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N R Pellis

Publications and source records attributed to N R Pellis.

At least 37 records · Page 2Linked to original sources
PubMed1995

Impairment of lymphocyte locomotion in the tumor microenvironment and the effect of systemic immunotherapy with liposome-encapsulated muramyl-tripeptide-phosphatidylethanolamine.

The ability of the lymphocytes to move through the interstitium is obligatory to the immune response. We previously showed that tumor-infiltrating lymphocytes (TIL) from human melanoma and renal cell carcinoma demonstrate a dramatic decrease in their spontaneous locomotion through three-dimensional collagen gel when compared with peripheral blood lymphocytes (PBL) and lymph node lymphocytes. To determine if this decrease is caused by contact with tumor cells, or mediated through certain diffusible factors, we examined the effects of autologous tumor cells on the locomotion of PBL in a model system where tumor cells were separated from lymphocytes by a 3-mm layer of gelled collagen. After 21-22 h incubation in chamber slides, locomotion distances were assessed in the presence and absence of tumor and normal cells. In the presence of tumor cells, PBL from 14 of 18 patients displayed substantial (466.5 +/- 2.7 microns compared to control 568.9 +/- 10.9 microns, P < 0.001) loss of motility. Inhibition was more prominent in melanoma patients than in renal cell carcinoma patients. Thus the impaired locomotion previously observed in TIL was at least partially due to the presence of tumor. The locomotion of TIL was restored in four of five melanoma patients treated with liposome-encapsulated muramyl-tripeptide-phosphatidylethanolamine (L-MTP-PE). Furthermore, in six of seven examined L-MTP-PE-treated patients, an increase in intrinsic PBL locomotion during the first month of the therapy was observed. These results suggest that the environment of the tumor is not conducive to locomotion of advancing lymphocytes and the therapeutic intervention may ameliorate the loss of lymphocytic infiltration.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1993

Effect of surgery on peripheral blood lymphocyte locomotion through type I collagen.

BACKGROUND: Locomotion of peripheral blood lymphocytes (PBL) through peritumoral matrix is obligatory for tumor cell killing. The authors investigated the effect of surgery on lymphocyte locomotion and compared it with the effect on natural killer cell cytotoxicity (NKCC). METHODS: PBL from 12 patients with cancer were assessed for locomotion in Type I rat-tail collagen. Preoperative and postoperative locomotion (after 20 hours of incubation) and NKCC were estimated. RESULTS: Locomotion of lymphocytes through collagen increased significantly after operation in 6 of 12 patients, whereas only 1 of 12 had a decrease (P < 0.001). Short-term (20-hour incubation) exposure of the locomotory HSB cell line to patient plasma samples did not affect their migration. NKCC, as estimated against K562 target cells with the use of the 51Cr-release assay, decreased 5-50% after operation in 9 of 12 patients (P = 0.006). No correlation could be demonstrated between the changes in locomotion and NKCC (regression analyses), nor were identifiable clinical factors associated with these changes. CONCLUSIONS: Locomotion of PBL through collagen increases after operation in patients with cancer, whereas possibly independent factors may decrease postoperative NKCC.

Cell Movement↗
PubMed1993

Locomotion through three-dimensional type I rat tail collagen. A modified mini-assay.

There is an increased application of three-dimensional type I rat tail collagen as an in vitro model for the peritumoral matrix in analysis of lymphocyte migration. The increased demand prompted us to modify the previous methods. We here describe our 'mini'-setup of the collagen model assay, which uses only 1/20 the amount of collagen medium and the number of cells used in the conventional assay. The modified assay was tested for optimal collagen concentration in gel for upward and downward migration, for locomotion from a collagen-gel bead into a collagen overlayer for demonstration of the effect of inhibitors and for differentiation between locomotory properties of lymphocyte subpopulations. The results verify that the mini-assay is an applicable in vitro model, easily read and amenable to limited blood samples such as those obtained from cancer patients, and reflects well known in vivo events.

Animals↗
PubMed1992

Tumor-specific chemoimmunotherapy of murine fibrosarcoma using tumor-specific transplantation antigen, cyclophosphamide, and interleukin-2.

The anti-tumor effect of active specific chemoimmunotherapy, using butanol-extracted tumor-specific transplantation antigen (TSTA), cyclophosphamide (CY), and continuous intrasplenic infusion of interleukin-2 (IS-IL-2), was assessed in a C3H/HeJ murine methylcholanthrene (MCA)-induced fibrosarcoma model. Sole administration of TSTA induced tumor-specific, suppressor T cells in the spleens of mice bearing 3-day established tumors. Concomitant low-dose (20 mg/kg) CY treatment not only inhibited TSTA-mediated suppressor cell induction, but also evoked splenic lymphocytes of tumor-bearing mice to display tumor-specific cytotoxic activity. High-dose (200 mg/kg) CY abrogated the immunotherapeutic benefit. The immune effectors generated by TSTA plus CY bear the Thy 1, L3T4, Lyt 2 phenotype. Continuous IS-IL-2 infusion in combination with TSTA and CY induced tumor-specific Lyt 2+ cytolytic T cells, as well as the activation of L3T4+ cytostatic T cells. Thus, a triple regimen using TSTA, CY, and IS-IL-2 appears to augment CTL induction in tumor-bearing hosts undergoing stimulation of helper elements by TSTA and inhibition of suppressor cells by CY.

Animals↗
PubMed1990

Humoral modulation of lymphokine-activated killer (LAK)-cell induction in humans: IgG-related and non-IgG inhibitors in sera from cancer patients.

Soluble inhibitors of lymphokine-activated killer (LAK) cell induction were characterized and purified from serous fluids from healthy donors or from patients with advanced cancer. Inhibitory activity in sera from cancer patients was partially absorbed with protein A agarose or anti-human IgG agarose. Following absorption, residual inhibition varied with individual sera, suggesting the presence of IgG-related and non-IgG inhibitory factors, and the proportions varied in the patient population. IgG, purified by affinity chromatography from ascitic fluids, from plasma of cancer patients, and from plasma of healthy donors, significantly inhibited IL-2 induction of LAK cells in a dose-dependent manner. Irrespective of the sources, inhibitory activity resided in the high-molecular-weight IgG fraction composed of IgG aggregates and immune complexes, but not monomeric IgG. Commercially prepared human IgG in aggregated form, but not in monomeric form, inhibited LAK cell induction in a dose-dependent manner. In contrast, neither bovine IgG nor human albumin affected LAK cell induction, even at higher concentrations. Aggregated human IgG inhibited LAK cell induction in unfractionated peripheral blood mononuclear cells (PBMC) but not in monocyte-depleted peripheral blood lymphocytes (PBL). Despite extensive (greater than 99%) depletion of IgG by protein-G affinity chromatography, the serous fluid from cancer patients displayed significant inhibitory activity. Fractionation of the IgG-depleted inhibitory materials by Sephacryl S-300, high-pressure ion-exchange column (HPIEC) or gel-permeation chromatography (HPGPC) demonstrated a 65-kDa inhibitor, distinct from IgG. Affigel-blue affinity chromatography of the 65-kDa fraction depleted albumin but did not remove the inhibitory activity, suggesting that the 65-kDa inhibitor is not serum albumin nor an albumin-bound component. These results suggest that serous fluids from patients with advanced-stage cancer contain 2 distinct regulators for LAK cell induction: (I) aggregated IgG and (2) a 65-kDa inhibitor, distinct from albumin.

Antibodies, Anti-Idiotypic↗
PubMed1990

In vitro migration of lymphocytes through collagen matrix: arrested locomotion in tumor-infiltrating lymphocytes.

Antitumor immunity requires (a) extravasation of lymphocytes from the blood stream to interstitium, (b) locomotion through extracellular matrix to the site of the tumor, (c) effector cell recognition of the tumor target with cell/cell contact and binding of adhesion receptors, (d) T-cell receptor binding to histocompatibility and tumor antigens, and (e) tumor cell lysis. We hypothesize that the tumor microenvironment inhibits lymphocyte locomotion through extracellular matrix as one mechanism by which tumors may avert host defense. Lymphocyte locomotion was investigated in vitro using a three-dimensional collagen gel model. Fresh tumor-infiltrating lymphocytes (TIL) were obtained by enzymatic digestion of melanomas and renal cell carcinoma, and mononuclear cells were isolated by discontinuous Ficoll-Hypaque gradient. The lymphocytes were analyzed for motility from a point of origin between basal and overlay layers of collagen gel. Results showed that TIL migration was almost completely inhibited, compared with migration of normal and cancer patient peripheral blood leukocytes and lymphocytes from lymph nodes. Short-term (24-h) exposure of lymphocytes to cytokines during the assay in the collagen gel matrix had no effect on locomotor ability. Long-term (19, 30, or 35 days) culture of TIL in 200 units/ml of interleukin 2 reinstated locomotor ability. Short-term exposure of any of the lymphocyte populations to interleukin 1-alpha, interleukin 1-beta, interleukin 2, interleukin 3, interleukin 4, alpha-interferon, or gamma-interferon had no effect on migration. Thus, TIL display a uniquely arrested ability to locomote through collagen gel. Inhibition of the locomotion of infiltrating effector cells is possibly a mechanism by which the tumor evades the host immune system.

Antigens, CD↗
PubMed1990

The brain and the immune system: an intact immune system is essential for the manifestation of withdrawal in opiate addicted rats.

Gamma irradiation (500 rad) is often used to suppress the immune system in mice, rats and man. Recently, it was shown that irradiation prior to chronic morphine treatment, dramatically reduces the severity of naloxone-precipitated withdrawal in morphine-dependent animals. In the present study adoptive transfer of 2-6 x 10(8) splenocytes to irradiated rats prior to chronic morphine treatment restored the severity of all withdrawal signs precipitated by naloxone. In contrast, adoptive transfer of fractionated splenocyte subpopulations only partially restored withdrawal severity; and transfer of irradiated splenocytes, red blood cells or diluted numbers of normal splenocytes did not have any observed restorative effect. These findings suggest that specific cellular activities or factors derived from lymphoid cells are required for the expression of opiate withdrawal.

Animals↗
PubMed1989

Monocyte-dependent, serum-borne suppressor of induction of lymphokine-activated killer cells in lymphocytes from melanoma patients.

Both phytohemagglutinin-induced cytotoxicity and recombinant-interleukin-2 (rIL-2)-induced lymphokine-activated killer (LAK) activity against noncultured melanoma cells were significantly reduced when peripheral blood mononuclear cells (PBMC) from patients with metastatic melanoma were incubated in RPMI medium 1640 and 10% autologous human serum instead of 10% fetal calf serum, while serum from either healthy donors or patients with primary melanoma did not affect the level of cytotoxicity. The serum-mediated suppression was not restricted by major histocompatibility complex and was time-dependent. Addition of 10% human serum from the patients with metastatic melanoma [HS-Pt(m)] to the culture of PBMC with rIL-2 at the same time or 1 day after incubation significantly inhibited LAK activity. However, addition of 10% HS-Pt(m) 2 or 3 days after incubation did not inhibit LAK activity. Incubation of PBMC for 2 h with a high dose (10(4) U/ml) of rIL-2 in the presence of 10% HS-Pt(m), followed by incubation in the absence of either rIL-2 or HS-Pt(m), did not affect LAK cell activity. These results suggest that HS-Pt(m) inhibits the early stage of LAK cell differentiation, rather than the binding of rIL-2 to PBMC or a later stage in the differentiation. In contrast to PBMC, monocyte-depleted peripheral blood lymphocytes exhibited comparable levels of LAK activity when cultured with rIL-2 either in 10% fetal calf serum, 10% human serum from healthy donors or 10% HS-Pt(m). Addition of purified autologous monocytes to the culture of monocyte-depleted peripheral blood lymphocytes with rIL-2 suppressed LAK cell induction when 10% HS-Pt(m) was present. Thus serum-mediated suppression of LAK cell induction is largely dependent on the presence of monocytes, which may produce a secondary inhibitor that acts on lymphocytes. Addition of indomethacin to the culture did not reverse this monocyte-dependent serum-mediated suppression in a majority of cases, suggesting that prostaglandin E2 does not have a major role in the suppression.

Cytotoxicity, Immunologic↗
PubMed1989

The immune system and opiate withdrawal.

Whole body exposure to 500 rad ionizing irradiation suppresses the immune system in rats. Moreover, when administered prior to chronic morphine treatment, irradiation exposure also dramatically reduces the severity of naloxone-precipitated withdrawal in morphine dependent animals. The reinstillment of 2-6 x 10(8) normal lymphoid immunocompetent cells to irradiated rats by adoptive transfer prior to chronic morphine treatment restores all withdrawal signs precipitated by naloxone injection. The data suggest that specific cellular activities or factors derived from lymphoid cells are required for the expression of opiate withdrawal, indicating that the immune system participates in the manifestation of opiate dependence.

Animals↗
PubMed1988

Effect of continuous administration of interleukin 2 on active specific chemoimmunotherapy with extracted tumor-specific transplantation antigen and cyclophosphamide.

Injection of purified human interleukin 2 (IL-2) directly into the spleen has been shown to potentiate the effect of specific chemoimmunotherapy, using butanol-extracted tumor-specific transplantation antigen (TSTA) and cyclophosphamide (CY) in a C3H/HeJ murine methylcholanthrene-induced fibrosarcoma model. Since IL-2 has a relatively short half-life in serum, continuous infusion of this lymphokine via the intrasplenic (i.s.), i.v., or i.p. routes was administered in an attempt to maintain therapeutic tissue levels. Primary hosts bearing 7-day (4-mm) or 14-day (greater than 10-mm) established s.c. methylcholanthrene F tumors were treated with weekly s.c. doses of 1 micrograms 1-butanol-extracted, isoelectrophoretically purified TSTA, the first of which was combined with a single i.p. injection of 20 mg/kg CY, and/or a 10-day continuous infusion of 120 units IL-2/day by one of the three routes. IL-2 delivered by all routes either by continuous infusion or by bolus injection augmented the chemoimmunotherapeutic efficacy of TSTA/CY against 7-day established tumors. On the other hand, the outcome of 14-day (greater than 10-mm) established tumors depended upon the method and route of administration of IL-2: continuous infusion via the i.v., i.p., or i.s. route prolonged host survival beyond that obtained by bolus administration. Continuous i.s.-IL-2 infusion greatly prolonged, continuous i.p.-IL-2 (120 units/day) slightly extended, and continuous i.v.-IL-2 had no effect on host survival. In a spontaneous pulmonary metastasis model following amputation of a tumor-bearing limb, only the triple regimen of TSTA/CY/i.s.-IL-2 decreased the number of lung colonies and prolonged host survival. Continuous infusion i.s.-IL-2 (120 units/day, 10 days) combined with TSTA/CY induced tumor-specific cytotoxic T-cells, as documented by in vitro 51chromium release cytolytic and in vivo local adoptive transfer assays. Based upon the residual local adoptive transfer assay activity of spleen cells depleted of specific lymphocyte subpopulations using monoclonal antibodies, the immune effectors generated by i.s.-IL-2 plus TSTA/CY bear the Thy 1+, Lyt2+ phenotype and those by i.p. or i.v.-IL-2 plus TSTA/CY, the Thy+, L3T4+ markers. Thus continuous i.s.-IL-2 infusion appears to augment cytotoxic T-cell induction in tumor-bearing hosts undergoing stimulation of helper elements by TSTA and inhibition of suppressor cells by CY.

Animals↗
PubMed1988

Active specific immunotherapy with extracted tumor-specific transplantation antigen, cyclophosphamide, and adoptive transfer of tumor-specific cytotoxic T-cell clones.

An L3T4-, Lyt2+ tumor-specific, cloned T-lymphocyte cell line (RTT-2) was isolated from a spleen cell population harvested from C3H/HeJ mice, following in vivo immunization against a syngeneic MCA-induced fibrosarcoma (MCA-F) and in vitro restimulation with 1-butanol-extracted, isoelectrophoretically purified MCA-F tumor-specific transplantation antigen (TSTA). RTT-2 required exposure to homotypic-extracted MCA-F TSTA in combination with low-dose IL-2 to maintain its specific cytotoxic activity in vitro. In vivo local adoptive transfer of RTT-2 caused specific neutralization of homotypic MCA-F, but not heterotypic MCA-D, tumor cells. Systemic in vivo transfer of RTT-2 alone augmented host resistance. In combination with a triple regimen of weekly doses of purified TSTA (1 microgram SC) and a single ip injection of CY (20 mg/kg), adoptive transfer of RTT-2 cells (1 X 10(7)) retarded the neoplastic outgrowth in and prolonged the survival of primary hosts bearing 3-, 7-, and 14-day established MCA-F tumors. In a spontaneous pulmonary metastasis model following amputation of a tumor-bearing limb, the triple regimen of TSTA/CY/RTT-2 markedly reduced the number of lung colonies. Thus RTT-2, which displays specific tumoricidal activity in vitro and in vivo, may afford a suitable tool to dissect T-cell receptors recognizing tumor markers on 1-butanol-extracted, MCA-F TSTA.

Animals↗
PubMed1988

The influence of hepatocellular function on NK and T cell tumoricidal activity.

Recent studies by this group have demonstrated that hepatocellular integrity is important in the preservation of host cellular immune function. This study evaluated the effect of experimental hepatocellular dysfunction (EHD) on host antineoplastic defense mechanisms. In nonspecific immune studies, we examined the effect of EHD on Wistar Furth (WF) natural killer (NK) cell cytotoxicity; in specific immune studies, we assessed WF C3H/HeJ lymphocytic responsiveness to both T cell mitogen and unmodified syngeneic fibrosarcoma. In concurrent studies, we evaluated the effect of EHD on interleukin-2 (IL-2) synthesis, an important NK and T cell trophic factor. WF rats and C3H/HeJ mice were assigned to three groups: EHD induced by bile duct ligation, sham, and normal control (NC). At day 21 serum bilirubin, WF NK cytotoxicity to YAC-1 tumor cells, WF and C3H/HeJ lymphocytic responsiveness to phytohemagglutinin (PHA) and syngeneic MCA-fibrosarcoma (MCA-F), and WF T-helper IL-2 production were determined in respective groups. Serum total bilirubin was elevated in EHD rats and mice with respect to controls (p less than 0.01). Wistar Furth cytotoxicity to the YAC-1 tumor cells was depressed in EHD animals with respect to sham and NC groups at 12.5:1 (p less than 0.01), 25:1 (p less than 0.05), 50:1 (p less than 0.05), and 100:1 (p less than 0.05) effector/target cell ratios. WF T cell responsiveness to PHA was depressed in EHD with respect to controls (p less than 0.01). C3H/HeJ lymphoproliferative response to MCA-F tumor antigen was also depressed in EHD animals when compared with control groups with the addition of 12.5 X 10(3) (p less than 0.05) and 50 X 10(3) (p less than 0.05) MCA-F cells. These impairments in NK and T cell function in EHD could not be attributed to diminished IL-2 production (EHD vs sham and NC: 112,141 +/- 5232 vs 106,691 +/- 1419 and 120,759 +/- 3248 cpm, respectively). These results demonstrate that hepatocellular failure compromises NK and T cell tumoricidal function, an effect not resultant on diminished T helper IL-2 production.

Animals↗
PubMed1988

Recombinant interleukin 4 (RIL4) inhibits interleukin 2-induced activation of peripheral blood lymphocytes.

Recombinant interleukin 4 (rIL4) inhibited the proliferation and induction of lymphokine activated killer (LAK) cells in human peripheral blood mononuclear cells (PBMC) cultured in recombinant interleukin 2 (rIL2). Other recombinant cytokines, such as rIFN gamma, rTNF alpha, rIL1, and rIL3, did not inhibit LAK cell induction. rIL4-mediated suppression was dose dependent. As little as 1 U/ml of rIL4 significantly decreased both LAK activity and proliferation of cells induced by incubation of PBMC with 200 U/ml rIL2. Suppression was specific for the induction phase of LAK activity, because rIL4 did not suppress the cytotoxic capability of previously activated LAK cells. rIL4 directly suppressed rIL2-induced activation of precursors into LAK cells, since it inhibited both rIL2-induced proliferation and LAK cell activity in LGL-enriched cell fractions or in purified CD16+ NK cells. Suppressive effects of rIL4 were overcome by adding rIFN gamma to the culture. These results suggest that rIL4 is a potent inhibitor of rIL2-induced activation of PBL, and that the net LAK response in the host may be a function of the production of IL-2, IL-4 and rIFN gamma.

Cell Division↗
PubMed1988

Endotoxemia and cholestasis.

Endotoxemia has been incriminated as a major cause of morbidity and mortality in patients with obstructive jaundice. It has been postulated that absence of gastrointestinal bile salt flow in cholestasis enhances portal absorption of bacterial endotoxin from the intestine, thereby predisposing the host to endotoxemia and its complications. This study re-evaluates this pathologic mechanism, using new quantitative chromogenic and conventional qualitative limulus techniques for the detection of bacterial endotoxin. Female Sprague-Dawley rats underwent either ligation of bile duct or sham operation. Serum total bilirubin, serum bile acid and intestinal bile acid concentrations were determined seven, 14 and 21 days after operation. Chromogenic and conventional qualitative limulus lysate endotoxin determinations were simultaneously performed on post-operative days two, seven, 14 and 21. Serum total bilirubin and bile acid concentrations were elevated and intestinal bile acid levels depressed at days seven, 14 and 21 (p less than 0.05). Results of quantitative and qualitative limulus studies failed to demonstrated the coexisting development of portal or systemic endotoxemia in rats with the bile duct ligated after diminution of flow of gastrointestinal bile salt. These data refute the hypothesis that flow of gastrointestinal bile salt enhances portal absorption of intestinally derived endotoxin and suggest alternative mechanisms are involved in the pathogenesis of endotoxemia in obstructive jaundice.

Animals↗
PubMed1987

Participation of lymphoid cells in the withdrawal syndrome of opiate dependent rats.

Treatment of rats with 500 Rads whole-body ionizing irradiation prior to chronic administration of morphine reduced the severity of the naloxone induced withdrawal signs. In contrast, adoptive transfer of 2-6 X 10(8) lymphoid cells to irradiated rats prior to chronic morphine treatment completely restored the ability to manifest the withdrawal signs precipitated by naloxone. These observations offer the possibility that the immune system participates in opiate addiction.

Animals↗
PubMed1987

Expansion of tumor-specific cytolytic T lymphocytes using in vitro restimulation with tumor-specific transplantation antigen.

Tumor-specific T lymphocytes (CTL) induced by in vivo immunization of C3H/HeJ mice with the syngeneic methylcholanthrene (MCA)-induced fibrosarcoma MCA-F were expanded in vitro by restimulation with 1-butanol-extracted, isoelectrophoretically purified, tumor-specific transplantation antigen (TSTA) in combination with purified rat interleukin-2 (IL-2) and fresh, syngeneic, 2000-R-irradiated, adherent splenic antigen-presenting cells (APC). The cultured immune T-cell population, containing 40-55% Lyt 2+ and 40-60% L3T4+ cells, displayed TSTA-specific proliferative and cytotoxic activities in vitro. The expanded T cells appear to recognize butanol-extracted TSTA in association with specific H-2 class I antigens, as revealed by the benefit of syngeneic over allogeneic cells as APC and by the adverse effect of depletion using anti-H-2K, but not anti-Ia, monoclonal antibodies. In adoptive transfer assays in vitro, expanded T cells specifically neutralize homotypic, but not heterotypic, tumor growth in vivo. Based upon the effects of depletion of T-lymphocyte subpopulations using monoclonal antibodies, the Lyt 2+ cytotoxic T lymphocytes (CTL) appear to display greater in vivo neutralizing activity than L3T4+ T cells. Thus in vitro stimulation of in vivo-immunized T cells, using butanol-extracted TSTA in combination with IL-2 and syngeneic APC, expands tumor-specific CTL.

Animals↗
PubMed1987

Differential modification of morphine and methadone dependence by interferon alpha.

Subcutaneous implantation of a pellet of methadone was presented as a novel method for the establishment of physical dependence upon this agent and it was compared to (1) the state of physical dependence induced by multiple injections of methadone, administered over several days, and (2) the dependence established by injections of morphine and the implantation of a morphine pellet. Comparable signs of drug dependence were observed in rats treated with both morphine and methadone following the administration of the opiate antagonist naloxone. The administration of interferon-alpha significantly attenuated the severity of the withdrawal syndrome in dependent rats after chronic exposure to morphine and to a lesser extent after morphine and methadone in combination. In contrast, alpha interferon did not affect 6 of the 7 abstinence signs in animals dependent upon methadone alone. The observations suggest that the states of physical dependence upon morphine and methadone may be separate phenomena that involve different physiological mechanisms. Thus, interferon may be a useful adjunct in the treatment of subjects dependent upon morphine but not in those dependent on methadone.

Animals↗