Cytokine kinetics in nasal mucosa and sera: new insights in understanding upper-airway disease of marathon runners.

Recently, many authors have proposed that mechanisms such as inflammation and/or allergies could be partly responsible for cases of upper respiratory tract illnesses that affect athletes after exhaustive exercise. Here we studied the kinetics of cytokines in the serum and nasal mucosa of athletes after a marathon. We were able to demonstrate an increase in serum levels of all interleukins studied immediately after the marathon in athletes that present or not with upper airways symptoms followed by a return to basal levels 72 hours after the race, as described in the literature. Interleukin (IL)-10 behaviour differed in the group of asymptomatic athletes. Measurement of this cytokine in protein extract of nasal mucosal cells showed increase 72 hours after the marathon. Levels of this cytokine in sera were increased at rest in athletes that did not present symptoms. These fin- dings suggest that the maintenance of a non-inflammatory environment in the mucosal airways is an active process that requires participation of the systemic and mucosal immune systems. We propose that the understanding of the upper airway disease of the athlete involves the study of mucosal and systemic immune systems.

The Paracoccidioides brasiliensis gp70 antigen is encoded by a putative member of the flavoproteins monooxygenase family.

Glycoprotein gp70 is an important intracellular antigen from Paracoccidioides brasiliensis that elicits both humoral and cellular immune responses. Herein, the PbGP70 gene cloning from isolate Pb18 using internal peptide sequence information is reported. The deduced protein sequence bears two N-glycosylation sites, antigenic sites and two mouse T-cell epitopes. Anti-recombinant gp70 (rPbgp70) polyclonal antibodies reacted with a 70-kDa component in total cell extract of P. brasiliensis, while MAbC5F11 and paracoccidioidomycosis patients' sera recognized rPbgp70. Confocal microscopy with anti-rPbgp70 and MAbC5F11 showed intense staining and cytoplasmatic co-localization. The protein sequence belongs to the flavoprotein monooxygenase family which groups important anti-oxidative bioactive compounds. We found increased PbGP70 transcript accumulation under oxidative stress induced by H(2)O(2), during fungal growth and in macrophage phagocyted/bound yeasts. Therefore, gp70 might play a dual role in P. brasiliensis by both eliciting immune cellular and humoral responses in the host and protecting the fungus from oxidative stress generated by phagocytic cells.

Co-ordinated expression of lymphoid and myeloid specific transcription factors during B-1b cell differentiation into mononuclear phagocytes in vitro.

We previously demonstrated that B-1b cells can undergo differentiation to acquire a mononuclear phagocyte phenotype upon attachment to substrate in vitro. Here we followed the expression of surface markers and transcription factors during this differentiation. B-1b cells spontaneously express both myeloid and lymphoid restricted transcription factors. When induced to differentiate into a phagocyte, the lymphoid genes E box protein (E2A), early B-cell factor (EBF), paired box 5 (Pax5) are down-modulated, while expression of genes related to myeloid commitment is sustained. Furthermore, B-1b cell-derived phagocytes (B-1CDPs) decrease immunoglobulin M (IgM) expression but retain the expression of the heavy chain variable gene VH11 or VH12, an immunoglobulin gene rearrangement predominantly expressed by B-1 cells. The maintenance of lymphoid characteristics in B-1CDPs characterizes a unique type of phagocyte, not related to monocyte-derived macrophages.

Combined Exercise Training Performed by Elderly Women Reduces Redox Indexes and Proinflammatory Cytokines Related to Atherogenesis.

Cardiovascular benefits for the general population of combined aerobic-resistance exercise training are well-known, but the impact of this exercise training modality on the plasma lipid, inflammatory, and antioxidant status in elderly women that are exposed to a great risk of developing ischemic cardio- and cerebrovascular diseases has not been well investigated. So, we aimed to evaluate the plasma lipids, oxidative stress, and inflammatory cytokines in 27 elderly women (TRAINED group, 69.1 ± 8.1 yrs) that were performing moderate intensity combined aerobic-resistance exercise training (3 times/week for at least 18 months) and in 27 sedentary elderly women (SED group, 72.0 ± 6.4 yrs), not submitted to exercise training for at least 5 yrs. Our results showed that BMI was lower in the TRAINED group than in the SED group (25.1 ± 3.2 vs. 28.7 ± 5.1, p < 0.05). The TRAINED group had lower glycemia (92 ± 3 vs. 118 ± 12, p < 0.05), glycated hemoglobin (5.9 ± 0.1 vs. 6.4 ± 0.2, p < 0.05), and triglycerides (98 (75-122) vs. 139 (109-214), p < 0.01); equal total cholesterol (199 (175-230) vs. 194 (165-220)), LDL-cholesterol (108 (83-133) vs. 109 (98-136)), and non-HDL-cholesterol (54 (30-74) vs. 62 (26-80)); and also higher HDL-cholesterol (64 (52-77) vs. 52 (44-63), p < 0.01) and LDL-C/oxLDL ratio (13378 ± 2570 vs. 11639 ± 3113, p < 0.05) compared to the SED group. Proinflammatory cytokines as IL-1ß (11.31 ± 2.4 vs. 28.01 ± 4.7, p < 0.05), IL-6 (26.25 ± 7.4 vs. 49.41 ± 17.8, p < 0.05), and TNF-α (25.72 ± 2.8 vs. 51.73 ± 4.2, p < 0.05) were lower in the TRAINED group than in the SED group. The TRAINED group had lower total peroxides (26.3 ± 7.4 vs. 49.0 ± 17.8, p < 0.05) and oxidized LDL (1551 ± 50.33 vs. 1773 ± 74, p < 0.02) and higher total antioxidant capacity (26.25 ± 7.4 vs. 49.41 ± 17.8, p < 0.001) compared to the SED group. In conclusion, in TRAINED women, BMI was lower, plasma lipid profile was better, plasma oxidative stress was diminished, and there was less expression of proinflammatory interleukins than in SED, suggesting that combined aerobic-resistance exercise training may promote the protection against the complications of ischemic cardio- and cerebrovascular disease in elderly women.

Autoantibodies directed to extracellular matrix components in patients with different clinical forms of periodontitis.

BACKGROUND: Periodontal disease occurs in different clinical forms, from mild and easily controllable to more aggressive inflammatory manifestations, with difficult clinical or surgical control. There is evidence that a local autoimmune reaction may participate in the onset and persistence of the aggressive forms of periodontal disease. As the underlying mechanism in this process is not fully understood, we decided to investigate whether patients bearing this form of disease presented higher levels of antibodies directed to extracellular matrix (ECM) components such as type I collagen, fibronectin, and laminin. METHODS: Three groups of patients were selected by clinical criteria: 22 subjects with aggressive periodontitis (AgP) = group A; 18 subjects with chronic periodontitis (CP) = group B; and 10 healthy (H) volunteers without periodontal disease = group C. Autoantibody levels were evaluated in the sera of these patients using the enzyme-linked immunosorbent assay (ELISA) method. RESULTS: The levels of autoantibodies directed to ECM components (type I collagen, fibronectin and laminin) in the sera of patients with AgP and CP were shown to be statistically different (P <0.05). CONCLUSIONS: Although the present findings suggest an involvement of autoantibodies directed to ECM components per se in the pathogeny of certain types of periodontal disease, the available data do not support the classification of the lesions as autoimmune. Nevertheless, the findings open a possibility for the development of an additional method for a differential diagnosis of the aggressive forms of periodontal disease.

Binding of laminin to Paracoccidioides brasiliensis induces a less severe pulmonary paracoccidioidomycosis caused by virulent and low-virulence isolates.

The pathogenic fungus Paracoccidioides brasiliensis is the causative agent of paracoccidioidomycosis (PCM). This pulmonary mycosis, acquired by inhalation of airborne propagules, may disseminate to several internal organs and tissues, leading to severe disease. Adhesion to host cell components is the first step involved in dissemination of pathogens. Previous studies showed that laminin, the most abundant glycoprotein of the basement membrane, binds to P. brasiliensis yeast cells, enhancing their pathogenicity in the hamster testicle model. As PCM is primarily a pulmonary infection, we studied the influence of previous treatment of yeast cells with laminin on the course of the intratracheal infection of resistant and susceptible mice using high-virulence (Pb18) and low-virulence (Pb265) P. brasiliensis isolates. Laminin treatment did not alter fungal loads, delayed-type hypersensitivity reactions, levels of pulmonary cytokines and production of specific antibodies in any group of Pb18-infected mice. However, early in the infection, a less intense inflammatory reaction was detected in the lungs of the laminin-treated groups. In addition, laminin treatment of Pb265 resulted in a less severe infection as revealed by the lower fungal loads recovered from lungs. Antibody and cytokine levels, however, did not change after laminin treatment. Altogether, our results demonstrate that laminin binding to yeast cells diminishes P. brasiliensis pathogenicity. The lower inflammatory response observed with the virulent isolate and the decreased pulmonary fungal burden with the low-virulence isolate indicate an inhibitory effect of laminin treatment on P. brasiliensis infectivity and interaction with pulmonary host cells or extracellular matrix proteins.

B-1 cells promote immunosurveillance against murine melanoma in host absence of CCR5: new perspective in autologous vaccination therapy.

Autologous vaccination with tumor-primed dendritic cells increases immune response against tumor, which seems to be improved in host absence of CCR5. Because B-1 lymphocytes modulate the activity of different immune cells, we decided to study their influence in the resistance against murine B16F10 melanoma in a CCR5 deprived environment. Adoptive transfer of peritoneal B-1 CCR5(+/+) lymphocytes to CCR5(-/-) animals inhibited the establishment of lung metastasis and melanoma cell growth, in comparison to saline-treated CCR5(-/-) mice. In loco cell analysis demonstrated that the adoptive transfer of B-1 CCR5(+/+) lymphocytes to CCR5 deficient host was associated with a more intense influx of T CD8(+) to tumor site, indicating that the presence of CCR5(+/+) B-1 cells in the tumor environment induces the migration of T CD8 CCR5(-/-) cells to the implantation site. To corroborate this idea, CCR5(-/-) mice were injected with non B-1 peritoneal cells from wild type (WT) mice before B16F10 inoculation. In this regimen, CCR5(-/-) mice were not protected from tumor growth reinforcing the idea that, in host absence of CCR5, B-1 cells are essential to confer tumor resistance. This work indicates that, in the host absence of CCR5, naive B-1 cells may activate CD8T lymphocytes thereby promoting tumor resistance. Our results strongly suggest that autologous vaccination with B-1 lymphocytes in combination with CCR5 antagonists can be an alternative approach to tumor therapy.

Increased production of autoantibodies and specific antibodies in response to influenza virus vaccination in physically active older individuals.

Immunosenescence is associated to aging and among many changes in immune response is reported a reduced response to vaccination and an increase in the number of cases of autoimmunity, caused by autoantibodies known as natural antibodies whose function, according to reports, would be protection against infection and inflammation. Although immunosenescence is an irreversible process, regular moderate exercise can attenuate some aspects of the decline in the immune system. So, the aim of this study was to investigate the humoral immune response in physically active elderly individuals before and 30 days after vaccination against influenza virus. The results showed that the percentage of individuals positive for antinuclear antibodies and serum immunoglobulin M and G levels after vaccination were higher in the group that exercised regularly than in the sedentary group. We were also able to demonstrate a significant correlation between levels of natural autoantibodies and response to vaccination.

Immune alterations after selective rapid eye movement or total sleep deprivation in healthy male volunteers.

We investigated the impact of two nights of total sleep deprivation (SD) or four nights of rapid eye movement (REM) SD on immunological parameters in healthy men. Thirty-two volunteers were randomly assigned to three protocols (control, total SD or REM SD). Both SD protocols were followed by three nights of sleep recovery. The control and REM SD groups had regular nights of sleep monitored by polysomnography. Circulating white blood cells (WBCs), T- (CD4/CD8) and B-lymphocytes, Ig classes, complement and cytokine levels were assessed daily. Two nights of total SD increased the numbers of leukocytes and neutrophils compared with baseline levels, and these levels returned to baseline after 24 h of sleep recovery. The CD4(+) T-cells increased during the total SD period (one and two nights) and IgA levels decreased during the entire period of REM SD. These levels did not return to baseline after three nights of sleep recovery. Levels of monocytes, eosinophils, basophils and cytokines (IL-1ß, IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ) remained unchanged by both protocols of SD. Our findings suggest that both protocols affected the human immune profile, although in different parameters, and that CD4(+) T-cells and IgA levels were not re-established after sleep recovery.

Dendritic cells transfected with scFv from Mab 7.B12 mimicking original antigen gp43 induces protection against experimental Paracoccidioidomycosis.

Paracoccidioidomycosis (PCM), endemic in Latin America, is a progressive systemic mycosis caused by Paracoccidioides brasiliensis (P. brasiliensis), which primarily attacks lung tissue. Dendritic cells (DCs) are able to initiate a response in naïve T cells, and they also participate in Th-cell education. Furthermore, these cells have been used for therapy in several disease models. Here we transfected DCs with a plasmid (pMAC/PS-scFv) encoding a single chain variable fragment (scFv) of an anti-Id antibody that is capable of mimicking gp43, the main antigenic component of P. brasiliensis. First, Balb/c mice were immunized subcutaneously with pMAC/PS-scFv and, after seven days, scFv protein was presented to the regional lymph nodes cells. Moreover, we showed that the DCs transfected with scFv were capable of efficiently activating proliferation of total lymph node cells and inducing a decrease in lung infection. Therefore, our results suggested that the use of scFv-transfected DCs may be a promising therapy in the paracoccidioidomycosis (PCM) model.

Endothelial nitric oxide synthase uncoupling as a key mediator of melanocyte malignant transformation associated with sustained stress conditions.

Melanoma cell lines and cells corresponding to premalignant melanocytes were established by our group after subjecting a nontumorigenic murine melanocyte lineage, melan-a, to sequential cycles of anchorage blockade. Previous results showed that in melan-a cells the superoxide level increases after such procedure. Superoxide production during melanocyte de-adhesion was inhibited by L-sepiapterin, the precursor of eNOS cofactor BH4, and increased by the inhibitor of BH4 synthesis, DAHP, hence indicating a partial uncoupling state of eNOS. The eNOS uncoupling seems to be maintained in cells derived from melan-a, because they present decreased nitric oxide and increased superoxide levels. The inhibition of superoxide production in Tm5 melanoma cells with L-sepiapterin reinforces their eNOS-uncoupled state. The maintenance of oxidative stress seems to be important in melanoma apoptosis resistance because Mn(III)TBAP, a superoxide scavenger, or L-sepiapterin renders Tm5 cells more sensitive to anoikis and chemotherapy. More importantly, eNOS uncoupling seems to play a pivotal role in melanocyte malignant transformation induced by sustained anchorage impediment, because no malignant transformation was observed when L-NAME-treated melanocytes were subjected to sequential cycles of de-adhesion. Our results show that uncoupled eNOS contributes to superoxide production during melanocyte anchorage impediment, contributing to anoikis resistance and malignant transformation.

Resident peritoneal inflammatory cells are pivotal in the development of experimental atherosclerosis.

AIM: Based on evidence that ionizing radiation can ameliorate chronic and autoimmune diseases in patients and experimental animals, we investigated the effects of radiation on the induction and development of experimental atherogenesis. METHODS: Male New Zealand rabbits were divided into 5 groups and given an atherogenic diet for 90 days. Peritoneal and thoracic areas (9 Gy) were irradiated on the 1st and 45th days for groups 1 and 2, the 45th day for groups 3 and 4, and not at all for group 5. Prior to irradiation, the peritoneal cavity of animals from groups 1 and 3 was washed with buffered saline. Cells collected by peritoneal washing were reinfused into the peritoneal cavity of the same animal after irradiation. Animals from groups 2 and 4 were intraperitoneally injected with saline as a control. RESULTS: Despite similar lipid profiles among the experimental groups, the percentage of aortas covered by plaques was remarkably reduced (p<0.001) among animals submitted to irradiation (groups 2 and 4). These differences were completely abolished in irradiated animals reconstituted with their own peritoneal cells. CONCLUSIONS: These findings point to an important role of resident inflammatory peritoneal cells in experimental atherogenesis.