GJB5 association with BRAF mutation and survival in cutaneous malignant melanoma

BACKGROUND

Gap junctional intercellular communication is crucial for epidermal cellular homeostasis. Inability to establish melanocyte-keratinocytes contacts and loss of intercellular junction's integrity may contribute to melanoma development. Connexins, laminins and desmocollins have been implicated in the control of melanoma growth, where their reduced expression has been reported in metastatic lesions.

OBJECTIVES

The aim of this study was to investigate Connexin 31.1 (GJB5) expression and identify any association with BRAF mutational status, melanoma patient prognosis and MAPK inhibitors (MAPKi) treatment.

MATERIAL AND METHODS

GJB5 expression was measured at RNA and protein level in melanoma clinical samples and established cell lines treated or not with BRAF and MEK inhibitors, as well as in cell lines which developed MAPK inhibitors resistance. Findings were further validated and confirmed by analysis of independent datasets.

RESULTS

Our analysis reveals significant downregulation of GJB5 expression in metastatic melanoma lesions compared to primary ones and in BRAF mutated versus BRAF wild-type melanomas. Likewise, GJB5 expression is significantly lower in BRAF^V600E compared with BRAF^WT cell lines and increases upon MAPKi treatment. MAPKi-resistant melanoma cells display a similar expression pattern compared to BRAF^WT cells, with increased GJB5 expression associated with morphological changes. Enhancement of BRAF^V600E expression in BRAF^WT melanoma cells significantly upregulates miR-335-5p expression with consequent downregulation of GJB5, one of its targets. Furthermore, overexpression of miR-335-5p in two BRAF^WT cell lines confirms specific GJB5 protein downregulation. RT-qPCR analysis also revealed upregulation of miR-335 in BRAF^V600E melanoma cells, which is significantly downregulated in cells resistant to MEK inhibitors. Our data were further validated using the TCGA-SKCM dataset, where BRAF mutations associate with increased miR-335 expression and inversely correlate with GJB5 expression. In clinical samples, GJB5 underexpression is also associated with patient overall worse survival, especially at early stages.

CONCLUSION

We identified a significant association between metastases / BRAF mutation and low GJB5 expression in melanoma. Our results identify a novel mechanism of Gap-junctional protein regulation, suggesting a prognostic role for GJB5 in cutaneous melanoma.

Prevalence and incidence of osteoporotic fractures in patients on long-term glucocorticoid treatment for rheumatic diseases: the Glucocorticoid Induced OsTeoporosis TOol (GIOTTO) study

Osteoporosis and fractures are common and invalidating consequences of chronic glucorticoid (GC) treatment. Reliable information regarding the epidemiology of GC induced osteoporosis (GIOP) comes exclusively from the placebo group of randomized clinical trials while observational studies are generally lacking data on the real prevalence of vertebral fractures, GC dosage and primary diagnosis. The objective of this study was to evaluate the prevalence and incidence of osteoporotic fractures and to identify their major determinants (primary disease, GC dosage, bone mineral density, risk factors, specific treatment for GIOP) in a large cohort of consecutive patients aged >21 years, on chronic treatment with GC (≥5 mg prednisone - PN - equivalent) and attending rheumatology centers located all over Italy. Glucocorticoid Induced OsTeoporosis TOol (GIOTTO) is a national multicenter cross-sectional and longitudinal observational study. 553 patients suffering from Rheumatoid Arthritis (RA), Polymyalgia Rheumatica (PMR) and Connective Tissue Diseases (CTDs) and in chronic treatment with GCs were enrolled. Osteoporotic BMD values (T score <-2.5) were observed in 28%, 38% and 35% of patients with CTDs, PMR or RA at the lumbar spine, and in 18%, 29% and 26% at the femoral neck, respectively. Before GC treatment, prevalent clinical fractures were reported by 12%, 37% and 17% of patients with CTDs, PMR, or RA, respectively. New clinical fragility fractures during GC treatment were reported by 12%, 10% and 23% of CTDs, PMR and RA patients, respectively. Vertebral fractures were the prevailing type of fragility fracture. More than 30% of patients had recurrence of fracture. An average of 80% of patients were in supplementation with calcium and/or vitamin D during treatment with GCs. Respectively, 64%, 80%, and 72% of the CTDs, PMR and RA patients were on pharmacological treatment for GIOP, almost exclusively with bisphosphonates. The GIOTTO study might provide relevant contributions to clinical practice, in particular by highlighting and quantifying in real life the prevalence of GIOP and relative fractures, the frequency of the main risk factors, and the currently sub-optimal prevention. Moreover, these results emphasize the importance of the underlying rheumatic disease on the risk of GIOP associated fractures.

A Novel Multi-step Virtual Screening for the Identification of Human and Mouse mPGES-1 Inhibitors

We present here the development of a novel virtual screening protocol combining Structure-based and Ligand-based drug design approaches for the identification of mouse mPGES-1 inhibitors. We used the existing 3D structural data of the murine enzyme to hypothesize the inhibitors binding mode, which was the starting point for docking simulations, shape screening, and pharmacophore hypothesis screening. The protocol allowed the identification of 16 mouse mPGES-1 inhibitors with low micromolar activity, which, notably, also inhibit the human enzyme in the same concentration range. The inhibitors predicted binding mode is expected to be the base for the rational drug design of new potent dual species inhibitors of human and murine mPGES-1.

Articular and other Immune-Mediated Extra-Intestinal Manifestations in Inflammatory Bowel Diseases

The articular involvement in patients with inflammatory bowel diseases is included in the group of immune-mediated extra-intestinal manifestations, occurring approximately in a range from 6.2–36% of the patients. This group is also made up of the skin and eyes manifestations, that usually but not invariably are correlated with intestinal inflammatory disease activity. Rheumatic manifestations are the most frequent extra-intestinal findings of this group with a prevalence from 20–50%. They are divided into two different clinical subsets: peripheral and axial joint involvement (including sacroiliitis with or without spondylitis). Peripheral arthritis is the most frequent finding in both Crohn's disease and ulcerative colitis, occurring with a frequency ranging from 17–20%, and it is more common in Crohn's disease. Axial involvement is more common in Crohn's disease (5–22%) than in ulcerative colitis (2–6%) and generally the prevalence of sacroiliitis (asymptomatic and symptomatic) is between 12–20% and of spondylitis is between 2–16%. The IBD is also associated with other rheumatic diseases such as rheumatoid arthritis, Sjogren syndrome, Takayasu arteritis and fibromyalgia. The management of patients with EA requires an active cooperation between gastroenterologists and rheumatologists.

[Type I cryoglobulinemia with a fatal outcome]

Type I cryoglobulinemia, a condition associated with lymphoproliferative disorders, is caused by monoclonal immunoglobulins that precipitate at low temperatures. It mostly involves the skin and pathology study shows no signs of vasculitis. Management is usually based on immunosuppressive drugs associated with plasmapheresis for severe disease. The use of rituximab has recently been described for resistant cases. We present an unusual case of long-standing type I cryoglobulinemia associated with a monoclonal gammopathy of unknown significance. The patient developed extremely severe skin lesions with histological signs of vasculitis. The patient died due to the onset of noncutaneous manifestations of the cryoglobulinemia and complications of the immunosuppressive treatment.

Insulin regulates IL-1alpha, Ifn-y and IL-4 release from murine splenocytes stimulated with staphylococcal protein A, toxic shock syndrome toxin-1 and streptococcal lysin S

In this study, changes were investigated in release of IL-1alpha, IFN-gamma and IL-4 from mouse splenocytes stimulated with staphylococcal protein A (SpA), toxic shock syndrome toxin-1 (TSST-1) or streptococcal lysin S (SLS) in the presence of insulin. The results show that insulin-treated splenocytes stimulated by SpA had a 25% increase in IFN-gamma release and a 50% decrease in IL-4 compared with splenocytes treated with SpA alone. IL-1alpha release was unchanged compared with controls. Insulintreated splenocytes stimulated with TSST-1 had a 30% fall in IL-1alpha and IFN-gamma release compared with controls. There were no changes in IL-4 release. Splenocytes stimulated with SLS after insulin treatment increased their release of IL-1alpha and IFN-gamma by 50%, whereas IL-4 release was unchanged. The data suggest that the insulin may have important functional implications in immunoregulation.

Interleukin-8 production by THP-1 cells stimulated by Salmonella enterica serovar Typhimurium porins is mediated by AP-1, NF-κB and MAPK pathways

Interleukin-8 (IL-8) is released in response to inflammatory stimuli, such as bacterial products. Either porins or lipopolysaccharide (LPS) stimulated THP-1 cells to release IL-8 after 24 h. We have previously reported that stimulation of monocytic cells with Salmonella enterica serovar Typhimurium porins led to the activation of mitogen-activated protein kinase cascades and of protein tyrosine kinases (PTKs). In this report, we demonstrate, using two potent and selective inhibitors of MEK activation by Raf-1 (PD-098059) and p38 (SB-203580), that both ERK1/2 and p38 pathways play a key role in the production of IL-8 by porins and LPS. Porin-stimulated expression of activating protein 1 (AP-1) and correlated IL-8 release is also inhibited by PD-098059 or SB-203580 indicating that the Raf-1/MEK1-MEK2/MAPK cascade is required for their activation. Also PTKs modulate the pathway that control IL-8 gene expression, in fact its expression is abolished by tyrphostin. By using N-acetyl-leucinyl-leucinyl-norleucinal-H (ALLN) an inhibitor of nuclear factor-kappaB (NF-kappaB) activity, we also observed IL-8 release modulation. Our results elucidate some of the molecular mechanisms by which AP-1 and NF-kappaB regulate IL-8 release and open new strategies for the design of specific molecules that will modulate IL-8 effects in various infectious diseases.

Monocytic activation of protein tyrosine kinase, protein kinase A and protein kinase C induced by porins isolated from Salmonella enterica serovar Typhimurium

OBJECTIVES

In the present study a monocytic cell line, U937, was used to investigate the possible involvement of protein tyrosine kinases (NT-PTKs), protein kinase A (PKA) and protein kinase C (PKC) in cell signaling pathways following Salmonella enterica serovar Typhimurium porin stimulation.

METHODS

Different concentrations of porins and lipopolysaccharide (LPS) were analysed to evaluate changes in PTK activity by a non radioactive tyrosine kinase assay and in PKA and PKC phosphorylation by Western blotting analysis. The inhibitors of PTK, PKA and PKC activation used, were: 3,4-dihydroxybenzylidene-malononitrile (tyrphostin 23), inhibitor of epidermal growth factor (EGF) receptor tyrosine kinase activity; dihychloride (H-89), a selective inhibitor of PKA which is useful to discriminate between the effects of PKC and PKA; diacylglycerol kinase inhibitor II (R59949), which is useful for elucidating roles of PKC; calphostin C, a specific inhibitor of PKC.

RESULTS

Porins of the outer membrane of the ST were isolated to be used as a stimulus in the performed experiments. Following porin treatment, a dose-dependent increase in PTK, PKA and PKC activation was observed. U937 monocytes pretreated with inhibitors induced an evident decrease in PTK activity and PKA and PKC phosphorylation pattern in porin stimulated monocytes.

CONCLUSIONS

Our data support the important role played by NT-PTK, PKA and PKC in transducing the activating signal in macrophages stimulated with porins through the activation of the mitogen-activated protein kinase (MAPK) pathway that participate in the regulation of gene expression.

p53 and c-myc activation by Pasteurella haemolytica leukotoxin is correlated with bovine mononuclear cells apoptosis

To analyse the role of Pasteurella haemolytica Leukotoxin (LKT) in the mechanism of apoptotic cell death of bovine lymphocytes, we evaluated DNA fragmentation and p53 and c-myc expression. P. haemolytica strain ATCC 14003 was cultivated for LKT production. DNA fragmentation was analysed by electrophoresis on Agarose gel. DNA strand breaks in individual apoptotic cells were also detected by an in situ Terminal deoxy nucleotidyl Transferase (TdT). The Polymerase Chain Reaction (PCR) procedure was used for verified p53 and c-myc activation by P. haemolytica LKT. LKT was able to induce DNA fragmentation in a dose and time-dependent fashion. The greatest apoptotic effect was obtained using LKT at a concentration of 0.25 U. The results show that p53 and c-myc activation by LKT is correlated with apoptosis of bovine lymphocytes and monocytes. Our data suggest that LKT may have an important role in the bacterial virulence of Pasteurella haemolytica.

Induction of tyrosine phosphorylated proteins in THP-1 cells by Salmonella typhimurium, Pasteurella haemolytica and Haemophilus influenzae porins

The effect of porins purified from Salmonella typhimurium, Pasteurella haemolytica and Haemophilus influenzae on induction of tyrosine phosphorylation in THP-1 cells and C3H/HeJ macrophage was investigated. Incubation of porins at concentration of 1.0-5.0 microg ml(-1) with either THP-1 or macrophage from C3H/HeJ mice resulted in tyrosine phosphorylation of specific host cell proteins. After porin stimulation a pattern of tyrosine phosphorylated proteins appeared in the soluble cytoplasmic fraction, in the membrane fraction and in the insoluble protein fraction. The observed effects were dependent on the porin concentrations; they reached a maximal expression at 3 min and declined at 60 min. Porin and lipopolysaccharide treatments induce a similar phosphorylation pattern in all of the three cellular fractions studied. A difference can be observed in the cytoplasmic fraction bands of 50-60 kDa, which are more evident after treatment with lipopolysaccharide, and in the insoluble fraction band of 80 kDa and the cytoplasmic fraction band of 250 kDa, which are more evident after treatment with porins. The events of tyrosine protein phosphorylation were present in macrophage from lipopolysaccaride-hyporesponsive C3H/HeJ mice stimulated with porins, while they were markedly reduced when the cells were stimulated with lipopolysaccharide. Staurosporine, genistein and cytochalasin D induced in the three cellular fractions a different inhibition pattern of tyrosine protein phosphorylation in porin stimulated cells. Porins extracted from the three bacterial species investigated behave in a similar way as stimuli more or less potent; Hib porin seems to be the most powerful stimulator and, moreover, it specifically induces phosphorylation of a 55 kDa band.

Haemophilus influenzae porin contributes to signaling of the inflammatory cascade in rat brain

In the present study we observed that the Haemophilus influenzae type b (Hib) porin, among the different surface bacterial components, is involved in the pathophysiology of bacterial meningitis. This study demonstrates that inoculation of Hib porin into the fourth cerebral ventricle causes the simultaneous expression of interleukin-1alpha (IL-1alpha), tumor necrosis factor alpha (TNF-alpha), and macrophage inflammatory protein 2 (MIP-2) at 6 h after inoculation. At 24 h, the expression of MIP-2 decreases while the expression of IL-1alpha and TNF-alpha increases. The mRNA expression of IL-1alpha, TNF-alpha, and MIP-2 is correlated with injury to the blood-brain barrier as demonstrated by the appearance of serum proteins and leukocytes in cerebrospinal fluid and by the increase in brain water content.

HSP and apoptosis in leukocytes from infected or vaccinated animals by Brucella abortus

The production of hsp and apoptosis of leukocytes in the peripheral blood of animals naturally infected with Brucella spp or treated with the vaccine Brucella abortus 19 have been investigated in this study. Cytokines able to induce phagocytic activity in macrophages of non treated healthy animals were found in the supernatant of bovine leukocytes cultivated in vitro. A long-lasting antibody response against hsp 60 kDa and 27 kDa, which lasts a long time, is induced in naturally infected animals, while in animals vaccinated with B. abortus 19 we detected an antibody response against hsp 60 and 70 kDa which is much shorter, disappearing in two months. During the early phase of infection, lymphocytes and monocytes of naturally infected animals show a delay of apoptosis in vitro compared to the same cells coming from healthy controls and vaccinated animals.

Role of Pasteurella multocida, Pasteurella haemolytica and Salmonella typhimurium porins on inducible nitric oxide release by murine macrophages

The aim of this study was to verify whether Pasteurella haemolytica, P. multocida and Salmonella typhimurium porins could affect the inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) release by murine resident peritoneal macrophages in vitro. We also compared their effect with that elicited by P. haemolytica, P. multocida and S. typhimurium lipopolysaccharide (LPS) whose biological activity is well known. Variations in NO release and iNOS mRNA expression due to variable concentrations of porins were recorded and compared. We also investigated the synergism between bacterial products and interferon gamma (IFN-gamma). With this aim cells were incubated with porins together with murine rIFN-gamma prior to assessing the presence of NO in the supernatant and mRNA analysis. Porins in themselves were not able to induce NO release by resident peritoneal macrophages. Incubation of macrophages with IFN-gamma in the presence of porins increased NO release, whereas incubation in the presence of the arginine analog N(G)-monomethyl-L-arginine (NMA) inhibited NO release. The greatest NO release was obtained using porins at a concentration of 5 microg/mL. Porins, together with IFN-gamma, were also able to upregulate the mRNA expression of iNOS. Our findings suggest that gram-negative porins are able to modulate inflammatory and immunological responses by affecting the release of NO and the expression of iNOS gene in activated macrophages.

Role of Pasteurella multocida porin on cytokine expression and release by murine splenocytes

The aim of this study was to verify whether Pasteurella multocida porin can affect the expression and release of IL-1alpha, IL-6, TNF-alpha, IL-4, IFN-gamma, IL-10 and IL-12 by murine splenocytes in vitro. P. multocida porin and lipopolysaccharide (LPS) were able to induce the release of IL-1alpha, IL-6, TNF-alpha, IFN-gamma and IL-12 in a dose-dependent fashion. The greatest release of these cytokines was obtained using P. multocida porin at a concentration of 5 microg ml(-1) and LPS at a concentration of 1 microg ml(-1). The time-courses of release showed that P. multocida LPS was able to stimulate the production of IL-1alpha, IL-6, TNF-alpha, IFN-gamma and IL-12 earlier than porin and at a greater rate. No effect was observed on IL-4 and IL-10 release under the same experimental conditions. P. multocida porin and LPS were also able to up-regulate the mRNA expression of IL-1alpha, IL-6, TNF-alpha, IFN-gamma and IL-12 p40. Our findings suggest that P. multocida porin is able to modulate inflammatory and immunological responses by affecting the release of several cytokines and the expression of their genes.

Effects of the major Pasteurella multocida porin on bovine neutrophils

OBJECTIVE

To evaluate in vitro effect of the major fraction of outer membrane proteins of Pasteurella multocida with porin-like activities on some biological functions of bovine neutrophils.

ANIMALS

Neutrophils from 5 adult cattle.

PROCEDURE

Variations in such biological processes as actin polymerization and chemotaxis and evaluation of hydrogen peroxide attributable to variable concentrations of P multocida were recorded and compared. Data were obtained, using the porin and lipopolysaccharide (LPS) isolated from a strain of P multocida cultivated in brain-heart infusion (BHI) broth. Various concentrations of porin and LPS were analyzed to evaluate changes in functional activation and microbicidal activity of bovine neutrophils.

RESULTS

The 37.5-kd major polypeptide of the outer membrane of P multocida was isolated. Presence of this porin was significantly correlated with variations of some biological functions of bovine neutrophils. These immunocompetent cells had a concentration-dependent increase in actin polymerization and chemotactic activity. A concentration-dependent variation in the oxidative burst also was observed.

CONCLUSIONS

The porins of gram-negative bacteria affect several biological functions of cells involved in the immune response as well as in inflammation. Significant correlation of results of in vitro experiments also was identified between porin and LPS effect. Pretreatment of bovine neutrophils with various concentrations of porin always caused a concentration-dependent increase in examined biological activities.

Th1 and Th2 cell involvement in immune response to Salmonella typhimurium porins

In understanding the regulation of the specific immune response to Salmonella typhimurium, the role of a surface major component (porins) was studied. In this study we demonstrate that purified porins are able to induce a different response to that induced by the porins present on the S. typhimurium cell surface. Porin-treated or orally infected mice show anti-porin antibodies with bactericidal activity. The complete adoptive transfer of resistance to S. typhimurium is achieved only using splenic T cells from survivor mice after experimental infection. After stimulation with specific antigen in vitro CD4+ cells from porin-immunized mice released large amounts of interleukin-4 (IL-4), at a time when CD4+ cells from S. typhimurium-infected mice predominantly secreted interferon-gamma (IFN-gamma). Limiting dilution analysis showed that infection resulted in a higher precursor frequency of IFN-gamma-producing CD4+ T cells and a lower precursor frequency of IL-4-producing CD4+ T cells, while immunization with porins resulted in a higher precursor frequency of IL-4-producing cells and a low frequency of IFN-gamma-producing cells. Analysis of polymerase chain reaction-amplified cDNA from the spleens of infected mice revealed that IFN-gamma, IL-2 and IL-12 p40 mRNA were found 5 days after in vitro challenge and increased after 15 days; IL-10 expression was barely present after both 5 and 15 days, while IL-4 mRNA expression was not detected. In immunized mice, the IL-4 mRNA expression increased after 15 days, IFN-gamma mRNA expression disappeared entirely after 15 days, while IL-2, IL-10 and IL-12 mRNA remained relatively unchanged.

Effect of Pasteurella haemolytica outer membrane proteins on bovine neutrophils

The major outer membrane proteins (OMPs) isolated from Pasteurella haemolytica induce alterations of the biological activity of bovine polymorphonuclear leukocytes (PMNs). A dose-dependent reduction of the capacity of adherence to nylon wool in vitro was observed. OMPs also acted as chemotaxins at concentrations between 5 and 20 microg/ml. Concentrations lower than 5 microg/ml did not give considerable results. Preincubation with 5 microg/ml of OMPs led to modifications in the values of the phagocytic index and of intracellular killing, which were found to be diminished with respect to controls.

Polyclonal T cell elimination by prolonged immunostimulation in an experimental model

An experimental model of immunological deficiency obtained by treating mice for 6 months with serum of human blood drawn from different healthy individuals has been studied. The results show that an alteration of a circulating lymphocyte population with alterations of the ratio CD4+/CD8+ appeared in mice stimulated for a long period with immunogens. Mice treated for 2-4 months showed an increase in B lymphocytes and a decrease in the total number of T lymphocytes, with a decrease in CD4+ lymphocytes and an increase in CD8+ lymphocytes. After 4 months, the CD8+ lymphocyte population started to decrease, with a ratio of CD4+/CD8+ reaching almost 1. In animals treated for 2-3 months, the mean survival time (MST) following experimental infection with Salmonella typhimurium presented a decrease to 5 days, and after 5-6 months of treatment presented a decrease to 3-2.5 days. The bacteraemia was modified in comparison with controls. Prolonged exposure to antigens also induced lymphocyte apoptosis: cells of animals treated for 4-6 months presented increased levels of apoptosis with a percentage that reached 30-35%. A semiquantitative evaluation of the level of heat shock protein (hsp) in splenic lymphocytes showed an increase in the presence of hsp60 and hsp70 in the first 3 months of treatment, which then remained constant for up to 6 months.

Growth hormone release of interleukin-1 alpha, interferon-gamma and interleukin-4 from murine splenocytes stimulated with staphylococcal protein A, toxic shock syndrome toxin-1 and streptococcal lysin S

We investigated changes in the IL-1 alpha, IFN-gamma and IL-4 release from splenocytes in the presence of growth hormone (GH). Splenocytes were stimulated with Protein A (PA), Toxic Shock Syndrome Toxin-1 (TSST-1) and Streptolysin S (SLS). In the presence of GH, splenocytes stimulated with PA, induced a 40% and 50% drop in IL-1 alpha and IFN-gamma release respectively, compared to controls, while no changes were shown in IL-4 release. The release of IFN-gamma by TSST-1-stimulated splenocytes fell by 30%, while no changes were shown in IL-1 alpha and IL-4 release after GH. The release of IL-1 alpha by SLS-stimulated splenocytes increased by 50% in the presence of GH. No changes were shown in IFN-gamma and IL-4 release. The results are discussed in terms of the possibility of an expanding function for these endocrine peptides within the immune system.

Prolactin regulates IL-1 alpha, IFN-gamma and IL-4 release from mouse splenocytes stimulated with some staphylococcal and streptococcal toxins

This study investigates changes in IL-1 alpha, IFN-gamma and IL-4 from mouse splenocytes stimulated with Staphylococcal Protein A (PA), or Toxic Shock Syndrome Toxin-1 (TSST-1), or Streptococcal lysin S (SLS) after exposure to Prolactin (PRL). In the presence of PRL, IL-1 alpha and IFN-gamma induction by PA-stimulated splenocytes was reduced by 74% and 25% respectively. On the other hand, IL-4 release was enormously increased. The ability of TSST-1 to induce IFN-gamma release was decreased by 32% after PRL. IL-1 alpha and IL-4 was unchanged compared to controls. In the presence of PRL, IFN-gamma release from splenocytes stimulated with SLS, was increased by 60%, while no changes were shown in IL-1 alpha and IL-4 release.

Presence of Legionella spp. in thermal springs of the Campania region of south Italy

Water samples from 66 thermal springs in the Campania region of South Italy were cultured for Legionella spp., Pseudomonas aeruginosa, and indicators of faecal pollution. The temperature of the sources ranged from 21 degrees C to 59.5 degrees C. Legionella pneumophila, serogroup 7-10, was isolated from two out of 60 sources on the Island of Ischia and Legionella dumoffii from one mainland source. The temperatures of these sources were 35.2 degrees C, 48.2 degrees C, and 52.0 degrees C respectively. Twelve sources were positive for P. aeruginosa and 6 for Escherichia coli. Our results found that Legionella spp. were present in only three thermal springs, indicating that in the hydrothermal area of the Campania region the presence of this microbial species is very scarce.

Growth hormone modulates IL-alpha and IFN-gamma release by murine splenocytes activated by LPS or porins of Salmonella typhimurium

The effect of growth hormone (GH) on the release of IL-1alpha and IFN-gamma from murine splenocytes was investigated. Their release from splenocytes activated by Salmonella enterica serovar Typhimurium lipopolysaccharide (LPS) 0.5 microg/ml was increased by c. 65% in the presence of GH 100 pg/ml. With splenocytes activated by S. Typhimurium porins 5 microg/ml, GH increased the production of both IL-1alpha and IFN-gamma by c. 56%. Polymyxin treatment abolished the cytokine-releasing activity of LPS but had no effect on the activity of the porin preparation.

Prolactin and insulin regulate the release of IL-1-alpha and IFN-gamma from murine splenocytes activated with porins or LPS of Salmonella typhimurium

Murine splenocytes treated with prolactin (PRL) or insulin were stimulated in vitro with porins or lipopolysaccharide (LPS) of Salmonella typhimurium. It was seen that PRL inhibits the release of IFN-gamma from splenocytes treated with porins by about 20% while having no effect on the release of IL-1-alpha. Splenocytes porin-stimulated splenocytes exhibited a remarkable increase in IL-1-alpha release (100%) and a diminished release of IFN-gamma (about 50%) in the presence of insulin. The splenocytes stimulated with LPS had a reduced release of IL-1-alpha (75%) and IFN-gamma (about 50%) when insulin was added. The data suggest that classical endocrine system participates in a bioregulatory feedback loop that may prevent unwanted toxicity from cytokine excess. However, some bacterial products sometimes enormously unbalance this regulatory network.