PAULO FRANCISCO RAMOS MARGARIDO
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Obstetrícia e Ginecologia, Faculdade de Medicina - Docente
SCGINEC-62, Hospital Universitário
LIM/58 - Laboratório de Ginecologia Estrutural e Molecular, Hospital das Clínicas, Faculdade de Medicina
SCGINEC-62, Hospital Universitário
LIM/58 - Laboratório de Ginecologia Estrutural e Molecular, Hospital das Clínicas, Faculdade de Medicina
2 resultados
Resultados de Busca
Agora exibindo 1 - 2 de 2
- B lymphocytes can be activated to act as antigen presenting cells to promote anti-tumor responses(2018) ROSSETTI, Renata Ariza Marques; LORENZI, Noely Paula Cristina; YOKOCHI, Kaori; ROSA, Maria Beatriz Sartor de Faria; BENEVIDES, Luciana; MARGARIDO, Paulo Francisco Ramos; BARACAT, Edmund Chada; CARVALHO, Jesus Paula; VILLA, Luisa Lina; LEPIQUE, Ana PaulaImmune evasion by tumors includes several different mechanisms, including the inefficiency of antigen presenting cells (APCs) to trigger anti-tumor T cell responses. B lymphocytes may display a pro-tumoral role but can also be modulated to function as antigen presenting cells to T lymphocytes, capable of triggering anti-cancer immune responses. While dendritic cells, DCs, are the best APC population to activate naive T cells, DCs or their precursors, monocytes, are frequently modulated by tumors, displaying a tolerogenic phenotype in cancer patients. In patients with cervical cancer, we observed that monocyte derived DCs are tolerogenic, inhibiting allogeneic T cell activation compared to the same population obtained from patients with precursor lesions or cervicitis. In this work, we show that B lymphocytes from cervical cancer patients respond to treatment with sCD40L and IL-4 by increasing the CD80(+)CD86(+) population, therefore potentially increasing their ability to activate T cells. To test if B lymphocytes could actually trigger anti-tumor T cell responses, we designed an experimental model where we harvested T and B lymphocytes, or dendritic cells, from tumor bearing donors, and after APC stimulation, transplanted them, together with T cells into RAG1(-/-) recipients, previously injected with tumor cells. We were able to show that anti-CD40 activated B lymphocytes could trigger secondary T cell responses, dependent on MHC-II expression. Moreover, we showed that dendritic cells were resistant to the anti-CD40 treatment and unable to stimulate anti-tumor responses. In summary, our results suggest that B lymphocytes may be used as a tool for immunotherapy against cancer.
- Lactate secreted by cervical cancer cells modulates macrophage phenotype(2019) STONE, Simone Cardozo; ROSSETTI, Renata Ariza Marques; ALVAREZ, Karla Lucia Fernandez; CARVALHO, Jesus Paula; MARGARIDO, Paulo Francisco Ramos; BARACAT, Edmund Chada; TACLA, Maricy; BOCCARDO, Enrique; YOKOCHI, Kaori; LORENZI, Noely Paula; LEPIQUE, Ana PaulaCervical cancer continues to be a public health problem in developing countries. Previous studies have shown that cervical cancer cells display markers of aerobic glycolysis, indicating that these tumors are likely to secrete lactate. Mostly, lactate is recognized as a molecule capable of suppressing immune responses, through inhibition of T cells, M phi s, and dendritic cells. We and others have previously shown that M phi s are frequent cells infiltrating cervical cancers with the ability to inhibit antitumor immune responses and promote tumor growth through angiogenesis. Here, we have tested the hypothesis that lactate, secreted by cervical cancer cells, can modulate M phi phenotype. First, we showed higher lactate plasma concentrations in patients with increasing cervical lesion grades, with maximum concentration in the plasma of cancer patients, which supported our hypothesis. We then inhibited lactate production in tumor cell spheroids established from cervical cancer derived cell lines, using the lactate dehydrogenase inhibitor, oxamate, prior to co-culture with monocytes. Lactate mediated part of the crosstalk between tumor cells and M phi s, promoting secretion of IL-1, IL-10, IL-6, and up-regulation of hypoxia induced factor-1 expression, and down-regulation of p65-NFB phosphorylation in M phi s. We also showed that M phi s from co-cultures treated with oxamate were better inducers of T cell activation. Of note, experiments performed with inhibition of the monocarboxylate transporters rendered similar results. Our data confirms the hypothesis that lactate, secreted by cervical tumor cells, influences the phenotype of tumor M phi s, promoting a suppressive phenotype.