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At least 883 records · Page 49Linked to original sources
PubMed1990

Anti-viral immunity induced by recombinant nucleoprotein of influenza A virus. III. Delivery of recombinant nucleoprotein to the immune system using attenuated Salmonella typhimurium as a live carrier.

A plasmid encoding the influenza nucleoprotein gene from A/NT/60/68 virus was transduced into the attenuated Salmonella typhimurium aroA- strain SL3261. The bacterial vector expressing the viral gene product was able to induce both humoral and cell-mediated immune responses to the nucleoprotein antigen. CD4+ virus-specific T cells capable of proliferation were readily induced and, in some circumstances, class II major histocompatibility complex (MHC)-restricted cytotoxicity was detected. However, virus-specific class I MHC-restricted cytotoxic T lymphocytes (CTL) were not detected after such immunization. Mice immunized orally with the nucleoprotein-expressing bacteria mounted a strong anti-viral antibody response and spleen cells from such mice proliferated specifically to virus challenge in vitro, producing interferon-gamma (IFN-gamma) and interleukin-2 (IL-2). Orally immunized mice showed significant protection from challenge infection with influenza virus if the mice were also boosted intranasally before infection.

Animals↗
PubMed1990

Detection of neutrophil-activating peptide NAP/IL-8 and NAP/IL-8 mRNA in human recombinant IL-1 alpha- and human recombinant tumor necrosis factor-alpha-stimulated human dermal fibroblasts. An immunocytochemical and fluorescent in situ hybridization study.

A neutrophil-activating peptide (NAP)/IL-8 produced by LPS-stimulated human peripheral blood monocytes was biochemically purified and functionally characterized by different investigators. Work conducted in our laboratory showed that NAP/IL-8 as well as variants of this peptide are produced by a variety of cells (e.g., monocytes, T lymphocytes, endothelial cells) and that lesional psoriatic scales contain large amounts of biologically active NAP/IL-8. We now investigated human dermal fibroblasts for production of NAP/IL-8. The peptide was detected by immunocytochemistry by using the mAb 46E5. NAP/IL-8 mRNA was visualized by high resolutive fluorescent in situ hybridization with biotinylated antisense/sense RNA probes. Among the various stimuli used [human (h)rIL-1 alpha, hrTNF-alpha, hrIL-3, hr-granulocyte-macrophage-CSF, LPS, FMLP, and platelet-activating factor (PAF)] only hrIL-1 alpha (100 U/ml) and hrTNF-alpha (100 ng/ml) induced the transcription and translation of NAP/IL-8. In contrast to monocytes, LPS was without effect in cultured human dermal fibroblasts. Both NAP/IL-8 and NAP/IL-8 mRNA were found in the cytoplasm adjacent to the nucleus, but interestingly NAP/IL-8 mRNA was not restricted to the cytoplasm. In positive cells only two small bright spots were randomly distributed in the nucleus. Most likely these spots represent transcription sites where NAP/IL-8 mRNA is accumulated during gene expression. Our observations show that stimulation of dermal fibroblasts with the cytokines hrIL-1 alpha and hrTNF-alpha results in expression of IL-8.

Cell Compartmentation↗
PubMed1987

Colony inhibitory effect of recombinant human tumor necrosis factor (rH-TNF) and/or recombinant human interferon (rH-IFN)-alpha, -beta and -gamma on human lung cancer cell lines.

This study was conducted to assess, by continuous exposure, the inhibitory effects of rH-TNF and rH-IFN-alpha, -beta and -gamma, either alone or in combination, on the colony formations of human lung cancer cell lines. The cell lines tested were PC-7 and PC-9 (adenocarcinoma), PC-10 (squamous cell carcinoma) and PC-13 (large cell carcinoma). Additional experiments were performed with L929 (transformed murine fibroblast), because of its known high sensitivity to TNF. rH-TNF inhibited the colony formations of PC-10 and L929 even at a low concentration (10 U/ml). However, PC-7, PC-9 and PC-13 were resistant to rH-TNF. rH-IFN-alpha, -beta and -gamma inhibited the colony formation of PC-10 (less than 50% of control) at the highest concentration tested (10(4) U/ml), but only rH-IFN-beta inhibited that of PC-7. PC-9, PC-13 and L929 were insensitive to all three rH-IFNs, even at the highest concentrations tested. Combination effects of rH-TNF and rH-IFN-alpha or -gamma were synergistic only at the highest concentration combinations tested in PC-9. However, the maximum inhibition of colony formation of PC-7, PC-9 or PC-13 in any concentration combination treatment was less than 50%.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

Antiproliferative effect of IFN-gamma in immune regulation. III. Differential selection of TH1 and TH2 murine helper T lymphocyte clones using recombinant IL-2 and recombinant IFN-gamma.

Supernatants collected after primary or secondary stimulation of spleen cells contain different arrays of lymphokines. Primary supernatants from spleen cells stimulated with Con A or allogeneic spleen cells (MLC-SF) contain IL-2 but little IL-4 or IGN-gamma; in contrast, secondary MLC-SF contains IL-2 as well as substantial IL-4 and IFN-gamma. Our laboratory previously had always used secondary MLC-SF for cloning T cells, and had routinely obtained TH1 helper T lymphocyte clones. In the present study, when primary Con A-SF was used as source of growth factors, TH2 and not TH1 clones were preferentially derived. Considering the possibility that IFN-gamma may be one important factor in determining whether TH1 or TH2 clones are preferentially obtained, clone derivation was then performed either in the presence of rIL-2 or rIL-2 plus rIFN-gamma. The majority of clones derived using rIL-2 alone were TH2 cells, whereas the majority of clones derived using rIL-2 plus rIFN-gamma were TH1 cells. Using either procedure, some clones were obtained that produced IL-2, IL-4, and IFN-gamma. These data are consistent with our previous observations that IFN-gamma inhibits the proliferation of TH2 but not TH1 clones, and suggest that the presence of IFN-gamma during an immune response would result in the preferential expansion of helper T lymphocytes of the TH1 phenotype. Our procedure for the differential selection of TH1 and TH2 clones reactive with the same Ag should be useful for designing in vitro systems for studying the function of these cell subsets in specific immune responses.

Animals↗
PubMed1989

Phase I trial of recombinant interleukin-2 and recombinant beta-interferon in refractory neoplastic diseases.

Interleukin-2 (IL-2) and beta-interferon (beta-IFN) are cytokines with profound immunobiological effects on T-cell and natural killer (NK) cell activity; IL-2 also induces lymphokine-activated killer (LAK) cell cytotoxicity in humans. Both lymphokines induce antineoplastic activity against several refractory tumors. This Phase I study of 50 patients assessed the toxicities, maximally tolerated dose (MTD), effects on certain immune effector cells, pharmacokinetics of IL-2, and development of antibodies to the combination of subcutaneously administered IL-2 and intravenously administered beta-IFN. Fever was common. Indomethacin reduced the incidence and severity of fever and was necessary to prevent it from becoming dose-limiting. Hypotension occurred but never required pressors or produced complications. Constitutional symptoms, local skin toxicity at the site of IL-2 injection, generalized desquamation, eosinophilia, nausea, and vomiting were also observed. One patient had reversible renal dysfunction. Two patients experienced drug-related dyspnea without evidence of capillary leak syndrome; neither required intubation. Fluid retention and cardiotoxicity were not observed. The MTD was 5 x 10(6) U/m2 s.c. of IL-2 and 2 x 10(6) U/m2 i.v. of beta-IFN when given in combination. Enhancement of in vivo NK cell cytotoxicity and proliferation of T4+, T8+, and NK cells occurred. In vivo induction of LAK cell cytotoxicity was observed in three patients. Four patients developed nonneutralizing anti-IL-2 IgG antibodies, but none developed antibodies to beta-IFN. Peak IL-2 serum levels typically occurred 4 h following drug administration. Serum levels were within a factor of 3 of the peak level in the period studied, 1-6 h postinjection. No complete responses occurred. One patient with rectal cancer and one with transitional cell carcinoma each had a partial response, and 13 other patients (5 with renal cell, 4 with colorectal, and 4 other cancers) had stable disease. Induction of NK cell cytotoxicity was seen more commonly in patients with stable disease than in those with progressive disease. Combined administration of these agents is feasible with acceptable toxicity, and Phase II trials are warranted.

Adult↗
PubMed1988

In vivo effects of recombinant IL-2. I. Isolation of circulating Leu-19+ lymphokine-activated killer effector cells from cancer patients receiving recombinant IL-2.

This study was designed to isolate and phenotypically characterize lymphokine-activated killer (LAK) cells generated in vivo during administration of high dose rIL-2 to cancer patients. The development of circulating LAK effector cells in these patients was demonstrated by the ability of fresh PBL to exhibit lytic activity against the NK-resistant Daudi cell line and fresh tumor cells without prior in vitro culture with rIL-2. Kinetic studies demonstrated that circulating LAK effector cells are detectable 4 to 6 wk after the initiation of rIL-2 therapy. Cells isolated by FACS revealed that circulating LAK cells are Leu-19+, Leu-17+ but CD5-. We have previously reported that circulating Leu-19+ cells are heterogeneous with regard to the expression of CD16 and CD8. Since sorting of cells expressing Leu-19 and either low quantities of CD8 or CD16 resulted in cytolytic activity in both the positive and negative fractions, these latter two markers do not identify subpopulations of Leu-19+ cells with or without LAK cytolytic activity. Although all LAK cells generated in vivo were Leu-19+, we generated LAK cells from the Leu-19- subpopulation after in vitro culture with rIL-2, suggesting that at least some of in vitro generated LAK cells are derived from Leu-19- precursor cells. These LAK cells did not, however, express the Leu-19 surface marker. Based on the functional data reported in this paper, we conclude that circulating LAK effector cells are a phenotypically heterogeneous population that express surface Ag in association with NK cells and not T lymphocytes.

Antigens, Neoplasm↗
PubMed1988

Transforming growth factor-beta 1 (TGF-beta 1) and recombinant human tumor necrosis factor-alpha reciprocally regulate the generation of lymphokine-activated killer cell activity. Comparison between natural porcine platelet-derived TGF-beta 1 and TGF-beta 2, and recombinant human TGF-beta 1.

We have investigated the ability of porcine-platelet-derived transforming growth factor-beta 1 (TGF-beta 1) to inhibit the generation of lymphokine-activated killer (LAK) cells by human rIL-2. The results demonstrate that TGF-beta 1, in a dose-related manner, significantly inhibits rIL-2-induced LAK cell activity against Daudi and COLO target cells and, to a lesser degree, against K-562 cells. Maximal inhibition was obtained by the addition of TGF-beta 1 at the time of culture initiation and, to a lesser degree, on day 1. Only minimal inhibition was obtained when TGF-beta 1 addition was delayed until day 2 of culture or when added directly into the LAK cell assay. Additional studies demonstrated that porcine platelet-derived TGF-beta 2 and human rTGF-beta 1 inhibited LAK cell generation similar to that obtained with TGF-beta 1. The inhibition of LAK cell activity by TGF-beta 1 was reversed by the addition of human rTNF-alpha at the initiation of culture. In addition, rTNF-alpha synergized with suboptimal levels of rIL-2 in the generation of LAK activity. After stimulation with rIL-2, LAK cells produced significant levels of IFN-gamma, TNF-alpha, and TNF-beta. TGF-beta 1 inhibited the production of these cytokines in a dose-related manner. The results extend the previous known activities for human rTNF-alpha and TGF-beta 1 and further demonstrate the reciprocal relationship between these two molecules in the regulation of certain immune functions.

Adjuvants, Immunologic↗