Fcγ receptors on aging neutrophils

Abstract Objective Neutrophils are key effector cells of the innate immune system. They recognize antigens through membrane receptors, which are expressed during their maturation and activation. Neutrophils express FcγRII (CD32), FcγRIII (CD16), and FcγRI (CD64) after being activated by different factors such as cytokines and bacterial products. These receptors are involved with phagocytosis of IgG-opsonized microbes and enhance defense mechanisms. Based on that, our study seeks to compare the expression of FcγRII, FcγRIII, FcγRI, and CD11b on neutrophils from elderly and young subjects and their expression after in vitro activation with cytokines and LPS. Methodology Neutrophils were isolated from human peripheral blood and from mice bone marrow by density gradient. After isolation, FCγRs expression was immediately analyzed by flow cytometry or after in vitro stimulation. Results In freshly isolated cells, the percentage of FcγRIIIb+ and CD11b+ neutrophils were higher in samples from young individuals; FcγRIIIa expression was more prominent on aged neutrophils; FcγRIA expression was similar in all samples analyzed. Exposure to CXCL8 and LPS resulted in a higher percentage of FcγRIa+ neutrophils on elderly individuals' samples but lower when compared with neutrophils from young donors. We observed that LPS caused an increase in FcγRIIa expression on aging human neutrophils. In contrast, FcγRIIIb expression in response to CXCL8 and LPS stimulation was not altered in the four groups. CD11b expression was lower in neutrophils from elderly individuals even in response to LPS and CXCL8. In mice, we observed differences only regarding CD11b expression, which was increased on aged neutrophils. LPS exposure caused an increase in all FcγRs. Conclusions Our results suggest that, in humans, the overall pattern of FcγR expression and integrin CD11b are altered during aging and immunosenescence might contribute to age-related infection.

Male individuals with Robin Sequence: emerging significant association with ABO and RhD blood group phenotypes

ABSTRACT Background: This study investigated the association of Robin Sequence with ABO and RhD blood group phenotypes. Methods: A retrospective cross-sectional study was performed of a cohort of Robin Sequence patients of the Hospital de Reabilitação de Anomalias Craniofaciais - Universidade de São Paulo (USP), Brazil. The study group was composed of 339 individuals of both genders with Robin Sequence referred for specific treatment. A control group was composed of 1780 individuals without syndromes. The groups were compared using the Pearson' chi-square test (χ 2) with statistical significance being defined for an alpha error of 5% (p-value < 0.05). Results: A comparison of gender found a significant difference for the AB phenotype between groups (p-value = 0.007). Comparing blood type by gender there was no significant difference within the same group (p-value = 0.117 and 0.388 respectively, for Robin Sequence and the control group). When comparing the AB blood type between groups, there was no difference for females (p-value = 0.577), but there was a significant difference for males (p-value = 0.0029). Conclusions: This study showed that the population with Robin Sequence had different patterns related to gender concerning the phenotypic distribution of ABO and RhD blood group phenotypes. Robin Sequence is more common among females. The AB phenotype was significantly higher in males with Robin Sequence than in males of the Control Group. The prevalence of the RhD-negative phenotype is higher in individuals with Robin Sequence. This result suggests a possible association of ABO and RhD phenotypes with Robin Sequence that should be better investigated by molecular studies, as it deserves greater attention.

Sequência de Robin e suas repercussões sobre a microbiota bucal: revisão de literatura / Robin sequence and its repercussions on the oral microbiota: literature review

A cavidade bucal é a principal porta de entrada dos micro-organismos existentes no meio externo para o interior do corpo humano. A sequência de Robin é descrita como uma tríade de anomalias, caracterizada por micrognatia (hipodesenvolvimento mandibular) e glossoptose (deslocamento posterior da língua, que causa obstrução na faringe), com ou sem fissura palatina associada. Diante disso, o objetivo do presente estudo foi realizar uma revisão de literatura enfatizando as características principais e peculiares da microbiota bucal de crianças com sequência de Robin. A dificuldade respiratória, de ingestão de nutrientes, aleitamento materno insuficiente, otites recorrentes, entre outras complicações, ocorrem com frequência em crianças com essa patologia, influenciando a composição da microbiota bucal. A associação da palatoplastia e o uso de antibiótico intensificam as mudanças nessa microbiota. Novas investigações devem ser realizadas, para verificar quais fatores relacionados com a malformação craniofacial, ao tratamento cirúrgico e ao uso de antimicrobianos estariam implicados na alteração da microbiota bucal descrita neste trabalho, bem como suas repercussões clínicas...

Evaluation of fecal microorganisms of children with cleft palate before and after palatoplasty

This study isolated and quantified intestinal bacteria of children with cleft palate before and after palatoplasty. A prospective study was conducted from May 2007 to September 2008 on 18 children with cleft palate, aged one to four years, of both genders, attending a tertiary cleft center in Brazil for palatoplasty, to analyze the effect of surgical palate repair on the concentration of anaerobes Bacteroides sp, Bifidobacterium sp and microaerophiles Lactobacillus sp in feces of infants with cleft palate before and 24 hours after treatment with cefazolin for palatoplasty. There was significant reduction of Lactobacillus sp (p < 0.002), Bacteroides sp (p < 0.001) and Bifidobacterium sp (p = 0.021) after palatoplasty, revealing that surgery and utilization of cefazolin significantly influenced the fecal microbiota comparing collections before and after surgery. However, due to study limitations, it was not possible to conclude that other isolated factors, such as surgical stress, anesthetics and other medications used in palatoplasty might have a significant influence on the microbiota. Considering the important participation of the intestinal microbiota on both local and systemic metabolic and immunological activities of the host, professionals should be attentive to the possible influence of these changes in patients submitted to cleft repair.