer of MBP (MBP-C8) with the unmodified isomer of MBP (MBP-C1) and to determine if the length of amino-terminal acylation of MBP peptide 1-21 altered an encephalitogenic epitope. MBP-C8, whether from patients with or without multiple sclerosis (MS), and MBP-C1 could induce active experimental allergic encephalomyelitis (EAE) in PL/J mice. A trend of reduced severity of EAE was observed in MBP-C8-injected animals. An increase in the length of amino-terminus fatty acid decreased the encephalitogenicity of MBP peptide 1-21 for both active and adoptive EAE in PL/J mice. Only lymph node cells sensitive to MBP peptide acetyl 1-21 and butyl 1-21 could transfer clinical EAE. In adoptive EAE, MBP peptides hexyl and octyl 1-21 induced moderate histopathological but no clinical change, whereas MBP peptide decyl 1-21 caused neither. A broadening in the antibody response could be detected in the sera of mice with active EAE induced by MBP-acylated peptides 1-21. Our findings demonstrate that encephalitogenicity is retained in the presence of citrullination but that the length of amino-terminus acylation diminishes the encephalitogenicity of MBP in the PL/J mouse.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Citrulina/metabolismo , Proteína Básica da Mielina/imunologia , Processamento de Proteína Pós-Traducional , Acilação , Animais , Encefalomielite Autoimune Experimental/etiologia , Humanos , Camundongos , Proteína Básica da Mielina/química , Proteína Básica da Mielina/metabolismo , Relação Estrutura-Atividade
10.
Int Immunol ; 6(12): 1865-74, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7696205

RESUMO

Superantigens, such as staphylococcal enterotoxins, activate T lymphocytes by linking MHC class II molecules on antigen presenting cells to the V beta element of the TCR. Through this effect on T cells, superantigens may influence the immune response and autoimmune disease. In fact, superantigens may activate or anergize cells involved in the production of experimental allergic encephalomyelitis. Lewis rats recognize an encephalitogenic epitope in myelin basic protein (MBP) residues 68-88 through an MHC class II I-A restricted process using TCR V beta 8.2. The F30 murine mAb reacts with an encephalitogenic idiotope (Id) on the TCR of V beta 8.2+ encephalitogenic Lewis rat T cells. In the present study it was demonstrated that the same mAb anti-Id inhibited the proliferation and IL-2 secretion induced by staphylococcal enterotoxins A, B and E in a V beta 8.2+ encephalitogenic Lewis rat T cell line specific for guinea pig MBP peptide 68-88. The mAb anti-Id did not inhibit the response of control T cells similarly derived but inhibited V beta 8.2- and recognizing MBP peptide 87-99. Control anti-Id failed to inhibit the response of either cell line. These findings imply that the specific antigen and superantigen react with TCR in a manner similar enough to be inhibited by the same anti-Id. The mechanism may involve the induction of anergy by the anti-Id, interference/steric hindrance by the reaction of anti-Id with TCR and possibly a little direct reaction of anti-Id with superantigens. Anti-Id directed immunotherapy may have a role in modulating the damage of inflammatory demyelination induced by both specific antigens and superantigens.


Assuntos
Anticorpos Monoclonais/imunologia , Encefalomielite Autoimune Experimental/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Superantígenos/imunologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Feminino , Immunoblotting , Interleucina-2/biossíntese , Ativação Linfocitária/imunologia , Dados de Sequência Molecular , Ratos , Ratos Endogâmicos Lew , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/biossíntese
11.
Immunomethods ; 5(2): 107-13, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7874434

RESUMO

We have written a computer program to aid in the identification of interaction sites between proteins. The program compares the hydropathic profiles of the two interacting proteins and reports sites, demonstrating an exact pattern of inverted hydropathy. If these regions are surface accessible in the folded proteins, they are considered putative binding or docking sites and can be tested as such. In this report, we apply this program to the localization of residues involved in the anti-idiotope of a monoclonal antibody (mAb), F30C7. The anti-idiotope of F30C7 partially resembles the structure of the peptide antigen, human myelin basic protein (MBP) acetyl 1-9, used to elicit the idiotope bearing mAbs (Ab1). The sequences of F30C7 variable regions are compared to the variable regions of Ab1, as well as to the peptide antigen used to elicit F30C7. Sites of hydropathic complementarity in F30C7 with Ab1 that also have sequential homology with MBP 1-9 were located, and a synthetic peptide designed from these sequences was found to structurally resemble MBP 1-9 in that it: (i) inhibited Ab1 binding to MBP 1-9 and (ii) partially inhibited the binding of F30C7 to Ab1. Thus the portion of the anti-idiotope of F30C7 resembling MBP 1-9 was determined with the aid of this program. Other hits between F30C7 and Ab1 also occurred, and future studies will determine whether or not these sites might further contribute to the anti-idiotope.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Idiótipos de Imunoglobulinas/imunologia , Sequência de Aminoácidos , Anticorpos Anti-Idiotípicos/química , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Sequência de Bases , Ligação Competitiva/imunologia , Ensaio de Imunoadsorção Enzimática , Idiótipos de Imunoglobulinas/química , Região Variável de Imunoglobulina/química , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
12.
Immunomethods ; 5(2): 136-47, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7533043

RESUMO

In this article we review the field of idiotype (Id) network and experimental allergic encephalomyelitis, focusing on the generation of monoclonal antibody anti-Id by using complementary peptide and the investigation of anti-Id immunoregulatory effects on immune responses of B and T cells to specific myelin basic protein peptides in vitro and in vivo.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Doenças Autoimunes/imunologia , Idiótipos de Imunoglobulinas/imunologia , Proteína Básica da Mielina/imunologia , Peptídeos/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Doenças Autoimunes/prevenção & controle , Sequência de Bases , Dados de Sequência Molecular
13.
J Immunol ; 153(5): 2340-51, 1994 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-7519648

RESUMO

Encephalitogenic T cells of both PL/J mice and Lewis rats are restricted by TCR V beta 8.2, although they recognize different epitopes in the myelin basic protein (MBP) molecule. We sought the presence of a cross-reactive idiotope (Id) in encephalitogenic T cells of Lewis rats by examining the effects of mAb F30 anti-Id, which recognized a TCR Id in PL/J T cells, on the encephalitogenic LR88L1 cell line derived from Lewis rats and specific for guinea pig MBP peptide 68-88. The LR88L1 cells were I-A restricted and TCR V beta 8.2+, and their proliferation and secretion of IL-2 and TNF-alpha induced by guinea pig MBP peptide 68-88 was inhibited by mAb F30 anti-Id. As shown by FACS analysis and by immunoprecipitation of TCR from radiolabeled LR88L1 cell lysates, the F30 anti-Id bound to the TCRs of V beta 8.2+ LR88L1 cells. In addition, TCR sequences in the F30+ population of LR88L1 cells were the same as those of encephalitogenic Lewis rat T cells published previously. The F30+ LR88L1 cells showed reduced encephalitogenicity compared with F30- or unsorted LR88L1 cells. The mechanism for this reduction by anti-Id probably resulted from the induction of anergy, in that IL-2 reversed the anti-Id effect. The control LR99L1 T cell line, also encephalitogenic, but specific for MBP peptide 87-99 and I-E, and not TCR V beta 8.2 restricted, failed to react with, or have its cytokine secretion inhibited by, mAb F30 anti-Id. These results demonstrate an interspecies cross-reactive Id expressed in common by encephalitogenic T cells that share a similar TCR, although they differ in MBP epitope specificity. These findings suggest that a common Id restricted by TCR, but less restricted by the encephalitogenic epitope, and recognized by the Id-bearing autoreactive T cells may represent an immunotherapeutic approach for treating autoimmune demyelinating diseases.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Encefalomielite Autoimune Experimental/imunologia , Proteína Básica da Mielina/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Sequência de Bases , Linhagem Celular , Reações Cruzadas , Primers do DNA/química , Epitopos , Feminino , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Idiótipos de Imunoglobulinas , Interleucina-2/biossíntese , Ativação Linfocitária , Camundongos , Dados de Sequência Molecular , Ratos , Ratos Endogâmicos Lew , Receptores de Antígenos de Linfócitos T alfa-beta/química , Fator de Necrose Tumoral alfa/biossíntese
14.
J Immunol ; 153(3): 1132-40, 1994 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-7517973

RESUMO

The fine specificity of mAb F28C4 to myelin basic protein (MBP), acetyl residues 1-9, has been compared with the previously described specificity of an encephalitogenic T cell clone, PJR-25. F28C4 has been found to express a cross-reactive idiotope (CRI) that is shared with MBP acetyl peptide 1-9-specific TCR. The CRI seems to be located at or near the Ag-combining site of F28C4 and the TCR and, thus, might possibly result from overlapping epitope specificity. We tested the fine epitope specificity of F28C4 by using alanine-substituted peptide analogues and found that residues critical for TCR recognition, Cln3 and Pro6, are also necessary for F28C4 recognition. By using nuclear magnetic resonance, we found that the MBP acetyl peptide 1-9 binds F28C4 in an extended conformation and that the central residues are more tightly bound than the terminal residues, much like the MBP-TCR interaction. Furthermore, sequence homology (75% overall) was found between the regions that contained CDR3 of F28C4 VL and VH and the VDJ junction of the TCR V beta. This homology is not shared by other Ig CDR3 regions and arises, in part, because F28C4 uses an unusual V lambda light chain, V lambda x. Thus, F28C4 shares a CRI with the TCRs, possibly as a result of having similar fine epitope specificity and sequence homology. The anti-CRI mAb can down-modulate experimental allergic encephalomyelitis; thus, it is possible that Abs that are similar to F28C4 may play an important immunoregulatory role in experimental allergic encephalomyelitis in vivo.


Assuntos
Anticorpos Monoclonais/imunologia , Encefalomielite Autoimune Experimental/imunologia , Cadeias lambda de Imunoglobulina/imunologia , Proteína Básica da Mielina/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Especificidade de Anticorpos , Sequência de Bases , Primers do DNA/química , Epitopos , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Genes de Imunoglobulinas , Cadeias lambda de Imunoglobulina/química , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Proteína Básica da Mielina/química , Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/química , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
15.
Clin Immunol Immunopathol ; 70(3): 251-9, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7508836

RESUMO

The present study was undertaken to compare the features of monoclonal antibody (mAb) anti-idiotope (Id) induced by complementary peptides, synthesized on the basis of inverted hydropathy for a myelin basic protein (MBP) peptide, or by conventional methodology using Id-bearing antibodies to the same MBP peptide as immunogen. The six reagents studied consisted of mAbs reactive with MBP peptide acetyl 1-9 and MBP peptide 80-89 and anti-Id reagents against these two mAbs prepared by either the complementary peptide or the conventional approach. ELISA, immunoblotting, immunoinhibition of hybridoma cell production of Id-bearing mAb to MBP, and FACS indicated that the anti-Ids generated by either technique were similar although existing in a range reflecting biologic phenomena. mAbs anti-Id prepared by either method continued to show an IgM isotype preference, possibly related to technical considerations, and continued to recognize a cross-reactive Id on the kappa light chain of the mAbs to MBP peptides acetyl 1-9 and 80-89. There was no indication that the anti-Ids prepared by the complementary peptide approach were restrictive or selective in a manner different from those made by the conventional approach.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais/imunologia , Proteína Básica da Mielina/imunologia , Peptídeos/imunologia , Sequência de Aminoácidos , Animais , Formação de Anticorpos , Especificidade de Anticorpos , Antígenos de Superfície/imunologia , Células Clonais , Epitopos/análise , Humanos , Hibridomas , Idiótipos de Imunoglobulinas/imunologia , Camundongos , Dados de Sequência Molecular
16.
J Neuroimmunol ; 46(1-2): 235-43, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7689590

RESUMO

A cross-reactive idiotope (CRI) has been previously described on monoclonal antibodies (mAbs) specific for encephalitogenic peptides from myelin basic protein (MBP). The anti-CRI mAb, F25F7, binds an idiotope (Id) localized to the light chains of an anti-MBP peptide 1-9 mAb, denoted F23C6, and an anti-MBP peptide 80-89 mAb, denoted 845D3. It is the purpose of this study to further delineate the CRI being recognized by F25F7. To this end, we have found a structural correlation between the CRI and the antigen, a small synthetic peptide, denoted PBM 9-1, used to elicit the anti-Id mAb. Sequence comparison between the light chain of F23C6 and PBM 9-1 reveals a region of homology in CDR 2/FWK 3. The configuration of this site in the VL, as determined by comparison with a mAb, HyHEL-10, whose structure has been determined and is 97% homologous to the light chain of F23C6, conforms to the rules used to define antigenic determinants or Ids. A synthetic peptide having the F23C6 VL CDR 2/FWK 3 sequence inhibited the binding of F25F7 to F23C6 and 845D3. Taken together, these data suggest the Id recognized by F25F7 is defined, in part, by the PBM 9-1-like sequence of F23C6.


Assuntos
Anticorpos Anti-Idiotípicos/química , Anticorpos Monoclonais/química , Idiótipos de Imunoglobulinas/imunologia , Proteína Básica da Mielina/imunologia , Sequência de Aminoácidos , Anticorpos Anti-Idiotípicos/genética , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Sequência de Bases , Epitopos , Genes de Imunoglobulinas , Idiótipos de Imunoglobulinas/genética , Cadeias kappa de Imunoglobulina/genética , Modelos Moleculares , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/química , Estrutura Secundária de Proteína , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
17.
J Neuroimmunol ; 46(1-2): 91-6, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7689598

RESUMO

The citrullination and N-terminus acylation of myelin basic protein (MBP) increases the heterogeneity among the MBP isoforms. The present study was undertaken to further characterize the immune response to the citrullinated form (C8) of MBP as well as to the variably acylated N-terminus of MBP. Six well-characterized murine monoclonal antibodies (mAbs) to human MBP-C8 or MBP peptides (four mAbs to MBP acetyl 1-9, one mAb to MBP 10-19 and one mAb to MBP 80-89), one murine T cell line (PL11) to human MBP peptide acetyl 1-9 and one Lewis rat T cell line (RT-1) to guinea pig (GP) MBP peptide 68-88 were used to assess reactivity with MBP-C1, MBP-C8, and MBP peptides including a series of MBP peptide 1-21 containing 0, 2, 4, 6, 8 or 10 carbon fatty acids. Enzyme-linked immunosorbent assay (ELISA) results revealed that all of the mAbs reacted with human MBP-C1 and MBP-C8 except anti-MBP 10-19 and anti-MBP-C8. The former reacted only with MBP-C1 and the latter only with MBP-C8. The presence and length of acylation of MBP peptide 1-21 modified reactivity. Three mAbs to MBP acetyl 1-9 reacted only with acetyl 1-21, and one mAb anti-MBP actyl 1-9 reacted with all of MBP 1-21 preparations whether acylated or not. mAb anti-MBP-C8 generally reacted better with acylated MBP 1-21 having longer fatty acids. The PL11 T cell line strongly proliferated to human MBP-C1, MBP-C8 and MBP acetyl 1-9, responded, but less well, to MBP 1-21 with longer fatty acids and failed to respond to nonacylated MBP peptide 1-21. The RT-1 cell line responded strongly to GP MBP peptide 68-88, marginally to MBP-C8 and failed to respond to MBP-C1 or any of the other MBP peptides. Specific immune responses to different MBP charge isomers and different N-terminal acylating groups of MBP may play a role in immune-mediated demyelination.


Assuntos
Proteína Básica da Mielina/imunologia , Acilação , Anticorpos Monoclonais/imunologia , Citrulina/química , Epitopos , Humanos , Ativação Linfocitária , Proteína Básica da Mielina/química , Peptídeos/imunologia , Processamento de Proteína Pós-Traducional , Relação Estrutura-Atividade
18.
J Immunol ; 150(4): 1629-42, 1993 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-7679432

RESUMO

Acetylated peptide 1-9 from human myelin basic protein induces experimental allergic encephalomyelitis in PL/J mice through I-Au and TCR V beta 8.2. Murine mAb anti-Id directed against murine mAb to myelin basic protein peptide acetyl 1-9 was examined for effects on in vitro and in vivo T cell activities. Certain anti-Id, generated in PL/J mice, inhibited Ag-specific proliferation and IL-2 production and precipitated surface receptors having features of the TCR. The idiotypic features of TCR recognition were demonstrated by showing that binding of anti-Id to the TCR could be blocked by anti-TCR alpha beta and anti-TCR V beta 8.1-8.2 but not by murine Ig or anti-TCR V beta 17a. In addition, the anti-Id did not react with TCR V beta 8.2 transgenically inserted into MRL+/+ mice. One anti-Id was also capable of lessening clinical disease activity in the adoptive passive transfer model of experimental allergic encephalomyelitis in PL/J mice. These results indicate that anti-Id may recognize a cross-reactive Id on T cells, presumably on the TCR, responsive to the same I-Au-restricted encephalitogenic myelin basic protein peptide in PL/J mice. The selective development of anti-Id and their effect on T cell-mediated tissue damage provide a method for applying specific anti-Id antibodies to modify experimental and, possibly, spontaneous diseases of autoimmune demyelination.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Encefalomielite Autoimune Experimental/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular , Encefalomielite Autoimune Experimental/prevenção & controle , Imunização Passiva , Interleucina-2/farmacologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Proteína Básica da Mielina/química , Proteína Básica da Mielina/imunologia , Receptores de Antígenos de Linfócitos T/imunologia
19.
Clin Immunol Immunopathol ; 63(1): 74-83, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1375543

RESUMO

In order to assess the role of idiotype (Id) and the anti-Id network in murine experimental autoimmune encephalomyelitis (EAE), Id-bearing monoclonal antibodies (mAb) to human myelin basic protein (MBP) peptide acetyl 1-9, as well as mAb anti-Id, were developed in EAE-susceptible PL/J mice (H-2u). These mice recognize MBP residues acetyl 1-9 as an encephalitogenic determinant. Reactivities of PL/J Id-bearing mAbs to MBP and to MBP peptides were identical to those of mAbs generated against the same MBP peptide in EAE-resistant BALB/c mice (H-2d), even though isotypes of the mAbs differed. By using an inhibitory ELISA and immunoblotting, it was demonstrated that one PL/J mAb anti-Id recognized a public or framework Id, whereas another PL/J mAb-anti Id was directed to a private Id more restricted to the paratopic site. Two Id-bearing PL/J mAbs shared a cross-reactive Id (IdX) on the light chain, and an interstrain IdX was present on both the heavy and light chains of mAbs raised in PL/J and BALB/c mice to the same MBP peptide. The PL/J mAb anti-Id was capable of cross-regulating the production of Id-bearing mAbs by hybridomas across murine strains. These findings suggest that a restrictive family of germ-line genes encode for these Id-bearing antibodies to MBP peptide, irrespective of whether the MBP peptide is encephalitogenic in the murine strain immunized. Manipulation of the Id network may provide a means for modifying autoimmune demyelinating diseases of the central nervous system.


Assuntos
Anticorpos Monoclonais/imunologia , Encefalomielite Autoimune Experimental/imunologia , Idiótipos de Imunoglobulinas/imunologia , Proteína Básica da Mielina/imunologia , Fragmentos de Peptídeos , Animais , Ligação Competitiva , Reações Cruzadas , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica , Hibridomas/metabolismo , Immunoblotting , Isotipos de Imunoglobulinas , Imunoglobulina M/biossíntese , Camundongos , Camundongos Endogâmicos
20.
J Neuroimmunol ; 36(2-3): 135-46, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1370666

RESUMO

An immunochemical analysis was conducted to compare the C1 isomer of human myelin basic protein (MBP) with the newly described and less cationic, citrullinated isomer of MBP referred to as C8. Ten polyclonal antisera directed at multiple epitopes or restricted regions of MBP were used in radioimmunoassays to examine MBP-C1 and MBP-C8. Antisera reactive with MBP peptide 1-14 clearly distinguished MBP-C1 from MBP-C8. Antisera to human MBP peptides 10-19 and 90-170, but not to MBP peptide 69-89, showed modest differences between MBP-C1 and MBP-C8. The MBP-C8s from multiple sclerosis (MS) and non-MS brain reacted essentially the same. With murine monoclonal antibodies and enzyme-linked immunosorbent assay (ELISA), differences between MBP-C8 and other isomers were shown for anti-MBP 10-19 but not for anti-MBP 1-9 or anti-MBP 80-89. These findings imply differences in sequence or conformation in the structure of MBP-C7 compared to MBP-C1, most notably near the amino terminus.


Assuntos
Citrulina/imunologia , Proteína Básica da Mielina/imunologia , Adulto , Animais , Humanos , Imunoquímica , Proteína Básica da Mielina/metabolismo , Processamento de Proteína Pós-Traducional , Coelhos , Ovinos
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