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S Pastore

Publications and source records attributed to S Pastore.

At least 37 records · Page 2Linked to original sources
PubMed1994

Lymphocyte function-associated antigen-1 is required for maximum elicitation of allergic contact dermatitis.

Cell adhesion molecules (CAMs) are known to play an important role in cell-mediated immunity and inflammation. To investigate the importance of one of the CAMs, lymphocyte function-associated antigen-1 (LFA-1) in allergic contact dermatitis (ACD), a specific anti-LFA-1 monoclonal antibody was injected into the ears of mice after sensitization but prior to challenge with dinitrofluorobenzene (DNFB). BALB/c mice were sensitized on the dorsal skin with DNFB, and challenged on the ears 6 days later. The effect of the antibody on the elicitation phase of contact sensitization was determined by its intradermal injection into the pinnae of the mice at doses of 1-40 micrograms. At 24 and 48 h after challenge, ear swelling was dose-dependently suppressed by injection of LFA-1 antibody at doses of 2-40 micrograms, which are less than 10% of the systemic dose required for effective suppression of delayed-type hypersensitivity in previous studies. Maximal inhibition of ear swelling (44%) was observed after injection of 20 micrograms of anti-LFA-1 antibody. Inhibition of ear swelling was accompanied by a reduction in dermal oedema and leucocyte infiltration into the dermis. Our results suggest that LFA-1 plays a significant role in the elicitation of ACD reactions, and also that our test system is a sensitive and useful means of evaluating the blocking effect of antibody to adhesion molecules thought to be involved in the elicitation phase of ACD.

Animals↗
PubMed1994

Characterization of epidermal cytokine profiles in sensitization and elicitation phases of allergic contact dermatitis as well as irritant contact dermatitis in mouse skin.

Epidermal cytokines are known to participate in the initiation of immune and inflammatory processes in the skin. In the present study, we examined epidermal cytokine mRNA levels to elucidate the initial molecular events in the sensitization and elicitation phases of allergic contact dermatitis (ACD) as well as in irritant contact dermatitis (ICD). BALB/c mice were sensitized on the dorsal skin with 0.5% dinitrofluorobenzene (DNFB) and challenged with 0.2% DNFB on the ears 6 days later to elicit allergic contact hypersensitivity (ACDe), the elicitation phase. To examine cytokine profiles during the sensitization phase from the same anatomic area, other animals were sensitized on ear instead of dorsal skin. The sensitization phase of ACD (ACDs) was induced by painting the ears of naive mice with 0.5% DNFB. Sodium lauryl sulfate (SLS), utilized as an irritant control, was also applied to the ears of another group of mice to induce ICD. Total RNA was extracted from the epidermis of the treated ears at various time points after each treatment, reverse transcribed to cDNA, and amplified by PCR using radiolabeled cytokine-specific primers. Amplified products were sized by electrophoresis and autoradiography and semiquantitated by densitometry. Autoradiographs were normalized relative to beta-actin signals. ACDs and ACDe showed similar patterns of cytokine mRNA levels; that is, at 6 h after hapten application, interleukin (IL)-1 beta, IL-6, IL-10, and granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA levels were upregulated, and this upregulation was observed until 24 h after treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Effects of a novel topical immunomodulator, imiquimod, on keratinocyte cytokine gene expression.

A novel immunomodulator, imiquimod, has been shown to be an effective topical antiviral and antitumor agent in animal models. Imiquimod has been reported to induce interferon-alpha and other cytokines in animals and humans, but its precise role as an immunomodulator at skin sites has not been determined. We investigated its effect on cytokine gene expression in the human epidermal carcinoma cell line COLO-16 and human keratinocytes. COLO-16 cells were incubated with imiquimod (1 and 10 micrograms/ml) and human keratinocytes with 5 micrograms/ml for 6 or 24 h. Cytokine gene expression was analyzed by reverse-transcriptase PCR. In COLO-16 cells, imiquimod stimulated IL-6 mRNA levels 2.3- and 4.4-fold at 1 and 10 micrograms/ml after 6 h. IL-8 mRNA increased 4-fold at both 1 and 10 micrograms/ml. At 24 h, though IL-6 mRNA level at 1 micrograms/ml was further stimulated, enhanced expressions of IL-8 at 1 micrograms/ml and both IL-6 and IL-8 at 10 micrograms/ml were down-regulated. In human keratinocytes, 5 micrograms/ml of imiquimod stimulated IL-6 mRNA levels 1.4-fold at 6 h and 2.1-fold at 24 h, and IL-8 mRNA levels 1.7- and 2.0-fold at 6 and 24 h. IL-1 alpha mRNA levels in COLO-16 or keratinocytes were unchanged by either dose or incubation time. These results suggest that stimulation of IL-6 and IL-8 expression may be involved in the immunomodulating action of imiquimod.

Adjuvants, Immunologic↗
PubMed1993

Relationships among alterations in renal membrane sodium transport, renin and aminopeptidase M activities in genetic hypertension.

Rats of the Milan Hypertensive Strain (MHS) may be considered a useful model for understanding the genetic molecular mechanism underlying a primary form of hypertension in at least a subgroup of patients. Many differences between MHS and its normotensive control strain (MNS) were found at the organ, cellular and biochemical level. In the present investigation renal cell membrane proteins (BBMV) were analysed by two-dimensional electrophoresis and a difference between MHS and MNS was shown in a polypeptide of 32 kDa, subsequently identified as the C-terminal fragment of aminopeptidase M (APM). The activity of the enzyme was higher in MHS. Genetic relationships between this enzyme and the other biochemical cellular abnormalities of MHS, namely sodium transport in BBMV and renin activity in kidney cortex were investigated in MHS, MNS and in two inbred recombinant strains. This analysis showed that faster sodium transport, low kidney levels of renin and hypertension, but not differences in two-dimensional electrophoretic pattern and in aminopeptidase M activity, cosegregated in recombinant strains. These results are consistent with the hypothesis that the faster sodium transport can be considered a primary cellular abnormality responsible for hypertension in MHS and that the aminopeptidase difference is not involved in the cellular abnormalities.

Aminopeptidases↗
PubMed1993

Phosphatidylserine enhances the ability of epidermal Langerhans cells to induce contact hypersensitivity.

Phosphatidylserine (PS) modulates several immune functions in vitro, including T cell activation, antibody and cytokine production, and macrophage growth. In the present work we studied the effects of PS on the induction of contact hypersensitivity (CH) in mice. BALB/c mice painted with PS (9.4-75 mg/kg) and with a sensitizing dose of DNFB or oxazolone on the same skin site exhibited a dose-dependent augmentation of CH reactions to either DNFB (> 60%) or oxazolone (> 35%), respectively. Bovine brain PS-enriched phospholipid mixture, lyso-PS, and dipalmitoyl-PS also induced similar enhanced CH responses, whereas phosphatidylglycerols had no effect. Increased CH was observed only when PS was applied from 2 days before to 12 h after DNFB. Immunization of naive syngeneic mice with skin grafts that were treated with PS and DNFB also led to enhanced (> 50%) CH responses. In addition, immunization by iv injection of epidermal cell suspensions enriched for Langerhans cells (LC) or of purified LC that were treated with PS (1-100 microM, 30 min, 37 degrees C), and then modified in vitro with DNBS (1 mg/ml, 30 min, 37 degrees C) led to increased (> 30-75%) CH responses in recipient syngeneic animals. Finally, adoptive transfer of DNFB-immune lymph node cells obtained from mice that were treated with PS induced augmented CH responses in recipient animals. The results suggest that PS is capable of up-regulating the induction of CH in mice by stimulating the APC function of epidermal LC.

Animals↗
PubMed1993

Epidermal Langerhans cells are resistant to the permeabilizing effects of extracellular ATP: in vitro evidence supporting a protective role of membrane ATPase.

Extracellular adenosine 5'-triphosphate (ATPo) can induce pore formation in cell membranes, leading to cell permeabilization and eventual cell death. In this study, we examined the sensitivity of human epidermal Langerhans cells to ATP-induced permeabilization and tested the possibility that the Mg(++)- or Ca(++)-dependent plasma membrane ectonucleotidase (mATPase) on Langerhans cells provides protection against the cytotoxic effects of ATPo. Membrane permeability was assessed by using the fluorescent tracer propidium iodide, which confers red nuclear fluorescence to permeabilized cells. Langerhans cells were identified within human epidermal cell suspensions with fluorescein isothiocyanate-conjugated MoAb against CD1a or human leukocyte antigen-DR (HLA-DR) antigens. Cultured human keratinocytes and J774 macrophages were both highly sensitive to permeabilization induced by incubation with ATP (0.5 to 20 mM at 37 degrees C), whereas Langerhans cells were relatively resistant. The non-hydrolyzable ATP analog, adenosine 5'-(beta,gamma-imido) triphosphate, but not other nucleotides such as ADP, AMP, GTP, or UTP, was also able to induce permeabilization comparable to that of ATP, thereby suggesting that ATP hydrolysis is not required for this effect. ATP4- is the moiety most likely responsible for permeabilization, because propidium iodide uptake occurred only when the pH of the medium was > or = 7.4. Permeabilization induced by ATP was augmented by chelation of divalent cations with ethylene-diamine-tetraacetic acid and by the addition of lanthanum or cerium (0.01 to 1 mM). Finally, incubation with the adenosine analog, 5'-p-fluorosulfonylbenzoyl-adenosine (1 mM), inhibited mATPase staining of Langerhans cells in human epidermal sheets, but markedly augmented ATP-induced permeabilization of Langerhans cells. The results indicate that epidermal LC are resistant to the lytic effects of ATPo and that mATPase is involved in such resistance.

Adenosine Triphosphatases↗
PubMed1988

Comparative studies between in vitro and in vivo effects of human beta-interferon on natural killer activity and its relevance to immunochemotherapy.

A good correlation was found between in vivo and in vitro responses of peripheral MNC from breast cancer patients and the NK boosting effect of human beta IFN. In vitro immunochemistry studies showed that marked antitumor effects were obtained against cultured cancer cells when a widely used chemotherapeutic agent such as 5-FU was combined with nonsensitized spontaneously cytolytic MNC, preactivated in vitro with beta IFN. These results suggest that the in vitro susceptibility assay of MNC to IFNs could be used for predicting favorable responses to immunochemotherapy regimens employing IFNs as immunomodulating agents.

Cytotoxicity, Immunologic↗
PubMed1988

Combined effects of host antitumor immune responses and chemotherapy. Studies with hexamethylmelamine.

The antitumor activity of hexamethylmelamine (HMM) was tested in various mouse tumor models in the presence or absence of host-vs-tumor graft responses. The drug was moderately active against Sarcoma-180 growing in different strains of non-sensitized mice. Strong protection was afforded when recipients were preimmunized with irradiated tumor cells 15 days before tumor challenge followed by HMM treatment. The drug did not show antitumor activity against two radiation-induced lymphomas of congenic mice of B10 background, inoculated into H-2 compatible hosts, or into mice incompatible for subregions of H-2. In this model HMM increased mortality of allogeneic mice presumably through impairment of host-vs-lymphoma graft resistance. In conclusion this study shows that synergistic or antagonistic effects can be obtained by combining chemotherapy with antitumor immune responses.

Altretamine↗
PubMed1985

Decline of natural cytotoxicity of human lymphocytes following infection with human T-cell leukemia/lymphoma virus (HTLV).

Cell-mediated natural cytotoxicity (CMNC) of fresh or long-term cultured lymphocytes collected from HTLV-positive patients or infected in vitro with the virus, was tested against K562 target cells. Severe depression of reactivity was found in fresh lymphocytes of three patients with advanced disease, in 12 in vitro established T-cell malignant lines, and two HTLV-infected cord blood (C5/MJ and C91/PL) lines. Moreover, all (eight) HTLV-1 infected cell lines listed showed a significant inhibition of CMNC of peripheral blood lymphocytes of healthy donors. Whether virus infection promotes the outgrowth of pre-existing suppressor cells and/or produce changes of the T-lymphocyte function is unknown.

Adult↗
PubMed1984

Increase of natural killer (NK) activity of mouse lymphocytes following in vitro treatment with cytosine-arabinoside.

The in vitro influence of cytosine-arabinoside (Ara-C) on mouse NK activity was studied treating effector cells, target cells or effector and target mixture with graded concentrations of the drug. Ara-C increased the NK efficiency of mouse splenocytes without enhancing the susceptibility of target cells or the cytolytic events when added to effector-target mixture. This phenomenon was confirmed with splenocytes collected from congenitally athymic (nude) or conventional donors of different ages, untreated or depressed or boosted for NK activity by various agents. In addition Ara-C increased the NK activity of spleen cells of nude mice deprived of nylon-adherent cells, and did not affect suppressor cells capable of inhibiting the lytic phase of NK process. The drug was able to significantly augment the binding ability of spleen cells to the NK-sensitive YAC-1 target. It was concluded that Ara-C would increase the efficiency of natural cytotoxicity presumably through a direct influence on effector lymphocytes.

Animals↗
PubMed1982

Vindesine in the treatment of refractory hematologic malignancies: a phase II study.

A phase II evaluation of vindesine (VDS) was carried out in 46 patients with hematologic malignancies refractory to conventional chemotherapy. Two VDS schedules were employed (at random): (A) a weekly bolus (5 mg/m2 i.v. X 4); (B) fractionated daily injections (0.5 mg/m2 i.v. q.12 h X 10, course to be repeated after 10-15 days). Complete and partial remissions were observed in acute lymphocytic leukemia (3/14 patients), acute non-lymphocytic leukemia (2/12 patients), chronic myelocytic leukemia in blastic crisis (4/12 patients) and non-Hodgkin's lymphoma (4/8 patients). Responses were seen with higher frequency in patients treated with the weekly bolus (42.8 vs 16%). Myelosuppression was the most relevant side effect in both schedules. Neurotoxicity occurred infrequently and was generally mild in degree. Further trials with VDS in combination with other drugs are recommended in hematologic malignancies.

Acute Disease↗
PubMed1982

Amplification of natural killer activity of mouse lymphocytes by vincristine.

The possible influence of Vincristine (VCR) on NK-mediated cytolysis has been studied pretreating effector (E) or target (T) cells with the drug or adding the agent to E + T mixture during the 18-hour assay. Substantial increase of cytotoxicity was found when VCR was added to E + T cells, but not when effector or target cells were pretreated with the drug. This phenomenon was confirmed with effector splenocytes of various strains of mice, including athymic nude donors deprived of plastic-adherent or nylon-wool adherent accessory cells. Moreover, the agent did not produce irreversible inactivation of the suppression activity of splenocytes collected from DBA/2 donors infected with Friend leukaemia virus.

Animals↗
PubMedDate not supplied

Selective growth of natural cytotoxic but not natural killer effector cells in interleukin-3.

Interleukin-3 (IL-3) can promote the proliferation of certain classes of lymphocytes distinct from those that are dependent on interleukin-2 (IL-2) for growth. Culture conditions for its production are identical to those required for IL-2 and in both cases the producer cell appears to be Thy 1.2+, Lyt1+, Lyt2- However, unlike the IL-2 responder cells, the cells that proliferate in IL-3 are generally Lyt2-. Here we have measured the natural cytotoxic (NC) activity as well as natural killer (NK) cell activity of the IL-3-dependent cells. Both of these activities are part of a repertoire of spontaneous cytotoxic functions found in mice that might serve in early defence against infectious agents or immunosurveillance against tumours in vivo. We report a new finding that IL-3 selectively maintains NC cells but not NK cells in culture. This is in contrast to the known requirement for IL-2 in NK cell growth. This provides a means of isolating NC cells from NK cells in the mouse as an initial step in the study of the relative contribution of these two cell types in tumour immunity.

Animals↗
PubMedDate not supplied

Influence of vindesine on the lytic phase of mouse natural cytotoxicity against human leukemic cells.

Vindesine (VDS), a structural analogue of Vinca Alkaloids, was found to increase the NK-mediated cytolytic effects of mouse lymphocytes against human K562 target cells in a 18-hr assay. Pretreatment of effector or target cells with the drug did not affect substantially the NK reaction. The phenomenon has been detected using splenocytes of either congenitally athymic or conventional euthymic mice of different strains. Effector lymphocytes deprived of cells adherent to plastic surface or to nylon-wool column were still competent for drug-mediated increase of NK function. It is suggested that modification of the membrane make-up of effector or target cells reversibly induced by VDS, would promote higher NK-mediated cytolytic effects.

Animals↗
PubMedDate not supplied

[Non-surgical treatment of liver trauma].

The aim of the study was to assess the role of non-operative treatment in haemodynamically stable patients with liver trauma. Over the period from 1996 to July 2000, out of a total of 2,048 patients with abdominal trauma, 124 open and 1,924 closed, we observed 77 hepatic lesions, consisting of 55 closed traumas and 22 penetrating traumas. Non-operative treatment was implemented in 18 patients (32.7%) with closed liver traumas. In addition to serial clinical examinations of the abdomen, the patients receiving non-operative treatment were submitted to thorough haemodynamic monitoring and complete blood counts in the intensive care unit. After an abdominal CT scan at entry, patients were submitted to abdominal ultrasonography 6, 12 and 24 hours after admission. Only two patients required transfusions, one presenting a pelvic fracture and the other a triple fracture of the femur, tibia and fibula. There was no mortality. A biloma was present in one case, successfully treated by means of a US-guided drainage puncture. It is patients with major cranial traumas that pose most problems for conservative treatment. Fifty percent of non-therapeutic laparotomies in our series were performed in patients with severe cranial traumas. It is precisely in these patients that an improvement in diagnostic capability is most desirable.

Adolescent↗