Hydroquinone exposure alters the morphology of lymphoid organs in vaccinated C57Bl/6 mice.

The influenza is a common viral infection that can be fatal, especially in high-risk groups such as children, pregnant women, elderly, and immune-deficient individuals. Vaccination is the most efficient approach to prevent the spreading of viral infection and promote individual and public health. In contrast, exposure to environmental pollutants such as cigarette smoke reduces the efficacy of vaccination. We investigated whether chronic exposure to hydroquinone (HQ), the most abundant compound of the tobacco particulate phase, could impair the adaptive immune responses elicited by influenza vaccination. For this, adult male C57BL/6 mice were daily exposed to either nebulized HQ or PBS for 1 h for a total of eight weeks. At weeks 6 and 8, the mice were primed and boosted with the trivalent influenza vaccine via IM respectively. Although the HQ exposure did not alter the body weight of the mice and the biochemical and hematological parameters, the pollutant increased the oxidative stress in splenocytes of immunized animals, modified the morphology of spleen follicles, and augmented the size of their lymph nodes. The lymphoid organs of HQ-exposed mice presented a similar number of vaccine-specific IgG-secreting cells, titers of vaccine-specific total IgG, and respective subclasses. Transcriptome studies with HQ, benzene, or cigarette smoke exposure were also analyzed. The genes up-regulated upon pollutant exposure were associated with neutrophil migration and were shown to be co-expressed with antibody-secreting cell genes. Therefore, these findings suggest that HQ exposure may trigger an immune-compensatory mechanism that enhances the humoral responses induced by influenza vaccination.

Hydroquinone exposure alters the morphology of lymphoid organs in vaccinated C57Bl/6 mice

The influenza is a common viral infection that can be fatal, especially in high-risk groups such as children, pregnant women, elderly, and immune-deficient individuals. Vaccination is the most efficient approach to prevent the spreading of viral infection and promote individual and public health. In contrast, exposure to environmental pollutants such as cigarette smoke reduces the efficacy of vaccination. We investigated whether chronic exposure to hydroquinone (HQ), the most abundant compound of the tobacco particulate phase, could impair the adaptive immune responses elicited by influenza vaccination. For this, adult male C57BL/6 mice were daily exposed to either nebulized HQ or PBS for 1 h for a total of eight weeks. At weeks 6 and 8, the mice were primed and boosted with the trivalent influenza vaccine via IM respectively. Although the HQ exposure did not alter the body weight of the mice and the biochemical and hematological parameters, the pollutant increased the oxidative stress in splenocytes of immunized animals, modified the morphology of spleen follicles, and augmented the size of their lymph nodes. The lymphoid organs of HQ-exposed mice presented a similar number of vaccine-specific IgG-secreting cells, titers of vaccine-specific total IgG, and respective subclasses. Transcriptome studies with HQ, benzene, or cigarette smoke exposure were also analyzed. The genes up-regulated upon pollutant exposure were associated with neutrophil migration and were shown to be co-expressed with antibody-secreting cell genes. Therefore, these findings suggest that HQ exposure may trigger an immune-compensatory mechanism that enhances the humoral responses induced by influenza vaccination.

Hydroquinone exposure alters the morphology of lymphoid organs in vaccinated C57Bl/6 mice

The influenza is a common viral infection that can be fatal, especially in high-risk groups such as children, pregnant women, elderly, and immune-deficient individuals. Vaccination is the most efficient approach to prevent the spreading of viral infection and promote individual and public health. In contrast, exposure to environmental pollutants such as cigarette smoke reduces the efficacy of vaccination. We investigated whether chronic exposure to hydroquinone (HQ), the most abundant compound of the tobacco particulate phase, could impair the adaptive immune responses elicited by influenza vaccination. For this, adult male C57BL/6 mice were daily exposed to either nebulized HQ or PBS for 1 h for a total of eight weeks. At weeks 6 and 8, the mice were primed and boosted with the trivalent influenza vaccine via IM respectively. Although the HQ exposure did not alter the body weight of the mice and the biochemical and hematological parameters, the pollutant increased the oxidative stress in splenocytes of immunized animals, modified the morphology of spleen follicles, and augmented the size of their lymph nodes. The lymphoid organs of HQ-exposed mice presented a similar number of vaccine-specific IgG-secreting cells, titers of vaccine-specific total IgG, and respective subclasses. Transcriptome studies with HQ, benzene, or cigarette smoke exposure were also analyzed. The genes up-regulated upon pollutant exposure were associated with neutrophil migration and were shown to be co-expressed with antibody-secreting cell genes. Therefore, these findings suggest that HQ exposure may trigger an immune-compensatory mechanism that enhances the humoral responses induced by influenza vaccination.

Influência da Hidroquinona nas respostas imune humoral e celular induzida por vacina viral com proteína recombinante (Dengue) / The Influence of Hydroquinone in the humoral and cellular immune responses elicited by vaccination with Dengue envelope recombinant Protein

A fumaça do cigarro apresenta mais de 8700 substâncias identificadas, as quais já foram relacionadas com o desenvolvimento das mais variadas doenças. Dentre elas, uma substância relevante neste contexto de toxicidade do cigarro é a hidroquinona (HQ), gerada após a biotransformação do benzeno inalado. A HQ apresenta atividades relacionadas com a imunossupressão das respostas imune inata e adaptativa, observados mais no contexto in vitro e parcamente no in vivo; contudo, nenhum estudo ainda trouxe a abordagem do efeito da exposição à HQ sobre a resposta induzida por vacinação. Sendo assim, será que a exposição à fumaça do cigarro ou à HQ influenciaria na resposta de células B e geração de anticorpos induzidas por imunizações com vacinas anti-virais? Observamos que, após a exposição diária com 2500 ppm de HQ (equivalente a um maço de cigarro fumado / dia) por 8 semanas e vacinação com proteína recombinante codificadora do domínio III do Envelope do vírus da Dengue sorotipo 2 (EDIII) mais o adjuvante Alum, houve uma "tendência" para menores títulos de IgG total e IgG1 específicos à EDIII em camundongos C57BL/6. Análises histológicas revelaram um menor número de folículos e redução significativa de suas áreas no baço do grupo HQ em comparação com os não expostos. Para entendermos o efeito da HQ sobre a resposta humoral, realizamos uma análise de dados públicos de transcriptoma obtidas de amostras de sangue de humanos. Curiosamente, observamos que a HQ regula positivamente genes relacionados com a ativação de células B, assim como a migração e quimiotaxia de neutrófilos e outros leucócitos. Como é sabido que existe uma população de neutrófilos (N2) com a capacidade de auxiliar as respostas de células B, hipotetizamos que essas células poderiam disparar um mecanismo imunocompensatório que aumenta os títulos de anticorpos no grupo HQ

The cigarette smoke has more than 8700 harmful substances related to the occurrence of the most varied diseases. Among them, a relevant substance is the hydroquinone (HQ), generated upon the biotransformation of inhaled benzene. In vitro and in vivo analyses have demonstrated that HQ can suppress both innate and adaptive immune responses. However, no study has approached the effect of the HQ exposure on the vaccination-induced response. Thus, would the exposure to the cigarette smoke or HQ influence the B-cell and antibody responses elicited by immunizations with antiviral vaccines? We observed a "tendency" to lower titers of IgG total and IgG1 anti-EDIII in mice daily exposed to 2,500 ppm of HQ for 8 weeks and vaccinated. Histological analyses revealed a smaller number of follicles and a significant reduction in their area in the HQ group in comparison to their counterparts. In order to understand the effect of the HQ on the humoral response, we performed an analysis of public transcriptome data derived from human blood samples. We observed that the HQ up-regulates the expression of genes related to B cell activation as well as the migration and chemotaxis of neutrophils and other leukocytes. Considering that N2 neutrophils have the ability to help the B cell response, we have hypothesized that the HQ exposure may trigger an immunocompensatory effect, increasing the humoral response