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Biomedical subjects

L Morelli

Publications and source records attributed to L Morelli.

At least 19 recordsLinked to original sources
PubMed1992

Heterogeneity of natural killer cell subsets in NK-1.1+ and NK-1.1- inbred mouse strains and their progeny.

The 4LO3311 monoclonal antibody, a new NK-specific reagent recently produced in our laboratory, reacts with spleen cells of 11 mouse strains, most of which do not express the NK-1.1 alloantigen recognized by the PK136 mAb. Among positive strains, the susceptibility of spleen cells to the complement-dependent NK-inhibiting activity of the 4LO3311 mAb was variable but independent of the initial NK cell activity level of cells tested. This property was furthermore not modified after poly(I:C) stimulation. The susceptibility of spleen cells to the in vitro 4LO3311 mAb plus complement treatment is however influenced by the absolute number of 4LO3311+ cells as well as by the density of the corresponding alloantigen at the cell surface. Moreover, it was established that the strain-related variations observed also depended upon the relative size of the 4LO3311 cell subset within the lytic NK cell population. Indeed, when C3H (NK-1.1-4LO3311+) mice were inoculated with the 4LO3311 mAb, the lytic activity of their spleen cells was almost unaltered but 4LO3311-reactive cells were no longer detected in the spleen of treated animals and remaining NK cells were totally resistant to the in vitro 4LO3311 mAb plus complement treatment. These findings indicate that the 4LO3311 mAb identifies a subset rather than all NK cells, even in a NK-1.1- strain. Since a NK-1.1-unreactive cell subset was identified in NZB (NK-1.1+4LO3311-) mice inoculated with the PK136 mAb, the NK-1.1+ cell population is not necessarily responsible for all the splenic NK cell activity in all NK-1.1+ strains. In B6C3F1 hybrid mice, a relatively large subset of NK-1.1-4LO3311- cells was found in addition to those expressing the NK-1.1, the 4LO3311 alloantigen, or both. According to these results, NK cell heterogeneity should thus be taken as an evolving concept whose resolution appears more and more complex with the identification of new NK-specific reagents.

Animals↗
PubMed1992

Novel surface molecules involved in human NK cell activation and triggering of the lytic machinery.

Three new monoclonal antibodies (MAbs) termed 7A6, PP35 and A6/143 were isolated after mouse immunization with CD3- CD16+ NK clones. The screening procedure was based on the ability of MAbs to trigger cytolytic activity of the immunizing clones in a re-directed killing assay against the P815 murine mastocytoma cell line. The 7A6 MAb reacts with 58 kDa surface molecules that appear to belong to the same molecular family defined by the previously described NK-sub-set-specific GL183 and EB6 MAbs. However, unlike from these MAbs, the 7A6 MAb reacted with (and activated) all CD3- NK lymphocytes, independent of their sub-set assignment (based on the expression or lack of expression of EB6, GL183 and CD16). The PP35 MAb reacted with a 70 kDa surface molecule expressed on all CD3- NK cells, as well as on TCR gamma/delta + cells and on a small sub-set of TCR alpha/beta + CD8+ lymphocytes. The PP35 MAb induced activation of essentially all NK cells, although clonal analysis revealed quantitative differences in the magnitude of the cytolytic responses elicited in different clones. Finally, the A6/143 MAb reacted with a molecule of 115 kDa expressed by all human PBL. Similarly to 7A6 and PP35 MAbs, the A6/143 MAb activated all sub-sets of cloned NK cells.

Animals↗
PubMed1992

[Recent experience in the short-term etizolam treatment of irritable colon syndrome].

Twenty-two subjects (8 males, 14 females, mean age 36 years, range 21-57) with symptoms of diffuse pain or fullness in a lower abdominal quadrant, without repercussions on general health but with chronic anxiety of which the subjects complained or which emerged during confidential conversation with the physicians, were enrolled in our outpatient department for liver and gastroenterologic pathology at the Institute of Internal Medicine and Metabolic Disorders, II Faculty of Medicine, Naples University. After an average 30-day wash-out period, patients were treated with etizolam, a new psychoactive drug for somatized anxiety. Mean dosage and duration of treatment were 1 tablet twice daily for 25 days. Painful symptoms disappeared in 16.3% of patients, decreased in 38.3% and remained stationary in 22.7% and became worse in 22.7%. Number of bowel motions decreased in 14 patients (63.6%, from an average of 2.04 to 1.56). It can therefore be concluded that etizolam treatment was effective in subjects with colon disorders accompanied by chronic anxiety syndrome or that became acute as result of stressful socio-economic or affective situations or personal disappointment.

Adult↗
PubMed1991

In vitro proliferation and cloning of CD3- CD16+ cells from human thymocyte precursors.

Purified CD3-4- thymocytes were obtained by depletion of CD3+ and CD4+ cells from fresh thymocyte suspensions. 5-15% of these cells were found to express CD16 antigen, while other natural killer (NK) cell markers were virtually absent. Double fluorescence analysis revealed that 20-40% of thymic CD16+ cells coexpressed CD1, while approximately half were cyCD3+. When cultured in the presence of peripheral blood lymphocytes and H9 leukemia cell line as a source of irradiated feeder cells and interleukin 2 (IL-2), CD3-4- thymocytes underwent extensive proliferation. In addition, after 1-2 wk of culture, 30-50% of these cells were found to express CD16 surface antigen. Cloning under limiting dilution conditions of either CD3-4- or CD3-4-16- thymocytes in the presence of irradiated H9 cells resulted in large proportions (approximately 50%) of CD16+ clones. On the basis of the expression of surface CD16 and/or cyCD3 antigen, clones could be grouped in the following subsets: CD16+ cyCD3+; CD16+ cyCD3-; CD16- cyCD3+; and CD16- cyCD3-. All clones expressed CD56 surface antigen, displayed a strong cytolytic activity against NK sensitive (K562) and NK-resistant (M14) target cells, and produced IFN-gamma and tumor necrosis factor, but not IL-2. Similar to peripheral NK cells, thymic CD16+ cells expressed transcripts for CD16 and for CD3 epsilon (Biassoni, R., S. Ferrini, I. Prigione, A. Moretta, and E.O. Long, 1988. J. Immunol. 140:1685.) and zeta chains (Anderson, P., M. Caligiuri, J. Ritz, and S.F. Schlossman. 1989. Nature [Lond.]. 341:159). Therefore, it appears that cells that are phenotypically and functionally similar to CD3- CD16+ NK cells may arise from immature thymocytes.

Antigens, CD↗
PubMed1991

Identification of murine natural killer cell subsets with monoclonal antibodies derived from 129 anti-C57BL/6 immune spleen cells.

Two hybridomas producing monoclonal antibodies reactive with natural killer cells were selected after fusion of 129 anti-C57BL/6 immune spleen cells with P3X63-Ag8.653 myeloma cells. Treatment of normal or stimulated cells with the 4LO3311 or the 4LO439 mAb and rabbit complement inhibited natural killer and antibody-dependent cellular cytotoxicities, whereas cell lysis mediated by natural cytotoxic cells, cytotoxic T lymphocytes, or activated macrophages was unaffected. Lymphokine-activated killer activity was reduced after complement-mediated treatment of interleukin-2-stimulated spleen cells with the 4LO3311 mAb but not after treatment with the 4LO439 mAb. Similar treatment of spleen cells with either mAb had no effect on the mitogen-induced proliferation of T and B lymphocytes and did not alter the frequency of antibody plaque-forming cells in immune spleen cell suspensions. The 4LO3311 and 4LO439 mAbs thus appear to be specific for NK cells and their progeny. Flow cytometry analysis confirmed that 4LO3311+ and 4LO439+ cells are phenotypically identical to NK-1.1+ cells. The epitope recognized by the 4LO3311 mAb has the same strain distribution as the NK-2.1 alloantigen previously detected with NZB anti-BALB/c antiserum, whereas the 4LO439 mAb appears to identify a new NK cell marker exclusively expressed in mice of C57BL lineage. The relationship of the molecules detected with either the 4LO3311 or the 4LO439 mAb to polymorphic antigens of the Ly series is discussed.

Animals↗
PubMed1991

Effect of recombinant human tumor necrosis factor on A2774 human ovarian cancer cell line: potentiation of mitoxantrone cytotoxicity.

Recombinant human tumor necrosis factor (rHuTNF) is a macrophage-secretory protein with antitumor activity. In vivo and in vitro cytotoxicity studies have been carried out to test the effectiveness of rHuTNF alone or in combination with chemotherapeutic agents. We have evaluated the direct cytotoxic effect of rHuTNF on a human epithelial ovarian cancer cell line in vitro (A2774), alone, or in combination with mitoxantrone (Mit), a topoisomerase II (Topo II) targeted drug. Our results not only suggest that rHuTNF is directly cytotoxic, but also that it is able to induce a very strong potentiation of Mit cytotoxicity.

Dose-Response Relationship, Drug↗
PubMed1991

Human brucellosis: immunoblotting analysis of three Brucella abortus antigenic fractions allows the detection of components of diagnostic importance.

Results indicating that analysis of the immune humoral response of brucellosis patients by immunoblotting provides useful information for the characterization of antigenic fractions of possible diagnostic importance in human brucellosis are presented. Sera of 90 patients were obtained: 23 suffering from chronic brucellosis, 20 from acute brucellosis and 47 belonging to the group of serologically positive individuals (SPI) without clinical evidence of active infection at the time of examination, and 35 healthy volunteers. They were tested against three antigenic fractions: cytoplasmic (CYT), outer membrane (OM) and inner membrane (IM). These fractions, which include virtually all the bacterial protein components, were prepared from Brucella abortus 1119/3 strain by detergent solubilization, enzymatic digestion and ultracentrifugation. Results obtained with these fractions showed the existence of antigens that permit the detection of brucellosis patients and their differentiation from SPI patients, with very high sensitivity.

Antigens, Bacterial↗
PubMed1990

Experimental pathogenicity and acid proteinase secretion of vaginal isolates of Candida parapsilosis.

Isolates of Candida parapsilosis from women with or without candidal vaginitis were compared for their ability to produce secretory aspartate (acid) proteinase and their virulence for normal or cyclophosphamide-immunodepressed mice. Although all isolates were strongly proteolytic in vitro, only those from candidosis-affected subjects were appreciably pathogenic for neutropenic mice. In these animals, organ invasion was monitored after challenge with representative isolates of each category. The number of yeast cells in the kidneys of animals infected with an isolate from a subject without candidal vaginitis was approximately one order of magnitude less than that in mice infected with either one of two isolates from patients with candidal vaginitis. Mice infected with either category of C. parapsilosis isolates developed antibodies against a mannoprotein-rich extract of the cell wall, and these antibodies did not cross-react with a chemically similar preparation from Candida albicans. However, only those animals which had been challenged with one of the isolates from a candidosis subject produced a low level of antibodies, detectable by ELISA, against an acid proteinase of C. parapsilosis. These antibodies cross-reacted with a highly purified enzyme preparation of C. albicans. The data demonstrate differences in the potential virulence of different isolates of C. parapsilosis and suggest that the ability to express the acid proteinase in vivo may be related to differences in pathogenicity.

Adult↗
PubMed1990

[Uridine diphosphate glucose (UDPG) in the treatment of hepatic disease from chronic alcohol abuse].

Fatty liver can be determined by chronic abuse of alcohol, by means of direct action of the same on the level of membrane's proteins. The UDPG restores the levels of a membrane's component, the phosphoribosylpyrophosphate (PRPP), which normally results reduced in cellular cultures of rat's liver, after the addition of alcohol. It has been made a study on 40 patients (27 men and 13 women age medium 54 years) alcoholics for at least 1 year with a quantity of ethanol ingested less than 1 g gamma/die/kg of body weight with alternated values of serum GOT, GPT and gamma-GT and clinical aspects of a modest alcoholic hepatopathy, assigning through, at random in double blind, two groups of treatment: the first one with UDPG (400 mg/im/die for 30 days) the second one with placebo. It has been considered like variable of therapeutic effect the difference between basal value and the result at the end of treatment of these serum enzymes, it has been applied the Student's t test for the evaluation of the difference between treatments. It has been shown in the groups of patients analyzed with UDPG (not the group of placebo) reduction extremely significant for the gamma-GT (p = 0.00032) and GOT (p = 0.0138). In 5 treated cases, after an hepatic ultrasound imaging of comparison, at the end of the treatment, it has been demonstrated an apparent improvement of thickening of the echos; only 3/40 of the patients have certainly stopped to ingest alcoholic drinks.

Female↗
PubMed1990

[Oral contraceptive and hepatic effects].

The general use of synthetic estrogens like DC pointed out that near many skilled collateral effects, some others that are showing with a decrease of bile excretion (cholestasis), reversible with their administration interruption; with hepatic cells adenoma that are potentially premalignant and can transform into hepatocellular carcinoma; with vascular complications such as (most frequently in carcinomatousis) "hepatic peliosis" and "thrombosis" of suprahepatic veins (Budd-Chiari's syndrome). There is no overall increase in the incidence of gallbladder disease (cholelithiasis and cholecystitis).

Chemical and Drug Induced Liver Injury↗
PubMed1990

Effect of recombinant human TNF on human ovarian cancer cell lines.

Ovarian cancer is the second most common gynecologic malignancy. Standard therapeutic approaches to this disease, surgery followed by chemotherapy, have produced response rates of up to 80%. However, the five-year survival rate remains around 30%. Recently, Tumor Necrosis Factor (TNF) has received attention as either an alternative or an associated agent for chemotherapy of ovarian cancer. TNF is known to have direct cytotoxic and cytostatic effects on a variety of transformed cell lines "in vitro". Furthermore, TNF is known to enhance significantly the "in vitro" effects of a class of chemotherapeutic agents, specifically those targeted at DNA topoisomerase II. In this work we have investigated TNF-induced cytotoxicity in four established human epithelial ovarian cancer cell lines: A-2774; SV-626; SKOV-3 and Pa-1. TNF mediated cytotoxic activity was observed in a range of concentrations between 1 U/ml and 10-3 U/ml. A-2774 and SV-626 were the two most sensitive lines, especially when exposed to high concentrations of TNF.

Cell Survival↗
PubMed1989

Experimental rat vaginal infection with Candida parapsilosis.

The experimental vaginopathic potential of Candida parapsilosis was determined in ovariectomized rats maintained under pseudoestrus by estrogen administrations. Of the 3 strains of C. parapsilosis tested, that isolated from the vagina of a woman affected by vulvovaginal candidosis gave a prolonged and sustained experimental vaginitis, not different in extent and duration from that caused by a vaginal isolate of C. albicans from a vaginitis patient. The other two isolates of C. parapsilosis (one from the vagina of an asymptomatic subject and another from soil) were unable to infect rat vagina. Microscopic observations of PAS-stained vaginal smears from rats infected with the vaginopathic isolate of C. parapsilosis showed pronounced adherence of yeasts to exfoliated cells. In addition, this isolate of C. parapsilosis produced an elevated quantity of acid proteinase in vitro.

Animals↗
PubMed1988

In vivo transfer of pAM beta 1 from Lactobacillus reuteri to Enterococcus faecalis.

Trials were conducted to determine the in vivo transferability of plasmid-mediated antibiotic resistance between two strains of enteric Gram-positive bacteria. Germ-free mice were associated with the donor Lactobacillus reuteri DSM 20016 strain, carrying the broad host range pAM beta 1 plasmid, and with the Enterococcus faecalis JH2SS recipient strain. Analysis of faecal content of associated mice demonstrated that the in vivo transfer of this plasmid did occur and that frequencies of conjugation were affected by the presence of subtherapeutic levels of antibiotic in the diet.

Animals↗
PubMed1987

Sequence and functional analysis of a divergent promoter from a cryptic plasmid of Lactobacillus acidophilus 168 S.

We have characterized three of at least five plasmids borne by Lactobacillus acidophilus 168 S. Restriction mapping indicates extensive sequence homology between at least two of them (p1 and p3). We have cloned them in Escherichia coli, and for the smallest (p1) we present the sequence of a region with two divergently arranged promoters which probably share a symmetrical (TTTAAA)-35 box and function efficiently in E. coli cells; an open reading frame contiguous to the promoter, which codes for a 120 amino acid protein of unknown function, and is transcribed in E. coli; and a transcription termination sequence next to this open reading frame. The promoter region contains an AT cluster which is similar to that of the ori2 region of the E. coli F plasmid, and is probably involved in the control of the replication of p1.

Base Sequence↗
PubMed1987

Lactobacillus protoplast transformation.

A method for the transformation of Lactobacillus protoplasts by plasmid DNA is reported. The procedure involves polyethylene glycol treatment of protoplasts to induce DNA uptake. A transformation efficiency ranging from 5 to 1000 transformants per microgram of DNA is achieved; the efficiency of protoplast regeneration ranged from 10 to 20%.

DNA, Bacterial↗
PubMed1986

Fast and slow milk-coagulating variants of Lactobacillus helveticus HLM 1.

Slow milk-coagulating variants were isolated from Lactobacillus helveticus HLM 1, a fast strain which coagulates milk in 16 h at 42 degrees C. Variants were isolated after subculturing in reconstituted skim milk or complex broth media. Analysis of plasmid content revealed that in slow variants a 3.5-megadalton plasmid was missing.

Animals↗