Search PubMedSearch

SEARCH · Search PubMed

Results for “Lymphokines”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Antibodies to guinea pig lymphokines. II. Suppression of delayed hypersensitivity reactions by a "second generation" goat antibody against guinea pig lymphokines.

A "second generation" antibody to a highly purified lymphocyte product was raised in a goat against material eluted from a rabbit anti-guinea pig lymphokine immunoadsorbent column. This anti-lymphokine serum, in constrast to anti-lymphocyte serum (ALS) did not appear to contain cytotoxic antibodies directed against membrane antigens on guinea pig lymph node lymphocytes. Furthermore, the anti-lymphokine serum did not inhibit the formation of spontaneous T rosettes nor significantly depress lymphocyte response to mitogens. The anti-lymphokine serum totally suppressed the delayed skin reactivity to PPD and contact sensitivity to DNCB when injected intradermally around the site of antigen challenge. By contrast, intradermally injected ALS did not appear to suppress the PPD response in sensitized guinea pigs. Intravenously and i.p. administered anti-lymphokine serum was somewhat less effective in suppressing the delayed skin response to PPD. The intradermal injection of the antiserum had no effect on nonspecific inflammation evoked by turpentine-olive oil or on the extravasation of circulating Evans blue evoked by intradermally injected histamine. Histologic examination of 24-hr DNCB-induced skin lesions from sensitized guinea pigs treated with intradermally injected anti-lymphokine serum showed marked reduction of mononuclear infiltration of the dermis and of epidermal lesions, as compared with skin sites taken from sensitized animals pretreated with normal goat serum. The anti-lymphokine serum injected i.v. also markedly reduced the perivascular infiltration of the dermis and subcutis in skin reaction sites from sensitized animals challenged with PPD. Intravenous treatment with ALS for 3 consecutive days caused extensive depletion of the paracortical areas of peripheral lymph nodes whereas treatment with normal serum and anti-lymphokine serum caused no such depletion. It is proposed that the anti-lymphokine serum is directed against activated lymphocyte products, one of them being MIF. These products are involved in the mediation of delayed hypersensitivity reactions. This is in marked contrast to ALS, the suppressive action of which appears to be central rather than peripheral.

Animals

Enhanced lymphokine production and lymphokine receptor expression in multiple antibody-stimulated human CD4+ peripheral blood lymphocytes.

Treatment of T lymphocytes with antibodies directed against the T cell receptor CD3 complex results in cellular activation that can be augmented by costimulation through other cell surface receptors. The activities of anti-CD3-stimulated human CD4+ PBL were compared to anti-CD3 plus anti-CD2-, anti-CD4-, or anti-CD11a (LFA-1)-stimulated cells. [3H]thymidine incorporation, lymphokine receptor expression, expansion of cell numbers, and lymphokine mRNA and protein were measured. Forty-eight hours after activation, costimulated CD4+ cells demonstrated increased numbers of cells positive for surface IL-2R alpha-chain, IL-2R beta-chain, IFN-gamma receptors, and TNF-alpha receptors. By day 6, costimulated cells exhibited a sevenfold greater expansion in cell numbers compared to cells stimulated with anti-CD3 alone. Anti-CD3 plus anti-CD11a stimulation consistently induced the highest secretion of IL-2 and IFN-gamma, whereas variation in secretion of TNF-alpha and IL-4 between different donors was noted. Analysis of lymphokine receptor mRNA demonstrated increased levels of mRNA for IL-2R alpha-chain and IFN-gamma receptor that preceded the phenotypic changes on the cell surface. In contrast, levels of IL-2R beta-chain and the TNF-alpha receptor mRNA decreased after stimulation. Amounts of IL-2, IL-4, and TNF-alpha, but not IFN-gamma, secreted also correlated with the levels of mRNA measured in the cells. Although costimulation through CD2, CD4, or LFA-1 appeared equally effective for the induction of the lymphokine receptors, these additional stimuli had a different impact on lymphokine secretion. These results indicate that specific control of lymphokine secretion and receptor induction can be another function of the CD2, CD4, and CD11a cell surface receptors. This control is evident at both transcriptional and post-transcriptional levels.

Antibodies

Prostaglandin E2 inhibits production of Th1 lymphokines but not of Th2 lymphokines.

PGE2 is known to inhibit IL-2 and IFN-gamma production from Th cells and is widely viewed as a general immunosuppressant. However, PGE2 was found not to inhibit IL-4 production from Th2 clones, and IL-5 production from these clones was slightly enhanced. The same results were obtained with short term T cell lines, which indicates that the lack of inhibition of IL-4 and IL-5 production by PGE2 is a general phenomenon. PGE2 functions by increasing cAMP levels through activation of adenylate cyclase. Despite its failure to inhibit lymphokine release, PGE2 was capable of increasing cAMP levels in Th2 cells, and forskolin, a direct activator of adenylate cyclase, also did not inhibit IL-4 or IL-5 production. These data indicate that the failure of PGE2 to inhibit IL-4 and IL-5 production was not due to an inability of PGE2 to induce an increase in intracellular cAMP, and suggested instead that the expression of IL-4 and IL-5 in Th2 cells is insensitive to elevated cAMP levels. When Th0 clones were examined, PGE2 was again found to differentially affect IL-2 and IL-4 production in three of five clones tested. In two additional Th0 clones, both IL-2 and IL-4 production were inhibited. These data suggest that lymphokine production may be regulated on two different levels. First, Th1- and Th2-associated lymphokines may be differentially sensitive to intracellular signals such as cAMP. Second, T cell subsets may exist, including subsets of Th0 cells, with different signaling pathways. In addition, our data suggest that PGE2 may play an important role in regulating the development of a response dominated by Th1- or Th2-associated lymphokines.

Animals

T cells in inductive and effector compartments of the intestinal mucosal immune system of nonhuman primates differ in lymphokine mRNA expression, lymphokine utilization, and regulatory function.

To define further the basis of T cell function in the inductive and effector limbs of the normal intestinal immune system, the capacity of mucosal lymphocytes to produce and use lymphokines and their effects on regulation of Ig production were determined in normal nonhuman primates. Northern blots of RNA from mitogen-activated lamina propria T cells contained more mRNA for IL-2 and IFN-gamma than did mesenteric lymph node T cells. In comparison with lymphocytes from peripheral sites, there was high expression of IL-4 and IL-5 mRNA in both mesenteric lymph node and lamina propria T cells. In studies of lymphokine utilization, T cells from lamina propria had high IL-2-induced but no IL-4-induced proliferative responses. In contrast, mesenteric lymph node T cells had high IL-4-induced and lower IL-2-induced proliferative responses compared with lamina propria T cells. Lamina propria T cells had higher helper activity in PWM-stimulated cultures and exhibited less inhibition by IL-4 than did mesenteric lymph node T cells. These data and previous studies suggest that T cells in an inductive site such as the mesenteric lymph node are a mixed population containing both "naive" cells with low potential for IFN-gamma and IL-2 production and differentiated cells with high potential for IL-4 and IL-5 production. In contrast, the data suggest that T cells in the effector compartment of the lamina propria are comprised primarily of differentiated "memory" cells that produce high levels of IL-2, IFN-gamma, IL-4, and IL-5, have high helper activity, and have a more limited ability to proliferate in response to lymphokines such as IL-4.

Animals

A high molecular weight cytotoxic lymphokine in supernatants of lymphokine-activated killer cells cross-reacts with transforming growth factor beta.

Supernatants of lymphokine-activated killer (LAK) cells were highly cytotoxic for melanoma A375 cells. A high-molecular-weight fraction was isolated from such supernatants by gel filtration on an S-300 Sephacryl column (Fraction 1; Fr1). The cytotoxic activity in Fr1 was heat- and acid-resistant and was completely abolished by a rabbit antibody against TGF-beta. We conclude that Fr1 contains TGF-beta or a cross-reactive molecule, associated with a high-molecular-weight carrier.

Animals

Lymphokines of T and B cells. I. Demonstration that T and B cells of tumor antigensensitised mice produce different lymphokines changing surface charge of target cells.

Lymphocytes from MC sarcoma-bearing mice were exposed to a soluble tumor antigen. The lymphokine-containing supernatant thus obtained was fractionated on Sephadex G-75. Fractions were tested for their activity to reduce the surface charge of indicator macrophages by cell electrophoresis technique. When unseparated spleen or lymph node cells were used the charge-reducing activity of the supernatant was found in three regions according to molecular weights of about 100,000, 60,000 - 35,000 and 13,000 Daltons. The appearance of activity was found to be time-dependent. As indicated by tests with separated lymphocytes both B and T cells appear to release charge-reducing activity.

Animals

Lymphokine-activated killer traffic assay and our preliminary clinical results of regional arterial infusion of lymphokine-activated killer cells for renal cell carcinoma.

In vivo distribution of radiolabeled lymphokine-activated killer (LAK) cells that were administered either through the caudal vein or the abdominal aorta of Lewis rats was studied. The LAK traffic study showed remarkable increase in radioactivity in several organs peripheral to the arterial injection site. We began treating the patients with metastatic renal cancer by means of regional arterial administration of LAK cells. This treatment was supported by the results of the traffic assay. Our regional LAK therapy, which involves a weekly leukapheresis in combination with daily systemic low dose interleukin-2 administration, has been in practice for over 2.5 years. Seven out of 12 metastatic lesions in the 7 patients treated showed regression. Two responding cases have been alive for over 2 years. Responding lesions were bone, muscle, para-aortic lymph node, and/or retroperitoneum. The regional arterial administration of LAK cells is local therapy. However, this mode of therapy could be useful for those patients with extrapulmonary nonresectable metastasis and at least one injectable feeding artery. This study shows our laboratory data concerning the localization of LAK cells transferred via arterial route and our clinical cases treated with regional arterial administration of LAK cells.

Animals

Mechanism of interferon gamma-induced protection of human gliosarcoma cells from lymphokine-activated killer lysis: division of lymphokine-activated killer cells into natural killer- and T-like cells.

The mechanism by which interferon gamma (IFN-gamma) decreases the susceptibility of the established cultured gliosarcoma line Gl-1 to lymphokine-activated killer (LAK) lysis was analyzed. The results of monolayer depletion and lectin-dependent cellular cytotoxicity assays by LAK cells revealed that the resistance to LAK lysis of IFN-gamma-treated Gl-1 cells is manifested at the stage of LAK cell target recognition alone. We have also divided LAK cells into populations of phenotypically natural killer (NK)- and T-like cells with monoclonal antibodies and complement, respectively. We have used these cells to examine the mechanism of IFN-gamma-induced protection of Gl-1 cells from LAK lysis in cold target inhibition, monolayer depletion, and direct binding assays. The results revealed that NK-like cells do not recognize IFN-gamma-treated Gl-1 cells as efficiently as they do untreated targets, whereas T-like cells show the opposite tendency. In conclusion, we have demonstrated that the IFN-gamma induced protection of tumor cells from LAK lysis is predominantly regulated by the target recognition of NK-like cells. On the other hand, IFN-gamma-treated tumor cells may bind to T-like cells but fail to trigger them to initiate further stages for lysis as effectively as NK-like cells.

Cell Division

Antibodies to guinea pig lymphokines. IV. Suppression of the mixed leukocyte culture reaction by anti-lymphokine globulin.

An antiserum, (anti-lymphokine globulin, ALyG) directed against highly purified products of activated lymphocytes, inhibits the proliferation of responding cells in guinea pig mixed leukocyte cultures ((MLC). This serum recognizes three newly synthesized lymphocyte products (one of them being migration inhibition factor (MIF) which are involved in the mediation of delayed hypersensitivity reactions in vivo. Since ALyG does not appear to contain cytotoxic antibodies against guinea pig lymphocyte antigens and its inhibitory activity cannot be removed by absorption with lymphoid cells it seems likely that the inhibition of MLC reactivity is not mediated by the lysis of stimulator or responder cells and its target is not the lymphocyte per se but possibly some factor elaborated during MLC response. By contrast, antisera with specificity for histocompatibility (H) antigens can inhibit the MLC when the appropriate H antigens are present on the responding and/or stimulating cell population. However, this inhibitory of the antisera can be effectively absorbed with lymphoid cells bearing the appropriate H antigens. The addition of ALyG even 48 hr after the initiation of culture results in a marked inhibition of MLC reactivity. This finding is consistent with the elaboration of a mitogenic factor or signal during the first 48 hr of culture and the delivery of this signal to the responding cell population. Thus, ALyG does not appear to interfere with the synthesis of this factor but must be present after its release in order to block responder cell proliferation. Furthermore, the stimulatory effect of this MLC mitogenic factor, but not of PPD-induced mitogenic factor on "third party" cells can be completely inhibited when the cells are cultured in the presence of ALyG. These findings suggest that the MLC-mitogenic factor in this system is identical to or cross-reactive with one or both of the newly synthesized molecules recognized by the ALyG.

Animals

Regulation of lymphokine-activated killer cell induction by human recombinant IL-1 receptor antagonist. Obligate paracrine pathway of IL-1 during lymphokine-activated killer cell induction.

IL-2-stimulated human lymphocytes, referred to as lymphokine-activated killer (LAK) cells, can develop a broad range of lytic activity against fresh tumor cells and cultured tumor cell lines. IL-1, a pleiotropic cytokine shown to synergize with IL-2 on LAK induction, is endogenously synthesized and secreted by LAK cells. Immunoblot analysis demonstrated that IL-2-stimulated PBL produced the 31- to 34-kDa pro-molecules of IL-1 within 24 h and maintained their expression for at least 96 h. The role of secreted IL-1 has been examined using rIL-1R antagonist (IL-1ra). The addition of IL-1ra to LAK activation culture resulted in dose-dependent inhibited lytic activity, which was more apparent in LAK cells cultured with higher doses of IL-2. However, IL-1ra had no effect on proliferative responses elicited in LAK cells by IL-2. Moreover, when IL-1 binding was blocked by IL-1ra, the expression of the IL-2R p55 subunit was reduced compared with control LAK cells. The effect of IL-1 binding blockade on expression of other cytokine mRNA was further examined by polymerase chain reaction analysis, and, specifically, inhibition of both TNF-alpha and TNF-beta mRNA expression by IL-1ra was observed in PBL stimulated with IL-2. The reduced biologic activity of TNF in culture supernatants correlated well with the inhibition of mRNA expression. These findings suggest that autocrine/paracrine IL-1 is involved in the initial generation of LAK activity and, in particular, that TNF expression could be induced via an IL-1 autocrine pathway.

Base Sequence

Immunotherapy of cancer with lymphokines and lymphokine-activated killer cells.

Our expanding knowledge of the immune system has provided a basis of rationality for immunotherapy. Some non-specific immunotherapy has achieved the status of standard treatment: interferon in hairy cell leukemia and chronic myelogenous leukemia, BCG in bladder cancer, and levamisole in colon cancer adjuvant therapy. Tumor infiltrating lymphocytes, moreover, offer a level of specificity heretofore unknown. Combined with the newly available synthetic cytokines that regulate the normal immune system there is the potential for a major breakthrough in biotherapeutics. Problems remain. We have yet to identify tumor antigens with the precision necessary for effective immunotherapy. Indeed, we have no assurance that tumors will regularly synthesize new antigens. In the broad spectrum of immune deficiency syndromes, we have yet to see an increase in the common epithelial tumors that account for the great bulk of human cancer. This suggests that we still have a great deal more to learn.

Cytokines

Heterogeneity in lymphokine profiles of CD4+ and CD8+ T cells and clones activated in vivo and in vitro.

Analysis of lymphokine mRNA expression and protein secretion by about 100 short-term alloreactive T-cell clones revealed marked heterogeneity in the combinations of lymphokines synthesized. This finding argues against a simple model in which T cells express either an unrestricted (Th0) or a restricted (Th1 or Th2) lymphokine profile. Lymphokine titers appeared to be normally distributed, with the percentage of positive clones for any one product determined by the threshold of detection. Accordingly, the observation that CD4+ clones on average produced higher titers of most lymphokines than CD8+ clones indicated that apparent differences between the lymphokine profiles of these two subsets were quantitative rather than qualitative. Patterns of lymphokine gene expression detected in whole tissues or by analysis of single cells and clones were markedly influenced by in vivo priming. Relative levels of expression of IL-4, IFN-gamma and GM-CSF in lymphoid tissues differed in mice undergoing a GvHR or following contact sensitization with OX or immunization with KLH in adjuvant. Consistent with the finding that IL-4 was the major lymphokine mRNA detected in lymph nodes of KLH-primed mice, most short-term KLH-specific clones derived from such mice also expressed IL-4. A similar approach to the detection of lymphokine-secreting T-cell precursors activated late in L. major infection showed that most clones from the L. major-resistant strain, C57BL/6, secreted IFN-gamma without IL-4 whereas most clones from the susceptible strain, BALB/c, secreted IL-4 without IFN-gamma. Differences were also noted in anti-CD3-induced IL-3 production at the single-cell level between CD8+ cells activated in the GvHR or against a tumor allograft. Con A-induced, filler cell-dependent cloning of CD4+ T cells from unprimed mice gave rise both to IFN-gamma-producing and to IL-4-producing clones. A requirement for an undefined, filler cell-dependent signal for development of IL-4-secreting clones was suggested by the finding that clones of normal CD4+ and CD8+ T cells activated in an anti-CD3-induced, filler cell-free system exclusively produced IFN-gamma and IL-3 without detectable IL-4 or IL-6. With a view to developing a single-cell approach to the analysis of lymphokine profiles of in vivo-activated T cells, sensitive assays for IL-3 and other lymphokines were used to measure secreting cells activated in the GvHR or against a tumor allograft.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals

Quantitative analysis of lymphokine expression in vivo and in vitro.

Constitutive lymphokine production by cells isolated from mice injected with keyhole limpet haemocyanin (KLH) or from mice undergoing an acute graft vs host reaction (GVHR) was very low, but could be markedly increased by T cell receptor (TCR) ligation. This suggested that in vivo levels of lymphokine production are much lower than those induced by in vitro stimulation. Serum lymphokine titres were consistent with this possibility, and analysis of lymphokine mRNA levels using S1-nuclease protection demonstrated that in vitro-stimulated cells from normal, KLH and GVHR mice all had markedly increased levels of lymphokine transcripts relative to levels found in vivo. A novel method combining limiting dilution analysis with polymerase chain reaction amplification of cDNA was developed that showed that these differences in levels of lymphokine production were due at least in part to differences in the frequencies of lymphokine mRNA-containing cells. Studies of the means by which differential lymphokine production is achieved demonstrated that CD4+, CD8+ and cytotoxic T lymphocyte (CTL) clones all express a common, restricted set of lymphokines in response to a defined in vitro stimulus, but that individual in vivo primed cells can express at least seven distinct patterns of lymphokine production.

Animals

Distinct regulation of lymphokine production is found in fresh versus in vitro primed murine helper T cells.

The kinetics of lymphokine RNA induction and secretion of biologically active lymphokine from CD4-enriched splenic T cell populations was investigated. Cells stimulated immediately after isolation from murine spleen ("fresh" T cells) and cells restimulated after 4 days of in vitro culture ("primed" T cells) were compared. Northern blot analysis and bioassays were used to analyze and quantitate production of eight lymphokines and the IL-2R. Fresh T cells produced high levels of IL-2 and low to moderate levels of IL-3, granulocyte/macrophage-CSF, and IFN-gamma. In vitro primed T cells produced IL-2, IL-3, IL-4, IL-5, IL-6, granulocyte/macrophage-CSF, IFN-gamma, and high levels of IL-2R RNA. Comparison of RNA levels and bioassays of supernatants from these populations indicated that primed T cells produced at least 10-fold more of six of the lymphokines than fresh T cells. Only IL-2 was produced in near equal amounts by fresh and primed T cells. There were also marked differences in the kinetics of lymphokine production by fresh and primed CD4+ T cells. After restimulation with Con A and PMA, primed cells produced a short burst of lymphokine RNA that peaked between 7.5 and 13 h and declined after 18 h. Fresh T cells lagged in the initial production of lymphokine RNA, with levels peaking 18 to 44 h after mitogenic stimulation. Depletion of CD4+ cells indicated that cells of helper phenotype were responsible for the majority of lymphokine production from the primed cells. Thus different subpopulations of Th cells defined by their respective ability to respond either directly (fresh T cells) or only after culture and restimulation (primed T cells) show different patterns of lymphokine gene regulation. Other studies suggest that the activity of "fresh" Th cells is due to a population with a "memory" phenotype, while the cells which require culture have a "precursor" phenotype. These distinct patterns of lymphokine gene regulation in the two populations of Th cells may account in part for differences seen in the kinetics and magnitude of the naive and memory immune responses which are regulated by Th cells.

Animals