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Preeclampsia (PE) is a human pregnancy-specific syndrome with abnormal activation of cells from the innate immune system. The present study evaluated whether silibinin (SB) treatment of monocytes from preeclamptic women could modulate NLRP1 and NLRP3 inflammasomes as well as TLR4/NF-κB pathway activation. Peripheral blood monocytes from 20 preeclamptic and 20 normotensive (NT) pregnant women, as well as the THP-1 cell line, were cultured with or without monosodium urate (MSU) or SB. NLRP1, NLRP3, Caspase-1, TLR4, MyD88, NF-κB, IL-1β, IL-18, TNF-α and IL-10 gene expression by monocytes was analysed by quantitative real-time polymerase chain reaction (qPCR), while inflammatory cytokine production and p65NF-κB activity were determined by enzyme-linked immunosorbent assays (ELISAs). TLR4/MyD88/NF-κB and NLRP1/NLRP3 inflammasomes pathways in THP-1 cells were evaluated by flow cytometry and western blot respectively. Compared with NT women, monocytes from preeclamptic women showed The Ethics Committee of the Botucatu Medical School approved the study (protocol number 2.333.216)higher endogenous activation of NLRP1/NLRP3 inflammasomes and the TLR4/NF-κB pathway as well as higher gene and protein expression of IL-1β, IL-18 and TNF-α, and lower expression of IL-10. Monocyte stimulation with MSU increased inflammation-related genes as well as NF-κB activity. In vitro, SB treatment of monocytes from preeclamptic women reduced the basal activation of these cells by decreasing NLRP1/NLRP3 inflammasomes and p65NF-κB activity. THP-1 cells exhibited a similar immunological response profile to monocytes from preeclamptic women when cultured with or without MSU or SB. These results suggest uric acid participates in the systemic inflammatory response characteristic of preeclampsia and that in vitro SB treatment can modulate the sterile inflammation established in monocytes from preeclamptic women.

Dendritic cells (DCs) have been attracting attention in cancer immunotherapy because of their role in inducing and modulating effective immune responses. Besides the direct contact with other cell types and the secretion of cytokines, it is becoming clear that nanovesicles, such as exosomes (Exo), secreted by DCs also have a role in their function. Conversely, tumor-derived Exo carry antigens and have been used as a source of specific stimulus for the immune response against tumors. At the same time, several works have shown that different cells types incorporate DC-derived Exo (DC-Exo), resulting in modifications of their phenotype and function. Since DC-Exo carry many of the immune function-associated molecules of DCs, their incorporation by tumor cells could turn tumor cells into immunogenic targets. We have, therefore, treated human breast adenocarcinoma cells (SK-BR-3) with DCs-Exo and used these to stimulate previously SK-BR-3-primed CD3(+) T-cells. Sensitized T-cells cultured with DC-Exo-treated tumor cells showed a significantly higher percentage of IFN-γ-secreting cells (as measured by ELISPOT), when compared to the frequency of cells responding to non-DC-Exo-treated cells. These data show that the incorporation of DC-Exo by the tumor cells increased their ability to activate T-cells for a possibly more effective response, thus showing that DC-Exo may become another tool in cancer immunotherapy.

Obesity in adolescents has reached epidemic proportions and is associated with the inflammatory response and viral infections. The aim of this study was to understand the profile of inflammatory cytokines and chemokines associated with the inflammatory response and metabolic syndrome (MetS) in obese adolescents with positive serology for adenovirus 36 (ADV36). Thirty-six overweight, 36 obese, and 25 severe obesity adolescents aged 10 to 16 years were included in the study. The following variables were analyzed: sex, age, body mass index (BMI), blood pressure, total cholesterol and fractions, triglycerides, glucose, serum cytokine concentrations, and ADV36 antibodies. Cytokines and chemokines were quantified by cytometry and ADV36 serology was determined by enzyme-linked immunosorbent assay (ELISA). The results showed higher levels of the cytokines interleukin-1beta (IL-1β), IL-6, IL-10 and of the chemokine interferon-gamma-inducible protein 10 (IP-10) in severe obesity adolescents compared to the obese and overweight groups, as well as in the group with MetS compared to the group without this syndrome. The frequency of ADV36-positive individuals did not differ between groups. The findings revealed differences in BMI between the obese and severe obesity groups versus the overweight group in the presence of positivity for ADV36, suggesting an association with weight gain and possibly MetS installation.

Paracoccidioidomycosis (PCM), a systemic mycosis endemic in Latin America, occurs after inhalation of mycelial components of Paracoccidioides spp. When the fungus reaches the lungs and interacts with the alveolar macrophages and other cells, phagocytic cells such as neutrophils and monocytes are immediately recruited to the injured site. The interaction between surface molecules of pathogens and homologous receptors, present on the surface membrane of phagocytes, modulates the innate immune cell activation. Studies have shown the importance of fungal recognition by the Dectin-1 receptor, which can induce a series of cellular protective responses against fungi. The objective of the present study was to evaluate Dectin-1 receptor expression and the effector mechanisms of human monocytes and neutrophils activated or not with different cytokines, such as IFN-γ, TNF-α, and GM-CSF, followed by the challenge with Paracoccidioides brasiliensis (P. brasiliensis or Pb265). Therefore, analysis of Dectin-1 receptor expression was done by flow cytometry whereas the effector mechanisms were evaluated by fungal recovery by colony-forming unit (CFU) counting and hydrogen peroxide (H2O2) production. Our results showed that, after treatment with IFN-γ, TNF-α, and GM-CSF and challenge with Pb265, cells, especially monocytes, demonstrated an increase in Dectin-1 expression. Both types of cells treated with the cytokines exhibited a decreased fungal recovery and, conversely, an increased production of H2O2. However, when cultures were treated with an anti-Dectin-1 monoclonal antibody, to block the P. brasiliensis binding, a decrease in H2O2 production and an increase in fungal recovery were detected. This effect was observed in all cultures treated with the specific monoclonal antibody. These results show the involvement of the Dectin-1 receptor in fungal recognition and its consequent participation in the induction of the killing mechanisms against P. brasiliensis.

AIRmax and AIRmin mice strains were selected according to the intensity of their acute inflammatory responsiveness. Previous studies have shown that AIR mice differ in their resistance to chemically induced skin tumors and in the development of melanoma metastases, in addition to differences in neutrophil and NK cells activity. In the present work, we aimed to evaluate whether the difference of susceptibility to murine melanoma is associated with NK cytotoxic activity against Yac.1 cells and lymphocyte subsets. Mice were subcutaneously inoculated with B16F10 or S91 melanoma cells. After 7, 14, or 30 days, the animals were euthanized to analyze the number of lymphocyte subsets, cytotoxic activity, and number of cytokine-producing spleen cells. AIRmax mice presented a higher number of CD4+/CD25+ cells than that of AIRmin mice following inoculation of B16F10 cells, whereas inoculation of S91 cells reduced CD4+/CD25+ and increased TCD8+ cell subsets in the AIRmax mice. AIRmax mice had a higher number of interleukin (IL)-10- and IL-12-producing cells and a lower number of interferon-γ–producing cells than those of AIRmin mice at 30 days. The cytotoxic activity of nonadherent spleen cells was similar in both the AIR strains. These results suggest that melanoma cells can induce different responses in AIR mice, possibly owing to alterations in regulatory mechanisms, such as the action of CD4+/CD25+ regulatory T cells and IL-10, in AIRmax mice.

The glycoprotein gp43 is the major antigenic/diagnostic component of Paracoccidioides brasiliensis, one of the etiologic agents of paracoccidioidomycosis (PCM). Gp43 has protective roles in mice, but due to adhesive properties, this glycoprotein has also been associated with immune evasion mechanisms. The present study evaluated gp43 interaction in vitro with Toll-like receptors 2 and 4 (TLR2 and TLR4) present in polymorphonuclear neutrophils (PMNs) from healthy human individuals and the consequent modulation of the immune response through the expression and release of cytokines and eicosanoids. PMNs were incubated in the absence or presence of monoclonal antibodies anti-TLR2 and anti-TLR4 (individually or in combination) before gp43 stimulation. Then, PMNs were analyzed for the expression of both surface receptors and the detection of intracytoplasmic IL-17A and IL-4 using flow cytometry, while the production of PGE2, LTB4, IL-6, IL-10, IL-12, IFN-γ, and TNF-α was evaluated in the supernatants by enzyme-linked immunosorbent assay (ELISA). Our results showed that gp43 increased TLR2 and TLR4 expression by PMNs and induced PGE2 and IL-17A via TLR4 and TLR2, respectively. Thus, our data suggest that gp43 from P. brasiliensis might modulate host susceptibility to the fungal infection by affecting PGE2 and IL-17A production.

The relationships between arbuscular mycorrhizal fungi and root morphological characteristics were studied under greenhouse conditions of 78 tropical native woody species and 47 seedling species collected in the field. Seedlings of native woody pioneer and early secondary species that generally exhibited fine roots with a dense cover of long root hairs showed higher mycorrhizal response and root mycorrhizal colonization than late-secondary and climax species with coarse roots with a sparse cover of short root hairs. Root-hair length and incidence decreased with the progression among the successional groups while fine-root diameter increased, both in the greenhouse and in the field. The mycorrhizal response was highly correlated to root mycorrhizal colonization in the greenhouse and in the field. These parameters were inversely correlated with the seed mass and fine-root diameter, but directly correlated with root-hair incidence, both in the greenhouse and in the field. Mycorrhizal response and root mycorrhizal colonization were also directly correlated with the root-hair length and root/shoot ratio of uninoculated plants. The seedling mycorrhizal status of the early successional woody species suggests that the root traits of these fast-growing species can be more receptive to attraction, infection and colonization by arbuscular mycorrhizas than root traits of late-successional species.

Exosomes (Exos) are secreted nanovesicles that contain membrane proteins and genetic material, which can be transferred between cells and contribute to their communication in the body. We show that Exos, obtained from mature human dendritic cells (DCs), are incorporated by tumour cells, which after Exos treatment, acquire the expression of HLA-class I, HLA-class II, CD86, CD11c, CD54 and CD18. This incorporation reaches its peak eight hours after treatment, can be observed in different cell tumour lines (SK-BR-3, U87 and K562) and could be a means to transform non-immunogenic into immunogenic tumour cells. Interestingly, tetraspanins, which are expressed by the tumour cells, have their surface level decreased after Exo treatment. Furthermore, the intensity of Exo incorporation by the different tumour cell lines was proportional to their CD9 expression levels and pre-treatment of Exos with anti-CD9 decreased their incorporation (by SK-BR-3 cells). This modification of tumour cells by DC-derived Exos may allow their use in new immunotherapeutic approaches to cancer. Furthermore, by showing the involvement of CD9 in this incorporation, we provide a possible selection criterion for tumours to be addressed by this strategy.

Immunotherapies have emerged as promising complementary treatments for ovarian cancer (OC), but its effective and direct role on OC cells is unclear. This study examined the combinatory effects of the protein aggregate magnesium–ammonium phospholinoleate–palmitoleate anhydride, known as P-MAPA, and the human recombinant interleukin-12 (hrIL-12) on cell migration/invasion, apoptosis, toll-like receptor (TLR)-mediated inflammation, and cytokine/chemokine profile in human OC cell line SKOV-3. P-MAPA and IL-12 showed cancer cell toxicity under low doses after 48 h. Although apoptosis/necrosis and the cell cycle were unchanged by the treatments, P-MAPA enhanced the sensitivity to paclitaxel (PTX) and P-MAPA associated with IL-12 significantly reduced the migratory potential and invasion capacity of SKOV-3 cells. P-MAPA therapy reduced TLR2 immunostaining and the myeloid differentiation factor 88 (MyD88), but not the TLR4 levels. Moreover, the combination of P-MAPA with IL-12 attenuated the levels of MyD88, interferon regulatory factor 3 (IRF3) and nuclear factor kappa B (NF-kB p65). The IL-12 levels were increased and P-MAPA stimulated the secretion of cytokines IL-3, IL-9, IL-10, and chemokines MDC/CCL22 and, regulated on activation, normal T cells expressed and secreted (RANTES)/CCL5. Conversely, combination therapy reduced the levels of IL-3, IL-9, IL-10, MDC/CCL22, and RANTES/CCL5. Collectively, P-MAPA and IL-12 reduce cell dynamics and effectively target the TLR-related downstream molecules, eliciting a protective effect against chemoresistance. P-MAPA also stimulates the secretion of anti-inflammatory molecules, possibly having an immune response in the OC microenvironment.

Exosomes (Exos) are secreted nanovesicles that contain membrane proteins and genetic material, which can be transferred between cells and contribute to their communication in the body. We show that Exos, obtained from mature human dendritic cells (DCs), are incorporated by tumour cells, which after Exos treatment, acquire the expression of HLA-class I, HLA-class II, CD86, CD11c, CD54 and CD18. This incorporation reaches its peak eight hours after treatment, can be observed in different cell tumour lines (SK-BR-3, U87 and K562) and could be a means to transform non-immunogenic into immunogenic tumour cells. Interestingly, tetraspanins, which are expressed by the tumour cells, have their surface level decreased after Exo treatment. Furthermore, the intensity of Exo incorporation by the different tumour cell lines was proportional to their CD9 expression levels and pretreatment of Exos with anti-CD9 decreased their incorporation (by SK-BR-3 cells). This modification of tumour cells by DC-derived Exos may allow their use in new immunotherapeutic approaches to cancer. Furthermore, by showing the involvement of CD9 in this incorporation, we provide a possible selection criterion for tumours to be addressed by this strategy.