Using two mouse strains with different abilities to generate interferon (IFN)-c production afterMycobacterium tuberculosis infection, we tested the hypothesis that the frequency and activity of regulatory T (Treg) cells are influenced by genetic background. Our results demonstrated that the suppressive activity of spleen Treg cells from infected or uninfected BALB/c mice was enhanced, inhibiting IFN-c and interleukin (IL)-2 production. Infected C57BL/6 mice exhibited a decrease in the frequency of lung Treg cells and an increased ratio CD4 + :CD4 + Foxp3 + cells compared with infected BALB/c mice and uninfected C57BL/6 mice. Moreover, infected C57BL/6 mice also had a decrease in the immunosuppressive capacity of spleen Treg cells, higher lung IFN-c and IL-17 production, and restricted the infection better than BALB/c mice. Adoptive transfer of BALB/c Treg cells into BALB/c mice induced an increase in bacterial colony-forming unit (CFU) counts. Furthermore, BALB/c mice treated with anti-CD25 antibody exhibited lung CFU counts significantly lower than mice treated with irrelevant antibody. Our results show that in BALB/c mice, the Treg cells have a stronger influence than that in C57BL/6 mice. These data suggest that BALB/c and C57BL/6 mice may use some different mechanisms to control M. tuberculosis infection. Therefore, the role of Treg cells should be explored during the development of immune modulators, both from the perspective of the pathogen and the host.

Our results suggest that lower expression of HLA-DRA, HLA-DPA1, and HLA-DPB1 genes may contribute to more aggressive disease in pediatric ACT. HLA-DPA1 immunostaining may represent potential aggressiveness marker in this tumor.

Deregulation of the IGF system observed in human tumors indicates a role in malignant cell transformation and in tumor cell proliferation. Although overexpression of the IGF2 and IGF1R genes was described in adrenocortical tumors (ACTs), few studies reported their profiles in pediatric ACTs. In this study, the IGF2 and IGF1R expression was evaluated by RT-qPCR according to the patient's clinical/pathological features in 60 pediatric ACT samples, and IGF1R protein was investigated in 45 samples by immunohistochemistry (IHC). Whole transcriptome and functional assays were conducted after IGF1R inhibition with OSI-906 in NCI-H295A cell line. Significant IGF2 overexpression was found in tumor samples when compared with non-neoplastic samples (P < 0.001), significantly higher levels of IGF1R in patients with relapse/metastasis (P = 0.031) and moderate/strong IGF1R immunostaining in 62.2% of ACTs, but no other relationship with patient survival and clinical/pathological features was observed. OSI-906 treatment downregulated genes associated with MAPK activity, induced limited reduction of cell viability and increased the apoptosis rate. After 24 h, the treatment also decreased the expression of genes related to the steroid biosynthetic process, the protein levels of the steroidogenic acute regulatory protein (STAR), and androgen secretion in cell medium, supporting the role of IGF1R in steroidogenesis of adrenocortical carcinoma cells. Our data showed that the IGF1R overexpression could be indicative of aggressive ACTs in children. However, in vitro treatments with high concentrations of OSI-906 (>1 μM) showed limited reduction of cell viability, suggesting that OSI-906 alone could not be a suitable therapy to abolish carcinoma cell growth. 23:6Research R C P Lira et al.IGF1R in pediatric adrenocortical tumor IGF2 and IGF1R in pediatric adrenocortical tumors: roles in metastasis and steroidogenesis

Summary CD4+ Foxp3 + regulatory T cells inhibit the production of interferon-c, whichis the major mediator of protection against Mycobacterium tuberculosis infection. In this study, we evaluated whether the protection conferred by three different vaccines against tuberculosis was associated with the number of spleen and lung regulatory T cells. found in BCG/DNA-hsp 65-immunized or BCG/CFP-CpG-immunized mice, the lungs of both groups of mice were better preserved than those of DNAhsp 65-immunized mice. These results confirm the protective efficacy of BCG/DNA-hsp 65 and BCG/CFP-CpG heterologous prime-boost vaccines and the DNA-hsp 65 homologous vaccine. Additionally, the prime-boost regimens assayed here represent a promising strategy for the development of new vaccines to protect against tuberculosis because they probably induce a proper ratio of CD4 + and regulatory (CD4 + Foxp3 + ) cells during the immunization regimen. In this study, this ratio was associated with a reduced number of regulatory cells and no injury to the lungs.

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