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Treatment of rat heart grafts with PUVA, the combination of the photosensitizer 8-methoxypsoralen and longwave ultraviolet light, leads to a prolonged transplant survival in allogeneic recipients. A PUVA treatment of the recipient rats, performed for 7 consecutive days after transplantation, prolonged graft survival even more effectively. This may be due to the systemic immunomodulatory effects of PUVA in the recipient. One of the mediators is urocanic acid, which is transformed by ultraviolet light in the skin from its trans- to the cis-isomer, which, in turn, acts as a mediator on the immune system. An injection of cisurocanic acid into graft recipients for 7 consecutive days after transplantation resulted in prolonged graft survival; in 40% of the rats, permanent graft acceptance was observed. The significance of these results for clinical organ transplantation is discussed.

8 patients with confirmed psoriatic arthritis were treated with splenopentin for 12 months. A relief of joint pain could be detected under this treatment both after 6 weeks (improvement of the Ritchie-indices: 44%) and after 12 months (improvement: 28%). In contrast to this, X-ray investigations show a worsening of the disease after 12 months. Therefore we conclude that splenopentin alone is not a sufficient therapeutic drug in patients suffering from psoriatic arthritis.

Using mononuclear cells (MNC) of patients suffering from psoriasis for production of colony-stimulating factors (CSF) an abnormal colony formation in bone marrow of healthy volunteers was detected (colony-forming assay): Number of colonies per 10(5) bone marrow cells after cultivation with 10(6) MNC of patients suffering from psoriasis vulgaris: 65 +/- 14 (n = 8); psoriasis arthropathica: 63 +/- 11 (n = 8). Control values (10(5) bone marrow cells plus 10(6) MNC of healthy donors): 116 +/- 23 (n = 10). Statistical differences: psoriasis vulgaris: p less than 0.001; psoriasis arthropathica: p less than 0.001. The mechanisms responsible for these abnormalities in hematopoiesis are still unknown. They may be of pathogenic significance in psoriasis.

In the last years a new therapy of psoriasis was developed, which consists in a treatment with salt solutions, resembling the water of the Dead Sea, and ultraviolet light (Tomesa-therapy). We studied the influence of the used salt on ATPase positive epidermal Langerhans cells in murine ear skin. An irreversible partial reduction of the Langerhans cell ATPase was found after salt treatment of separated epidermis or of full skin preparations. These results may have implications for the optimization and broader application of this therapy.

In 1981 a new splenic hormone was described by Audhya et al. (Biochemistry, 20, 6195-6200, 1981). At first designated as thymopoietin III, the complete amino acid sequence had been described as splenin in 1984. For the pentapeptide corresponding to amino acids 32-36 of splenin was shown to be active in immunological systems. The synthetic pentapeptide splenopentin (DAc-SP-5) and the sequence 32-36 of splenin are identical. In this study the recovery of immunocompetence in mice following sublethal irradiation is shown to be enhanced by DAc-SP-5. The treatment effects of DAc-SP-5 were verified by splenic plaque-forming response to a T-cell dependent antigen and in the hematopoietic colony-forming assay. These effects were associated with an accelerated recovery of leukocyte counts in peripheral blood and spleen without significant changes in the relation between leukocyte and lymphocyte subpopulations. Furthermore, in comparison to control animals DAc-SP-5 treated mice showed in the first weeks postexposure a significantly higher number of bone marrow derived cells as well as granulocyte-macrophage and macrophage colony-forming cells (GM-CFC and M-CFC). Therefore, DAc-SP-5 may be a useful substance for treating secondary forms of bone marrow depression.

Splenopentin (SP-5: Arg-Lys-Glu-Val-Tyr), a pentapeptide corresponding to the residues 32-36 of the splenic hormone splenin, increases dose-dependently the number of bone marrow colonies (M and GM colonies). Therefore, we tested the stimulatory effect of SP-5 on the recruitment of epidermal Langerhans cells in skin deprived of these cells. A high dose of cyclophosphamide or dexamethasone led to a drastic decrease of LC density in murine skin with slow and incomplete restoration. SP-5 accelerated Langerhans cell recruitment and led to pretreatment levels of Langerhans cell density in the skin. These results indicate that SP-5 may possibly be used to treat disorders (e.g., HIV infection) where impaired Langerhans cell density and function can lead to secondary cutaneous infections.

A PUVA treatment of the recipients of murine tail skin grafts led to a significant prolongation of transplant survival. A possible mechanism of the systemic immunomodulatory effects of ultraviolet light in the organism is the transformation of urocanic acid in the skin from its trans- to the cis-isomer, which acts as a mediator on the immune system. A treatment of graft recipients with cis-, but not trans-urocanic acid also prolonged graft survival. The rejection of secondary grafts and the humoral immune response of mice to sheep erythrocytes were not influenced by cis-urocanic acid. These results implicate that cis-urocanic acid may be get use in clinical organ transplantation and dermatology.

An ointment, consisting of 100 micrograms hematoporphyrin derivative +5.0 ml dimethylsulfoxide +95.0 ml Unguentum Alcoholum lanae SR, was checked for both phototoxic and antipsoriatic efficacy. After topical application and irradiation with visible light or ultraviolet radiation, healthy skin showed delayed erythemas, whereas psoriasis plaques improved markedly.

A synthetic thymic pentapeptide was used for prestimulation of mouse lymphocytes in vivo. This pentapeptide (DAc- Glu3 -TP5) affected the cAMP and cGMP levels positively and decreased the 3H-thymidine incorporation in lymphocyte cultures significantly. In combination with Con A DAc- Glu3 -TP5 influenced the production of interferon. After in vivo pretreatment of adult hybrid mice with DAc- Glu3 -TP5 the mitogen-induced interferon production was 3 to 7 times higher than in controls. The interferon produced was immune interferon (IFN gamma) as determined by pH 2-sensitivity and lack of neutralization by mouse IFN beta-antibodies.

Interferon-like activity could be detected in the sera of nineteen psoriatic patients (interferon titres between 8 and 64 i.u./ml), whereas healthy controls were negative. Following PUVA treatment the interferon levels increased significantly (interferon titres between 32 and 128 i.u./ml). An enhanced interferon production could explain some of the immunological phenomena connected with PUVA treatment.

Sublethally irradiated AB/Bln mice (500 cGy) were treated with splenotritin (fragment 32-34 of the splenic hormone splenin) and tested for their capability of producing antibodies against target sheep red blood cells. In x-ray plus splenotritin treated mice antibody forming cells were found earlier and in a higher frequency than in mice treated with x-rays alone.

Early experiments had shown that splenopentin, the active part of the splenic hormone splenin, stimulates the differentiation of virgin B- and T-lymphocytes and significantly enhanced the reconstitution of immune reactions after immune suppression. The present study investigates the influence of splenopentin on the course of the graft-vs-host reaction (GVHR). The experimental model used were adult hybrid mice which received intravenously parental spleen cells. During the GVHR which has an chronical course in the strain combinations used a short stimulatory phase is followed by a long-lasting immunosuppression detected by antibody formation against sheep erythrocytes. Furthermore, the splenomegaly in the first weeks after spleen cell injection changed to a drastic decrease of the spleen weight up to strongly beyond normal values. Continuous treatment with splenopentin significantly prevented both symptoms of the GVHR: The suppression of the antibody formation was diminished widely, and no loss of spleen weight occurred. Furthermore, during the stimulatory phase anti-DNA-autoantibodies were produced in the untreated animals, while the splenopentin therapy prevented this reaction. During the further course of the experiment no increase of autoantibody production was detected later on.

B lymphocytes from patients suffering from systemic lupus erythematosus show increasing rates of spontaneous transformation in prolonged cultivation (144 hr). An additional B cell stimulation could be detected following the addition of sera from lupus erythematosus patients (isolated during the acute phase of disease) to the culture medium. In addition enriched mitogenic serum components from lupus sera increase the 3H-thymidine uptake of Brucella abortus primed B cells of healthy controls. The incorporation of 3H-thymidine with respect to the Brucella antigen concentration is described.

Immune complexes isolated from sera of psoriatic patients and healthy controls show an identical pattern in sodiumdodecylsulfate polyacrylamide gel electrophoresis. And so it seems to be unlikely that the increased provable serum immune complexes by psoriatics contain specific protein antigens.--Following to limited proteolysis of normal human epidermis, antibodies which solely are provable in sera of psoriatic patients could bind to proteolytic altered structures. For achieving a similar process in vivo, the following conditions are to be discussed: (1) an elevated concentration of certain autoantibodies in the sera of psoriatic patients and a temporary increased vessels permeability for antibodies, (2) the availability of structures in the epidermis of psoriatics with increased affintiy to certain antibodies. These structures may be produced by limited proteolysis or as a result of the disturbed differentiation of epidermal cells.

Serum immune complexes were estimated by a polyethylene glycol precipitation method in 51 patients with early syphilis. The immune complexes were increased in 41% of patients before treatment and decreased to normal limits in only 56% during treatment. The results of the specific antireponemal tests using dissolved immune complexes show that antibodies from the immune complexes are specific antibodies.

The influence of various immunoregulatory substances was studied in lymphocyte cultures derived from patients suffering from systemic lupus erythematosus (SLE) by using the model of spontaneous secretion of polyclonal immunoglobulin G (IgG)/immunoglobulin M (IgM) and anti-DNA autoantibodies. Compared with healthy donors, lymphocytes derived from patients with active SLE disease showed an elevated secretion of total IgG as well as anti-DNA-IgG in vitro, which was associated with an increase in the proportion of activated (HLA-class II +) T cells in their peripheral blood. Recombinant interferon-gamma increases the total IgG/IgM as well as anti-DNA-IgG/IgM secretion, which suggests that it has a possible role in the pathogenesis of SLE disease. Recombinant interleukin-2 and prostaglandin E2 normalize the high, spontaneous total IgG secretion, but elevate anti-DNA-IgG/IgM secretion. These results suggest that autoreactive B-cell clones are regulated differently in SLE patients. Cyclosporine inhibits total IgG/IgM secretion in all patients and anti-DNA-IgG/IgM secretion in six of eight patients. The possible therapeutic use of such immunomodulatory substances in SLE disease is discussed.

The wound-healing agent Dalargin, a hexapeptide and varios of its cleavage products were tested in a wound-healing model on the basis of granulation in rat. Three days after wounding (p.op.) an increase in granulation was observed at Dalargin concentrations of 10 micrograms/ml and 50 micrograms/ml. Seven days p.op. an increase was observed already at a Dalargin concentration of 5 micrograms/ml. The cleavage products of Dalargin had no stimulating effect on granulation. A histologic differentiation of the different cell parts in the granulation tissue led to an increased total number of cells. The concentration of 5 micrograms/ml induced both an increase in the number of endothelial cells and fibroblasts, the concentration of 50 micrograms/ml induced just an increase of the number of endothelial cells. The possible bases of the mode of operation are being discussed. The stimulating effect on wound healing as described could be confirmed by the results obtained in our animal experiments.

We studied the influence of the calcium transport inhibitor diltiazem on epidermal Langerhans cell-induced contact dermatitis against 1-chloro-2.4-dinitrobenzene (DNCB) in Balb/c mice. Diltiazem administered systemically was found to be able to decrease allergic reactions against DNCB. Twenty four hours post challenge animals treated with diltiazem demonstrated a 36% decreased ear swelling compared with non diltiazem-treated animals (p less than 0.001). From these results, we conclude that calcium is important in regulating epidermal Langerhans cell functions and in activating these cells.

The maturation effect of DA-SP5 on a spleen cell population depleted of immunocompetent, histami nereceptor-bearing lymphocytes was examined. Conjugates of histamine and the A-chain of the mistletoe lectin I killed in vitro these cells and abolished, as shown in a previous paper, their humoral and cellular capacity by around 90%. Sublethally irradiated mice were reconstituted with the remaining cells and treated with DA-SP5 (3 intraperitoneally injections of 10 micrograms DA-SP5 per week). The strong accelerating action of DA-SP5 on the restoration of the antibody response is interpreted as an effect of DA-SP5 on the maturation of B- and T-cells under in vivo conditions.

Products of lipid peroxidation (malonaldehyde, Schiff-bases) were detected in human skin. These products were increased after UV-light exposition, on chronically sun-exposed areas as well as with advancing age. Malonaldehyde cross linked epidermal glucose-6-phosphate-dehydrogenase and diminished their activity.

A survey is given about the so far known mode of action and the therapeutic application of the following agents with immunostimulatory effects: Interleukin-2, Interferon-gamma, Tumor necrosis factor, Thymosin alpha 1, Thymopentin, Splenopentin, Thymulin, Thymostimulin, Muramyl dipeptide, Bestatin, Tuftsin and Levamisole. The treatment of patients suffering from immunodeficiency disorders and cancer with such agents seems to be possible in the near future.

Thymosin (thymus fraction 5) in combination with concanavalin A influences both 3H-thymidine uptake in lymphocytes in vitro and the production of interferon. After in vivo pretreatment of adult mice with thymosin the mitogen-induced interferon production was about 3 times higher than in controls. The produced interferon is immune interferon (IFN gamma) as determined by rho H 2-sensitivity and lack of neutralization by mouse IFN beta-antibodies.

Rabbits were immunized using isolated and dissolved specific immune complexes obtained from patients suffering from early syphilis. After immunization the rabbits were infected intradermally with living Treponema pallidum. Some of them did not develop lesions at the infection sites. In comparison to controls there was a delayed and reduced production of antibodies. The effect of immunization may be induced by a treponemal protein antigen as a constituent of the specific immune complexes.

In the acute phase of systemic lupus erythematosus the serum contains factors, with molecular weights ranging from 780,000 daltons to 1.5 million daltons, which induce blast transformation of autologous lymphocytes. In addition to the high-molecular weight components, low-molecular weight factors (75,000 and 160,000 daltons) which also induce an increase in lymphocytic transformation have also been demonstrated. In contrast to the high-molecular weight components the low-molecular factors stimulate the transformation of autologous and homologous lymphocytes. During transformation, lysis of autologous target fibroblasts occurs. The low-molecular weight mitogenic components remain stable after 30 min at 56 degrees C. The significance of such mediators for the pathogenesis of systemic lupus erythematosus is discussed.

Sublethally irradiated AB/Bln, mice (800 c Gy) and supplemented with syngeneic bone marrow cells were treated with or without a splenopentin derivative (DAc SP-5) and compared for their capacity to produce antibodies. In bone marrow cell plus DAc SP-5 treated animals antibody forming cells were found earlier and in a higher frequency than in mice treated with bone marrow cells only. These findings demonstrate that DAc SP-5 is able to induce bone marrow cell maturation.

Epidermal Langerhans cells (ELC) are bone marrow-derived immune cells that are important in allergic contact dermatitis. We examined the influence of calcium transport inhibitors, lanthanum and diltiazem hydrochloride, on allergic contact dermatitis induced by 1-chloro-2,4-dinitrobenzene (DNCB) in BALB/c mice. Systemic lanthanum at a dose of 0.08 mg/kg and topical lanthanum (50 microliters of 10% solution) were given 5 d before DNCB sensitization. Systemic diltiazem (30 mg/kg per dy) was given for 3 d during sensitization with DNCB. In all animals, challenge with topical DNCB to the ear skin was performed 5 d after sensitization and ear swelling was measured. Twenty four hours post-DNCB challenge, animals receiving systemic lanthanum demonstrated a 56% decrease in contact hypersensitivity (ear swelling) compared with non-lanthanum-treated animals (0.08 +/- 0.03 mm vs 0.18 mm +/- 0.02 mm, p less than 0.01). Topical lanthanum produced a 58% decrease in contact hypersensitivity (0.20 +/- 0.02 mm vs 0.41 +/- 0.03 mm, p less than 0.01). The DNCB-induced ear swelling also resolved more quickly in animals treated with lanthanum. Systemic diltiazem produced a 67% decrease in ear swelling (0.05 +/- 0.01 mm vs 0.15 +/- 0.02 mm, p less than 0.001). A decrease in epidermal Langerhans cell density of 13 to 14% was produced by systemic lanthanum, detected by both ATPase staining and Ia staining, respectively (p less than 0.05). Approximately 20% of the Langerhans cells were morphologically abnormal, having become "rounded," and lacking normal dendritic processes. From these results, we infer that calcium transport across the cell membrane of ELC may be important in the regulation of their function. Lanthanides and other calcium-channel blockers may be useful pharmacologic agents to probe these phenomena.

Sublethally irradiated C57Bl/6 mice (whole body irradiation with 600 cGy) were treated with or without diacetyl splenopentin and compared for their capacity to produce antibodies against target sheep red blood cells. As demonstrated, mice treated with splenopentin produced antibodies earlier and in a higher level than animals untreated.

In former investigations our group obtained an immuno-reconstituting effect in mice treated by immunosuppression after a continuous treatment with splenopentin (SP5). The goal of the present study was to test whether a small number of injections right after immunosuppression possibly produces the same result in the sense of an initial effect. Although a short-term therapy induced an increase of antibody formation which was measurable after 4 weeks, the study clearly showed that only a continuous treatment by SP5 led to an optimum, i.e. complete reconstitution of antibody formation.

To determine the role of T-cell subsets in wound healing, we studied the granulation tissue proliferation after depletion of CD4 or CD8 positive cells. Granulation tissue proliferation in CD8-diminished AB mice was significantly higher than in the control group as a result of depleted suppressor cell activity. The CD4-depleted mice produced granulation tissue in less than 30% of the control group. To investigate the role of dipeptidylpeptidase IV on CD4 positive cells in wound healing we used Lys-[Z(NO2)]-Pro, a chemically modified dipeptide which may result by degradation of polypeptides by this peptidase. It was possible to restore the diminished capability of granulation tissue proliferation in CD4-depleted mice by a single treatment with the dipeptide Lys-[Z(NO2)]-Pro. Our results suggest that: (i) the CD4 positive T-helper subset regulates wound healing, and (ii) products of degradation by dipeptidylpeptidase IV may bypass T-helper cell function.