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2.
Korean Journal of Immunology ; : 121-127, 1999.
Artigo em Coreano | WPRIM | ID: wpr-176071

RESUMO

Dendritic cells (DCs) are the most potent antigen presenting cells that can activate naive T cells. Mature DCs exress high levels of MHC and costimulatory molecules on their surface and have capacity to produce IL-12, a 75 kDa heterodimeric cytokine composed of p35 and p40 subunit. IL-12 is currently thought to be one of most critical determinants for skewing the immune response towards Th1. Expression of IL-12 in dendritic cells seems to be regulated by various stimuli including CD40L. In the present study we investigated expression of IL-12 in mature DCs, which were cultured from bone marrow cells in the presence of GM-CSF. Maturity of the DCs was confirmed by morphologic characteristics, immunophenotypes, and allostimulatory activities. Exprssion levels of IL-12 p40 in the DCs were measured by semi-quantitative RT-PCR. Increases in IL-12 p40 expression were observed after treatment with lipopolysaccharide (LPS), an anti-MHC class II monoclonal antibody, or an anti-CD40 monoclonal antibody. The most remarkable increases, however, were observed in the DCs treated with an anti-CD40 monoclonal antibody. These results support a previous notion that signals through CD40/CD40L interaction may be important for the production of IL-12 by DCs. Moreover, results of this study show a possibility of using monoclonal antibodies against CD40 molecules for preparing DCs producing high amount of IL-12, which can be used for anti-tumor or anti-viral immunotherapy.


Assuntos
Animais , Camundongos , Anticorpos Monoclonais , Células Apresentadoras de Antígenos , Células da Medula Óssea , Ligante de CD40 , Células Dendríticas , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Imunoterapia , Interleucina-12 , Linfócitos T
3.
Journal of the Korean Society for Microbiology ; : 667-674, 1997.
Artigo em Coreano | WPRIM | ID: wpr-213005

RESUMO

The T cell responses to hepatitis B surface antigen (HBsAg) were analyzed in acute hepatitis patients, chronic active hepatitis (CAH) patients and asymptomatic carriers. Neither proliferative responses nor substantial cytokine production of peripheral blood mononuclear cells (PBMC) in response to HBsAg was detected. For further studies, HBsAg- reactive T cell lines were prepared from PBMC of the hepatitis patients and asymptomatic carriers. No proliferative response of the T cell lines was observed. Interestingly, however, T cell lines obtained from acute hepatitis patients were found to produce IFN-r, but not IL- 4, in response to HBsAg stimulation, whereas T cell lines obtained from CAH patients and carriers were not. Results of this study suggest that HBsAg-reactive T cells producing Thl type cytokines may play an important role in the viral clearance during acute infections, while defects in those T cells may be responsible for the viral persistency.


Assuntos
Humanos , Linhagem Celular , Citocinas , Hepatite , Antígenos de Superfície da Hepatite B , Hepatite Crônica , Linfócitos T
4.
Korean Journal of Immunology ; : 29-38, 1997.
Artigo em Coreano | WPRIM | ID: wpr-117937

RESUMO

No abstract available.


Assuntos
Animais , Camundongos , Autoimunidade
5.
Korean Journal of Immunology ; : 513-524, 1997.
Artigo em Coreano | WPRIM | ID: wpr-42340

RESUMO

Anti-idiotype antibody (anti-id Ab) which recognizes idiotope in the variable region of immunoglobulin (Ig) can regulate Ab production by B cells in vivo and in vitro. Although it has been reported that anti-id Ab can suppress IgM production by lymphocytes or hybridoma cells without suppression of cell proliferation, the regulatory mechanism of anti-id Ab is not completely understood. We studied the effects of anti-id Ab on the production of IgG class anti-DNA Ab by hybridoma cells, on the proliferation of cells, and on the transcription levels of Ig genes. In contrast to suppressive effect of anti-id Ab on the production of IgM previously reported by others, stimulatory effects of anti-id Ab on the production of IgG by hybridoma cells as well as the proliferation of these .cells were observed. However, little effect of anti-id Ab on the transcription levels of Ig genes was observed. These results suggest that anti-id Ab can increase Ab production by stimulation of cell proliferation. Furthermore, these results suggest that the effect of anti-id Ab on the production of Ab may be determined by the difference in class of Ab produced by hybridoma cells following the treatment with anti-id Ab.


Assuntos
Formação de Anticorpos , Linfócitos B , Proliferação de Células , DNA , Genes de Imunoglobulinas , Hibridomas , Imunoglobulina G , Imunoglobulina M , Imunoglobulinas , Linfócitos
6.
Yonsei Medical Journal ; : 258-265, 1993.
Artigo em Inglês | WPRIM | ID: wpr-164592

RESUMO

We have investigated in vitro proliferative responses of peripheral blood mononuclear cells and productions of interferon-gamma and soluble interleukin-2 receptors by these cells from 6 patients with chronic active hepatitis B immediately before and 24 hours after a single intravenous injection of 100 mg of polyadenylic.polyuridylic acid. Cell proliferations were assessed by the technique of tritiated-thymidine incorporation and productions of interferon-gamma and soluble interleukin-2 receptors were measured by enzyme-linked immunosorbent assay. The administration of polyadenylic.polyuridylic acid to the patients has resulted in significant increases of in vitro proliferations of their peripheral blood mononuclear cells as well as productions of interferon-gamma by these cells. However, in vitro productions of soluble interleukin-2 receptors were not changed significantly. These results suggest that the enhanced cellular responses by polyadenylic.polyuridylic acid might be due to the increased sensitivity rather than the increased expression of cellular interleukin-2 receptor.


Assuntos
Adulto , Humanos , Masculino , Hepatite B/imunologia , Hepatite Crônica/imunologia , Imunidade Celular/efeitos dos fármacos , Interferon gama/biossíntese , Leucócitos Mononucleares/efeitos dos fármacos , Pessoa de Meia-Idade , Poli A-U/farmacologia , Receptores de Interleucina-2/biossíntese , Solubilidade
7.
Journal of Korean Medical Science ; : 187-191, 1993.
Artigo em Inglês | WPRIM | ID: wpr-195997

RESUMO

Our previous study revealed that mutations of the p53 gene were detected by cDNA sequencing in one of four (25%) primary gastric tumors and in five of six (83%) gastric cancer cell lines. It was of interest that all five cell lines established from metastatic lesions had p53 gene mutations, while the single cell line established from a primary tumor lacked an abnormality. Thus, the current study was initiated to determine the frequency of p53 mutations in 10 pairs of samples from primary gastric carcinomas and their lymph node metastases, in addition to morphologically normal gastric mucosa. In addition, we correlated the findings with other relevant molecular markers including the metastasis associated nm23-H1 gene and loss of heterozygosity (LOH) using multiple polymorphic markers for chromosome 17p and sequencing the entire open reading frame (ORF) of the p53 gene. Five of ten (50%) patients were constitutionally heterozygous for one or more 17p and/or p53 probes (pYNZ 22, BamHI RFLP; pMct35.1, Mspl RFLP; php53cl, Bg/II RFLP), while none had LOH at the 17p and/or p53. A Bg/II RFLP for analysis of possible nm23-H1 somatic allelic deletion revealed no LOH out of four informative cases. One paired sample demonstrated the substitution of valine for isoleucine at codon 41 (GTT to ATT) in both primary gastric tumor and metastasis. Another metastatic sample demonstrated the substitution of proline for threonine at codon 278 (CCT to C/ACT) in addition to a non-mutated codon, while only the wild-type p53 sequence was present in the paired primary gastric tumor tissue.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Humanos , Sequência de Bases , Deleção Cromossômica , DNA Complementar/química , Genes p53 , Dados de Sequência Molecular , Mutação , Metástase Neoplásica/genética , Polimorfismo de Fragmento de Restrição , RNA Mensageiro/análise , Neoplasias Gástricas/genética
8.
Journal of the Korean Society for Microbiology ; : 165-174, 1993.
Artigo em Coreano | WPRIM | ID: wpr-158244

RESUMO

No abstract available.


Assuntos
Animais , Camundongos , Formação de Anticorpos , Imunoglobulina E , Poli I-C
9.
Yonsei Medical Journal ; : 41-47, 1992.
Artigo em Inglês | WPRIM | ID: wpr-153232

RESUMO

The NK activity and ADCC of peripheral blood mononuclear cell were examined to evaluate the contribution of ADCC and NK activity to host immune response against lung cancer. The NK activity and ADCC were examined in 58 patients with primary lung cancer and 40 healthy volunteers as normal controls. The NK activity of patients with lung cancer was significantly subnormal, but ADCC was at a normal level. The NK activity was decreased in non-small cell lung cancer (NSCLC), but not in small cell lung cancer (SCLC) compared to normal controls. According to stage, the NK activity in stage II, III-M0 and III-M1 NSCLC showed low levels compared to that of stage I NSCLC, but there was no difference of NK activity in patients with SCLC. The NK activity was not affected by performance status. There was no significant difference of ADCC in patients with lung cancer according to cell type, stage and performance compared with that of normal controls. The NK activity and ADCC were not changed after chemotherapy and operation respectively.


Assuntos
Humanos , Citotoxicidade Celular Dependente de Anticorpos , Células Matadoras Naturais/imunologia , Neoplasias Pulmonares/imunologia , Estadiamento de Neoplasias
10.
Journal of Korean Medical Science ; : 110-115, 1992.
Artigo em Inglês | WPRIM | ID: wpr-161619

RESUMO

The molecular mechanisms of the carcinogenic process of gastric cancer have not been fully understood yet. In order to know whether c-Ha-ras gene is being involved in the process of gastric carcinogenesis, 8 gastric cancer cell lines, 8 cases of gastric cancer and same number of adjacent dysplasia were analyzed for the presence of mutation at codon 12, 13 and 61 of the c-Ha-ras gene by using polymerase chain reaction (PCR) and mutant-specific oligonucleotide hybridization. Point mutations at codon 12 of the c-Ha-ras gene were found in 2 out of 8 gastric cancer and dysplasia samples in one case, but we found no mutation at codon 13 or 61 of the c-Ha-ras gene. These results suggest that the frequency of mutation of the c-Ha-ras gene detected by sensitive PCR technique is low indeed, however it would be notable that such a genetic change has been detected in the dysplastic lesion of the gastric cancer patient.


Assuntos
Humanos , Sequência de Bases , Códon , Genes ras , Dados de Sequência Molecular , Mutação , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Neoplasias Gástricas/genética
13.
Yonsei Medical Journal ; : 143-152, 1992.
Artigo em Inglês | WPRIM | ID: wpr-146236

RESUMO

Recently, metastasis to N3 lymph nodes group was regarded as distant metastasis by the new TNM staging system due to poor overall survival. However, the 5-year overall survival rate of patients with metastasis to N3 groups was 34.5% after curative surgery. Moreover, in patients with metastasis to lymph node subgroups of #12, #13, #14, the overall 5-year survival rate increased upto 47.2% after curative resection and adjuvant chemotherapy. This was similar to that of the patients with metastasis to N1 and N2 lymph nodes groups. But in these highly tumor burden states, no survival benefit was found with the addition of immunotherapy to chemotherapy as we achieved in stage II and III. Therefore, we suggest that, at least, metastasis to #12, #13, #14 lymph nodes subgroups should not be categorized as a distant metastasis. And in these situations, active curative radical surgery with extended lymphadenectomy and adjuvant chemotherapy are recommended.


Assuntos
Adulto , Feminino , Humanos , Masculino , Quimioterapia Adjuvante , Metástase Linfática , Pessoa de Meia-Idade , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida
14.
Journal of the Korean Society for Microbiology ; : 239-251, 1992.
Artigo em Coreano | WPRIM | ID: wpr-218888

RESUMO

No abstract available.


Assuntos
Humanos , Anticorpos , Hanseníase
15.
Journal of the Korean Society of Plastic and Reconstructive Surgeons ; : 390-406, 1991.
Artigo em Coreano | WPRIM | ID: wpr-98420

RESUMO

No abstract available.


Assuntos
Humanos
16.
Journal of the Korean Cancer Association ; : 1-9, 1991.
Artigo em Coreano | WPRIM | ID: wpr-169599

RESUMO

No abstract available.


Assuntos
Animais , Camundongos
17.
Yonsei Medical Journal ; : 174-181, 1990.
Artigo em Inglês | WPRIM | ID: wpr-38645

RESUMO

The effects of polyadenylic.polyuridylic acid [poly(A).poly(U)] on in vitro proliferations of thymus and spleen cells from C57BL/6 mice were investigated. Mice were injected intravenously with 30 micrograms of poly(A).poly(U) or placebo. Two days later, thymus, spleen and peritoneal cells from these mice were prepared and cultured in pooled or non-pooled conditions. Cell proliferations were assessed by the technique of incorporation of tritiated thymidine. It has been revealed that the in vitro proliferations of thymus and spleen cells as well as the productions of interleukin-1 by peritoneal adhering cells and interleukin-2 by spleen cells were significantly enhanced in the cultures of cells from poly(A).poly(U)-treated mice. These enhancing effects were observed only in the cultures of pooled cells from mice whose genetic homogeneity is suspected. Furthermore, thymus cells from poly(A).poly(U)-treated mice acted as strong responder cells but not as stimulators in one way mixed cultures. Thus, the enhanced cellular responsiveness may be mediated by the increased production of cytokines and antigen recognitions of thymus-derived cells following activations via the adjuvant effect of poly(A).poly(U).


Assuntos
Feminino , Masculino , Camundongos , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Interleucina-1/biossíntese , Interleucina-2/biossíntese , Camundongos Endogâmicos C57BL , Poli A-U/administração & dosagem , Baço/citologia , Timo/citologia
18.
Yonsei Medical Journal ; : 357-366, 1988.
Artigo em Inglês | WPRIM | ID: wpr-176788

RESUMO

Though the malignancy of a tumor is generally postulated to be affected by the degree of differentiation of tumor cells, the relationship between differentiation and malignancy of tumors has not been clearly elucidated. Using in vitro established mouse(B16) and human(IGR3) melanoma cell lines, we performed various in vitro and in vivo experiments to clarify the relationship between melanogenicity and malignancy. High and low melanin-producing clones were selected from both cell lines by the limiting dilution technique and their melanogenicities were confirmed by the determination of melanin quantity and tyrosinase activity along with electron microscopic examination. Selected clones from both cell lines revealed that low melanin-producing clones showed a slightly broader chromosomal distribution, a shorter doubling time with a higher DNA synthesis and a greater colony forming capacity in semi-solid agar medium than those of high melanin-producing clones. The low melanin-producing clone derived from B16 also had a lower tumor-take dose and a more rapid tumor-growth rate than the high melanin-producing counterpart following transplantation into syngeneic mice. These results support the concept that the melanogenicity and other biological characteristics associated with malignancy are inversely related in malignant melanoma cells.


Assuntos
Humanos , Camundongos , Animais , Linhagem Celular , Melaninas/metabolismo , Melanoma/patologia , Melanoma Experimental/patologia , Camundongos Endogâmicos , Microscopia Eletrônica , Transplante de Neoplasias , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas/patologia , Ensaio Tumoral de Célula-Tronco
19.
Yonsei Medical Journal ; : 160-165, 1988.
Artigo em Inglês | WPRIM | ID: wpr-190443

RESUMO

The natural killer(NK) cell activity of mononuclear cells (MNC) from peripheral blood (PB) and synovial fluid (SF) of 40 rheumatoid arthritis(RA) patients was investigated by employing 51-chromium-(51Cr) release microcytotoxicity and single cell cytotoxicity assays against K562 target cells. It has been revealed that SF-MNC from RA patients showed a significantly lower NK activity than PB-MNC from the same patients and this might be due to an impaired target binding capacity of the effector cells and not due to a deficiency of active NK cells.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Artrite Reumatoide/imunologia , Radioisótopos de Cromo , Estudo Comparativo , Testes Imunológicos de Citotoxicidade/métodos , Citotoxicidade Imunológica , Técnicas In Vitro , Células Matadoras Naturais/imunologia , Pessoa de Meia-Idade , Líquido Sinovial/imunologia
20.
Korean Journal of Dermatology ; : 804-811, 1988.
Artigo em Coreano | WPRIM | ID: wpr-203683

RESUMO

This study was undertaken to investigate the immunological mechanism of Behqet s syndrome, considered to be important in the pathogenesis of the disease. Seventy- three patients with complete, incomplete and suspected types of Behget's syndrotne were tested for leukocyte migration ingibition factor(LIF), one of the lymphokines. The results were as follows : 1. There was no difference between the average LIF activity of all the patients and that of eontrol. 2. LIF activity of complete type, according to Shirnizus classification, was significaritly lower than the control value. 3. LIF activity of ocular type, according to Lehners classification, was signficantly lower than the control value. 4. LIF activity for patients with 4 clinical symptoms was well below the value for patients with less symptomes 5. For patients with single clinical symptom, LIF activity of complete type was well below the values of incomplete and suspected types. 6. In suspected and mucocutaneous types, LIF activity was low when the patients showed two clinical symptoms than one. Thus, LIF activity was low for patients with complete, ocular and neurological types and with multiple symptorns.


Assuntos
Humanos , Síndrome de Behçet , Classificação , Leucócitos , Linfocinas
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