Contact sensitization induces proliferation of heterogeneous populations of hapten-specific T cells

To characterize the T cells that are activated during the induction of contact hypersensitivity (CH), two sets of studies were conducted: 1) dinitrophenol (DNP)-specific proliferative responses of T cells in draining lymph nodes of BALB/c mice sensitized epicutaneously to dinitrofluorobenzene (DNFB) were examined, and 2) from these lymph node cells, DNP-specific T cells were cloned by limiting dilution microculture and analyzed by FACS for surface markers, by RT-PCR, HT2 bioassay and ELISA for cytokine expression at mRNA and protein levels respectively, and by proliferation assay for cytokine and antigen-presenting cell (APC) requirements. Our results show that alpha beta TCR-bearing T cells of both the CD4+ and CD8+ subtypes from lymph nodes of DNFB-skin-painted mice proliferate specifically to dinitrobenzene sulfonate (DNBS) in vitro. Four DNP-specific, CD4+ T-cell clones were characterized: clone 5S4 secreted IL-4 and required Il-4 for optimal growth; clone 5S10 secreted IL-2 and required IL-2 for optimal growth; clone 5S2 secreted IL-4 but required IL-2 for optimal growth; and clone 5S8 secreted IL-2 predominantly at 5 months, but switched to production of IL-4 at 7 months. All four clones secreted IL-10, and proliferated to DNBS when Langerhans cell (LC)-enriched epidermal cells were used as APC. These findings indicate that heterogeneous populations of DNP-specific T cells are activated in draining lymph nodes during the induction of CH to DNFB in BALB/c mice.

Cloning and expression of eel natriuretic-peptide receptor B and comparison with its mammalian counterparts

A comparative study of the natriuretic-peptide receptor NPR-B was performed by cloning and expressing, in COS-1 cells, the NPR-B receptor subtype from the eel gill which exhibited a strong C-type-natriuretic-peptide (CNP)-induced guanylate cyclase activity. Like other mammalian NPR-B receptors, the eel NPR-B receptor consisted of a ligand-binding extracellular domain, a hydrophobic transmembrane domain, a kinase-like domain and a guanylate cyclase domain. Sequence comparison among the eel and mammalian receptors revealed a relatively low similarity (approximately 44%) in the extracellular domain compared to a very high similarity (approximately 84%) in the cytoplasmic regulatory and catalytic domains. This low similarity allowed identification of the amino acid residues or candidate regions important for the ligand-binding activity. RNase protection analysis of the eel NPR-B mRNA demonstrated that the message was predominantly expressed in the liver and atrium as well as in the gill with moderate-to-small amounts in the brain, ventricle, esophageal sphincter, stomach, posterior intestine and kidney. The high NPR-B mRNA levels in the liver, atrium and gill were found to decrease markedly when eels were transferred from fresh water to seawater and kept there for 2 weeks. Since similar changes are known to occur in the ligand CNP levels when eels are facing osmotic challenges, the CNP/NPR-B system appears to play an important role in their successful adaptation to salinity changes.

Binding of anti-inflammatory alpha-melanocyte-stimulating-hormone peptides and proinflammatory cytokines to receptors on melanoma cells

alpha-Melanocyte-stimulating hormone (alpha-MSH1-13), a peptide derived from proopiomelanocortin, has remarkable anti-inflammatory and antipyretic activities. This peptide and a tripeptide that forms the COOH-terminal portion of the molecule (alpha-MSH11-13; Lys Pro Val) inhibit inflammation when given centrally or peripherally. Because of the similarity in their actions, the tripeptide has been presumed to be the amino acid message sequence underlying the effects of alpha-MSH1-13. To test the possibility that the two peptides occupy the same receptors, competitive binding experiments were performed with B16 mouse melanoma cells that are known to have alpha-MSH1-13 receptors. In these experiments, alpha-MSH11-13 did not inhibit binding of a radiolabelled alpha-MSH1-13 analog. This finding suggests that alpha-MSH1-13 and alpha-MSH11-13 exert their anti-inflammatory/antipyretic/anticytokine effects via stimulation of separate receptors. Because alpha-MSH inhibits the effects of several cytokines including inflammation caused by interleukin (IL)-6 and IL-8, the capacity of these cytokines to compete for alpha-MSH binding sites was tested. There was no evidence that these proinflammatory cytokines bind to alpha-MSH receptors on murine melanoma cells. Although further tests with host cells involved in inflammation are required, the latter result is the first evidence that the mechanism of anticytokine action of alpha-MSH does not depend upon peptide/cytokine competition for binding sites.

Impaired spatial learning by vasoactive intestinal peptide in Morris water maze task in the rat

Intracerebroventricular administration of vasoactive intestinal peptide (VIP) disturbed the learning by rats of the location of a platform submerged in a water pool. When the platform was removed from the pool, VIP injection produced marked impairment of the ability to find a previously learned location in the pool. This spatial memory impairment caused by VIP was restored by peripheral pre-administration of cerulein.

Open-field behavior of rats following intracerebroventricular administration of neuromedin B, neuromedin C, and related amphibian peptides

Neuromedin B (NMB) and neuromedin C (NMC) have amino acid sequences similar to those of various amphibian skin peptides and thus may elicit behavioral effects similar to those of bombesin. The present study was performed to determine the central effects of neuromedins (including pyro-NMB and pyro-NMC) in comparison with those of amphibian peptides using an open-field test situation. At 1 min after intracerebroventricular administration of the peptides, there was a marked decrease in the duration of locomotion, the distance moved, and rearing behavior, but a marked increase of excessive grooming and violent scratching. Pronounced behavioral changes were still observed 30 min after injection of the peptides, except for NMB. Thus, NMB seemed to be rapidly degraded by endogenous peptidases in the brain, suggesting that it might be the essential form of this neuropeptide family in the mammalian brain.

Keratinocyte-derived IL-7 serves as a growth factor for dendritic epidermal T cells in mice

Dendritic epidermal T cells (DETC) are CD3+, CD45+, CD4-, CD8-, TCR-V gamma 3/V delta 1+ T lymphocytes that reside in symbiosis with keratinocytes in mouse epidermis. To address mechanisms by which these cells survive and proliferate within the epidermal environment, we have tested the hypothesis that cytokines secreted by neighboring keratinocytes play relevant roles. The present study was conducted to determine whether keratinocytes produce biologically relevant amounts of IL-7, and, if so, to study its effects on DETC. The long term cultured DETC line, 7-17, and freshly isolated DETC exhibited dose- and time-dependent proliferative responses to rIL-7. These responses were blocked completely by anti-IL-7 antibodies, whereas anti-IL-2 had no effect, indicating that DETC respond to IL-7 by an IL-2-independent mechanism. Proliferative responses depended on the state of cell activation; DETC stimulated 2 to 5 days earlier with Con A proliferated optimally to added IL-7, whereas cells stimulated 10 days earlier did not proliferate. DETC that failed to proliferate responded to IL-7 by showing prolonged survival; cells maintained for 7 days with IL-7 alone retained their capacity to proliferate in response to Con A. Mouse epidermal cells and Pam 212 keratinocyte line both expressed IL-7 mRNA constitutively, as demonstrated by reverse transcription-polymerase chain reaction analyses. The production of IL-7 by mouse keratinocytes was also confirmed; Pam 212 culture supernatants supported DETC proliferation, and this activity was diminished by 50% with added anti-IL-7 antibodies. These results indicate that keratinocytes produce IL-7 in biologically relevant amounts, which, in turn, serve to promote the survival and growth of DETC. IL-7-mediated communication between epithelial cells and gamma delta T cells may represent one mechanism to sustain the indefinite residence of gamma delta T cells in epithelial tissues of mice.

Keratinocyte-derived IL-7 serves as a growth factor for dendritic epidermal T cells in mice

Dendritic epidermal T cells (DETC) are CD3+, CD45+, CD4-, CD8-, TCR-V gamma 3/V delta 1+ T lymphocytes that reside in symbiosis with keratinocytes in mouse epidermis. To address mechanisms by which these cells survive and proliferate within the epidermal environment, we have tested the hypothesis that cytokines secreted by neighboring keratinocytes play relevant roles. The present study was conducted to determine whether keratinocytes produce biologically relevant amounts of IL-7, and, if so, to study its effects on DETC. The long term cultured DETC line, 7-17, and freshly isolated DETC exhibited dose- and time-dependent proliferative responses to rIL-7. These responses were blocked completely by anti-IL-7 antibodies, whereas anti-IL-2 had no effect, indicating that DETC respond to IL-7 by an IL-2-independent mechanism. Proliferative responses depended on the state of cell activation; DETC stimulated 2 to 5 days earlier with Con A proliferated optimally to added IL-7, whereas cells stimulated 10 days earlier did not proliferate. DETC that failed to proliferate responded to IL-7 by showing prolonged survival; cells maintained for 7 days with IL-7 alone retained their capacity to proliferate in response to Con A. Mouse epidermal cells and Pam 212 keratinocyte line both expressed IL-7 mRNA constitutively, as demonstrated by reverse transcription-polymerase chain reaction analyses. The production of IL-7 by mouse keratinocytes was also confirmed; Pam 212 culture supernatants supported DETC proliferation, and this activity was diminished by 50% with added anti-IL-7 antibodies. These results indicate that keratinocytes produce IL-7 in biologically relevant amounts, which, in turn, serve to promote the survival and growth of DETC. IL-7-mediated communication between epithelial cells and gamma delta T cells may represent one mechanism to sustain the indefinite residence of gamma delta T cells in epithelial tissues of mice.

Cloning and characterization of the 2B4 gene encoding a molecule associated with non-MHC-restricted killing mediated by activated natural killer cells and T cells

We have recently described a signal transducing molecule, 2B4, expressed on all NK and T cells that mediate non-MHC-restricted killing. The gene encoding this molecule was cloned and its nucleotide sequence determined. The encoded protein of 398 amino acids has a leader peptide of 18 amino acids and a transmembrane region of 24 amino acids. The predicted protein has eight N-linked glycosylation sites, suggesting that it is highly glycosylated. Comparison of 2B4 with sequences in the databanks indicates that 2B4 is a member of Ig supergene family, and it shows homology to murine and rat CD48 and human LFA-3. Northern blot analysis has shown at least three transcripts for 2B4 in adherent lymphokine-activated killer cells of several mouse strains and TCR-gamma/delta dendritic epidermal T cell lines but not in allospecific T cell clones. These three mRNA are the products of differential splicing of heterogeneous nuclear RNA. Southern blot analysis of genomic DNA from several mouse strains revealed that 2B4 belongs to a family of closely related genes. The 2B4 gene has been mapped to mouse chromosome 1 by analysis of 2B4 expression in recombinant inbred mouse strains.

Cloning and characterization of the 2B4 gene encoding a molecule associated with non-MHC-restricted killing mediated by activated natural killer cells and T cells

We have recently described a signal transducing molecule, 2B4, expressed on all NK and T cells that mediate non-MHC-restricted killing. The gene encoding this molecule was cloned and its nucleotide sequence determined. The encoded protein of 398 amino acids has a leader peptide of 18 amino acids and a transmembrane region of 24 amino acids. The predicted protein has eight N-linked glycosylation sites, suggesting that it is highly glycosylated. Comparison of 2B4 with sequences in the databanks indicates that 2B4 is a member of Ig supergene family, and it shows homology to murine and rat CD48 and human LFA-3. Northern blot analysis has shown at least three transcripts for 2B4 in adherent lymphokine-activated killer cells of several mouse strains and TCR-gamma/delta dendritic epidermal T cell lines but not in allospecific T cell clones. These three mRNA are the products of differential splicing of heterogeneous nuclear RNA. Southern blot analysis of genomic DNA from several mouse strains revealed that 2B4 belongs to a family of closely related genes. The 2B4 gene has been mapped to mouse chromosome 1 by analysis of 2B4 expression in recombinant inbred mouse strains.

Profiles of cytokine mRNA expressed by dendritic epidermal T cells in mice

The epidermis of mice contains, in addition to Langerhans cells, a second dendritic population that is Thy-1+/CD3+/CD4-/CD8-/T-cell receptor-V gamma 3/V delta 1+. These dendritic epidermal T cells (DETC) are now thought to comprise one element in the family of epithelial tissue-resident gamma delta T cells. In the present study, DETCs were examined for their expression of mRNA for cytokines, using a reverse transcription-polymerase chain reaction. Freshly isolated Thy-1+ epidermal cells constitutively expressed mRNA for gamma-interferon, but not IL-2. Within 24 h after stimulation with Con A, these cells then expressed mRNA for gamma-interferon and IL-2, but not IL-4. The rapid onset of expression of mRNA for IL-2 occurred exclusively within the Thy-1+ population, and in a Con A-dependent fashion. When freshly isolated epidermal cells were first stimulated with Con A and then expanded in bulk with rIL-2 for 20-24 d, cells expressing IL-4 mRNA then emerged, upon secondary stimulation with Con A. These "short-term" DETC lines also expressed mRNA for IL-2, interferon-gamma, IL-1 alpha, IL-3, IL-6, IL-7, tumor necrosis factor alpha and beta, and granulocyte macrophage-colony stimulating factor. Interestingly, mRNA for IL-4 and IL-6 was no longer detected in long-term (> 1 year) DETC lines 7-17 and 12-12. In addition, one line (7-17) maintained IL-3 mRNA expression, whereas another (12-12) had lost this capacity. These results emphasize the concept that, as resident cells in epidermis, DETCs exhibit several different immunorelevant activities, and the heterogeneity in cytokine mRNA profiles suggests that DETCs may divide into functional subsets.

Reciprocal cytokine-mediated cellular interactions in mouse epidermis: promotion of gamma delta T-cell growth by IL-7 and TNF alpha and inhibition of keratinocyte growth by gamma IFN

A unique subset of gamma delta T cells, termed dendritic epidermal T cells (DETC), resides in symbiosis with keratinocytes in mouse epidermis. We have shown previously that interleukin 7 (IL-7) which is produced by keratinocytes, promotes growth and prevents apoptosis in DETC. To extend this observation, we examined 12 cytokines, each of which is expressed by epidermal cells at mRNA and/or protein levels, for their capacities to modulate the growth of DETC. Cytokines examined included IL-1 alpha, IL-2, IL-3, IL-4, IL-6, IL-7, IL-8, IL-10, tumor necrosis factor-alpha (TNF alpha), interferon-gamma (IFN gamma), granulocyte/macrophage-colony stimulating factor (GM-CSF), and macrophage inflammatory protein-1 alpha (MIP-1 alpha). When tested individually, IL-2 and IL-7 promoted maximal growth of the long-term cultured DETC line 7-17. When tested in combinations, synergistic growth-promoting effects were seen with IL-2 and IL-4 or IL-7, and with IL-7 and IL-4 or TNF alpha. Dose-response experiments demonstrated that TNF alpha, which is produced by keratinocytes, enhances IL-7-induced DETC proliferation, but inhibits IL-2-induced proliferation. The mouse keratinocyte-derived cell line Pam 212 was used to test these cytokines for their capacities to regulate keratinocyte growth. Only gamma IFN, which is produced by DETC, inhibited proliferation in a dose-dependent fashion. These results illustrate three reciprocal pathways by which epidermal cytokines regulate the growth of epidermal cells: 1) a paracrine mechanism by which keratinocyte-derived cytokines (e.g., IL-7 and TNF alpha) promote the growth of DETC, 2) an autocrine mechanism by which DETC-derived cytokines (e.g., IL-2 and IL-4) support their own growth, and 3) a reciprocal pathway in which a cytokine produced by resident epidermal leukocytes (e.g., gamma IFN) modulates the growth of keratinocytes.

Vasoactive intestinal peptide (VIP) causes memory impairment in passive avoidance responding of the rat

Our previous studies demonstrated that CCK-8 and its analog, cerulein (CER), have a potent preventive action on experimental amnesia, and that VIP has reciprocal action against CCK-8 and CER. Since VIP has been reported to cause amnesia, we carried out the present experiments to confirm this action and to examine the preventive effect of CER on VIP-induced amnesia. In the passive avoidance response, central administration, but not peripheral injection, of VIP caused amnesia; the effective portion of the molecule was found to be located in the N-terminus amino acid sequence. Secretin and PACAP, which have similar molecular structures to that of VIP, had no amnestic action. Preadministration of CER prevented VIP-induced memory deficit. The VIP antagonists did not affect amnesia induced by electroconvulsive shock and scopolamine. It was concluded that CER prevents VIP-induced memory deficit in the passive avoidance response of the rat.

Influence of chronic intracerebroventricular infusion of vasoactive intestinal peptide (VIP) on memory processes in Morris water pool test in the rat

In our previous study, bolus injection of VIP into the lateral cerebral ventricle, at nonphysiological high doses, has been shown to produce amnesia. Accordingly, in the present study, VIP was infused chronically into the cerebral ventricle of the rat at a rate of 10 ng per day for 2 weeks. During the infusion period, the animals were subjected to the Morris water pool test. The VIP infusion caused an apparent impairment of memory, particularly in the acquisition of new information; VIP(1-12) also caused similar impairment, but to a lesser extent. The VIP antagonists did not affect the performance of learned tasks. However, cerulein treatment prevented the VIP-induced memory impairment.

Killing of skin-derived tumor cells by mouse dendritic epidermal T-cells

Dendritic epidermal T-cells (DETC) are a unique population of T-cells that reside normally in mouse epidermis and express a gamma delta T-cell receptor. We have reported previously that DETC acquire in culture the capacity to lyse the YAC-1 lymphoma, a conventional target for natural killer cells. The aim of the present study was to characterize this cytotoxic potential, using a spectrum of skin-derived mouse tumors. Cytotoxicity was measured by a 51Cr release assay and by the visual assessment of target cell lysis. Long-term DETC lines, established from CBA, AKR, and BALB/c mice by mitogenic stimulation and repeated feeding with interleukin 2 (5 units/ml), were used as effectors. Skin-derived tumor targets included 5 melanoma lines and the transformed keratinocyte line Pam 212. Each DETC line lysed skin-derived tumors as well as YAC-1 targets effectively in the 18-h 51Cr release assay, and target lysis occurred in a non-major histocompatibility complex-restricted manner. By contrast, freshly isolated spleen cells lysed YAC-1 but not skin tumor targets. Moreover, confluent monolayers of melanoma or Pam 212 targets were disrupted completely by added DETC lines but not by spleen cells. The cytolytic activity of DETC appeared to be specific for tumor cells, since normal mouse keratinocyte monolayers remained intact under the same conditions. Finally, DETC freshly isolated from skin failed to exhibit significant cytotoxicity but acquired this capacity 10-14 days after mitogenic stimulation and feeding with interleukin 2 (5 units/ml). We conclude that DETC possess the potential to recognize, bind, and lyse tumor cells that originate in skin.

Mouse dendritic epidermal T cells exhibit chemotactic migration toward PAM 212 keratinocyte culture supernatants

Dendritic epidermal T cells (DETCs) are Thy-1+, CD45+, CD3+, CD4-, CD8-, and T-cell receptor-V gamma 3/V delta 1+ leukocytes that reside normally in adult mouse skin. We have demonstrated previously that keratinocytes serve as adhesion substrates for DETCs, and that interleukin 7 (IL-7), which is produced by keratinocytes, serves as a growth factor for DETCs. The present study was conducted to address the mechanisms by which DETCs migrate into the epidermis, reasoning that keratinocytes may also be a source of chemotactic activity. Short-term DETC lines were 35S-labeled and tested for migration toward Pam 212 keratinocyte culture supernatants using a modified Boyden chamber method; cell movement from upper chambers toward test samples in lower chambers was traced by counting radioactivity. DETC displayed rapid (within 60 min) and marked (> 50%) migration toward keratinocyte supernatants. The majority of cells that had migrated into keratinocyte supernatants expressed the V gamma 3 T-cell receptor, thus verifying that the migrating cells were DETCs. Addition of keratinocyte supernatants to the upper chambers completely blocked migration, suggesting its chemotactic nature. By contrast, no DETC migration was observed toward 3T3 fibroblast supernatants. Chemotactic activities were 1) produced by Pam 212 cells even in the absence of serum; 2) greater than 12 kD in size; 3) heat and pH labile; 4) trypsin sensitive; and 5) precipitated by 60-100% ammonium sulfate. Several cytokines (e.g., IL-1 alpha and IL-8) failed to mediate DETC migration when added to the lower chambers. Likewise, the same cytokines, when added to the upper chambers, failed to inhibit DETC migration toward Pam 212 supernatants. These results support our hypothesis that keratinocytes facilitate the residence of DETC in epidermis by secreting unique chemotactic factors, by providing adhesion substrates, and by elaborating specific growth factors.

Tau protein kinase I is essential for amyloid beta-protein-induced neurotoxicity

Pathological changes of Alzheimer disease are characterized by cerebral cortical atrophy as a result of degeneration and loss of neurons. Typical histological lesions include numerous senile plaques composed of deposits of amyloid beta-protein and neurofibrillary tangles consisting predominantly of ubiquitin and highly phosphorylated tau proteins. Previously, tau protein kinase I (TPK I) was purified and its cDNA was cloned. To examine the biological role of this enzyme in neurons, we have studied the induction of its kinase activity in primary cultures of embryonic rat hippocampal neurons. Treatment of cultures with amyloid beta-protein significantly increased TPK I activity and induced the appearance of tau proteins recognized by the Alz-50 monoclonal antibody. In addition, though amyloid beta-protein was neurotoxic, either cycloheximide or actinomycin D prevented neuronal death. Death was also prevented by TPK I antisense oligonucleotides but not by sense oligonucleotides. These observations suggest that rat hippocampal neurons undergo programmed cell death in response to amyloid beta-protein and that TPK I is a key enzyme in this process.

In vivo activation of mouse dendritic epidermal T cells in sites of contact dermatitis

Adult mouse epidermis contains a population of dendritic, Thy-1+, CD3+, CD4-, CD8- and T cell receptor (TcR) V gamma 3/V delta 1+ leukocytes termed dendritic epidermal T cells (DETC). DETC isolated from skin and placed into culture will proliferative vigorously in response to T cell mitogens and T cell growth factors. In the present study, we examined whether DETC can be activated in situ by modulating their epidermal environment. Ear skin of CBA mice was painted with the chemical irritant, croton oil, and the epidermal cells (EC) isolated from such sites were then tested for proliferative responses to exogenous interleukin-2 (IL-2), in the absence of added mitogens. Cells from croton oil-treated skin showed marked IL-2 responsiveness, whereas cells from phosphate-buffered saline-treated skin failed to proliferate. IL-2 responses were seen as early as 2 days after croton oil treatment and peaked between days 5 and 10. gamma delta TcR-bearing cells, most likely resident DETC, were the major population to respond to IL-2, since depletion of gamma delta TcR+ cells, but not alpha beta TcR+ cells, abolished that responsiveness, and since gamma delta TcR+ cell numbers increased markedly in the cultures that contained added IL-2. These results indicate that DETC in normal skin, which are at a state of rest, may be activated when their residential epidermal environment is disrupted externally. This process of DETC activation may be a critical step in the maturation of DETC into effector leukocytes in vivo.

Regulation of muscarinic stimulation of norepinephrine release and PI hydrolysis during cell growth in PC12 cells

We have studied the relationships of cell growth to muscarinic stimulation of norepinephrine release and phosphoinositide hydrolysis in the rat pheochromocytoma PC12 cells. The ability of these cells to release norepinephrine in response to muscarinic agonists was maximal during the early phase of exponential growth, and then rapidly decreased to undetectable levels as the cells approached stationary phase. In contrast, muscarinic stimulation of phosphoinositide hydrolysis was low in the early exponential phase of growth, increased to a maximum during late exponential growth and then dramatically dropped in the stationary phase. The number of muscarinic receptors, as measured by antagonist-binding studies, also varied during cell growth with maximal levels at days 2 and 8, corresponding to the maxima in muscarinic-stimulated norepinephrine release and phosphoinositide hydrolysis, respectively.

Signal transduction via phosphorylated adhesion molecule, LFA-1 beta (CD18), is increased by culture of natural killer cells with IL-2 in the generation of lymphokine-activated killer cells

It is well known that IL-2 stimulates natural killer (NK) cells to express lymphokine activated killer (LAK) activity and that this stimulation prompts the acquisition of the ability to lyse previously insensitive target cells. The possible role of adhesion molecules in the IL-2 activation process was probed by focussing on a lymphocyte function-associated antigen (LFA)-1-dependent model system. A mAb to the LFA-1 beta chain abrogated LAK activity, but only moderately suppressed NK activity, suggesting a differential role for LFA-1 beta in LAK compared with NK mediated lysis. Orthophosphate labeling demonstrated that the LFA-1 beta chain was strongly phosphorylated in LAK but not NK cells; in contrast, the alpha chain was phosphorylated similarly in both effector cell types. At least a portion of the phosphorylation of the beta chain was on tyrosine residues, as shown by Western blotting with anti-phosphotyrosine antibody of LFA-1 beta immunoprecipitates. Crosslinking of the LFA-1 beta chain with plastic-adhered antibody stimulated Ca(2+)-dependent release of cytoplasmic lytic granules and induced phosphatidyl inositol turnover in LAK but not NK cells. We conclude that the IL-2-induced phosphorylation of the beta chain of the LFA-1 adhesion molecule in LAK cells and associated alteration in signal transduction may be important in the stimulation of LAK cell activity in NK cells.

Dendritic epidermal T cells: lessons from mice for humans

Dendritic epidermal T cells (DETC) in mice form part of a primitive system of epithelial-resident T cells characterized by the expression of gamma delta T-cell receptors (TCR). Critical attributes that characterize DETC include their highly restricted T-cell receptor gene utilization, proliferation and maturation within epidermis, a capacity to kill relevant skin-derived tumor targets, and the ability to modulate immune responses that are initiated and expressed in skin. Contemporary knowledge suggests that DETC and the related skin-directed gamma delta T cells found in humans play important roles in maintaining the immunologic integrity of skin.

Cytokine expression by epidermal cell subpopulations

Epidermal cells (EC) are a rich source of cytokines that can regulate the function of cells in skin and in other tissues. To organize the array of data pertaining to cytokine expression by EC subpopulations, we have tabulated such data according to cell source, state of cell activation, and type of assay employed. This information forms a background for our own studies, in which reverse transcriptase-polymerase chain reaction (RT-PCR) was used to show that Langerhans cells (LC) are the principal source of mRNA for interleukin 1 beta and macrophage inflammatory protein-1 alpha (MIP-1 alpha) among unstimulated mouse EC.

Langerhans cells are the major source of mRNA for IL-1 beta and MIP-1 alpha among unstimulated mouse epidermal cells

Immunocompetent cells of the epidermis can interact by the elaboration and recognition of cytokines. Although much new information has been reported concerning the cytokines secreted by keratinocytes, little is known about cytokines derived from Langerhans cells (LC). To address this deficiency, we examined cytokine mRNA profiles in different epidermal preparations from BALB/c mice, taking advantage of the sensitive technique of polymerase chain reaction (PCR), after reverse transcription of mRNA. In assays of epidermal sheets separated from dermis by ammonium thiocyanate, mRNA for IL-1 alpha, IL-1 beta, IL-6, IL-7, tumor necrosis factor alpha (TNF alpha), TNF beta, granulocyte macrophage/colony-stimulating factor (GM-CSF), and macrophage inflammatory protein-1 alpha (MIP-1 alpha) were unequivocally present. By contrast, faint bands were detected for IL-4, IL-5, and interferon gamma (IFN gamma), and no PCR signal was detected for IL-2. Importantly, assays of epidermal cells (EC) dissociated with trypsin revealed similar mRNA profiles. To determine the effects of cell isolation, fluorescence-activated cell sorter (FACS)-purified Ia- EC were first analyzed; all of the previously cited cytokine mRNA were present except for IL-1 beta and MIP-1 alpha. EC depleted of LC by a second technique, lysis using anti-Ia monoclonal antibody and complement, revealed similar profiles, with substantially reduced PCR signals for IL-1 beta and MIP-1 alpha. Finally, FACS-purified LC (Ia+ EC) clearly expressed IL-1 beta and MIP-1 alpha mRNA, a finding that was verified by Southern blotting using internal oligo probes. We conclude that these cell-isolation procedures did not produce substantial alterations in basal mRNA profiles and that LC are the principal source of mRNA for IL-1 beta and MIP-1 alpha among unstimulated EC in mice.

Protective effect of cerulein on memory impairment induced by protein synthesis inhibitors in rats

Previous studies have demonstrated that NMDA receptor antagonists and protein kinase C inhibitors induced marked memory impairment in rats, but that peripherally administered cerulein (CER) prevented these effects. In the present study, the effect of subcutaneously administered CER on amnesia induced by protein synthesis inhibitors was examined in passive and active avoidance responses and in the Morris water maze test. Intraperitoneal injection of the inhibitors produced marked memory impairment, but the effect was abolished by combined administration with CER. The effective dose of subcutaneously injected CER was, on a molar basis, three thousand- and six thousandfold less than the dose of anisomycin, and two hundred eighty- and three thousandfold less than the dose of puromycin in the passive and active avoidance response experiments, respectively. Similarly, in the Morris water maze test, behavioral disturbances produced by the protein synthesis inhibitors were abolished by CER. These results indicate the effectiveness of CER in preventing memory impairment induced by protein synthesis inhibitors.

Determination of the action spectrum for UV-induced plasminogen activator synthesis in mouse keratinocytes in vitro

Mouse epidermal keratinocyte-derived Pam 212 cells were irradiated with UV light, and the culture media were examined for plasminogen activator (PA) activity by measuring the capacity to convert exogenous plasminogen into plasmin. Exposure of cells to a broad spectrum of light in the UVB range induced a significant elevation of PA activity at 16 h after irradiation. A dose-response study revealed that a maximal enhancement, 15-fold higher than non-irradiated controls, was induced at a sublethal UVB dose of 100 J/m2, which significantly inhibited cell proliferation without affecting cell viability. Addition of 5 micrograms/ml of cycloheximide lowered the UV-induced elevation of PA activity, suggesting that protein synthesis is required for this phenomenon. Action spectra for PA synthesis were obtained by irradiating cells with monochromatic light ranging from 250 to 360 mm, and the data demonstrated that the action spectrum was 250-320 nm in length with a peak between 260 and 280 nm. The results suggest that UV exposure is an important physiological trigger for modulating PA synthesis in the epidermis.

Folate receptor allows cells to grow in low concentrations of 5-methyltetrahydrofolate

The folate receptor mediates the uptake of 5-methyltetrahydrofolate in certain cultured cells by a process called potocytosis. When these cells are grown in physiological concentrations of folate, the receptor increases the efficiency of vitamin uptake by 30-fold. We now show that PAM 212 cells, a mouse keratinocyte cell line, are unable to grow in 1 nM 5-methyltetrahydrofolate unless they express a functional folate receptor. These results suggest that under certain conditions, tissue cells in the body may depend on the folate receptor to obtain enough 5-methyltetrahydrofolate for growth.

Clinical analysis of cancer patients with bacteremia for the past ten years (1982-1991)

A trend in bacteremia associated with malignancies was studied in 159 cancer patients (pts) over the past ten years (1982-1991) in our university hospital. The proportion of female, aged persons and patients from the Int Med Dept had a tendency to increase in the later 5 years compared to the former 5 years. There was no significant change in proportion among G (+), G (-) and fungus groups. However, St. aureus has a tendency to increase among G (+) bacteria and Ps. aeruginosa among G (-) bacteria. The clinical features of the cancer patients with bacteremia were different depending on the types of organisms or kinds of underlying malignancies.

Pretreatment with caerulein protects against memory impairment induced by protein kinase C inhibitors in the rat

The effect of subcutaneously injected caerulein (CER) on memory impairment induced by protein kinase C (PKC) inhibitors, H-7 and melittin, was examined in rats. Intracerebroventricular injection of PKC inhibitors caused marked memory impairment in one-trial passive avoidance response and Morris water tank tasks. However, when rats were pretreated with CER at a subcutaneous dose of 1 microgram/kg 3 hours before the training trials, the reduced latency of the passive avoidance response was significantly increased, and in the Morris water pool tasks the memory deficit induced by PKC inhibitors completely disappeared. These results indicate that CER can offer protection against the effect of PKC inhibitors at least from the viewpoint of the memory processes.

Genomic, phenotypic, and functional analyses of T cells in patients with psoriasis undergoing systemic cyclosporin A treatment

Recent studies have demonstrated that cyclosporin A (CyA) exerts a beneficial effect on psoriasis. It remains unclear, however, whether T-cell immune responses are definitely impaired in psoriasis and whether the anti-psoriatic effect of CyA is mediated by interference with T-cell activation. To study these questions, 20 patients with severe psoriasis were treated with oral CyA (5 mg/kg/d) for 12 weeks and examined for several phenotypic and functional properties of peripheral blood T cells before and after therapy. The analyses included CD3, CD4, and CD8 phenotypes, IL-2 production and IL-2 receptor expression following Con A stimulation, proliferative responses to PHA, and in vivo responsiveness to a foreign antigen, PPD. When the values of patients before therapy and healthy individuals were compared, no statistically significant differences were detected in any of these analyses. Furthermore, none of these T-cell properties were changed after 12 weeks of treatment. To assess possible minor mutations in T-cell-related genes in psoriasis, the T-cell receptor beta-chain locus was analyzed by Southern hybridization. With a cDNA probe for C beta 1, a polymorphic fragment of congruent to 9 kb was detected in Eco RI digests in one of 20 patients and in four of 10 healthy individuals examined. No polymorphism was detected in Bam HI digests in any individual. These results fail to support the hypothesis that a general or "systemic" alteration in T-cell immunity plays a central role in the pathogenesis of psoriasis and in the action of CyA against this skin disorder.

Balloon dilatation for entire urethral stricture

Two patients with entire urethral stricture were treated with balloon dilatation of the whole urethra using a torpedo-type dilatation balloon with satisfactory results. Postdilatation urethrograms revealed that the lumen of the urethra was of satisfactory width in both cases, and the patients are now voiding normally. There has been no complication requiring therapy. These successful results suggest that this technique is a good alternative treatment for entire urethral stricture, and can replace conventional dilatation.

Allergic contact and photocontact dermatitis due to psoralens in patients with psoriasis treated with topical PUVA

The incidence and clinical features of allergic contact and/or photocontact dermatitis due to psoralens were examined in 371 patients with psoriasis treated with topical PUVA. The psoralen derivatives used in the study were 8-methoxypsoralen (8MOP), 3-carbethoxypsoralen (3CPs), 4,6,4'-trimethylangelicin (TMA) and 7-methyl pyridopsoralen (MPP). Of 371 patients treated with 8MOP, three (0.8%) developed an acute dermatitis in the PUVA-treated areas. This incidence was significantly lower (P less than 0.01) than that for 3CPs (four of 10 patients) or that for TMA (six of 17 patients). None of the seven patients receiving MPP on PUVA had a reaction. It was confirmed that these dermatitis reactions were due to contact and/or photocontact allergy to psoralens by several methods that include patch and photopatch tests, photopatch test mapping, determination of the minimal erythema dose (MED) and immunohistochemistry.

Effect of caerulein on decreased latency of passive avoidance response in rats treated with NMDA receptor antagonists

The effect of subcutaneous injection of caerulein on memory impairment induced by intracerebroventricular administration of NMDA receptor antagonists was examined in the passive avoidance response of the rat. When rats were treated with AP5, AP7, CPP or MK-801, the retention latencies decreased markedly. However, in rats that received caerulein immediately after the training trials, the latency increased to some extent. Pretreatment with caerulein and subsequent injection of the competitive NMDA receptor antagonists AP5, AP7 and CPP caused a more apparent increase in the latency. The noncompetitive NMDA receptor antagonist MK-801 was not affected by pretreatment with caerulein. The difference might be, at least in part, due to the sites of action of these NMDA receptor antagonists.

Cutaneous carcinoma and 8-methoxypsoralen and ultraviolet A (PUVA) lentigines in Japanese patients with psoriasis treated with topical PUVA: a follow-up study of 214 patients

A total of 214 Japanese patients with psoriasis, under treatment with topical 8-methoxypsoralen and ultraviolet A (PUVA), were examined for malignant skin tumors and pigmented lesions during a follow-up period of up to 17 years (mean 5.8 years). One patient had developed multiple superficial basal cell carcinomas, and the remaining 213 patients had neither cutaneous carcinomas nor actinic keratoses. PUVA lentigines were seen in 89 patients (42%) and the incidence of lentigines increased as the number of PUVA treatments and the cumulative UVA dose increased. Melanocytic atypia was not observed histologically in 24 pigmented lesions examined. This report suggests that this topical PUVA regimen may not be highly carcinogenic in the Asian population.

Treatment of a case of mycosis fungoides and one of parapsoriasis en plaque with topical PUVA using a monofunctional furocoumarin derivative, 4,6,4'-trimethylangelicin

A case of plaque stage mycosis fungoides and one of parapsoriasis en plaque were treated with topical PUVA therapy using a monofunctional furocoumarin derivative, 4,6,4'-trimethylangelicin (TMA). Both patients showed complete clearance of eruptions within 16 treatments. The therapeutic effectiveness of TMA was confirmed by the fact that those eruptions exposed to UVA alone, without TMA application, showed slower and less significant improvement. Histologically, dermal infiltrates of mycosis cells and associated epidermotrophism disappeared almost completely in response to TMA PUVA. No side effects or changes in values in laboratory examinations were observed during treatment.

Treatment of PUVA- and retinoid-PUVA-resistant severe psoriasis with systemic cyclosporin A

Twenty patients with severe psoriasis were treated with the oral administration of 5 mg/kg/day of cyclosporin A (CyA) for 12 weeks. These patients had either failed to respond to or had become unresponsive to conventional treatments including PUVA, UVB, or combinations of etretinate and PUVA or UVB. Complete clearance and marked improvement were observed in 12 (60%) and 4 patients (20%), respectively. The average score of the Psoriasis Area and Severity Index (PASI) was 26.2 before treatment, decreasing to 18.3 in 2 weeks, 8.2 in 6 weeks, and 5.1 in 12 weeks of CyA treatment. There was a tendency for patients with lower blood levels of CyA to show smaller decreases in their PASI scores. In four patients who received skin biopsies, histological improvement was noted within 10 days of treatment; epidermal thickness had decreased by 32%, intraepidermal mitoses by 66%, and parakeratosis had disappeared almost completely. No clinical side effects or alterations in laboratory values were observed that required cessation of CyA. Exacerbations of psoriasis occurred in 11 of 16 patients within 6 weeks after stopping treatment. These results suggest that CyA could be the first choice of treatment for resistant severe psoriasis.

Human seminal plasma Zn-alpha 2-glycoprotein: its purification and properties as compared with human plasma Zn-alpha 2-glycoprotein

On the basis of the datum that the level of Zn-alpha 2-glycoprotein (Zn alpha 2gp) in human seminal plasma was about 6-times higher than that in adult serum, Zn alpha 2gp was purified from fresh human seminal plasma approx. 70-fold with 60% yield over seminal plasma by DEAE-Sephacel, Zn-chelate Sepharose 4B and DEAE-5PW column chromatographies. The molecular weight of seminal plasma Zn alpha 2gp was 50,000 on Superose column chromatography, and 40,500 and 41,500 on SDS-polyacrylamide gel electrophoresis in the absence and presence of beta-mercaptoethanol, respectively. Plasma Zn alpha 2gp is a glycoprotein, while the protein from seminal plasma does not contain carbohydrate. The amino acid sequence of the first 17 residues of seminal plasma Zn alpha 2gp was Glu-Asn-Gln-Asp-Gly-Asn-Tyr-Ser-Leu-Thr-Tyr-Ile-Tyr-Thr-Gly-Leu-Ser. This sequence was completely identical with the amino acid residues from Glu-2 to Ser-18 in the N-terminal amino acid sequence of plasma Zn alpha 2gp. These data suggest that both Zn alpha 2gps in plasma and seminal plasma may be expressed from one gene, but their posttranslational modifications are different.

A survey regarding the disclosure of the diagnosis of cancer in Toyama Prefecture, Japan

A survey regarding the revelation of the diagnosis of cancer to patients was conducted on 116 medical doctors (MD), 206 paramedical personnel (PP) and 789 lay persons (LP) in June 1989 in Toyama prefecture, Japan. When asked in the case that their parents or spouse had cancer, only 29.8% of all respondents answered that they would reveal the diagnosis of cancer to their family member. On the contrary, if they themselves had cancer, 56.3% of all respondents answered that they wished the diagnosis to be revealed, and 77.4% of these answered that they wished to be informed of the cancer diagnosis by the doctor in charge. They wanted to know the details of their condition from their medical doctor, and thought that they could receive this knowledge calmly. Thirty-one percent (34/108) of the doctors questioned reveal the diagnosis of cancer to their patients and 79.4% of these answered that they felt that telling the true diagnosis was good. A serious responsibility for the medical doctor was indicated.