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T S Kupper

Publications and source records attributed to T S Kupper.

At least 91 records · Page 5Linked to original sources
PubMed1988

Generation of an anti-interleukin 2 factor in healing wounds.

Previously we have noted that fluid obtained from ten-day-old healing wounds noncytotoxically inhibits the blastogenesis of lymphocytes in response to mitogens or antigens. Since these lymphocytic responses are interleukin 2 (IL-2)-mediated, we looked for a specific IL-2 inhibitor in wound fluid. We have found that wound fluid blocks the response of thymic lymphocytes and of two cloned T-helper cell lines (D10 and HT2) to exogenous human recombinant IL-2. The wound fluid enhances fibroblast proliferation, thus demonstrating that its proliferative inhibitory activity is specific for lymphocytes. The findings suggest that wound fluid contains a factor that impairs lymphocyte response to IL-2, probably at the receptor or postreceptor level.

Animals↗
PubMed1988

Keratinocyte derived T-cell growth factor (KTGF) is identical to granulocyte macrophage colony stimulating factor (GM-CSF).

Keratinocyte derived T-cell growth factor was initially described as a product of cultured neonatal keratinocytes and keratinocyte cell lines that induced the proliferation of HT-2 cells, a murine T-cell line that responds to IL-2 and IL-4 by incorporating 3H-Thymidine. Subsequently, KTGF has been purified to high specific activity and found to be distinct from IL-2 and IL-4 by a variety of biochemical, immunologic, and immunochemical criteria. Because it was found that certain HT-2 cell lines also proliferated in response to GM-CSF, the present study asked whether KTGF was related to GM-CSF. In this study, we demonstrate that antibodies to recombinant murine GM-CSF completely neutralize the capacity of KTGF to induce HT-2 proliferation without interfering with IL-2 or IL-4 induced HT-2 proliferation. Furthermore, poly-A+ RNA homologous to murine GM-CSF cDNA as judged by S1 nuclease analysis was detected in Pam 212 cells, and protein serologically homologous to GM-CSF was found in Pam 212 conditioned medium. We conclude that KTGF is identical to GM-CSF. The T-cell activating properties of GM-CSF require further exploration.

Colony-Stimulating Factors↗
PubMed1988

Interleukin 1 binds to specific receptors on human keratinocytes and induces granulocyte macrophage colony-stimulating factor mRNA and protein. A potential autocrine role for interleukin 1 in epidermis.

Cultured human keratinocytes have been shown to produce IL-1 alpha and beta mRNA and protein. IL-1 biological activity has been identified in normal human epidermis; in vitro, most biologically active IL-1 resides in a cell-associated compartment. The potential for autocrine effects of IL-1 on human keratinocytes was assessed by measurement of keratinocyte IL-1 receptors. Both high- and low-affinity cell surface receptors that bound recombinant (r) IL-1 alpha and beta with comparable affinities could be identified on cultured human keratinocytes, using 125I-labeled rIL-1. Chemical crosslinking experiments identified a cell surface molecule of roughly 72,500 Mr that bound 125I-labeled IL-1, similar to the molecular weight of previously described IL-1 receptors on fibroblasts, B cells, and T cells. To assess the biological consequences of keratinocyte IL-1 binding, granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression was measured. The addition of exogenous rIL-1 alpha led to a dose-dependent increase in the accumulation of GM-CSF mRNA, as measured by a sensitive and specific S1 nuclease assay. This increase in mRNA was reflected in a marked increase in GM-CSF biological activity as measured by proliferation of blast cells from chronic myelogenous leukemia patients. The biological activity was completely inhibitable by an antibody to human rGM-CSF. GM-CSF activates mature neutrophils and macrophages and appears to enhance the efficiency of Langerhans cell antigen presentation to T cells. Release of IL-1 from injured or activated keratinocytes may lead to enhanced epidermal GM-CSF gene expression via an autocrine mechanism, thus enhancing local host defense.

Cells, Cultured↗
PubMed1987

Characterization of a keratinocyte-derived T cell growth factor distinct from interleukin 2 and B cell stimulatory factor 1.

Epidermal epithelial cells (keratinocytes) produce and secrete a variety of immunologically active cytokines. We have previously reported that both transformed (PAM 212) and normal murine keratinocytes produce a soluble factor which induces proliferation of the T cell line, HT-2. In the present study we sought to compare keratinocyte-derived T cell growth factor (KTGF) with other T cell growth factors, characterize its physicochemical properties, and substantially purify KTGF from PAM 212 conditioned medium. KTGF from PAM 212 conditioned medium was not inhibited by antibodies which block the effect of interleukin 2 (IL 2) (S4B6) or B cell stimulatory factor 1 (BSF 1) (11B11). KTGF is heat-stable, has an isoelectric point of 4.8, and a relative molecular mass of 16 to 23 kilodaltons under nonreducing conditions. KTGF activity was enhanced at least 41,413-fold by sequential hydroxylapatite bulk preparation, desalting by reversed-phase chromatography, gel filtration high pressure liquid chromatography (HPLC), and reversed-phase HPLC. Keratinocytes produce a T cell growth factor with physicochemical properties distinct from IL 2 and BSF 1. KTGF may play a role in regulating the growth and differentiation of T cells in the epidermis.

Animals↗
PubMed1987

Hemorrhage without tissue trauma produces immunosuppression and enhances susceptibility to sepsis.

To determine whether hemorrhage without major tissue trauma can itself produce immunosuppression, the effect of hemorrhage on the lymphocyte response to T-cell mitogen in endotoxin-resistant C3H/HEJ mice was measured. The mice were bled to achieve a mean blood pressure of 35 mm Hg, maintained at that level for one hour, and then adequately resuscitated. On days 1 through 10 thereafter, the proliferative responses of the splenocytes to concanavalin A were measured and allogeneic mixed lymphocyte reaction was performed. The proliferative responses to mitogen stimulation as well as the results of mixed lymphocyte reaction studies indicated that marked immunosuppression occurred at day 1. Immunosuppression persisted for at least five days following hemorrhage, as evidenced by mitogen stimulation assay. Another group of mice was subjected to sepsis three days after hemorrhage and resuscitation. The mortalities in the sham-hemorrhage and hemorrhage groups following sepsis were 58% and 100%, respectively. Thus, a significant depression of cellular immunity occurred following simple hemorrhage despite adequate resuscitation, and this immunosuppression enhanced the susceptibility to sepsis.

Animals↗
PubMed1987

Keratinocyte membrane-associated epidermal cell-derived thymocyte-activating factor (ETAF).

This study describes the association between secreted keratinocyte interleukin 1 (IL-1) and its presence on the keratinocyte cell surface. These properties were studied in normal and transformed human keratinocytes as well as in transformed murine keratinocytes. We will present evidence that the secretion of IL-1 by human and murine keratinocytes is associated with the presence of IL-1 on the keratinocyte membrane. In addition, although transformed murine keratinocytes secrete other cytokines, namely keratinocyte T-cell growth factor (KTGF) and IL-3, no KTGF or IL-3 activity can be demonstrated on the cell surface.

Animals↗
PubMed1987

Interleukin 1 gene expression in cultured human keratinocytes is augmented by ultraviolet irradiation.

Interleukin 1 (IL-1) is a family of polypeptides initially found to be produced by activated monocytes and macrophages that mediate a wide variety of cellular responses to injury and infection. Epidermal epithelial cells (keratinocytes) produce "epidermal cell-derived thymocyte activating factor" or ETAF, which has been recently shown to be identical to IL-1. Human epidermis is normally exposed to significant amounts of solar ultraviolet radiation. Certain ultraviolet wavelengths (UVB, 290-320 nm) are thought to be responsible for most of the immediate and long-term pathological consequences of excessive exposure to sunlight. In this study, we asked whether exposure to UVB irradiation induced IL-1 gene expression in cultured human keratinocytes. Cultured human keratinocytes contain detectable amounts of IL-1 alpha and beta mRNA and protein in the absence of apparent stimulation; these levels could be significantly enhanced 6 h after exposure to 10 ng/ml of 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Exposure to UVB irradiation with an emission spectrum comparable to that of sunlight (as opposed to that of an unfiltered artificial UV light source) significantly increased the steady state levels IL-1 alpha and beta mRNA in identical populations of human keratinocytes. This was reflected in the production of increased IL-1 activity by these cultures in vitro. In the same cell population, exposures to UVB irradiation did not alter the level of actin mRNA; therefore, the effect of UV irradiation on IL-1 represents a specific enhancement of IL-1 gene expression. Local increases of IL-1 may mediate the inflammation and vasodilation characteristic of acute UVB-injured skin, and systemic release of this epidermal IL-1 may account for fever, leukocytosis, and the acute phase response seen after excessive sun exposure.

Cells, Cultured↗
PubMed1986

Human keratinocytes contain mRNA indistinguishable from monocyte interleukin 1 alpha and beta mRNA. Keratinocyte epidermal cell-derived thymocyte-activating factor is identical to interleukin 1.

Keratinocytes produce an IL-1 like factor termed epidermal cell-derived thymocyte-activating factor (ETAF). In this study, we show that ETAF and IL-1 are identical by the following criteria: Both normal and malignant human keratinocytes contain mRNAs identical to monocytic IL-1 alpha and IL-1 beta mRNA, as determined by an S1 nuclease protection assay; and IL-1 activity in medium conditioned by these cells can be neutralized by antibodies specific for human IL-1. The IL-1 alpha and IL-1 beta mRNAs can be identified in cultured human keratinocytes in the absence of identifiable stimulation; this basal level of mRNA can be further induced to accumulate with certain defined stimuli. Cultured normal human keratinocytes (HFKs) contain 2-4 times more IL-1 alpha than IL-1 beta mRNA; in contrast, human peripheral blood monocytes contain 10-20 times more IL-1 beta than IL-1 alpha mRNA. The IL-1 activity released by these HFK can be neutralized by an antibody that neutralizes both alpha and beta IL-1, but not by an antibody that neutralizes only IL-1 beta. While human monocytes produce a large excess of IL-1 beta after appropriate stimulation, these data suggest that IL-1 alpha is a major (and may be the predominant) form of IL-1 produced by human keratinocytes.

Cell Line↗
PubMed1986

Depression of cellular immunity after major injury. Its association with posttraumatic complications and its reversal with immunomodulation.

This study examined a group of surgical patients with respect to the ability of their peripheral blood mononuclear cells to respond to phytohemagglutinin (PHA). Depression of the PHA response of more than 30% below baseline five to seven days after injury was found in 11 of 19 patients, and eight of them developed infectious complications. The addition of indomethacin to in vitro cultures resulted in an average enhancement of the PHA response of 37% baseline. Improvement at five to seven days with in vitro indomethacin was from 34% to 74% in infected patients. These data suggest that major injury can lead to depression of the PHA response, which correlates with the subsequent development of infectious complications. Indomethacin in vitro seems to be able to reverse or decrease this immunologic defect and deserves further study.

Adult↗
PubMed1986

Keratinocyte-derived T-cell growth factor: a T-cell growth factor functionally distinct from interleukin 2.

T-cell growth factor, more recently termed interleukin 2 (IL-2), is the product of activated T lymphocytes and is considered the principal trophic factor for T lymphocytes. The activity of IL-2 preparations is assessed by the degree to which they support the growth of various IL-2-dependent cell lines. We report that murine epidermal epithelial cells (keratinocytes) produce and release a factor that supports the growth of the helper-T-cell-derived, IL-2-dependent cell line HT-2. This substance, keratinocyte-derived T-cell growth factor (KTGF), does not support the growth of an IL-2-dependent cell line derived from cytotoxic T cells (line CTLL-2). This differential effect on IL-2-dependent cell lines is unique to KTGF. KTGF has an apparent molecular weight of 25,000-35,000 and has properties similar to those of conventional IL-2 by reversed-phase and gel-filtration HPLC analysis. However, even highly purified KTGF fails to stimulate the proliferation of CTLL-2 cells. The observation that epidermal epithelium produces a trophic factor for T lymphocytes may help explain the basis for preferential proliferation of T cells in the microenvironment of skin in certain dermatologic disorders. Further, it suggests that different IL-2-dependent T-cell lines may have distinct growth requirements and that non-lymphocyte cell types may produce factors capable of maintaining the growth of T cells.

Animals↗
PubMed1986

Hydrocortisone reduces both constitutive and UV-elicited release of epidermal thymocyte activating factor (ETAF) by cultured keratinocytes.

Epidermal thymocyte activating factor (ETAF) is spontaneously released into the media by PAM 212 and A 431 cell lines and cultured normal human keratinocytes. ETAF from all 3 cell types can substitute for interleukin 1 (IL-1) in the augmentation of proliferation of a helper T-cell clone (D10.G4.1) induced by mitogen. Hydrocortisone (HC) substantially reduces the release of ETAF by these keratinocytes and, further, appears to induce the release of an inhibitor of lymphocyte activating factor activity of IL-1. Irradiation with UVC causes increased ETAF release into the media. Hydrocortisone abrogates this effect. Thus HC reduces both constitutive and elicited release of ETAF. ETAF plays a major role in inflammation; the ability of HC to block ETAF release by keratinocytes may account for the anti-inflammatory effect of glucocorticosteroids on the skin.

Animals↗
PubMed1986

The human burn wound as a primary source of interleukin-1 activity.

It has been suggested that interleukin 1 (IL-1) may be elevated systemically after major burn injury. Several metabolic changes commonly observed in patients with burns can be attributed in part to elevated IL-1 production; these include temperature elevation, skeletal muscle proteolysis, and alterations in the production of certain serum proteins by the hepatocyte (e.g., albumin and acute phase reactants). In this article we describe a likely source of this elevated IL-1 activity: the burn wound. Fluid taken from blisters on thermally injured skin early after burn injury contains substantial amounts of IL-1. This activity is less apparent in certain blister fluid (BF) samples, probably because of the presence of an inhibitor(s) of lymphocyte proliferation. However, after gel filtration high-performance liquid chromatography, the IL-1 actively elutes at a molecular weight of 15,000 to 20,000 daltons and can be blocked with an antibody to IL-1. We suggest that the source of this IL-1 activity is the injured keratinocyte and that release of this IL-1 systemically is inevitable. We postulate that release of IL-1 from the wound into the systemic circulation accounts in part for the metabolic changes outlined above. Furthermore, since epidermal IL-1 is a potent T cell chemoattractant, we believe that burn wound IL-1 may affect sequestration of T cells near the burn wound, resulting in T cell lymphopenia.

Blister↗
PubMed1985

A burn induced Ly-2 suppressor T cell lowers resistance to bacterial infection.

Suppressor T cell activity after major burn injury in a murine model has been well characterized. Suppressor cells have also been demonstrated in patients after major burn, and suppressor cell activity has been temporally correlated with septic episodes. A splenic Ly-2 T suppressor effector (Tse) cell appearing 7 days after a 30% full thickness burn has been identified in a murine model. A rat monoclonal antibody (14-8c3-12) directed against a factor produced by the Tse cell (Tsef) can enhance depressed in vitro mixed lymphocyte reaction (MLR) responses of Day 7 burn spleen cells without enhancing control spleen cell activity. Additionally, 14-8c3-12 can block the suppressive effect of these burn T cells on normal T cells. A cecal ligation and puncture (CLP) model using a 25-gauge needle (LD15) was used to assess the contribution of burn T cells to post-CLP mortality. Normal spleen cells injected into syngeneic recipients followed by CLP did not affect mortality (13%). Burn spleen cells injected into normal recipients enhanced mortality sixfold (90%) after CLP. The effect could be reversed by removing Ly-2 T cells (30% mortality) but not Ly-1 T cells (100% mortality) prior to cell transfer. Simultaneous injection of 14-8c3-12 antibody with burn T cells reduced mortality after CLP significantly (20%). Injection of 14-8c3-12 did not improve survival after CLP in control animals not injected with burn T cells (20%). Ly-2 T suppressor effector cells found in the spleens of mice 7 days postburn enhance the lethality of a purely bacterial septic challenge. A monoclonal antibody to the Tsef can reverse this effect in vivo.

Animals↗
PubMed1985

Defective antigen presentation to a cloned T helper cell by macrophages from burned mice can be restored with interleukin-1.

T helper (Th) cell dysfunction occurring very early (i.e., 24 to 72 hours) after a 30% full-thickness burn in a murine model cannot be attributed to suppressor T cell activity. Th cell activity is influenced by the activity of antigen-presenting cells (APCs). These cells process antigen and present a complex of antigen and cell surface Ia to the T cell. Additionally, they elaborate interleukin-1 (Il-1), and these events lead to Th cell release of Il-2, expression of Il-2 receptors, and proliferation of Th cells. We examined the contribution of APCs to postburn Th cell dysfunction by using mitomycin C-treated spleen cells from normal and burned mice as an APC population. The Th cell population consisted of a cloned Th cell line (D10.G4.1) that recognizes conalbumin in the context of I-Ak and proliferates when approximately stimulated. We found that APCs from burned mice induced significantly less Th cell proliferation (p less than 0.05). This was true of unfractionated spleen cells (50.4% of control) as well as positively selected (44.2% of control) or negatively selected (51.9% of control) splenic APCs. When cocultured with APCs from control mice, APCs from burned mice did not suppress control values of Th cell proliferation. Finally, the addition of murine Il-1 in vitro to cultures of burn-derived APCs, antigen, and T cell clone restored Th cell proliferation to control levels (from 38.3% to 92.8%) without nonspecifically enhancing similar cultures employing normal APCs. Il-1 in vitro did not improve Th cell function in the absence of antigen. Thus splenic APCs from mice exhibit defective antigen presentation early after burn injury. This defect is not a result of suppressor factor production by burn APCs and can be restored by Il-1 in vitro. Th cell dysfunction early after burn injury is thus due, in part, to APC dysfunction.

Animals↗
PubMed1984

A cyclophosphamide-sensitive suppressor T cell circuit induced by thermal injury.

The immunoregulatory events leading to the generation of suppressor T cells after burn injury were studied by means of a mouse burn model. Immunoresponsiveness was assessed on various postburn days with a primary in vitro mixed lymphocyte reaction (MLR). Responses of burned mice were depressed between 3 and 14 days after burn. Suppression became significant 5 days after burn and remained so through 14 days after burn. The Ly-t surface phenotype of T cells was studied on days 5 and 7 after burn. On day 5 burn, T cells responsible for suppression bore an Ly-1+, 2- phenotype. By postburn day 7 suppressor T cells bore an Ly-1-,2+ phenotype. These observations are consistent with the notion of feedback suppression after burn injury, wherein Ly-1+, 2- T cells induce a subset of Ly-1+,2+ T cells, thereby generating Ly-1-,2+ suppressor effector T cells. An attempt was made to uncouple the putative suppressor inducer and the suppressor effector using low doses of cyclophosphamide (CY). A single dose of 25 mg CY/kg resulted in transient restoration of depressed burn responses. By using multiple sequential doses of CY, this restorative effect could be prolonged through 8 days after burn. A dosage schedule that restores responses of burn cells without affecting responses of control cells is presented.

Animals↗