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1.
Work ; 75(1): 325-337, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36591684

RESUMO

BACKGROUND: Studies found that women with breast cancer struggle with significant physical and mental challenges that affect their participation in daily living, social and work activities. Although women express their need for rehabilitation, in Israel there has been scant research on the nature of these needs. OBJECTIVE: To examine the implications of breast cancer for Israeli women in terms of their quality of life, body function, activities and participation in all facets of life, including work. METHODS: The sample was composed of women diagnosed with breast cancer. The data were collected through: (a) an online electronic survey assessing cancer-related quality of life (QoL), function and disability, fatigue and sensory-motor functions, (n = 120) followed by (b) face-to-face interviews and assessments (n = 20), and a healthy control group (n = 61). RESULTS: Women with breast cancer reported significantly lower QoL compared to the healthy control group. They reported higher levels of disability in areas such as, cognition, mobility, upper extremity, as well as overall difficulties in self-care, doing routine household activities and return to work. Roughly one-third of the women did not return to work. Interestingly, our sample did not perceive a decline in terms of their social support or networks, the women stated that family and social support were major enabling factors. CONCLUSION: The results show that breast cancer has short and long-term functional effects on most facets of these women's life. The women's social support system served as an enabling factor. Many women expressed their frustration at the lack of rehabilitation services for their condition and needs in Israel.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Qualidade de Vida , Apoio Social , Zeladoria , Nível de Saúde
2.
Eur J Haematol ; 110(1): 99-108, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36208015

RESUMO

We assessed the humoral and cellular response to the fourth BNT162b2 mRNA COVID-19 vaccine dose in patients with CLL. A total of 67 patients with CLL and 85 age matched controls tested for serologic response and pseudo-neutralization assay. We also tested the functional T-cell response by interferon gamma (IFNγ) to spike protein in 26 patients. Two weeks after the fourth vaccine antibody serologic response was evident in 37 (55.2%) patients with CLL, 20 /22 (91%) of treatment naïve, and 9/32 (28%) patients with ongoing therapy, compared with 100% serologic response in age matched controls. The antibody titer increased by 10-fold in patients with CLL, however, still 88-folds lower than age matched controls. Predictors of better chances of post fourth vaccination serologic response were previous positive serologies after second, third, and pre-fourth vaccination, neutralizing assay, and treatment naïve patients. T-cell response improved from 42.3% before the fourth vaccine to 84.6% 2 weeks afterwards. During the time period of 3 months after the fourth vaccination, 14 patients (21%) developed COVID-19 infection, all recovered uneventfully. Our data demonstrate that fourth SARS-CoV-2 vaccination improves serologic response in patients with CLL to a lesser extent than healthy controls and induces functional T-cell response.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Humanos , Vacinas contra COVID-19 , RNA Mensageiro , Vacina BNT162 , Leucemia Linfocítica Crônica de Células B/terapia , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Antivirais
3.
Vaccines (Basel) ; 10(10)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36298458

RESUMO

The design of efficient vaccines for long-term protective immunity against pathogens represents an objective of utmost public health priority. In general, live attenuated vaccines are considered to be more effective than inactivated pathogens, yet potentially more reactogenic. Accordingly, inactivation protocols which do not compromise the pathogen's ability to elicit protective immunity are highly beneficial. One of the sentinel mechanisms of the host innate immune system relies on the production of reactive nitrogen intermediates (RNI), which efficiently inactivate pathogens. Peroxynitrite (PN) is a prevalent RNI, assembled spontaneously upon the interaction of nitric oxide (NO) with superoxide. PN exerts its bactericidal effect by via the efficient oxidation of a broad range of biological molecules. Furthermore, the interaction of PN with proteins results in structural/chemical modifications, such as the oxidation of tryptophan, tyrosine, and cysteine residues, as well as the formation of carbonyl, dityrosine, and nitrotyrosine (NT). In addition to their role in innate immunity, these PN-mediated modifications of pathogen components may also augment the antigenicity of pathogen peptides and proteins, hence contributing to specific humoral responses. In the study reported here, a novel approach for vaccine development, consisting of pathogen inactivation by PN, combined with increased immunity of NT-containing peptides, is implemented as a proof-of-concept for vaccination against the intracellular pathogen Francisella tularensis (F. tularensis). In vivo experiments in a murine model of tularemia confirm that PN-inactivated F. tularensis formulations may rapidly stimulate innate and adaptive immune cells, conferring efficient protection against a lethal challenge, superior to that elicited by bacteria inactivated by the widely used formalin treatment.

4.
Arch Toxicol ; 96(3): 859-875, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35032184

RESUMO

rVSV-ΔG-SARS-CoV-2-S is a clinical stage (Phase 2) replication competent recombinant vaccine against SARS-CoV-2. To evaluate the safety profile of the vaccine, a series of non-clinical safety, immunogenicity and efficacy studies were conducted in four animal species, using multiple doses (up to 108 Plaque Forming Units/animal) and dosing regimens. There were no treatment-related mortalities or any noticeable clinical signs in any of the studies. Compared to unvaccinated controls, hematology and biochemistry parameters were unremarkable and no adverse histopathological findings. There was no detectable viral shedding in urine, nor viral RNA detected in whole blood or serum samples seven days post vaccination. The rVSV-ΔG-SARS-CoV-2-S vaccination gave rise to neutralizing antibodies, cellular immune responses, and increased lymphocytic cellularity in the spleen germinal centers and regional lymph nodes. No evidence for neurovirulence was found in C57BL/6 immune competent mice or in highly sensitive type I interferon knock-out mice. Vaccine virus replication and distribution in K18-human Angiotensin-converting enzyme 2-transgenic mice showed a gradual clearance from the vaccination site with no vaccine virus recovered from the lungs. The nonclinical data suggest that the rVSV-ΔG-SARS-CoV-2-S vaccine is safe and immunogenic. These results supported the initiation of clinical trials, currently in Phase 2.


Assuntos
Vacinas contra COVID-19/toxicidade , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , Cricetinae , Feminino , Glicoproteínas de Membrana/genética , Mesocricetus , Camundongos , Camundongos Endogâmicos C57BL , Coelhos , Suínos , Vacinação , Vacinas Sintéticas/toxicidade , Proteínas do Envelope Viral/genética
5.
Pathogens ; 10(8)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34451403

RESUMO

HLA transgenic mice are instrumental for evaluation of human-specific immune responses to viral infection. Mice do not develop COVID-19 upon infection with SARS-CoV-2 due to the strict tropism of the virus to the human ACE2 receptor. The aim of the current study was the implementation of an adenovirus-mediated infection protocol for human ACE2 expression in HLA transgenic mice. Transient pulmonary expression of the human ACE2 receptor in these mice results in their sensitisation to SARS-CoV-2 infection, consequently providing a valuable animal model for COVID-19. Infection results in a transient loss in body weight starting 3 days post-infection, reaching 20-30% loss of weight at day 7 and full recovery at days 11-13 post-infection. The evolution of the disease revealed high reproducibility and very low variability among individual mice. The method was implemented in two different strains of HLA immunized mice. Infected animals developed strong protective humoral and cellular immune responses specific to the viral spike-protein, strictly depending on the adenovirus-mediated human ACE2 expression. Convalescent animals were protected against a subsequent re-infection with SARS-CoV-2, demonstrating that the model may be applied for assessment of efficacy of anti-viral immune responses.

6.
Cell Rep ; 35(13): 109305, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34166618

RESUMO

The human leukocyte antigen (HLA)-bound viral antigens serve as an immunological signature that can be selectively recognized by T cells. As viruses evolve by acquiring mutations, it is essential to identify a range of presented viral antigens. Using HLA peptidomics, we are able to identify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-derived peptides presented by highly prevalent HLA class I (HLA-I) molecules by using infected cells as well as overexpression of SARS-CoV-2 genes. We find 26 HLA-I peptides and 36 HLA class II (HLA-II) peptides. Among the identified peptides, some are shared between different cells and some are derived from out-of-frame open reading frames (ORFs). Seven of these peptides were previously shown to be immunogenic, and we identify two additional immunoreactive peptides by using HLA multimer staining. These results may aid the development of the next generation of SARS-CoV-2 vaccines based on presented viral-specific antigens that span several of the viral genes.


Assuntos
Antígenos Virais/imunologia , COVID-19/imunologia , COVID-19/virologia , Peptídeos/imunologia , SARS-CoV-2/imunologia , Apresentação de Antígeno , Antígenos Virais/metabolismo , Vacinas contra COVID-19 , Linhagem Celular , Epitopos de Linfócito T/imunologia , Células HEK293 , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Peptidomiméticos , SARS-CoV-2/genética , Linfócitos T
7.
Am J Trop Med Hyg ; 101(3): 580-584, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31287043

RESUMO

A previously healthy young man presented with a chronic cavitary pulmonary infection that began while in Goa, India. Burkholderia pseudomallei was cultured from sputum samples. The infection fully resolved after prolonged antibiotic treatment. Other than traveling during the monsoon season, extensive use of well-water for water-pipe smoking of cannabis was identified as a possible risk factor for infection. This is one of the first reports of travel-associated melioidosis from India. Genomic and immunological characterization suggested that the B. pseudomallei isolate collected from the reported case exhibited limited similarity to other B. pseudomallei strains.


Assuntos
Doenças Transmissíveis Importadas/diagnóstico , Melioidose/diagnóstico , Viagem , Adulto , Antibacterianos/uso terapêutico , Burkholderia pseudomallei/isolamento & purificação , Doenças Transmissíveis Importadas/microbiologia , Humanos , Índia , Israel , Masculino , Melioidose/tratamento farmacológico , Fatores de Risco , Escarro/microbiologia
8.
Toxins (Basel) ; 8(8)2016 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-27548219

RESUMO

Edema Factor (EF), the toxic sub-unit of the Bacillus anthracis Edema Toxin (ET) is a calmodulin-dependent adenylate cyclase whose detrimental activity in the infected host results in severe edema. EF is therefore a major virulence factor of B. anthracis. We describe a simple, rapid and reliable functional adenylate-cyclase assay based on inhibition of a luciferase-mediated luminescence reaction. The assay exploits the efficient adenylate cyclase-mediated depletion of adenosine tri-phosphate (ATP), and the strict dependence on ATP of the light-emitting luciferase-catalyzed luciferin-conversion to oxyluciferin, which can be easily visualized. The assay exhibits a robust EF-dose response decrease in luminescence, which may be specifically reverted by anti-EF antibodies. The application of the assay is exemplified in: (a) determining the presence of EF in B. anthracis cultures, or its absence in cultures of EF-defective strains; (b) evaluating the anti-EF humoral response in experimental animals infected/vaccinated with B. anthracis; and (c) rapid discrimination between EF producing and non-producing bacterial colonies. Furthermore, the assay may be amenable with high-throughput screening for EF inhibitory molecules.


Assuntos
Adenilil Ciclases/metabolismo , Antígenos de Bactérias/metabolismo , Bacillus anthracis/enzimologia , Toxinas Bacterianas/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Trifosfato de Adenosina/metabolismo , Bacillus anthracis/genética , Indóis/metabolismo , Cinética , Luciferases/metabolismo , Medições Luminescentes , Pirazinas/metabolismo , Reprodutibilidade dos Testes
9.
PLoS One ; 4(6): e5938, 2009 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-19529770

RESUMO

An important virulence strategy evolved by bacterial pathogens to overcome host defenses is the modulation of host cell death. Previous observations have indicated that Yersinia pestis, the causative agent of plague disease, exhibits restricted capacity to induce cell death in macrophages due to ineffective translocation of the type III secretion effector YopJ, as opposed to the readily translocated YopP, the YopJ homologue of the enteropathogen Yersinia enterocolitica Oratio8. This led us to suggest that reduced cytotoxic potency may allow pathogen propagation within a shielded niche, leading to increased virulence. To test the relationship between cytotoxic potential and virulence, we replaced Y. pestis YopJ with YopP. The YopP-expressing Y. pestis strain exhibited high cytotoxic activity against macrophages in vitro. Following subcutaneous infection, this strain had reduced ability to colonize internal organs, was unable to induce septicemia and exhibited at least a 10(7)-fold reduction in virulence. Yet, upon intravenous or intranasal infection, it was still as virulent as the wild-type strain. The subcutaneous administration of the cytotoxic Y. pestis strain appears to activate a rapid and potent systemic, CTL-independent, immunoprotective response, allowing the organism to overcome simultaneous coinfection with 10,000 LD(50) of virulent Y. pestis. Moreover, three days after subcutaneous administration of this strain, animals were also protected against septicemic or primary pneumonic plague. Our findings indicate that an inverse relationship exists between the cytotoxic potential of Y. pestis and its virulence following subcutaneous infection. This appears to be associated with the ability of the engineered cytotoxic Y. pestis strain to induce very rapid, effective and long-lasting protection against bubonic and pneumonic plague. These observations have novel implications for the development of vaccines/therapies against Y. pestis and shed new light on the virulence strategies of Y. pestis in nature.


Assuntos
Peste/microbiologia , Yersinia enterocolitica/metabolismo , Yersinia pestis/metabolismo , Animais , Antígenos de Bactérias/química , Proteínas de Bactérias/metabolismo , Feminino , Proteínas de Fluorescência Verde/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Peste/prevenção & controle , Vacinas , Virulência
10.
Cancer Res ; 65(14): 6435-42, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16024648

RESUMO

Specific immunotherapy of prostate cancer may be an alternative or be complementary to other approaches for treatment of recurrent or metastasized disease. This study aims at identifying and characterizing prostate cancer-associated peptides capable of eliciting specific CTL responses in vivo. Evaluation of peptide-induced CTL activity in vitro was done following immunization of HLA-A2 transgenic (HHD) mice. An in vivo tumor rejection was tested by adoptive transfer of HHD immune lymphocytes to nude mice bearing human tumors. To confirm the existence of peptide-specific CTL precursors in human, lymphocytes from healthy and prostate cancer individuals were stimulated in vitro in the presence of these peptides and CTL activities were assayed. Two novel immunogenic peptides derived from overexpressed prostate antigens, prostatic acid phosphatase (PAP) and six-transmembrane epithelial antigen of prostate (STEAP), were identified; these peptides were designated PAP-3 and STEAP-3. Peptide-specific CTLs lysed HLA-A2.1+ LNCaP cells and inhibited tumor growth on adoptive immunotherapy. Furthermore, peptide-primed human lymphocytes derived from healthy and prostate cancer individuals lysed peptide-pulsed T2 cells and HLA-A2.1+ LNCaP cells. Based on the results presented herein, PAP-3 and STEAP-3 are naturally processed CTL epitopes possessing anti-prostate cancer reactivity in vivo and therefore may constitute vaccine candidates to be investigated in clinical trials.


Assuntos
Antígenos de Neoplasias/imunologia , Epitopos de Linfócito T/imunologia , Imunoterapia Adotiva/métodos , Fragmentos de Peptídeos/imunologia , Neoplasias da Próstata/imunologia , Proteínas Tirosina Fosfatases/imunologia , Linfócitos T Citotóxicos/imunologia , Fosfatase Ácida , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Antígeno HLA-A2/genética , Antígeno HLA-A2/imunologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Camundongos Nus , Camundongos Transgênicos , Oxirredutases , Neoplasias da Próstata/terapia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Clin Cancer Res ; 11(13): 4955-61, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16000595

RESUMO

PURPOSE: Cryotherapy of localized prostate, renal, and hepatic primary tumors and metastases is considered a minimally invasive treatment demonstrating a low complication rate in comparison with conventional surgery. The main drawback of cryotherapy is that it has no systemic effect on distant metastases. We investigated whether intratumoral injections of dendritic cells following cryotherapy of local tumors (cryoimmunotherapy) provides an improved approach to cancer treatment, combining local tumor destruction and systemic anticancer immunity. EXPERIMENTAL DESIGNS: The 3LL murine Lewis lung carcinoma clone D122 and the ovalbumin-transfected B16 melanoma clone MO5 served as models for spontaneous metastasis. The antimetastatic effect of cryoimmunotherapy was assessed in the lung carcinoma model by monitoring mouse survival, lung weight, and induction of tumor-specific CTLs. The mechanism of cryoimmunotherapy was elucidated in the melanoma model using adoptive transfer of T cell receptor transgenic OT-I CTLs into the tumor-bearing mice, and analysis of Th1/Th2 responses by intracellular cytokine staining in CD4 and CD8 cells. RESULTS: Cryoimmunotherapy caused robust and tumor-specific CTL responses, increased Th1 responses, significantly prolonged survival and dramatically reduced lung metastasis. Although intratumor administration of dendritic cells alone increased the proliferation rate of CD8 cells, only cryoimmunotherapy resulted in the generation of effector memory cells. Furthermore, cryoimmunotherapyprotected mice that had survived primary MO5 tumors from rechallenge with parental tumors. CONCLUSIONS: These results present cryoimmunotherapy as a novel approach for systemic treatment of cancer. We envisage that cryotherapy of tumors combined with subsequent in situ immunotherapy by autologous unmodified immature dendritic cells can be applied in practice.


Assuntos
Carcinoma Pulmonar de Lewis/terapia , Crioterapia/métodos , Células Dendríticas/imunologia , Imunoterapia Adotiva/métodos , Melanoma Experimental/terapia , Metástase Neoplásica/prevenção & controle , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/patologia , Proliferação de Células/efeitos dos fármacos , Terapia Combinada , Feminino , Citometria de Fluxo , Receptores de Hialuronatos/imunologia , Interferon gama/imunologia , Interleucina-4/imunologia , Selectina L/imunologia , Masculino , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Metástase Neoplásica/imunologia , Receptores de Antígenos de Linfócitos T/genética , Análise de Sobrevida , Resultado do Tratamento
12.
Vaccine ; 22(11-12): 1390-4, 2004 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-15063561

RESUMO

Directed dissemination of Ag-specific CD8(+) T cells to infected organs or cancerous tissues is a prerequisite for optimal immunotherapy. Ag-specific CD8(+) T cells were quantitated in systemic and mucosal tissues after nasal, rectal, or cutaneous immunization with CTL epitope peptide and the adjuvant cholera toxin (CT). Mucosal and cutaneous immunization induced Ag-specific CD8(+) lymphocytes that were detectable in both mucosal and systemic compartments, suggesting a less strict distribution pattern than that known for B cells. However, optimal localization, activation and phenotype of these cells correlated with the route of immunization. In accordance with this observation, protection against a mucosal challenge with a virus expressing the CTL epitope was superior in mucosally-immunized animals.


Assuntos
Especificidade de Anticorpos/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunidade nas Mucosas/imunologia , Vacinas/imunologia , Adjuvantes Imunológicos , Animais , Toxina da Cólera/imunologia , Epitopos/imunologia , Imunização , Camundongos , Camundongos Endogâmicos C57BL , Mucosa/imunologia , Fenótipo , Distribuição Tecidual
13.
Immunol Lett ; 91(2-3): 119-26, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15019279

RESUMO

The effects of Fas-ligand (FasL) expression by tumor cells on their tumorigenicity and immunogenicity have been reported as opposite, contradictory results. In some systems the killing of Fas positive cytotoxic T-cells (CTL) by FasL expressing tumors resulted in increased tumorigenicity while in other systems tumors expressing FasL were eliminated by neutrophil mediated inflammation. In the present study, we investigated how FasL expression influences the low immunogenic Lewis lung carcinoma clone D122 and its highly immunogenic MHC I (H-2Kb) and B7-1 (CD80) transfectant 39.5-B7, by transfecting the human FasL (FasL) gene into these cells. Despite the fact that FasL-expressing cells kill effectively appropriate target cells (L1210-fas) compared to parental cells (D122) and low expressors (DFasL-33), these tumor cells were completely rejected in syngeneic mice (C57BL/6), but not in Fas mutant B6-MRL mice, suggesting that functional Fas receptor expression in the host was required to induce an anti-tumor mechanism. In addition, although FasL-expressing immunogenic tumor cells (39.5-B7-FasL 7) kill effectively target cells in vitro, both the transfectant and the mock transfectant (39.5-B7-pBabe) were rejected in syngenic mice. The sensitivity of FasL expressing tumor cells to lysis by CTLs was similar to that of FasL non-expressors. Therefore, these results indicate that FasL expression on immunogenic tumor cells does not affect their immunogenicity in vivo, as well as CTL functions in vitro.


Assuntos
Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/metabolismo , Regulação Neoplásica da Expressão Gênica , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Linfócitos T Citotóxicos/imunologia , Animais , Carcinoma Pulmonar de Lewis/genética , Proteína Ligante Fas , Humanos , Camundongos , Mutação/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linfócitos T Citotóxicos/citologia , Transfecção , Células Tumorais Cultivadas
14.
Cancer Gene Ther ; 11(3): 237-48, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14739939

RESUMO

Perforin/granzyme B- and Fas/FasL-mediated killing pathways are the main effector mechanisms of CTL and NK cells in antitumor immune responses. In this study, we investigated the relative role of these two lytic mechanisms in protection of the host from tumor progression, as well as spontaneous metastasis, using the D122 Lewis lung carcinoma and its gene-modified cells. Utilizing perforin knockout mice (B6-PKO) and Fas and FasL mutant (B6-MRL and B6-Smn) mice, we found that perforin expression in the host plays a crucial function in the prevention of metastasis. However, local tumor rejection of an H-2K(b) and B7-1 transfectant, 39.5-B7 cells, was not dependent either on perforin or Fas/FasL expression in vivo. In addition, CTL lysis of 39.5-B7 cells was independent of perforin and Fas/FasL interactions in 18-hour in vitro assays. We also confirmed that CD8 T-cells were responsible for rejecting 39.5-B7 local tumors, yet cytokines, TNF-alpha and gammaIFN were not involved in tumor rejection in vivo. Furthermore, blocking assays using caspase inhibitors (zVAD-fmk, zLETD-fmk and zLEHD-fmk) showed that, whereas caspase activation was partially required to induce 39.5-B7 lysis mediated by the perforin-dependent pathway, 39.5-B7 lysis by CTLs through the perforin-independent mechanism required caspase activation. Thus, these results suggested that perforin, Fas/FasL, gammaIFN and TNF-alpha independent lytic mechanisms, mediated by CD8 T cells, have a crucial role in rejection of 39.5-B7 cells in vivo. Caspase activation is a pre requisite for apoptosis of targets by CTLs.


Assuntos
Carcinoma Pulmonar de Lewis/imunologia , Glicoproteínas de Membrana/metabolismo , Linfócitos T Citotóxicos/imunologia , Animais , Apoptose , Proteínas Reguladoras de Apoptose , Antígeno B7-1/metabolismo , Inibidores de Caspase , Caspases/metabolismo , Linhagem Celular Tumoral , Inibidores de Cisteína Proteinase/farmacologia , Proteína Ligante Fas , Antígenos H-2/metabolismo , Antígeno de Histocompatibilidade H-2D , Interferon gama/antagonistas & inibidores , Células Matadoras Naturais/imunologia , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , Transplante de Neoplasias , Perforina , Proteínas Citotóxicas Formadoras de Poros , Ligante Indutor de Apoptose Relacionado a TNF , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
15.
J Clin Invest ; 110(4): 453-62, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12189239

RESUMO

The human milk fat globule membrane protein BA46 (lactadherin) is highly overexpressed in human breast tumors, making it a potential target for tumor immunotherapy. We have identified BA46-derived peptides that contain the motif recognized by the MHC class I molecule HLA-A2.1 and that are processed and presented by human breast carcinoma cells. In mice lacking normal class I molecules but expressing an HLA-A2.1/D(b)-beta2 microglobulin single chain (HHD mice), three peptides elicited specific CTL activity. Two of these peptides also stimulated cytotoxic activity in peripheral blood lymphocytes from HLA-A2.1-positive breast carcinoma patients. Adoptive transfer of HHD-derived bulk CTLs to nude mice bearing human breast carcinoma transplants reduced tumor growth. These peptides therefore represent naturally processed BA46-derived CTL epitopes that can be used in peptide-based antitumor vaccines.


Assuntos
Antígenos de Superfície/imunologia , Neoplasias da Mama/imunologia , Carcinoma/imunologia , Antígeno HLA-A2/genética , Proteínas do Leite/imunologia , Proteínas de Neoplasias/imunologia , Microglobulina beta-2/genética , Transferência Adotiva , Animais , Antígenos de Superfície/química , Antígenos de Superfície/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Carcinoma/genética , Carcinoma/metabolismo , Extratos Celulares/imunologia , Epitopos/imunologia , Feminino , Antígeno HLA-A2/metabolismo , Humanos , Camundongos , Camundongos Knockout , Camundongos Nus , Camundongos Transgênicos , Proteínas do Leite/química , Proteínas do Leite/metabolismo , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Peptídeos/imunologia , RNA Neoplásico/biossíntese , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/transplante , Células Tumorais Cultivadas
16.
J Immunol ; 168(6): 2803-10, 2002 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11884449

RESUMO

NK cells are able to kill virus-infected and tumor cells via a panel of lysis receptors. Cells expressing class I MHC proteins are protected from lysis primarily due to the interactions of several families of NK receptors with both classical and nonclassical class I MHC proteins. In this study we show that a class I MHC-deficient melanoma cell line (1106mel) is stained with several Ig-fused lysis receptors, suggesting the expression of the appropriate lysis ligands. Surprisingly, however, this melanoma line was not killed by CD16-negative NK clones. The lack of killing is shown to be the result of homotypic CD66a interactions between the melanoma line and the NK cells. Furthermore, 721.221 cells expressing the CD66a protein were protected from lysis by YTS cells and by NK cells expressing the CD66a protein. Redirected lysis experiments demonstrated that the strength of the inhibitory effect is correlated with the levels of CD66a expression. Finally, the expression of CD66a protein was observed on NK cells derived from patients with malignant melanoma. These findings suggest the existence of a novel class I MHC-independent inhibitory mechanism of human NK cell cytotoxicity. This may be a mechanism that is used by some of the class I MHC-negative melanoma cells to evade attack by CD66a-positive NK cells.


Assuntos
Antígenos CD/imunologia , Antígenos de Diferenciação/imunologia , Citotoxicidade Imunológica/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Células Matadoras Naturais/imunologia , Melanoma/imunologia , Antígenos CD/biossíntese , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação/biossíntese , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Moléculas de Adesão Celular , Células Cultivadas , Testes Imunológicos de Citotoxicidade , Antígenos de Histocompatibilidade Classe I/biossíntese , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Terapia de Imunossupressão , Células Matadoras Naturais/metabolismo , Ligantes , Melanoma/genética , Melanoma/metabolismo , Receptores de IgG/biossíntese , Receptores de IgG/deficiência , Receptores de IgG/genética , Transfecção , Células Tumorais Cultivadas
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