Monocyte phenotypes: when local education counts

Monocytes are a heterogeneous population of phagocytic cells that are generated in the bone marrow and released into the bloodstream. There are two main monocyte subsets in mice: “inflammatory” monocytes that are Ly6Chi CCR2hi CX3 CR1low and “alternative” or “patrolling” monocytes that are Ly6Clow CCR2low CX3 CR1hi. The process of monocyte recruitment and differentiation is still a matter of controversy. In this issue, Dal-Secco et al. report in situ monocyte reprogramming in the liver, from proinflammatory CCR2hi CX3 CR1low cells into reparative CCR2low CX3 CR1hi cells and show, for the first time, that this occurs at the site of injury.Fil: Quintar, Amado Alfredo. la Jolla Institute For Allergy And Immunology; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hedrick, Catherine C. . la Jolla Institute For Allergy And Immunology; Estados UnidosFil: Ley, Klaus. la Jolla Institute For Allergy And Immunology; Estados Unido

Regulation of surfactant protein D in the rodent prostate

<p>Abstract</p> <p>Background</p> <p>Surfactant protein D (SP-D) is an innate immune protein that is present in mucosal lined surfaces throughout the human body, including the male reproductive tract. In the present study, we characterized the regulation of SP-D expression in the mouse and rat prostate.</p> <p>Methods</p> <p>Real time reverse transcriptase polymerase chain reaction (RT-PCR) and immunostaining were used to characterize SP-D mRNA and protein in the mouse male reproductive tract. In order to evaluate the effects of testosterone on SP-D gene expression, we measured SP-D mRNA levels via real time RT-PCR in prostates from sham-castrated mice and castrated mice. In addition, we used a rat prostatitis model in which Escherichia coli was injected into the prostate in vivo to determine if infection influences SP-D protein levels in the prostate.</p> <p>Results</p> <p>We found that SP-D mRNA and protein are present throughout the mouse male reproductive tract, including in the prostate. We determined that castration increases prostate SP-D mRNA levels (~7 fold) when compared to levels in sham-castrated animals. Finally, we demonstrated that infection in the prostate results in a significant increase in SP-D content 24 and 48 hours post-infection.</p> <p>Conclusion</p> <p>Our results suggest that infection and androgens regulate SP-D in the prostate.</p

Dedifferentiation of prostate smooth muscle cells in response to bacterial LPS

Prostate smooth muscle cells (SMCs) are strongly involved in the development and progression of benign prostatic hyperplasia and prostate cancer. However, their participation in prostatitis has not been completely elucidated. Thus, we aimed to characterize the response of normal SMC to bacterial lipopolysaccharide (LPS). Methods Primary prostate SMCs from normal rats were stimulated with LPS (0.1, 1, or 10Âμg/ml) for 24 or 48hr. The phenotype was evaluated by electron microscopy, immunofluorescence, and Western blot of SMCα-actin (ACTA2), calponin, vimentin, and tenascin-C, while the innate immune response was assessed by immunodetection of TLR4, CD14, and nuclear NF-κB. The secretion of TNFα and IL6 was determined using ELISA. Results Bacterial LPS induces SMCs to develop a secretory phenotype including dilated rough endoplasmic reticulum cisternae with well-developed Golgi complexes. Furthermore, SMCs displayed a decrease in ACTA2 and calponin, and an increase in vimentin levels after LPS challenge. The co-expression of ACTA2 and vimentin, together with the induction of tenascin-C expression indicate that a myofibroblastic-like phenotype was induced by the endotoxin. Moreover, LPS elicited a TLR4 increase, with a peak in NF-κB activation occurring after 10min of treatment. Finally, LPS stimulated the secretion of IL6 and TNFα. ConclusionS Prostate SMCs are capable of responding to LPS in vitro by dedifferentiating from a contractile to a miofibroblastic-like phenotype and secreting cytokines, with the TLR4 signaling pathway being involved in this response. In this way, prostate SMCs may contribute to the pathophysiology of inflammatory diseases by modifying the epithelial-stromal interactions.Fil: Leimgruber, Carolina. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Quintar, Amado A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Sosa, Liliana del Valle. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: García, Luciana Noemí. Universidad Nacional de Córdoba; Argentina. Centro de Investigación de la Fundación Repro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Figueredo, Carlos Mauricio. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Maldonado, Cristina Alicia. Universidad Nacional de Córdoba. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentin

Androgen depletion augments antibacterial prostate host defences in rats

The defence of the male reproductive tract against microorganisms is critical for fertilization. The prostate gland has been reported to express several molecules of the innate immune system. However, little information is available about how androgens may modulate host defences within the prostate. We therefore aimed to examine in the rat the expression of the TLR4 system, which is strongly involved in pathogen recognition, and the secretion of the antibacterial substances rBD-1 and SP-D after androgen withdrawal. Immunoblotting and immunocytochemical analysis revealed a time-dependent increase in these molecules after orchiectomy, with epithelial and stromal cells being an important source of prostatic host defence proteins. In view of this, we evaluated the potential improvement in antibacterial ability of the prostatic fluid from orchiectomized animals ex vivo. Only samples from rats at 5 days postorchiectomy showed a slight inhibition of Escherichia coli growth. Finally, E. coli was inoculated into the ventral prostate of orchiectomized or control rats, with bacterial growth being counted at 5 days after infection. Animals with androgen depletion presented a lower bacterial count, and showed few histological signs of prostatic inflammation compared with controls. In vitro studies confirmed that isolated lipopolysaccharide (LPS)-treated prostatic cells in the absence of testosterone increased SP-D. Moreover, media from these cells showed a higher antimicrobial activity than supernatants from testosterone- and LPS-treated cells. Our findings indicate that testosterone maintains a reduced expression of key elements for innate immunity and diminishes the antibacterial ability of the rat prostate. These data may represent an important mechanism underlying the immunosuppressive activity of testosterone in the gland. However, this immunosuppressive function of androgens is understandable as a means of avoiding uncontrolled immune responses against the haploid male gamete in the reproductive tract.Fil: Quintar, Amado Alfredo. Universidad Nacional de Cordoba. Facultad de Medicina. Centro de Microscopia Electronica; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Leimgruber, Carolina. Universidad Nacional de Cordoba. Facultad de Medicina. Centro de Microscopia Electronica; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Pessah, O. A.. Universidad Nacional de Cordoba. Facultad de Medicina. Departamento de Medicina. Cat.de Bacteriologia y Virologia Medicas; ArgentinaFil: Doll, A.. Universidad Autonoma de Barcelona. Hospital Vall D; EspañaFil: Maldonado, Cristina Alicia. Universidad Nacional de Cordoba. Facultad de Medicina. Centro de Microscopia Electronica; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; Argentin

Galectins in Intestinal Inflammation: Galectin-1 Expression Delineates Response to Treatment in Celiac Disease Patients

Galectins, a family of animal lectins characterized by their affinity for N-acetyllactosamine-enriched glycoconjugates, modulate several immune cell processes shaping the course of innate and adaptive immune responses. Through interaction with a wide range of glycosylated receptors bearing complex branched N-glycans and core 2-O-glycans, these endogenous lectins trigger distinct signaling programs thereby controling immune cell activation, differentiation, recruitment and survival. Given the unique features of mucosal inflammation and the differential expression of galectins throughout the gastrointestinal tract, we discuss here key findings on the role of galectins in intestinal inflammation, particularly Crohn’s disease, ulcerative colitis, and celiac disease (CeD) patients, as well as in murine models resembling these inflammatory conditions. In addition, we present new data highlighting the regulated expression of galectin-1 (Gal-1), a proto-type member of the galectin family, during intestinal inflammation in untreated and treated CeD patients. Our results unveil a substantial upregulation of Gal-1 accompanying the anti-inflammatory and tolerogenic response associated with gluten-free diet in CeD patients, suggesting a major role of this lectin in favoring resolution of inflammation and restoration of mucosal homeostasis. Thus, a coordinated network of galectins and their glycosylated ligands, exerting either anti-inflammatory or proinflammatory responses, may influence the interplay between intestinal epithelial cells and the highly specialized gut immune system in physiologic and pathologic settings