Bovine Lactoferrin Counteracts Toll-Like Receptor Mediated Activation Signals in Antigen Presenting Cells

Lactoferrin (LF), a key element in mammalian immune system, plays pivotal roles in host defence against infection and excessive inflammation. Its protective effects range from direct antimicrobial activities against a large panel of microbes, including bacteria, viruses, fungi and parasites, to antinflammatory and anticancer activities. In this study, we show that monocyte-derived dendritic cells (MD-DCs) generated in the presence of bovine LF (bLF) fail to undergo activation by up-modulating CD83, co-stimulatory and major histocompatibility complex molecules, and cytokine/chemokine secretion. Moreover, these cells are weak activators of T cell proliferation and retain antigen uptake activity. Consistent with an impaired maturation, bLF-MD-DC primed T lymphocytes exhibit a functional unresponsiveness characterized by reduced expression of CD154 and impaired expression of IFN-γ and IL-2. The observed imunosuppressive effects correlate with an increased expression of molecules with negative regulatory functions (i.e. immunoglobulin-like transcript 3 and programmed death ligand 1), indoleamine 2,3-dioxygenase, and suppressor of cytokine signaling-3. Interestingly, bLF-MD-DCs produce IL-6 and exhibit constitutive signal transducer and activator of transcription 3 activation. Conversely, bLF exposure of already differentiated MD-DCs completely fails to induce IL-6, and partially inhibits Toll-like receptor (TLR) agonist-induced activation. Cell-specific differences in bLF internalization likely account for the distinct response elicited by bLF in monocytes versus immature DCs, providing a mechanistic base for its multiple effects. These results indicate that bLF exerts a potent anti-inflammatory activity by skewing monocyte differentiation into DCs with impaired capacity to undergo activation and to promote Th1 responses. Overall, these bLF-mediated effects may represent a strategy to block excessive DC activation upon TLR-induced inflammation, adding further evidence for a critical role of bLF in directing host immune function

Design and Analysis of Rhesus Cytomegalovirus IL-10 Mutants as a Model for Novel Vaccines against Human Cytomegalovirus

Human cytomegalovirus (HCMV) expresses a viral ortholog (CMVIL-10) of human cellular interleukin-10 (cIL-10). Despite only ∼26% amino acid sequence identity, CMVIL-10 exhibits comparable immunosuppressive activity with cIL-10, attenuates HCMV antiviral immune responses, and contributes to lifelong persistence within infected hosts. The low sequence identity between CMVIL-10 and cIL-10 suggests vaccination with CMVIL-10 may generate antibodies that specifically neutralize CMVIL-10 biological activity, but not the cellular cytokine, cIL-10. However, immunization with functional CMVIL-10 might be detrimental to the host because of its immunosuppressive properties.Structural biology was used to engineer biologically inactive mutants of CMVIL-10 that would, upon vaccination, elicit a potent immune response to the wild-type viral cytokine. To test the designed proteins, the mutations were incorporated into the rhesus cytomegalovirus (RhCMV) ortholog of CMVIL-10 (RhCMVIL-10) and used to vaccinate RhCMV-infected rhesus macaques. Immunization with the inactive RhCMVIL-10 mutants stimulated antibodies against wild-type RhCMVIL-10 that neutralized its biological activity, but did not cross-react with rhesus cellular IL-10.This study demonstrates an immunization strategy to neutralize RhCMVIL-10 biological activity using non-functional RhCMVIL-10 antigens. The results provide the methodology for targeting CMVIL-10 in vaccine, and therapeutic strategies, to nullify HCMV's ability to (1) skew innate and adaptive immunity, (2) disseminate from the site of primary mucosal infection, and (3) establish a lifelong persistent infection

Host Immune Responses to a Viral Immune Modulating Protein: Immunogenicity of Viral Interleukin-10 in Rhesus Cytomegalovirus-Infected Rhesus Macaques

, consistent with a central role for rhcmvIL-10 during acute virus-host interactions. Since cmvIL-10 and rhcmvIL-10 are extremely divergent from the cIL-10 of their respective hosts, vaccine-mediated neutralization of their function could inhibit establishment of viral persistence without inhibition of cIL-10.As a prelude to evaluating cmvIL-10-based vaccines in humans, the rhesus macaque model of HCMV was used to interrogate peripheral and mucosal immune responses to rhcmvIL-10 in RhCMV-infected animals. ELISA were used to detect rhcmvIL-10-binding antibodies in plasma and saliva, and an IL-12-based bioassay was used to quantify plasma antibodies that neutralized rhcmvIL-10 function. rhcmvIL-10 is highly immunogenic during RhCMV infection, stimulating high avidity rhcmvIL-10-binding antibodies in the plasma of all infected animals. Most infected animals also exhibited plasma antibodies that partially neutralized rhcmvIL-10 function but did not cross-neutralize the function of rhesus cIL-10. Notably, minimally detectable rhcmvIL-10-binding antibodies were detected in saliva.This study demonstrates that rhcmvIL-10, as a surrogate for cmvIL-10, is a viable vaccine candidate because (1) it is highly immunogenic during natural RhCMV infection, and (2) neutralizing antibodies to rhcmvIL-10 do not cross-react with rhesus cIL-10. Exceedingly low rhcmvIL-10 antibodies in saliva further suggest that the oral mucosa, which is critical in RhCMV natural history, is associated with suboptimal anti-rhcmvIL-10 antibody responses

Estudo radiológico do valor angular da cifose torácica em adolescentes Estudio radiológico del valor angular de la cifosis torácica en adolescentes Radiological study of the angular value of thoracic kyphosis in adolescents

OBJETIVO: determinar a diferença dos valores angulares da cifose torácica utilizando como vértebra terminal cranial diferentes níveis (T2 a T5). MÉTODOS: foram avaliadas radiografias em perfil de cem adolescentes voluntários saudáveis da Escola Industrial do Serviço Social da Indústria (SESI) de Ribeirão Preto (SP), com prévia autorização dos pais ou responsáveis. Foram excluídas as radiografias de dez indivíduos por falhas na qualidade. Os parâmetros avaliados foram: mensuração da cifose torácica pelo método de Cobb, utilizando T2, T3, T4 ou T5 como vértebra terminal cranial e T12 como vértebra terminal caudal. RESULTADOS: foram avaliados 90 indivíduos (46 do sexo masculino e 44 do feminino), com idade variando de 13 a 15 anos (média 14±6). O valor angular da cifose torácica nos diferentes níveis variou entre 45º (T2-T12) e 35º (T5-T12) no sexo masculino, e valor angular entre 43º(T2-T12) e 30º (T5-T12) no sexo feminino. CONCLUSÃO: foi observada diferença constante de aproximadamente 5º quando comparados os valores angulares da cifose torácica utilizando diferentes níveis (T2 a T5) como vértebra terminal cranial.<br>OBJETIVO: determinar la diferencia de los valores angulares de la cifosis torácica usando como vértebra terminal craneal, diferentes niveles (T2 a T5). MÉTODOS: fueron evaluadas radiografías en perfil de cien adolescentes voluntarios saludables de la Escola Industrial do Serviço Social da Indústria (SESI) de Ribeirão Preto (SP), con previa autorización de sus padres o responsables. Fueron excluidas radiografías de diez individuos por fallas de resolución. Los parámetros evaluados fueron: la medida de la cifosis torácica por el método de Cobb, usando T2,T3,T4 y T5 como vértebra terminal craneal y T12 como vértebra terminal caudal. RESULTADOS: fueron evaluados 90 individuos (46 hombres y 44 mujeres), con edades que varían de 13 a 15 años (media 14±6). El valor angular de la cifosis torácica en los diferentes niveles fue de 45º (T2-T12) y 35º (T5-T12) en el sexo masculino, y valor angular de 43º (T2-T12) y 30º (T5-T12) en el sexo femenino. CONCLUSIÓN: fue observada una diferencia constante de aproximadamente 5º cuando los valores angulares de la cifosis torácica fueron comparados, usando diferentes niveles (T2 a T5) como vértebra terminal craneal.<br>OBJECTIVE: to determine the difference of the thoracic kyphosis angular values using different levels (T2 a T5) as a terminal cranial vertebra. METHODS: sagittal radiographies of one hundred healthy adolescent volunteers, who study at Escola Industrial do Serviço Social da Indústria (SESI) in Ribeirão Preto SP), were evaluated the sagittal radiographies of one hundred health volunteers adolescent, that studies at Escola Industrial do SESI in Ribeirão Preto (SP), with parents consent. Ten adolescents were excluded because of flaws in the quality. The studied parameters were: the measurement of thoracic kyphosis by the Cobb method, using T2, T3, T4, T5 as a terminal proximal vertebra and T12 as a distal final vertebra. RESULTS: Ninety individuals (46 men and 44 women), aged from 13 to 15 (average of 14±6), were evaluated. The angular value of thoracic kyphosis in the different levels varied from 46º (T2 - T12) to 35º (T5 - T12) in men, and from 44º (T2- T12) to 30º (T5 - T12) in women. CONCLUSION: A constant difference of approximately 5º was observed when comparing the angular values of thoracic kyphosis using different levels (T2 - T5) as a terminal cranial vertebra