Adjuvant Effect of Killed Propionibacterium acnes on Mouse Peritoneal B-1 Lymphocytes and Their Early Phagocyte Differentiation

B-1 lymphocytes are the predominant cells in mouse peritoneal cavity. They express macrophage and lymphocyte markers and are divided into B-1a, B-1b and B-1c subtypes. The role of B-1 cells is not completely clear, but they are responsible for natural IgM production and seem to play a regulatory role. An enriched B-1b cell population can be obtained from non-adherent peritoneal cell cultures, and we have previously demonstrated that these cells undergo differentiation to acquire a mononuclear phagocyte phenotype upon attachment to the substrate in vitro. Nevertheless, the B-1 cell response to antigens or adjuvants has been poorly investigated. Because killed Propionibacterium acnes exhibits immunomodulatory effects on both macrophages and B-2 lymphocytes, we analyzed whether a killed bacterial suspension or its soluble polysaccharide (PS) could modulate the absolute number of peritoneal B-1 cells in BALB/c mice, the activation status of these cells and their ability to differentiate into phagocytes in vitro. In vivo, P. acnes treatment elevated the absolute number of all B-1 subsets, whereas PS only increased B-1c. Moreover, the bacterium increased the number of B-1b cells that were positive for MHC II, TLR2, TLR4, TLR9, IL-4, IL-5 and IL-12, in addition to up-regulating TLR9, CD80 and CD86 expression. PS increased B-1b cell expression of TLR4, TLR9, CD40 and CD86, as well as IL-10 and IL-12 synthesis. Both of the treatments decreased the absolute number of B-1b cells in vitro, suggesting their early differentiation into B-1 cell-derived phagocytes (B-1CDP). We also observed a higher phagocytic activity from the phagocytes that were derived from B-1b cells after P. acnes and PS treatment. The adjuvant effect that P. acnes has on B-1 cells, mainly the B-1b subtype, reinforces the importance of B-1 cells in the innate and adaptive immune responses

Tumour macrophages as potential targets of bisphosphonates

Tumour cells communicate with the cells of their microenvironment via a series of molecular and cellular interactions to aid their progression to a malignant state and ultimately their metastatic spread. Of the cells in the microenvironment with a key role in cancer development, tumour associated macrophages (TAMs) are among the most notable. Tumour cells release a range of chemokines, cytokines and growth factors to attract macrophages, and these in turn release numerous factors (e.g. VEGF, MMP-9 and EGF) that are implicated in invasion-promoting processes such as tumour cell growth, flicking of the angiogenic switch and immunosuppression. TAM density has been shown to correlate with poor prognosis in breast cancer, suggesting that these cells may represent a potential therapeutic target. However, there are currently no agents that specifically target TAM's available for clinical use

Hodowla in vitro celomocytow dzdzownic Dendrobaena veneta

In vitro techniques are require to better understand coelomocytes - mediated immune responsed. The main obstacle in the long-term cultures of coelomocytes is the contamination with bacteria and fungi from earthworms exterior and coelomic cavity. To avoid this, coelomocytes are retrieved through a small incision in the body wall from earthworms maintained at 10°C for at least 2 weeks. Culture medium is supplemented with 1% streptomycin/penicylin (Sigma) and 0.001% thiomersal (Merck). Freshly retrieved coelomocytes of Dendrobaena veneta contain granular and non-granular cells in the proportion close to 1 : 1 while in our four-month in vitro culture granular cells predominate.Dla lepszego zrozumienia mechanizmów reakcji odpornościowych mediowanych przez celomocyty dżdżownic niezbędne są hodowle tych komórek w warunkach in vitro. Główną przeszkodą w długoterminowych hodowlach jest ich kontaminacja bakteriami i grzybami pochodzącymi z celomy i powierzchni ciała dżdżownic. Aby tego uniknąć, celomocyty pozyskujemy poprzez rozcięcie ściany ciała dżdżownic przetrzymywanych co najmniej dwa tygodnie w temperaturze 10°C. Pożywkę hodowlaną wzbogacamy 1% roztworem penicyliny/streptomycyny (Sigma) i 0,001% thiomersalem. Świeżo pobrane celomocyty Dendrobaena veneta zawierają komórki ziarniste jak i nieziarniste w proporcji zbliżonej do 1 : 1, podczas gdy w naszych hodowlach czteromiesięcznych przeważają komórki ziarniste

Cytocompatibility of aliphatic polyesters - in vitro study on fibroblasts and macrophages

A resorbable copolymer of glycolide and L-lactide (PGLA), a terpolymer of glycolide, L-lactide, and epsilon-caprolactone (PGLCL), and a copolymer of glycolide and E-caprolactone (PGCL) were synthesized by ring opening polymerization Using Zirconium acetylacetonate (Zr(acac)(4)) as an initiator. The Structure and physicochemical Surface properties of the materials were studied by NMR spectroscopy, gel permeation chromatography, differential scanning calorimetry, X-ray photoelectron spectroscopy, atomic force microscopy, and contact angle measurements. On the basis of contact angle measurements and the Owens-Wendt approach, the surface free energy Was calculated. The effect of polymeric films produced by solvent casting on morphology and activity of L929 fibroblasts, and two types of macrophages (macrophages from peritoneal exudates and RAW 264.7 monocytes/macrophages), was analyzed. It was found that viability, adhesion, and morphology of fibroblasts on PGLA were very similar to control glass. On PGLCL more adhering cells were round, while on PGCL only single, poorly spread cells were seen, and their viability was significantly reduced. This may Suggest that the interaction of fibroblasts with PGCL was due to its hydrophobicity and a very low polarity. Adhesion and viability of RAW 264.7 cells was significantly enhanced on PGLA but reduced on both PGLCL and PGCL. The increased synthesis/release of chemoattractants and metalloproteinases-2 and -9 was observed in the macrophages from peritoneal exudates cultured on PGLA and PGLCL The viability of cells decreased in the following order: PGLA > PGLCL > PGCL. It is worth noting that glass transition temperature and susceptibility to mechanical deformation of the polymeric materials also decreased in the same order. It may imply that those physical parameters should be also considered as potential factors affecting cell behavior. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 87A: 524-535, 200