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1.
Anaerobe ; 59: 141-144, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31254653

ABSTRACT

A retrospective study, including all samples tested for Clostridium difficile from 2015 to 2018, was conducted. 222 and 199 patients were respectively classified as having a mild/moderate or severe disease. A CT ≤ 26 was significantly associated with severe disease. Furthermore, low CT values were significantly associated to older patients and leukocytosis.


Subject(s)
Bacterial Proteins/genetics , Bacterial Toxins/genetics , Clostridium Infections/pathology , Polymerase Chain Reaction/methods , Aged , Aged, 80 and over , Humans , Male , Middle Aged , Retrospective Studies
2.
Clin Microbiol Infect ; 25(6): 761.e9-761.e13, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30315959

ABSTRACT

OBJECTIVES: Congenital toxoplasmosis (CT) affects one to ten fetuses per 10 000 live newborns in western countries. Without knowing pre-conception serostatus, it is hard to date the infection when anti-Toxoplasma IgG and IgM antibodies are positive at first screening. Although a high IgG avidity index (AI) in the first trimester excludes CT, the same cannot be said of intermediate and low AI. The aim of this study was to estimate the risk of CT when intermediate or low AI is detected in the first trimester of pregnancy. METHODS: Our observational retrospective study enrolled women with positive anti-Toxoplasma IgG and IgM, and low/intermediate AI in the first trimester of gestation seen at two reference centres in northern Italy between 2006 and 2015. All women received spiramycin. When requested by women, a sample of fluid obtained through amniocentesis was tested with a commercial real-time PCR. CT was defined by positive PCR result confirmed on aborted materials or by newborn follow up. RESULTS: Overall, 778 first-trimester pregnant women were included; AI was low in 532/778 (68%) and intermediate in 246/778 (32%). Amniocenteses were performed in 528/778 (67.9%), with no fetal loss. In all, 19/778 (2.4%) miscarriages and 15/778 (1.9%) pregnancy terminations were recorded; 9/778 (1.6%) were lost to follow up. In two women, PCR on amniotic fluid was positive, but CT was confirmed in only 1/747 cases (0.13%, 95% CI 0.02%-0.75%). CONCLUSION: In our study, the risk of CT was much lower than anticipated. These data must be considered when counselling these women.


Subject(s)
Antibodies, Protozoan/blood , Antibody Affinity , Immunoglobulin G/blood , Infectious Disease Transmission, Vertical , Pregnancy Trimester, First , Toxoplasma/immunology , Toxoplasmosis, Congenital/epidemiology , Adult , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Italy , Pregnancy , Retrospective Studies , Risk Assessment , Young Adult
3.
Mycopathologia ; 182(9-10): 897-905, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28597394

ABSTRACT

The aims of this study were to evaluate the epidemiology of nosocomial candidemia in a large teaching hospital in Brescia, Italy, and the in vitro antifungal susceptibility of isolates. We analyzed 196 isolates causing fungemia in patients admitted in our hospital, between January 2009 and December 2015. Strains were identified by VITEK 2 and MALDI-TOF MS. MICs were determined by Sensititre Yeast OneTM. The resistance was defined by using the revised CLSI breakpoints/epidemiological cutoff values to assign susceptibility or wild type to systemic antifungal agents. Most infections were caused by Candida albicans (60%), Candida parapsilosis (15%), Candida glabrata (12%) and Candida tropicalis (6%). The susceptibility rate for fluconazole was 96.5%. Non-Candida species isolates exhibited full susceptibilities to echinocandins according to CLSI breakpoints. Amphotericin B demonstrated excellent activity against all Candida species. Local epidemiological and antifungal susceptibility studies are necessary in order to improve empirical treatment guidelines.


Subject(s)
Antifungal Agents/pharmacology , Candida/classification , Candida/drug effects , Candidiasis, Invasive/epidemiology , Candidiasis, Invasive/microbiology , Drug Resistance, Fungal , Adolescent , Adult , Aged , Aged, 80 and over , Amphotericin B/pharmacology , Candida/isolation & purification , Cross Infection/epidemiology , Cross Infection/microbiology , Echinocandins/pharmacology , Female , Fluconazole/pharmacology , Hospitals, Teaching , Humans , Italy/epidemiology , Male , Microbial Sensitivity Tests , Middle Aged , Mycological Typing Techniques , Retrospective Studies , Young Adult
4.
Lymphology ; 48(1): 6-14, 2015 Mar.
Article in English | MEDLINE | ID: mdl-26333209

ABSTRACT

Colorectal cancer is one of the most frequent causes of death in Western countries. Most patients develop metastasis traveling through the lymphatic system, and regional lymph node metastasis is considered a marker for dissemination, increased stage, and worse prognosis. Despite rapid advances in tumor biology, the processes that underpin lymphatic invasion and lymph node metastasis remain poorly understood. The aim of this study was to establish an easy protocol for isolation of pure tumor lymphatic endothelial cells derived from lymph nodes to study differences compared with normal endothelial cells of uninvolved tissue from the same patients. Cells were isolated with very high purity via magnetic cell sorting and express the specific lymphatic markers Prox-1 and Lyve-1. They show differences in expression of adhesion molecules, chemokines, and growth factor secretion, and capability to form capillaries when seeded on basal membrane, thereby, revealing important differences between the two cell type. These cultures may provide a promising platform for the comparative analysis of both cell types at the molecular and biological level and to optimize treatment strategies.


Subject(s)
Colorectal Neoplasms/pathology , Endothelial Cells/physiology , Cell Movement , Cell Separation , Cells, Cultured , Chemokine CCL2/analysis , Cytokines/metabolism , Humans , Intercellular Adhesion Molecule-1/analysis , Lymphangiogenesis , Lymphatic Metastasis , Phenotype
6.
Antimicrob Agents Chemother ; 59(4): 2466-9, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25666148

ABSTRACT

Of 901 group B streptococcus strains analyzed, 13 (1.4%) were resistant to levofloxacin (MICs of >32 µg/ml for seven isolates, 2 µg/ml for four isolates, and 1.5 µg/ml for four isolates). Mutations in the quinolone resistance-determining regions (QRDRs) of gyrase and topoisomerase IV were identified. A double mutation involving the Ser-81 change to Leu for gyrA and the Ser-79 change to Phe or to Tyr for parC was linked to a high level of fluoroquinolone resistance. In addition, two other mutational positions in parC were observed, resulting in an Asp-83-to-Tyr substitution and an Asp-83-to-Asn substitution. Different mutations were also observed in gyrB, with unknown significance. Most levofloxacin-resistant GBS strains were of serotype Ib and belonged to sequence type 19 (ST19) and clonal complex 19 (CC-19). Most of them exhibited the epsilon gene.


Subject(s)
Anti-Bacterial Agents/pharmacology , Levofloxacin/pharmacology , Streptococcus agalactiae/drug effects , DNA Gyrase/genetics , DNA Topoisomerase IV/genetics , DNA Topoisomerases, Type I/genetics , Drug Resistance, Bacterial/genetics , Italy , Microbial Sensitivity Tests , Mutation , Streptococcus agalactiae/genetics
7.
J Thromb Haemost ; 12(9): 1480-7, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25040440

ABSTRACT

BACKGROUND: Although warfarin and other vitamin K antagonists (VKAs) are the most widely used oral anticoagulants for the prevention and treatment of thromboembolic events, a number of factors hamper their manageability, the most important being the inter-individual variability of the therapeutic dose requirement. Following the discovery of the influence of CYP2C9 and VKORC1 polymorphisms on VKA dose requirements, there has been interest in genotype-guided VKA dosing in order to reduce the risk of over-anticoagulation at the time of therapy initiation and hence the risk of bleeding, particularly prominent during the early days of treatment. To assess the impact on clinical outcomes of pharmacogenetic testing for initial VKA dosing, we have performed a systematic review and meta-analysis of the literature. METHODS: MEDLINE, EMBASE and Cochrane databases were searched up to March 2014. Only randomized controlled trials comparing genotype-guided vs. clinically-guided warfarin dosing were included. RESULTS: Nine trials including 2812 patients met the inclusion criteria and were pooled for meta-analytical evaluation. Risk of bias, assessed according to the Cochrane methodology, showed a low risk for the majority of domains analyzed in the included trials. A statistically significant reduction in the risk ratio (RR) for developing major bleeding events was observed in the pharmacogenetic-guided group compared with the control group (RR = 0.47; 95% CI, 0.23-0.96; P = 0.040). CONCLUSIONS: The results of this meta-analysis show that genotype-guided initial VKA dosing is able to reduce serious bleeding events by approximately 50% compared with clinically-guided dosing approaches.


Subject(s)
Anticoagulants/adverse effects , Hemorrhage/complications , Pharmacogenetics/methods , Vitamin K/antagonists & inhibitors , Adult , Aged , Blood Coagulation , Cytochrome P-450 CYP2C9/genetics , Female , Genotype , Hemorrhage/chemically induced , Humans , International Normalized Ratio , Male , Middle Aged , Prospective Studies , Randomized Controlled Trials as Topic , Reproducibility of Results , Thromboembolism/drug therapy , Treatment Outcome , Vitamin K Epoxide Reductases/genetics , Warfarin/adverse effects
8.
Thromb Haemost ; 112(3): 511-21, 2014 Sep 02.
Article in English | MEDLINE | ID: mdl-24899092

ABSTRACT

Bleeding is a common and feared complication of oral anticoagulant therapy. Several prediction models have been recently developed, but there is a lack of evidence in patients with venous thromboembolism (VTE). The aim of this study was to validate currently available bleeding risk scores during long-term oral anticoagulation for VTE. We retrospectively included adult patients on vitamin K antagonists for VTE secondary prevention, followed by five Italian Anticoagulation Clinics (Cuneo, Livorno, Mantova, Napoli, Varese), between January 2010 and August 2012. All bleeding events were classified as major bleeding (MB) or clinically-relevant-non-major-bleeding (CRNMB). A total of 681 patients were included (median age 63 years; 52.0% female). During a mean follow-up of 8.82 (± 3.59) months, 50 bleeding events occurred (13 MB and 37 CRNMB), for an overall bleeding incidence of 9.99/100 patient-years. The rate of bleeding was higher in the first three months of treatment (15.86/100 patient-years) than afterwards (7.13/100 patient-years). The HAS-BLED showed the best predictive value for bleeding complications during the first three months of treatment (area under the curve [AUC] 0.68, 95% confidence interval [CI] 0.59-0.78), while only the ACCP score showed a modest predictive value after the initial three months (AUC 0.61, 95%CI 0.51-0.72). These two scores had also the highest sensitivity and the highest negative predictive value. None of the scores predicted MB better than chance. Currently available bleeding risk scores had only a modest predictive value for patients with VTE. Future studies should aim at the creation of a new prediction rule, in order to better define the risk of bleeding of VTE patients.


Subject(s)
Anticoagulants/adverse effects , Hemorrhage/epidemiology , Research Design/statistics & numerical data , Venous Thromboembolism/diagnosis , Aged , Anticoagulants/administration & dosage , Cohort Studies , Female , Follow-Up Studies , Hemorrhage/chemically induced , Hemorrhage/prevention & control , Humans , Italy , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies , Skin Tests , Time Factors , Venous Thromboembolism/complications , Venous Thromboembolism/drug therapy , Vitamin K/antagonists & inhibitors
9.
J Infect Public Health ; 6(3): 179-85, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23668462

ABSTRACT

The severity and extent of disease caused by multidrug-resistant organisms (MDROs) varies by the population(s) affected and the institution(s) at which these organisms are found; therefore, preventing and controlling MDROs are extremely important. A retrospective study of patients who were infected with Acinetobacter baumannii or Pseudomonas aeruginosa was performed at the Spedali Civili Hospital in Brescia, Italy, from 2007 to 2010. A total of 167 (0.52%) A. baumannii isolates and 2797 P. aeruginosa (8.7%) isolates were identified among 31,850 isolates. Amikacin and colistin were the most active agents against A. baumannii strains. Multidrug resistance (MDR) was observed in 57 isolates (54%). Most MDR isolates (42 out of 57, 73%) were resistant to four classes of antibiotics. P. aeruginosa was recovered more frequently from the respiratory tract, followed by the skin/soft tissue, urine and blood. Colistin, amikacin and piperacillin/tazobactam were active against 100%, 86% and 75% of P. aeruginosa isolates, respectively. A total of 20% (n=316) of P. aeruginosa isolates were MDR. In summary, A. baumannii was more rare than P. aeruginosa but was more commonly MDR. Epidemiological data will help to implement better infection control strategies, and developing a local antibiogram database will improve the knowledge of antimicrobial resistance patterns in our region.


Subject(s)
Acinetobacter Infections/epidemiology , Cross Infection/epidemiology , Drug Resistance, Multiple, Bacterial , Pseudomonas Infections/epidemiology , Acinetobacter Infections/microbiology , Acinetobacter baumannii/isolation & purification , Anti-Infective Agents/therapeutic use , Cross Infection/microbiology , Humans , Italy/epidemiology , Microbial Sensitivity Tests , Prevalence , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/isolation & purification , Retrospective Studies
11.
Infection ; 41(4): 827-31, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23575516

ABSTRACT

BACKGROUND: Interferon-gamma release assays (IGRAs) have high specificity and sensitivity for the diagnosis of tuberculosis (TB) infection. However, their role as a screening tool in children with immunodeficiency disorders is still unclear. In the present study, we performed a contact investigation using serial IGRAs on children with immunodeficiency conditions exposed to a contagious TB patient. METHODS: Children who were exposed to a contagious TB case underwent serial QuantiFERON(®) TB Gold In-Tube (QFT-GIT) and T-SPOT(®).TB (T-SPOT) testing. RESULTS: Eighteen children were tested. At the first testing, only two children (11 %) were positive to T-SPOT. Indeterminate results were more frequent with QFT-GIT (35 %) than with T-SPOT (12 %). In the multivariable analysis, a statistically significant association of lymphocyte count <500 cells/mm(3) (p < 0.00005) and low age (p = 0.03) with indeterminate results for the QFT-GIT test but not for T-SPOT (p = 0.10 and p = 0.88, respectively) was found. At the end of October 2012, 15 of the 18 children were alive and none developed active TB disease. CONCLUSION: T-SPOT provided more determinate results and was less influenced by low age and lymphocytopenia than QFT-GIT in this population of immunodeficient children. These findings suggest that T-SPOT is a more accurate test for the identification of TB infection in young children with lymphocytopenia and should be preferred to QFT-GIT under such specific conditions.


Subject(s)
Contact Tracing/methods , Interferon-gamma Release Tests/methods , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/transmission , Adolescent , Child , Child, Preschool , Cross Infection/diagnosis , Cross Infection/transmission , Female , Hematologic Neoplasms/complications , Humans , Infant , Male , Mass Screening/methods , Young Adult
12.
Haemophilia ; 19(3): e126-32, 2013 May.
Article in English | MEDLINE | ID: mdl-23387825

ABSTRACT

The low-density lipoprotein receptor-related protein 1 (LRP1) is an ubiquitously expressed endocytic receptor that, among its several functions, is involved in the catabolism of coagulation factor VIII (FVIII) and in the regulation of its plasma concentrations. Although LRP1/CD91 polymorphisms have been associated with increased FVIII levels and a consequent thrombotic risk, no data are available on LRP1/CD91 expression in patients with inherited FVIII deficiency. With the aim of elucidating this issue, 45 consecutive patients with haemophilia A (HA) (18 severe, 5 moderate and 22 mild HA) were enrolled in this cross-sectional, single-centre survey. The LRP1/CD91 mean fluorescence intensity (MFI) in monocytes from HA patients was significantly higher than that detected in 90 healthy blood donors (105 vs. 67, P < 0.001). This over-expression was independent of hepatitis C virus infection status and varied according to the severity of the haemophilia, being higher in patients with more severe FVIII deficiency. In conclusion, our study documents for the first time that LRP1/CD91 is over-expressed on monocytes from HA patients, with the intensity of expression varying according to the severity of the FVIII deficiency. Further studies are needed to assess the clinical implications of these findings.


Subject(s)
Hemophilia A/metabolism , Low Density Lipoprotein Receptor-Related Protein-1/metabolism , Monocytes/metabolism , Adult , Aged , Cross-Sectional Studies , Hemophilia A/complications , Hemophilia A/pathology , Hepatitis C/complications , Humans , Male , Middle Aged , Monocytes/immunology , Severity of Illness Index , Up-Regulation
14.
Cell Death Dis ; 1: e61, 2010 Aug 05.
Article in English | MEDLINE | ID: mdl-21364666

ABSTRACT

Dysferlin deficiency leads to a peculiar form of muscular dystrophy due to a defect in sarcolemma repair and currently lacks a therapy. We developed a cell therapy protocol with wild-type adult murine mesoangioblasts. These cells differentiate with high efficiency into skeletal muscle in vitro but differ from satellite cells because they do not express Pax7. After intramuscular or intra-arterial administration to SCID/BlAJ mice, a novel model of dysferlinopathy, wild-type mesoangioblasts efficiently colonized dystrophic muscles and partially restored dysferlin expression. Nevertheless, functional assays performed on isolated single fibers from transplanted muscles showed a normal repairing ability of the membrane after laser-induced lesions; this result, which reflects gene correction of an enzymatic rather than a structural deficit, suggests that this myopathy may be easier to treat with cell or gene therapy than other forms of muscular dystrophies.


Subject(s)
Aging/pathology , Blood Vessels/metabolism , Blood Vessels/pathology , Membrane Proteins/metabolism , Muscular Dystrophies, Limb-Girdle/physiopathology , Recovery of Function/physiology , Animals , Biological Assay , Blood Vessels/transplantation , Disease Models, Animal , Dysferlin , Inflammation/pathology , Mice , Mice, Inbred C57BL , Mice, SCID , Muscle, Skeletal/pathology , Muscular Dystrophies, Limb-Girdle/metabolism , Muscular Dystrophies, Limb-Girdle/pathology
15.
Neurol Sci ; 27(4): 257-60, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16998729

ABSTRACT

Human T-cell lymphotropic virus type I (HTLV-I) is a human retrovirus and the aetiological agent of a progressive neurological disease called tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM), as confirmed by evidence accumulated in HTLV-I seroprevalence studies. TSP/HAM is rarely diagnosed in Italy, given the low prevalence of HTLV-I in the population. TSP/HAM begins insidiously in the fourth decade, mainly with spastic paraparesis of the lower extremities and positive Babinski reflex, as well as interfering with bowel and bladder functions. In this study we report the clinical, virological and haemato chemical data of a 54-year-old woman, born in the Ivory Cost, with symptoms suggestive of TSP. The presence of HTLV-I infection was demonstrated by the detection of antibodies in serum and in cerebrospinal fluid by immunoenzymatic assay and Western blot analysis. In addition, viral isolation was carried out in peripheral blood cells, and the presence of HTLV-I proviral DNA was confirmed by polymerase chain reaction/Southern blot and sequencing analysis. According to our results, HTLV-I testing might be useful when TSP/HAM is suspected.


Subject(s)
Human T-lymphotropic virus 1/isolation & purification , Paraparesis, Tropical Spastic/diagnosis , Paraparesis, Tropical Spastic/virology , Blotting, Southern/methods , Female , Human T-lymphotropic virus 1/genetics , Humans , Magnetic Resonance Imaging/methods , Middle Aged , Paraparesis, Tropical Spastic/pathology , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods
16.
Metabolism ; 53(5): 563-70, 2004 May.
Article in English | MEDLINE | ID: mdl-15131758

ABSTRACT

Sex steroids play an important role in modulating pulsatile growth hormone (GH) release, acting at both hypothalamic and pituitary level in both humans and experimental animals. Selective estrogen receptor modulators (SERMs) act as either estrogen receptor agonists or antagonists in a tissue-selective manner. In postmenopausal women, serum GH levels correlate positively with endogenous estradiol levels and insulin-like grwoth factor-I (IGF-I) is positively related to bone mineral density (BMD) at the spine and hip. The aim of the present study was to evaluate, for the first time, the direct effect of LY117018, an analog of raloxifene, on GH secretion from both human and rodent pituitary cells in vitro. Our results demonstrated that pharmacological concentrations of the raloxifene analog LY117018 can stimulate GH secretion through a direct action on the pituitary. LY117018 also showed an estrogen-like activity, inducing the proliferation of rat pituitary GH-secreting adenomatous cells (GH1).


Subject(s)
Growth Hormone/metabolism , Pyrrolidines/pharmacology , Selective Estrogen Receptor Modulators/pharmacology , Thiophenes/pharmacology , Adenoma/metabolism , Adult , Aged , Animals , Cell Division/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Estradiol/pharmacology , Female , Growth Hormone-Releasing Hormone/pharmacology , Humans , Male , Middle Aged , Pituitary Gland/cytology , Pyrrolidines/chemistry , Raloxifene Hydrochloride/chemistry , Rats , Rats, Sprague-Dawley , Secretory Rate/drug effects , Tamoxifen/pharmacology , Thiophenes/chemistry
17.
J Endocrinol Invest ; 26(4): 359-63, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12841545

ABSTRACT

Somatostatin receptors are highly expressed in almost all meningiomas but in this setting their functional role is not clear. A 59-yr-old woman had been treated with octreotide after an unsuccessful operation for a GH-secreting pituitary adenoma. After 8 yr of treatment, a nuclear magnetic resonance (NMR) scan disclosed a 3 cm meningioma of the tentorium. Mean GH was 2.2 ng/ml and IGF-I 325 ng/ml. Meningioma was resected and tissue was digested to obtain tumor cell suspension. Aim of the study was to measure epidermal growth factor (EGF)-induced proliferation of cultured meningioma cells in the presence of either somatostatin or octreotide. Cells were grown to semiconfluency in Dolbecco's modified eagle medium (D-MEM) supplemented with 10% fetal calf serum (FCS). After 48 h in D-MEM without serum, the medium was replaced by fresh medium plus recombinant EGF (10 ng/ml) and somatostatin or octreotide were added in the final concentrations of 1, 10 and 100 nM. 20 h later 1 microcgCi of 3H-thymidine was added to each well. After 4 h, incorporated radioactivity was measured. While octreotide did not influence significantly cell growth at the three dose tested, somatostatin increased thymidine incorporation dose-dependently (peak 100 nM: 150% +/- 27% vs medium plus EGF, p<0.05). Octreotide effectively suppressed GH secretion in our acromegalic patient but is unlikely that its long-term use could have stimulated the growth of meningioma since it did not significantly influence the in vitro proliferation of the meningioma cells. These results suggest that somatostatin-mediated proliferative effect on meningioma cells is not mediated by the subtype 2 of the somatostatin receptor.


Subject(s)
Acromegaly/complications , Meningeal Neoplasms/etiology , Meningioma/etiology , Octreotide/adverse effects , Receptors, Somatostatin/drug effects , Acromegaly/drug therapy , Cell Division/drug effects , Epidermal Growth Factor/pharmacology , Female , Humans , Magnetic Resonance Imaging , Meningeal Neoplasms/pathology , Meningioma/pathology , Middle Aged , Octreotide/therapeutic use , Somatostatin/adverse effects , Somatostatin/analogs & derivatives , Somatostatin/therapeutic use , Tumor Cells, Cultured
18.
Scand J Immunol ; 55(3): 284-92, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11940235

ABSTRACT

The mouse monoclonal antibody (MoAb) IGMB17 (muIGMB17) is a high-affinity antibody- neutralizing human interferon (IFN)-gamma and, accordingly, is a potential therapeutic agent for patients suffering from various diseases in which the cytokine is abnormally expressed. The clinical usefulness of mouse antibodies is limited, however, owing to their immunogenicity in humans. MuIGMB17 antibody was partially humanized by engrafting a small portion of mouse light chain (LC) in a human framework and by engineering its heavy chain (HC) in a chimeric version. The engineered IGMB17 (huIGMB17) was able to replicate a range of functional properties of the original muIGMB17, namely, specific binding to IFN-gamma, inhibition of histocompatibility complex (HLA-DR) expression in response to IFN-gamma induction, reversion of IFN-gamma antiproliferative activity on sensitive cell lines. We have hypothesized that as huIGMB17 was able to block IFN-gamma binding to its receptor as well as its murine counterpart, huIGMB17 could neutralize all cytokine activity, also in vivo. Indeed huIGMB17 was capable of interfering with delayed-type hypersensitivity reaction in humans, thus demonstrating its effectiveness in neutralizing IFN-gamma-mediated reactions in vivo.


Subject(s)
Antibodies, Monoclonal/pharmacology , Cytokines/antagonists & inhibitors , Interferon-gamma/antagonists & inhibitors , Interferon-gamma/immunology , Animals , Antibodies, Monoclonal/genetics , Base Sequence , Cell Line , Cloning, Molecular , DNA, Recombinant/genetics , Humans , Immunotherapy , In Vitro Techniques , Mice , Molecular Sequence Data , Neutralization Tests , Protein Engineering , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , Tuberculin/immunology
19.
Neuroendocrinology ; 73(5): 344-51, 2001 May.
Article in English | MEDLINE | ID: mdl-11399907

ABSTRACT

Somatostatin (SRIH), a cyclic tetradecapeptide hormone originally isolated from mammalian hypothalamus, is a potent suppressor of pituitary growth hormone (GH) secretion. SRIH acts through a family of G-protein-coupled membrane receptors containing seven transmembrane domains. Five genes encoding distinct SRIH receptor (SSTR) subtypes have so far been cloned in human and other species and termed SSTR1-5. In human somatotrophe pituitary adenomas GH secretion is controlled by both SSTR2 and SSTR5. However, in clinical practice only somatostatin analogs selective for SSTR2 (octreotide and lanreotide) are available. This may explain why clinical and in vitro responses to these analogs in acromegaly are only partial. In this study, we investigated the inhibitory effect of two new SRIH analogs with high selectivity for SSTR2 (NC-4-28B) and SSTR5 (BIM-23268) and compared it to that of native somatostatin (SRIH-14) on a large number of GH-secreting adenomas obtained by transphenoidal neurosurgery. Tissues from 16 adenomas were enzymatically dispersed and plated in 24-well dishes at 50,000 cells/well. After 3 days, groups of three wells were incubated for 4 h with medium alone, SRIH-14 or analogs NC-4-28B or BIM-23268, at the concentrations of 0.01, 0.1 and 1 microM. Our results show that 9 out of 16 adenomas were responsive (GH suppression: 20-40% vs. control, p < 0.05) to SRIH. In this group only 4 adenomas showed similar responses to both selective analogs, with 2 nonresponders (expression of other SRIH receptor subtypes) and 2 responders (concomitant expression of SSTR2 and SSTR5) to both analogs. GH release was selectively inhibited by NC-4-28B in 3 adenomas and by BIM-23268 in the remaining 2 adenomas, suggesting predominant expression of SSTR2 and SSTR5, respectively. SRIH failed to inhibit GH release in 7 adenomas (43%). Interestingly, in that group a better inhibitory effect was obtained with BIM-23268 (5 out of 7 adenomas) than with NC-4-28B, suggesting expression of a few SSTR5 receptors only, or of both SSTR2 and SSTR5, respectively. We conclude that the availability of somatostatin analogs selective for SSTR5 will enhance the treatment potency and spectrum in acromegaly.


Subject(s)
Adenoma/metabolism , Human Growth Hormone/metabolism , Pituitary Neoplasms/metabolism , Receptors, Somatostatin/physiology , Somatostatin/analogs & derivatives , Somatostatin/pharmacology , Adult , Aged , Dose-Response Relationship, Drug , Female , Human Growth Hormone/antagonists & inhibitors , Humans , Male , Middle Aged , Receptors, Somatostatin/drug effects
20.
Regul Pept ; 70(1): 49-54, 1997 May 14.
Article in English | MEDLINE | ID: mdl-9250581

ABSTRACT

Previous studies demonstrated that GHRP-6 has modest GH-releasing activity in primary pituitary cell monolayer cultures. However, the effects of this peptide have always been tested on cells very sensitive to GHRH. We have previously reported that GHRH is unable to stimulate GH secretion in the GH1 rat tumor cell line. The aim of the study was to assess for the first time the effect on GH secretion of the GHRP-6 analog, hexarelin, in the GH1 cells; moreover, we investigated the potential involvement of GHRH in the effects of hexarelin in the GH1 rat cell line. The GHRP-6 analog hexarelin (0.01-1 microM) significantly stimulated GH release in both normal and GH1 rat cells. The greatest GH-releasing effect of hexarelin was observed with the 1 microM dose both in GH1 (155+/-25% vs. control wells) and in normal rat pituitary cells (185+/-23% vs. control wells). GHRH significantly stimulated GH secretion in normal rat somatotrophs (3-fold increase). In this latter cell model, GHRH and hexarelin were demonstrated to have additive stimulatory effects on GH secretion. Conversely, GHRH did not affect hexarelin-stimulated GH release in GH1 cells at any of the doses used. Finally, 8Br-cAMP significantly stimulated GH secretion in both normal rat and GH1 cells. These results provide in vitro evidence that non-GHRH-mediated pathways for GHRP action exist. Moreover, the observation that cells not sensitive to GHRH can be significantly stimulated by hexarelin strongly suggests that GHRPs and GHRH have two distinct sites and modes of action at the pituitary level.


Subject(s)
Growth Hormone-Releasing Hormone/pharmacology , Growth Hormone/metabolism , Growth Substances/pharmacology , Oligopeptides/pharmacology , Pituitary Gland/drug effects , 8-Bromo Cyclic Adenosine Monophosphate/pharmacology , Animals , Dose-Response Relationship, Drug , Growth Hormone-Releasing Hormone/metabolism , Male , Pituitary Gland/metabolism , Pituitary Neoplasms/metabolism , Rats , Rats, Sprague-Dawley , Tumor Cells, Cultured
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