Immunological Characteristics between αß TDC and γδ TDC Cells in the Spleen of Breast Cancer-Induced Mice / Características imunológicas entre células TDC αß e TDC γδ no baço de camundongos com câncer de mama induzido

Abstract Objective To evaluate the antitumoral role of γδ TDC cells and αβ TDC cells in an experimental model of breast cancer. Methods Thirty female Balb/c mice were divided into 2 groups: control group (n=15) and induced-4T1 group (n=15), in which the mice received 2 x 105 4T1 mammary tumor cell line. Following the 28-day experimental period, immune cells were collected from the spleen and analyzed by flow cytometry for comparison of αβ TDC (TCRαβ+ CD11c+MHCII+) and γδ TDC (TCRγδ+CD11c+MHCII+) cells regarding surface markers (CD4+ and C8+) and cytokines (IFN-γ, TNF-α, IL-12 and IL-17). Results A total of 26.53% of γδ TDC- control group (p<0.0001) - the proportion of αβ TDC was lower in splenic cells than γδ TDC; however, these 2 cell types were reduced in tumor conditions (p<0.0001), and the proportion of IFN-γ, TNF-α, IL-12 and IL-17 cytokines produced by γδ TDC was higher than those produced by αβ TDC, but it decreased under conditions of tumor-related immune system response (p<0.0001). Conclusion Healthy mice engrafted with malignant cells 4T1 breast tumor presented TDC with γδ TCR repertoire. These cells express cytotoxic molecules of lymphocytes T, producing anti-tumor proinflammatory cytokines.

Resumo Objetivo Esclarecer o possível papel antitumoral das células TDC γδ e TDC αβ em um modelo experimental de câncer de mama. Métodos Trinta baços de camundongos Balb/c analisados por citometria de fluxo, separados entre grupo controle (n=15) e o grupo tumoral induzido por 4T1 (n=15). Resultados Presença de 26,53% de TDC γδ nos camundongos do grupo controle (p<0,0001), proporção de TDC αβ menor em células esplênicas do que TDC γδ; no entanto, estes dois tipos de células são reduzidos emcondições tumorais (p<0,0001), e a proporção de citocinas IFN-γ, TNF-α, IL-12 e IL-17 produzidas pelas célula TDC γδ foi maior do que as produzidas pelas células TDC αβ, mas foram diminuídas sob condições de resposta ao sistema imunológico relacionada ao tumor (p<0,0001). Conclusão Camundongos saudáveis induzidos ao tumor de mama 4T1 apresentaram TDC com repertório TCR γδ. Estas células expressam moléculas citotóxicas de linfócitos T, produzindo citocinas proinflamatórias anti-tumor.

γδ T cells response to Mycobacterium tuberculosis in pulmonary tuberculosis patients using preponderant complementary determinant region 3 sequence.

Background & objectives: The unique immunological functions of γδ T lymphocytes to contribute immunity against Mycobacterium tuberculosis attracted interest of researchers. However, little is known about the specificity of γδ Τ cell in tuberculosis patients and the lack of exact tuberculosis antigen recognized by γδ T cells limited its application. The analysis of complementary determinant region (CDR)3 sequence characteristic in γδ T cells of tuberculosis patients would contribute to understand the distribution specificity of γδ T cell. In present study, we investigated the diversity of the γ9/δ2 T cell immunorepertoire and analysed the specificity of the expressed CDR3 in pulmonary tuberculosis patients. Methods: The total RNA in peripheral blood mononuclear cell of 50 pulmonary tuberculosis patients and 10 healthy controls was extracted. The polymerase chain reaction was used to specifically amplify the CDR3 region of γ9 and δ2 chain. The PCR products were ligated into the pGEM-T easy vector. The plasmid DNA was sequenced using the ABI3700 and the T7 primer. Results: Our findings showed that predominant CDR3 sequence of δ2 chain in pulmonary tuberculosis patients was CACDTLVSTDKLIFGKG. The sequence specifically exists in almost all pulmonary tuberculosis patients. The conserved hydrophobic acid residue in 97 positions is present in the γδ T cell reactive to M. tuberculosis. The length of δ2 CDR3 in pulmonary tuberculosis patients has no relation with the disease progress. Interpretation & conclusions: Our results suggest that γδ T cells appear to use CDR3 sequence to recognise M. tuberculosis antigen. γδ T cells reactive to M. tuberculosis were diverse and polyclonal.