RESUMO
BACKGROUND: Atopic dermatitis (AD), asthma, and allergic rhinitis are associated diseases involved in the atopic march. The bronchial challenge test (BCT) is a tool that evaluates airway hyperresponsiveness in patients with asthma. This study aimed to evaluate whether a positive BCT result is useful in assessment of paediatric AD. METHODS: This retrospective case series included 284 patients with AD who had BCT results. Clinical information and laboratory parameters were reviewed, including AD severity (using the SCORing Atopic Dermatitis [SCORAD]), skin hydration, and transepidermal water loss. RESULTS: Of the 284 patients who had BCT, 106 had positive BCT results and 178 had negative BCT results. A positive BCT result was associated with a history of asthma (P<0.0005), sibling with asthma (P=0.048), serum immunoglobulin E (P=0.045), eosinophil count (P=0.017), and sensitisation to food allergens in the skin prick test (P=0.027). There was no association between a positive BCT result and personal allergic rhinitis, parental atopy, sibling allergic rhinitis or AD, skin prick response to dust mites, objective SCORAD score, skin hydration, transepidermal water loss, exposure to smoking, incense burning, cat or dog ownership, or AD treatment aspects (eg, food avoidance and traditional Chinese medicine). Logistic regression showed significant associations of a positive BCT result with a history of asthma (adjusted odds ratio=4.05; 95% confidence interval=1.92-8.55; P<0.0005) and sibling atopy (adjusted odds ratio=2.25; 95% confidence interval=1.03-4.92; P=0.042). CONCLUSIONS: In patients with paediatric AD, a positive BCT result was independently and positively associated with personal history of asthma and sibling history of atopy, but not with any other clinical parameters.
Assuntos
Testes de Provocação Brônquica/estatística & dados numéricos , Dermatite Atópica/fisiopatologia , Eczema/diagnóstico , Adolescente , Alérgenos/análise , Asma/complicações , Asma/fisiopatologia , Criança , Pré-Escolar , Dermatite Atópica/complicações , Eczema/etiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Razão de Chances , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Testes CutâneosRESUMO
Biomembranes assume nonlamellar structures in many cellular events, with the tendency of forming a nonlamellar structure quantified by the monolayer spontaneous curvature, C(0), and with many of these events involving the acts of Ca(2+). Despite this biologically important intimacy, how C(0) is affected by [Ca(2+)] is unknown. In this study, we use the X-ray diffraction technique and the reconstruction of electron density profiles to measure the C(0)s of a zwitterionic phospholipid, DOPE, and two anionic phospholipids, DOPA and 18 : 1 (9Z) cardiolipin, at temperatures from 20 °C to 40 °C and [Ca(2+)]s from 0 mM to 100 mM; these phospholipids are chosen to examine the contributions of the electric charge density per molecule. While showing a strong dependence on temperature, C(0,DOPE) is nearly independent of [Ca(2+)]. In contrast, C(0,DOPA) and C(0),cardiolipin are almost unresponsive to the temperature change but affected by the [Ca(2+)] variation; and C(0,DOPA) varies with [Ca(2+)] â¼1.5 times more strongly than C(0,cardiolipin), with the phase preferences of DOPA and cardiolipin shifting to the H(II) phase and remaining on the Lα phase, respectively, at [Ca(2+)] = 100 mM. From these observations, we reveal the effects of modulating the strength of the inter-headgroup repulsion and discuss the mechanisms underlying the phase behaviour and cellular functions of the investigated phospholipids. Most importantly, this study recognizes that the headgroup charge density is dominant in dictating the phase behaviour of the anionic phospholipids, and that the unique molecular characteristics of cardiolipin are critically needed both for maintaining the structural integrity of cardiolipin-rich biomembranes and for fulfilling the biological roles of the phospholipid.
Assuntos
Cálcio/metabolismo , Cardiolipinas/química , Ácidos Fosfatídicos/química , Fosfatidiletanolaminas/química , Temperatura , Cardiolipinas/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Modelos Moleculares , Conformação Molecular , Transição de Fase , Ácidos Fosfatídicos/metabolismo , Fosfatidiletanolaminas/metabolismoRESUMO
Manystudies have shown that kidney transplant recipients have a higher incidence of cancers when compared with general population. However, most data on the posttransplant malignancies (PTM) are derived from Western literature and large population-based studies are rare. There is also lack of information about the posttransplant cancer-specific mortality rate. We conducted a population-based study of 4895 kidney transplants between 1972 and 2011, with data from the Hong Kong Renal Registry. Patterns of cancer incidence and mortality in our kidney transplant recipients were compared with those of the general population using standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs) respectively. With 40 246 person-years of follow-up, 299 PTM was diagnosed. The SIR of all cancers was 2.94 (female 3.58 and male 2.58). Non-Hodgkin lymphoma (NHL), kidney, and bladder cancers had the highest SIRs. The overall SMR was 2.3 (female 3.4 and male 1.7) and the highest SMR was NHL. The patterns of PTM differ among countries. Increases in cancer incidence can now translate into similar increases in cancer mortality. NHL is important in our kidney transplant recipients. Strategies in cancer screening in selected patient groups are needed to improve transplant outcomes.
Assuntos
Transplante de Rim/efeitos adversos , Neoplasias/epidemiologia , Neoplasias/etiologia , Sistema de Registros , Adulto , Distribuição por Idade , Idoso , Estudos de Coortes , Intervalos de Confiança , Feminino , Hong Kong/epidemiologia , Humanos , Incidência , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Distribuição por Sexo , Análise de SobrevidaRESUMO
We report the second imported case of New Delhi metallo-beta-lactamase (NDM-1) Enterobacteriaceae encountered in Hong Kong soon after the patient's arrival in the territory for medical care. As NDM-1 is spreading throughout the world via international travel, being an international city, Hong Kong was always expected to encounter the same public health threat. This case also illustrates the importance of active surveillance of at-risk patients in preventing the spread of this 'superbug'.
Assuntos
Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/isolamento & purificação , beta-Lactamases/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Feminino , Hong Kong/epidemiologia , Humanos , Pessoa de Meia-Idade , ViagemRESUMO
AIM: Symptomatology and severity of atopic dermatitis (AD) can be objectively measured with equipment. This study aimed to compare skin measurements and investigate their correlations with various clinical severity scores. METHODS: Skin hydration (SH), transepidermal water loss (TEWL), pH, erythema, pigmentation, and ITA (individual typology angle) were measured (using Delfin, Courage + Khazaka, and Mettler Toledo equipment), and correlated with Patient-Oriented Eczema Measure (POEM, a short-term subjective-symptom score), Scoring Atopic Dermatitis (SCORAD, a short-term subjective-symptom and objective-sign score), Nottingham Eczema Severity Score (NESS, a long-term subjective-symptom score), Children Dermatology Life Quality Index (CDLQI, a short-term subjective-symptom score) with Spearman's rho coefficient. RESULTS: 80 sets of clinical scores from eczema patients (mean age: 10.8 ± 4.9 years; 44.6% male) were evaluated. The POEM, objective SCORAD, CDLQI correlated well with each other. Skin pH ranged from 4.3 to 7.0 (mean 5.7 ± 0.61). Skin pH was correlated with Objective SCORAD components, including area (rho = 0.269, p = .036), erythema (rho = 0.302, p = .018), and lichenification (rho = 0.365, p = .026) and with the usage frequency of topical antibiotics. Skin pH was also correlated with other skin measurements, including SH (Delfin equipment: rho = -0.38, p < .001). SH and TEWL as measured by Delfin equipment correlated better with a number of symptoms and signs than Courage + Khazaka equipment. Other clinical measurements including erythema, melanin, and skin color did not demonstrate strong correlations with clinical symptom scores. CONCLUSION: Skin pH (using Mettler Toledo), SH, and TEWL (using Delfin equipment) correlated well with various clinical symptomatology scores. Less acidic pH appears to be associated with worse clinical scores of symptomatology, and increase usage of topical antibiotics, These findings not only support the supplementary usage of equipment in aiding objective documentation of clinical symptomatology in eczema therapeutic research but also the advocacy of maintaining more acidic skin and avoiding alkaline soap and emollient products.
Assuntos
Eczema/patologia , Pele/química , Administração Tópica , Adolescente , Antibacterianos/administração & dosagem , Criança , Pré-Escolar , Dermatite Atópica/patologia , Eczema/psicologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Lactente , Masculino , Índice de Gravidade de Doença , Pele/metabolismoRESUMO
Serum samples from 50 Caucasian patients with osteosarcoma were tested for the presence of antibodies to osteosarcoma-associated antigens (OSAA) and typed for nine Gm markers. A highly significant association was found between Gm 3;5,13,14 and unresponsiveness to OSAA, and between 1,3,17;5,13,14,21 and responsiveness to OSAA. These results suggest the existence of complementary immune response genes which in the heterozygous condition permit a response to OSAA.
Assuntos
Mapeamento Cromossômico , Alótipos de Imunoglobulina/genética , Imunoglobulina G/genética , Osteossarcoma/genética , Formação de Anticorpos , Antígenos de Neoplasias/imunologia , Heterozigoto , Humanos , Alótipos de Imunoglobulina/imunologia , Osteossarcoma/imunologia , FenótipoRESUMO
Immune competence declines with advanced age in hamsters, as in other laboratory mammals and in humans. We found significant alterations in the functional parameters of different populations of immunocytes (natural killer cells, T cells, monocytes, and suppressor cells) in aging hamsters, beginning at approximately 14 mo of age. Natural killer cytotoxicity, phytohemagglutinin-induced lymphocyte stimulation, and monocyte chemotaxis were decreased in aging Lak:LvG(Syr) outbred hamsters. When old hamsters were given a single injection (5 mg/kg body wt) of isoprinosine, a chemical immune potentiator, these three immune parameters increased almost to the levels found in young adult hamsters but returned to pretreatment levels after 7 d. Suppressor cell activity for the lymphocyte response to phytohemagglutinin, which increased with age, was decreased after treatment. In old hamsters treated with weekly injections of isoprinosine, these four immunological parameters remained at or near the levels found in young adults.
Assuntos
Envelhecimento , Imunidade/efeitos dos fármacos , Inosina Pranobex/farmacologia , Inosina/análogos & derivados , Animais , Quimiotaxia de Leucócito/efeitos dos fármacos , Cricetinae , Citotoxicidade Imunológica/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Ativação Linfocitária/efeitos dos fármacos , Monócitos/imunologia , Fito-Hemaglutininas/farmacologia , Linfócitos T/imunologia , Linfócitos T Reguladores/imunologiaRESUMO
The in vitro effects of isoprinosine (ISO) on interleukin-2 (IL-2) production, the expression of Tac antigen (IL-2 receptor) on lymphocytes, and the ability of Leu 3(+) cells to absorb interleukin-1 (IL-1) were investigated in 10 patients with acquired immune deficiency syndrome (AIDS). In 9 of the 10 patients, production of IL-2 from mononuclear cells and Leu 3(+) cells was depressed; expression of Tac antigen on mononuclear cells and Leu 2(+) cells was found to be depressed in 9 of 10 patients. The ability of the Leu 3(+) lymphocytes to absorb IL-1 was depressed in all (four of four) patients studied. After ISO treatment, IL-2 production, Tac antigen expression and IL-1 absorption were restored to normal or near normal levels in most of the patients. These results suggest that ISO has an immunostimulating capacity in AIDS patients and that the potential of ISO in immune response restoration in AIDS patients deserves critical consideration.
Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Antígenos de Superfície/análise , Inosina Pranobex/farmacologia , Inosina/análogos & derivados , Interleucina-2/biossíntese , Receptores Imunológicos/análise , Adulto , Feminino , Humanos , Interleucina-1/metabolismo , Interleucina-2/metabolismo , Contagem de Leucócitos , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/classificação , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , Receptores de Interleucina-2 , Membro 7 da Superfamília de Receptores de Fatores de Necrose TumoralRESUMO
OBJECTIVES: To describe the microbiological characteristics of a cohort of patients with complicated parapneumonic effusion and empyema thoracis, and to identify the potential risk factors for adverse outcomes, with particular reference to the choice of empirical antibiotics, intrapleural fibrinolytics, adherence to management guidelines, and input from pulmonologists. DESIGN: Retrospective review. SETTING: Regional hospital, Hong Kong. PATIENTS: All patients with a diagnosis of complicated parapneumonic effusion/empyema thoracis admitted between January 2003 and June 2005. MAIN OUTCOME MEASURES: Microbiological characteristics, mortality, and surgery-free survival. RESULTS. There were 63 patients, with a mean age of 64 (standard deviation, 16) years and a male-to-female ratio of 45:18. The pleural fluid culture positivity rate was 68%; Streptococcus milleri (19%), Bacteroides (14%), Klebsiella pneumoniae (12%), and Peptostreptococcus (7%) were the most common organisms. Thirteen (21%) patients died during their index admission. Use of intrapleural fibrinolytics according to the guideline was associated with survival (P=0.001) while discordant initial antibiotic use was associated with mortality (P=0.002). Discordant initial antibiotic use was also independently associated with reduced surgery-free survival (P<0.001). Subgroup analysis showed that early intrapleural fibrinolytic use (within 4 days of diagnosis) was associated with decreased mortality (P<0.001), increased surgery-free survival (P=0.005), and shorter hospital stay (P=0.039). CONCLUSION: Organisms identified from complicated parapneumonic effusion and empyema thoracis differ from those giving rise to community-acquired pneumonia. In these patients, adherence to guidelines, early concordant antibiotic treatment, intrapleural fibrinolytics, and input from a pulmonologist were associated with improved outcomes.
Assuntos
Empiema Pleural/tratamento farmacológico , Empiema Pleural/microbiologia , Derrame Pleural/tratamento farmacológico , Derrame Pleural/microbiologia , Pneumonia Bacteriana/tratamento farmacológico , Adulto , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteroides/efeitos dos fármacos , Bacteroides/isolamento & purificação , Revisão de Uso de Medicamentos , Empiema Pleural/complicações , Empiema Pleural/mortalidade , Feminino , Fibrinolíticos/farmacologia , Fibrinolíticos/uso terapêutico , Fidelidade a Diretrizes , Hong Kong , Mortalidade Hospitalar , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Peptostreptococcus/efeitos dos fármacos , Peptostreptococcus/isolamento & purificação , Derrame Pleural/complicações , Derrame Pleural/mortalidade , Pneumonia Bacteriana/complicações , Pneumonia Bacteriana/mortalidade , Estudos Retrospectivos , Fatores de Risco , Streptococcus milleri (Grupo)/efeitos dos fármacos , Streptococcus milleri (Grupo)/isolamento & purificação , Análise de Sobrevida , Resultado do TratamentoRESUMO
Human-primate hybrid cell lines were established by fusion of African green monkey kidney cells (VERO) with lymphoblastoid cells from patients with infectious mononucleosis (IM)(IMK101) and from Burkitt's lymphoma culture (HR1K). Both Epstein-Barr virus (EBV)-specific antigens and EBV particle-containing cells increased in the hybrid lines (IMK1-1/VERO,HR1K/VERO). Treatment of the hybrids with 5-bromodeoxyuridine induced more antigen-positive and more virus-containing cells. EBV could be activated from IM lymphoblastoid cells by fusion of the lymphoblastoid cells with the VERO cells. The increase of viral antigens and virus particles may have been due to the cellular interaction between VERO cells and the lymphoblastoid cells or to a possible derepressor supplied by the VERO component of the hybrid. Virus derived from the HR1K cell line was replicated in the human-primate hybrid, but further investigation may be necessary to determine if it was identical to the EBV derived from the human cell line.
Assuntos
Linfoma de Burkitt/microbiologia , Herpesvirus Humano 4/crescimento & desenvolvimento , Mononucleose Infecciosa/microbiologia , Animais , Antígenos Virais , Bromodesoxiuridina/farmacologia , Linfoma de Burkitt/imunologia , Linhagem Celular , Haplorrinos , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Células Híbridas/microbiologia , Mononucleose Infecciosa/imunologia , Linfócitos/imunologia , Linfócitos/microbiologia , Replicação ViralRESUMO
Antibodies specific for membrane-associated antigens of human osteosarcoma cells were isolated from sera of 12 patients with osteosarcoma (OS). Affinity columns were prepared by coupling purified membrane antigens from cultured human OS cell lines (TE-85 or LM) to CBrN-activated Sepharose 4B. The antigens were prepared by discontinuous sucrose gradient ultracentrifugation, papain digestion, and DEAE column chromatography. Diluted serum was passed over the affinity columns, and the adsorbed proteins were eluted with 2.5 M MgCl2 (pH 6.5). Immunodiffusion, indirect immunofluorescence, and complement fixation were used to assay antibody activity in the eluate. Specific anti-OS activity was found in the immunoglobulin (Ig) fraction isolated from the sera of the 12 OS patients, as confirmed by blocking experiments. No anti-OS antibody activity was found in sera from healthy individuals or patients with breast carcinoma, clear cell liposarcoma, or leukemia in this study. The anti-OS activity of the isolated Ig from OS patients was abolished after absorption with cultured human OS cells from lines LM, TE-85, or G292 but not after absorption with cells from lines WI-38 (embryonic lung), TE-32 (rhabdomyosarcoma), CAMA-1 or SW527 (breast carcinoma), or M-14 (melanoma). Absorption with rabbit antihuman IgG but not with rabbit antihuman IgM immunobeads completely eliminated the antibody activity.
Assuntos
Anticorpos Antineoplásicos/isolamento & purificação , Osteossarcoma/imunologia , Especificidade de Anticorpos , Antígenos de Neoplasias/análise , Membrana Celular/imunologia , Células Cultivadas , Cromatografia de Afinidade , Testes de Fixação de Complemento , Imunofluorescência , Humanos , Imunodifusão , Técnicas de ImunoadsorçãoRESUMO
Sera from 8 patients with osteosarcoma and 64 normal individuals were examined by C1q and Raji cell radioimmunoassays for the presence of circulating immune complexes. Of the 8 patients with osteosarcoma, 6 had elevated levels of immune complexes in their sera. The elevated levels of immune complexes were demonstrated by both the C1q radioimmunoassay and the Raji cell radioimmunoassay. The amount of immune complexes was quantitated by Raji cell radioimmunoassay; the mean plus or minus the standard error of the amount of aggregated human IgG equivalent per milliliter of serum was 80.12+/-72.64 micrograms for patients with osteosarcoma and 23.07+/-6.2 micrograms for normal individuals. The blocking effect of sera from patients with osteosarcoma on lymphocyte cytotoxicity against cultured osteosarcoma cells (TE-85) was examined. The result indicated that sera with elevated amounts of immune complexes also had increased levels of blocking activity. Sera were fractionated to separate immune complexes from gamma-globulins. No free tumor-specific antibody could be detected in fractionated gamma-globulin fractions from 2 patients with osteosarcoma. The sera of these patients had high amounts of immune complexes and high blocking activities.
Assuntos
Complexo Antígeno-Anticorpo , Neoplasias Ósseas/imunologia , Osteossarcoma/imunologia , Anticorpos Antineoplásicos/análise , Especificidade de Anticorpos , Antígenos de Neoplasias/análise , Ligação Competitiva , Testes Imunológicos de Citotoxicidade , Humanos , Técnicas In Vitro , Linfócitos/imunologia , Radioimunoensaio/métodosRESUMO
New Zealand White rabbits were immunized with whole-cell suspensions of TE-85 cells (from a human osteosarcoma) maintained in tissue culture. RNA was extracted from the lymphoid tissues of the immunized animals. Normal human peripheral blood lymphocytes were pretreated with both the whole-cell immune RNA (IRNA) and the Sephadex column-eluted fractions of the whole-cell IRNA. Significant stimulation of the cytotoxic effect of the lymphocytes was observed following whole-cell IRNA pretreatment and pretreatment with peak III fractions eluted from the column. This increase in inhibition was observed whether the target cells were TE-85 (the immunizing cells), L.M. and M.Mc. (two unrelated osteosarcoma primary cell cultures), or TE-85-M-MSV cells (a cell line capable of producing a human osteosarcoma in immunosuppressed hamsters). No inhibition was observed when cells from other types of human tumors were used as target cells. The results suggested that the transferred immunity was directed against tumor-specific osteosarcoma antigens.
Assuntos
Antígenos de Neoplasias , Linfócitos/imunologia , Osteossarcoma/imunologia , RNA/imunologia , Técnicas de Cultura , Humanos , Imunidade/efeitos dos fármacos , Imunoterapia , Osteossarcoma/terapia , RNA/isolamento & purificação , RNA/farmacologia , RNA/uso terapêuticoRESUMO
Monoclonal antibodies (MoAbs) against human osteosarcoma cells were obtained by the production and cloning of hybrids resulting from the fusion of mouse myeloma cells P3 X 63Ag8.653 with spleen cells from partially purified, osteosarcoma-associated antigen (OSAA)-immunized BALB/c mice. OSAAs were isolated from the spent culture medium of a human osteosarcoma cell line (TE-85). Five hybrid clones were established and designated as OSA1, OSA2, OSA3, OSA4, and OSA5. OSA1 and OSA2 had similar activity. All 5 MoAbs reacted strongly with most osteosarcoma cell lines and with all osteosarcoma tissues tested but not with 10 tumor cell lines and 2 tumor tissues from other cancers. OSA3, OSA4, and OSA5 cross-reacted with a fibrosarcoma cell line, a colon cell line, and fibrosarcoma, respectively, as well as with a melanoma cell line. None of the MoAbs were reactive with activated normal human peripheral blood mononuclear cells (PBMC). Immunoprecipitation of membrane protein isolated from LM cells and TE-85 cells with the MoAbs OSA1 and OSA2 conjugated with Staphylococcus aureus yielded a molecule with molecular weight of approximately 92,000. No detectable membrane protein was precipitated when 125I-labeled membrane protein from pooled activated human PBMC and tumor cells of other histologic types were used in the immunoprecipitation.
Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/imunologia , Osteossarcoma/imunologia , Animais , Especificidade de Anticorpos , Antígenos de Neoplasias/análise , Linhagem Celular , Humanos , Camundongos , Camundongos Endogâmicos BALB CRESUMO
BACKGROUND: The human carcinoembryonic antigen (CEA), which is expressed in several cancer types, is a potential target for specific immunotherapy using recombinant vaccines. Previous studies have shown that when the CEA gene is placed into vaccinia virus, the recombinant vaccine (rV-CEA) can elicit T-cell responses in both rodents and non-human primates. PURPOSE: Our objective was to determine if rVCEA could elicit CEA-specific T-cell responses in humans with appropriate human leukocyte antigen (HLA) motifs. METHODS: Peripheral blood lymphocytes (PBLs) obtained from patients with metastatic carcinoma, both before and after vaccination with rV-CEA, were analyzed for T-cell response to specific 9- to 11-mer CEA peptides selected to conform to human HLA class I-A2 motifs. RESULTS: While little or no T-cell growth was seen from preimmunization PBLs of patients pulsed with CEA peptides and interleukin 2 (IL-2), T-cell lines were obtained from PBLs of patients after vaccination with one to three cycles of stimulation. Cytolytic T-cell lines from three HLA-A2 patients were established with a 9-amino acid peptide (CAP-1), and the CD8+/CD4+ double-positive T-cell line (V24T) was chosen for detailed analysis. When autologous Epstein-Barr virus (EBV)-transformed B cells were either incubated with CAP-1 peptide or transduced with the CEA gene using a retroviral vector, they were lysed by the V24T cell line, but allogeneic non-A2 EBV-transformed B cells were not. The SW403 human colon carcinoma cell line, which is CEA positive and HLA-A2 positive, was also lysed by the V24T cell line, while two non-HLA-A2 CEA-positive colon carcinoma cell lines were not. To further confirm the class I HLA-A2 restricted nature of the V24T cytotoxicity, the non-HLA-A2 SW837 CEA-expressing colon carcinoma cell line was infected with a recombinant vaccinia virus expressing the HLA class I-A2 gene, and it became susceptible to V24T lysis. Cells infected with vector alone were not lysed. CONCLUSIONS: This study demonstrates for the first time (a) the ability to generate a human cytolytic T-cell response to specific epitopes of CEA, (b) the class I HLA-A2 restricted nature of the T-cell mediated lysis, and (c) the ability of human tumor cells to endogenously process CEA to present a specific CEA peptide in the context of major histocompatibility complex for T-cell-mediated lysis. IMPLICATIONS: These findings have implications in the development of specific second-generation cancer immunotherapy protocols.
Assuntos
Antígeno Carcinoembrionário/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Epitopos Imunodominantes/imunologia , Linfócitos T/imunologia , Vaccinia virus/imunologia , Vacinas Virais/imunologia , Sequência de Aminoácidos , Carcinoma/imunologia , Neoplasias Colorretais/imunologia , Citometria de Fluxo , Humanos , Dados de Sequência Molecular , Vacinas Sintéticas/imunologiaRESUMO
BACKGROUND: Protein antigens are presented to cytotoxic T lymphocytes as small peptides (approximately 9-10 amino acids long) bound to class I molecules of the major histocompatibility complex. The identification of tumor-associated antigens and specific peptide epitopes (i.e., antigenic determinants) may be useful in the development of anticancer vaccines. The generation of a cytotoxic T-cell response to one peptide epitope (amino acids 146-154) of human prostate-specific antigen (PSA) has been reported. PURPOSE: Our aim was to identify novel PSA peptides capable of eliciting specific cytotoxic T-cell responses. METHODS: Candidate peptides were identified on the basis of the following criteria: 1) they contained consensus amino acid motifs for binding to HLA-A2, which is the most common type of class I molecule; 2) they lacked strong homology with PSA-related kallikrein proteins; and 3) they were capable of stabilizing HLA-A2 class I molecules on the surface of human T2 (transport deletion mutant) cells, which are defective in antigen presentation. T-cell lines capable of killing (i.e., lysing) T2 target cells that had been pulsed with specific PSA peptides were generated from three different males (two disease-free individuals and one patient with prostate cancer) by incubating peripheral blood mononuclear cells with the peptides and interleukin 2. Specific cell lysis was monitored by the release of radioactivity from target cells that had been labeled with [111In]oxyquinoline. RESULTS: Two novel PSA peptides capable of eliciting cytotoxic T-cell responses were identified; these peptides were designated PSA-1 (amino acids 41-150) and PSA-3 (amino acids 154-163). Four different cytotoxic T-cell lines were generated in response to these peptides-three against PSA-3 and one against PSA-1. Specific lysis of peptide-pulsed T2 cells by the T-cell lines was blocked by the addition of a monoclonal antibody directed against class I molecules. The T-cell lines were also capable of lysing PSA-positive, HLA-A2-positive LNCaP cells (human prostate carcinoma cells). The specificity of LNCaP cell lysis was shown by the following: 1) the inability of added human K562 (chronic myelogenous leukemia) cells to inhibit it, 2) the ability of added anti-HLA-A2 antibodies to block it, and 3) the inability of the T-cell lines to induce substantial lysis of PSA-negative, HLA-A2-positive human cancer cells. IMPLICATIONS: Our studies form a rational basis for the use of PSA peptides or recombinant vectors encoding PSA in the development of anticancer vaccine immunotherapy protocols for patients with prostate cancer.
Assuntos
Neoplasias Colorretais/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Proteínas de Neoplasias/imunologia , Antígeno Prostático Específico/imunologia , Neoplasias da Próstata/imunologia , Linfócitos T Citotóxicos , Linhagem Celular , Epitopos/imunologia , Citometria de Fluxo , Antígeno HLA-A2/metabolismo , Humanos , Técnicas In Vitro , Masculino , Dados de Sequência Molecular , Antígeno Prostático Específico/metabolismo , Ligação Proteica , Células Tumorais Cultivadas , Vaccinia virusRESUMO
The plasma membrane of a cloned line of TE-85 (human osteosarcoma) cells subcultured for the last 4 years was isolated. The isolation was by hypotonic swelling, cell homogenization, and discontinuous sucrose gradient ultracentrifugation for 16 hr. Tumor-specific water-soluble antigens were identified by limited papain digestion of the isolated plasma membrane. Fractionation by diethylamino-ethyl anion-exchange column chromatography yielded antigenic fractions that inhibited the reaction of immune serum (from an unrelated patient with osteosarcoma) with the plasma membrane of TE-85 cells in tissue culture by indirect immunofluorescence test. Microimmunodiffusion confirmed the specificity of the isolated antigen against the sera of other patients with osteosarcoma. The definition of the antigen fraction may permit evaluation of antigen-antibody interaction in tumor immunity.
Assuntos
Antígenos de Neoplasias/isolamento & purificação , Osteossarcoma/imunologia , Complexo Antígeno-Anticorpo , Linhagem Celular , Membrana Celular/enzimologia , Membrana Celular/imunologia , Membrana Celular/metabolismo , Centrifugação com Gradiente de Concentração , Cromatografia DEAE-Celulose , Células Clonais/enzimologia , Células Clonais/imunologia , Células Clonais/metabolismo , Ferritinas/metabolismo , Imunofluorescência , Humanos , Imunodifusão , Técnicas In Vitro , Métodos , Microscopia Eletrônica , Osteossarcoma/enzimologia , Osteossarcoma/metabolismo , Papaína/metabolismo , Rabdomiossarcoma/imunologiaRESUMO
Hormone-induced alkaline phosphatases in human osteosarcoma cells (LM) were extracted and purified. Characterization of the purified enzyme showed two distinct isoenzymes. One isoenzyme was heat labile, was homoarginine inhibited, and had the electrophoretic migration of alkaline phosphatase of human osseous origin. Immunodiffusion showed that this isoenzyme reacted positively only against anti-bone alkaline phosphatase antibodies. The second isoenzyme was heat stable, was inhibited by phenylalanie, and had the same electrophoretic migration as did alkaline phosphatase extracted from mature normal human placenta. This second isoenzyme had the same antigenicity as did the normal placental enzyme. Like the D-variant placental phenotype, this second isoenzyme was inhibited by L-leucine and ethylenediaminetetraacetic acid.