Evaluation of aflibercept and ziv-aflibercept binding affinity to vascular endothelial growth factor, stability and sterility after compounding.

PURPOSE: To investigate the binding affinity, stability, and sterility of aflibercept and ziv-aflibercept to vascular endothelial growth factor (Holash et al. in Proc Natl Acad Sci USA 99(17):11393-11398, 2002. 10.1073/pnas.172398299) after compounding and storage for up to 28 days at 4 °C and - 8 °C. METHODS: Tuberculin-type 1-mL syringes were prepared containing aflibercept (40 mg/mL) and ziv-aflibercept (25 mg/mL). Samples were stored at 4 °C and - 8 °C for 0, 14, and 28 days and evaluated for the binding affinity of anti-VEGF to VEGF and stability using enzyme-linked immunosorbent assays. The evaluation of sample sterility was performed. RESULTS: Laboratory trials with aflibercept and ziv-aflibercept showed preservation of the drug-binding capability to recombinant VEGF when stored in plastic syringes for up to 28 days at 4 °C and - 8 °C. No significant decrease in mass or concentration were observed. Microbiologic evaluations did not detect contamination in the syringes. CONCLUSIONS: The current study corroborates that compounded anti-VEGF drugs aflibercept and ziv-aflibercept do not loose stability or binding affinity and do not become contaminated if prepared under sterile conditions and stored at 4 °C or - 8 °C for 14 or 28 days.

Subpopulações de linfócitos b na fase aguda do infarto do miocárdio estão relacionadas com a massa infartada quantificada por RNM / B lymphocyte subpopulations in the acute phase of myocardial infarction are related to MRI-quantified infarcted mass

INTRODUÇÃO: A inflamação participa da fisiopatologia da aterosclerose humana e o papel dos subtipos de linfócitos B na massa infartada e lesão de reperfusão é pouco descrita na fase aguda do infarto do miocárdio. Este desfecho coronariano dispara ondas de mobilização de linfócitos que influenciam na resolução da lesão tecidual e massa final infartada, que geralmente se estabelece após as primeiras 4 semanas do infarto agudo do miocárdio com supradesnível do segmento ST (IAMCSST). OBJETIVOS: Quantificar subtipos de linfócitos B, B2 e B1 em pacientes com IAMCSST e verificar a relação destas com a massa de infarto 30 dias após evento. MÉTODOS: Amostras de sangue venoso foram coletadas nas primeiras 24 horas e no 30º dia do IAMCSST em pacientes do estudo BATTLE-AIM (n=86), que receberam estratégia fármaco-invasiva,seguida cateterismo nas primeiras 24h. O fenótipo das células foi determinado por citometria de fluxo. A produção espontânea de imunoglobulina M (IgM) pelos linfócitos B1, purificados após processo de "sorting", foi quantificada por ELISPOT. IgM plasmática foi determinada por ELISA. A massa de infarto do VE foi quantificada por ressonância nuclear magnética cardíaca...(AU)

Parameters of the Immune System and Vitamin D Levels in Old Individuals.

Aim: The increased number of individuals older than 80 years, centenarians, and supercentenarians is not a synonym for healthy aging, since severe infections, hospitalization, and disability are frequently observed. In this context, a possible strategy is to preserve the main characteristics/functions of the immune system with the aim to cause less damage to the organism during the aging process. Vitamin D acts on bone marrow, brain, breast, malignant cells, and immune system and has been recommended as a supplement. We aimed to evaluate whether immune parameters and vitamin D serum levels are correlated. Methods: We evaluated some features of the immune system using the peripheral blood of individuals older than 80 years (n = 12) compared to young subjects (n = 10). In addition, we correlated these findings with vitamin D serum levels. Results: Old individuals presented metabolic parameters of healthy aging and maintained preserved some features of immunity such as CD4/CD8 ratio, and low production of pro-inflammatory cytokines after stimulus. On the other hand, we observed increase in the frequency of myeloid-derived suppressor cells, reduction in circulating leukocytes, in the percentage of total CD8+, and in CD8+ Naïve T cells, in addition to increase in the percentage of CD8+ effector memory re-expressing CD45RA (EMRA) T cells. We found seropositivity for CMV in 97.7%, which was correlated with the decrease of CD8+ Naïve T cells and increase in CD8+ EMRA T cells. Vitamin D levels were insufficient in 50% of old individuals and correlated positively with total CD8+ T cells and negatively with CD8+ EMRA T cells. Conclusion: In the studied population, longevity was correlated to maintenance of some immune parameters. Considering the limitations of the study as size of the sample and lack of functional assays, it was found that vitamin D in old individuals was correlated to some features of the immune system, mainly in the CD8 compartment.

Propionibacterium acnes Enhances the Immunogenicity of HIVBr18 Human Immunodeficiency Virus-1 Vaccine.

Immunization of BALB/c mice with HIVBr18, a DNA vaccine containing 18 CD4+ T cell epitopes from human immunodeficiency virus (HIV), induced specific CD4+ and CD8+ T cell responses in a broad, polyfunctional and persistent manner. With the aim of increasing the immunogenicity of this vaccine, the effect of Propionibacterium acnes as an adjuvant was evaluated. The adjuvant effects of this bacterium have been extensively demonstrated in both experimental and clinical settings. Herein, administration of two doses of HIVBr18, in the presence of P. acnes, increased the proliferation of HIV-1-specific CD4+ and CD8+ T lymphocytes, the polyfunctional profile of CD4+ T cells, the production of IFN-γ, and the number of recognized vaccine-encoded peptides. One of the bacterial components responsible for most of the adjuvant effects observed was a soluble polysaccharide extracted from the P. acnes cell wall. Furthermore, within 10 weeks after immunization, the proliferation of specific T cells and production of IFN-γ were maintained when the whole bacterium was administered, demonstrating a greater effect on the longevity of the immune response by P. acnes. Even with fewer immunization doses, P. acnes was found to be a potent adjuvant capable of potentiating the effects of the HIVBr18 vaccine. Therefore, P. acnes may be a potential adjuvant to aid this vaccine in inducing immunity or for therapeutic use.

Improvement of Mesenchymal Stem Cell Immunomodulatory Properties by Heat-Killed Propionibacterium acnes via TLR2.

Mesenchymal stem cells (MSCs) are an essential tool for regenerative medicine, which aims to develop new technologies to improve their effects to obtain useful transplantation results. MSC immunomodulatory role has been just demonstrated; however, how they react when they are stimulated by an adjuvant is poorly understood. Our group showed the adjuvant effect of killed Propionibacterium acnes (P. acnes) on hematopoietic stem cells. As these cells share the same MSCs bone marrow (BM) site and interact with each other, here we evaluated the P. acnes and its soluble polysaccharide (PS) effect on MSCs and their immunomodulatory role in a murine model of traumatic brain injury (TBI). The bacteria increased the absolute number of MSCs, including MSC subpopulations, and maintained MSC plasticity. P. acnes and PS enhanced MSC proliferation and improved their immunomodulatory effect. P. acnes-MSC and PS-MSC transplantation increased anti-inflammatory cytokine expression and diminished pro-inflammatory cytokine expression after injury. This effect seemed to be mediated via TLR2 since P. acnes-KOTLR2-MSC transplantation decreased TGF-ß and IL-10 expression. Increasing in neural stem cells and neuroblasts after PS-MSC transplantation was also observed. The adjuvant effect of P. acnes is an alternative means of expanding MSCs and important to identify their subpopulations to know better their role under exogenous stimuli including inflammation resolution in an experimental model.

Propionibacterium acnes induces an adjuvant effect in B-1 cells and affects their phagocyte differentiation via a TLR2-mediated mechanism.

B-1 lymphocytes are present in large numbers in the mouse peritoneal cavity, as are macrophages, and are responsible for natural IgM production. These lymphocytes migrate to inflammatory foci and are also involved in innate immunity. It was also demonstrated that B-1 cells are able to differentiated into phagocytes (B-1CDP), which is characterized by expression of F4/80 and increased phagocytic activity. B-1 cell responses to antigens and adjuvants are poorly characterized. It has been shown that Propionibacterium acnes suspensions induce immunomodulatory effects in both macrophages and B-2 lymphocytes. We recently demonstrated that this bacterium has the ability to increase B-1 cell populations both in vitro and in vivo. P. acnes induces B-1CDP differentiation, increases the expression of TLR2, TLR4 and TLR9 and augments the expression of CD80, CD86 and CD40 in B-1 and B-1CDP cells. Because P. acnes has been shown to modulate TLR expression, in this study, we investigated the role of TLR2 and TLR4 in B-1 cell population, including B-1CDP differentiation and phagocytic activity in vitro and in vivo. Interestingly, we have demonstrated that TLR2 signaling could be involved in the increase in the B-1 cell population induced by P. acnes. Furthermore, the early differentiation of B-1CDP is also dependent of TLR2. It was also observed that TLR signals also interfere in the phagocytic ability of B-1 cells and their phagocytes. According to these data, it is clear that P. acnes promotes an important adjuvant effect in B-1 cells by inducing them to differentiate into B-1CDP cells and modulates their phagocytic functions both in vivo and in vitro. Moreover, most of these effects are mediated primarily via TLR2. These data reinforce the findings that such bacterial suspensions have powerful adjuvant properties. The responses of B-1 cells to exogenous stimulation indicate that these cells are important to the innate immune response.

Modulation of Th1/Th2 immune responses by killed Propionibacterium acnes and its soluble polysaccharide fraction in a type I hypersensitivity murine model: induction of different activation status of antigen-presenting cells.

Propionibacterium acnes (P. acnes) is a gram-positive anaerobic bacillus present in normal human skin microbiota, which exerts important immunomodulatory effects, when used as heat- or phenol-killed suspensions. We previously demonstrated that heat-killed P. acnes or its soluble polysaccharide (PS), extracted from the bacterium cell wall, suppressed or potentiated the Th2 response to ovalbumin (OVA) in an immediate hypersensitivity model, depending on the treatment protocol. Herein, we investigated the mechanisms responsible for these effects, using the same model and focusing on the activation status of antigen-presenting cells (APCs). We verified that higher numbers of APCs expressing costimulatory molecules and higher expression levels of these molecules are probably related to potentiation of the Th2 response to OVA induced by P. acnes or PS, while higher expression of toll-like receptors (TLRs) seems to be related to Th2 suppression. In vitro cytokines production in cocultures of dendritic cells and T lymphocytes indicated that P. acnes and PS seem to perform their effects by acting directly on APCs. Our data suggest that P. acnes and PS directly act on APCs, modulating the expression of costimulatory molecules and TLRs, and these differently activated APCs drive distinct T helper patterns to OVA in our model.