Oligometastatic disease and visceral resections in advanced malignant melanoma: a propensity-matched analysis

PURPOSE

Malignant melanoma is among the tumours with the highest increase in incidence of solid tumours in Germany. While most patients are diagnosed at an early stage and show a good prognosis, advanced stages of malignant melanoma are accompanied with a poor prognosis and limited treatment options. Comparable to other tumour entities, the resection of visceral metastases could lead to a better prognosis. Supplementary, the subgroup of oligometastatic patients might benefit from surgical therapy to a greater extent.

METHODS

This retrospective study analysed 351 patients treated between 2006 and 2017 at the University Hospital of Cologne. A total of 121 patients showed visceral metastases, with which we compared patients with a diffuse tumour spread to patients in an oligometastatic state. Furthermore, we evaluated the effect of visceral resection of oligometastatic, malignant melanoma.

RESULTS

Our analysis showed that patients with an oligometastatic malignant melanoma had a significantly better prognosis than patients with a diffuse pattern of metastases, if they showed visceral metastases. Furthermore, the resection of visceral metastases leads to a significant gain in median overall survival time (13.6 vs. 34.2 months) and in progression-free survival (9.6 vs. 3.8 months).

CONCLUSION

The resection of visceral metastases is a rational treatment option in advanced malignant melanoma. Although our study is limited by a small cohort of patients (n = 18), we believe that the resection of visceral metastases will be fundamental in the treatment of malignant melanoma. In particular, patients in an oligometastatic stage could be an eligible group for surgical treatment.

Introduction of laparoscopic nephrectomy for autosomal dominant polycystic kidney disease as the standard procedure

PURPOSE

Autosomal dominant polycystic kidney disease (ADPKD) is a common hereditary disorder and accounts for 5-10% of all cases of kidney failure. 50% of ADPKD patients reach kidney failure by the age of 58 years requiring dialysis or transplantation. Nephrectomy is performed in up to 20% of patients due to compressive symptoms, renal-related complications or in preparation for kidney transplantation. However, due to the large kidney size in ADPKD, nephrectomy can come with a considerable burden. Here we evaluate our institution's experience of laparoscopic nephrectomy (LN) as an alternative to open nephrectomy (ON) for ADPKD patients.

MATERIALS AND METHODS

We report the results of the first 12 consecutive LN for ADPKD from August 2020 to August 2021 in our institution. These results were compared with the 12 most recent performed ON for ADPKD at the same institution (09/2017 to 07/2020). Intra- and postoperative parameters were collected and analyzed. Health related quality of life (HRQoL) was assessed using the SF36 questionnaire.

RESULTS

Age, sex, and median preoperative kidney volumes were not significantly different between the two analyzed groups. Intraoperative estimated blood loss was significantly less in the laparoscopic group (33 ml (0-200 ml)) in comparison to the open group (186 ml (0-800 ml)) and postoperative need for blood transfusion was significantly reduced in the laparoscopic group (p = 0.0462). Operative time was significantly longer if LN was performed (158 min (85-227 min)) compared to the open procedure (107 min (56-174 min)) (p = 0.0079). In both groups one postoperative complication Clavien Dindo ≥ 3 occurred with the need of revision surgery. SF36 HRQol questionnaire revealed excellent postoperative quality of life after LN.

CONCLUSION

LN in ADPKD patients is a safe and effective operative procedure independent of kidney size with excellent postoperative outcomes and benefits of minimally invasive surgery. Compared with the open procedure patients profit from significantly less need for transfusion with comparable postoperative complication rates. However significant longer operation times need to be taken in account.

Operating room time savings in Germany- and UK-based hospitals with 3D- VS. 2D-imaging technology in laparoscopic surgery: Meta analysis and budget impact model - Health economic evaluation

AIMS

Opportunity cost (OC) analysis is key when evaluating surgical techniques. Operating room (OR) time is one potential source of OC in laparoscopic surgery. This study quantifies differences in OR time between 3D- and 2D-imaging technology in laparoscopic surgery, translates these into OC and models the economic impact in real-world hospitals.

METHODS

First a systematically performed literature review and meta-analysis were conducted. Then, methods to translate OR time savings into OC were theorised and a budget impact model was created. After that, the potential time savings of real-world hospital case mixes were extrapolated. Finally, the opportunity costs of not using 3D-imaging in laparoscopic surgery were evaluated.

RESULTS

Average OR time saving per laparoscopic procedure was -19.4 min (-24.3; -14.5) (-14%) in favour of 3D. The Budget Impact Model demonstrated an economic impact of using 3D-laparoscopy instead of 2D laparoscopy, ranging from £183,045-£866,316 in the British and 73,049€-437,829€ in German hospitals, modelling a mixture of cost savings and performing additional procedures (earning additional revenue).

CONCLUSION

The OC analysis revealed significant economic benefits of introducing 3D-imaging technology in laparoscopic surgery, on the basis that average procedure time is reduced. Utilising the saved OR time to perform additional procedures was the biggest driver of OC. Hospital case mix and procedure volume indicated the magnitude of the OC.

[New techniques and training methods for robot-assisted surgery and cost-benefit analysis of Ivor Lewis esophagectomy]

INTRODUCTION

Robotic surgery was introduced into general surgery more than 20 years ago. Shortly afterwards, Horgan performed the first robotic-assisted esophagectomy in 2003 in Chicago. The aim of this manuscript is to elucidate new developments and training methods in robotic surgery with a cost-benefit analysis for robotic-assisted Ivor Lewis esophagectomy.

METHODS

Systematic literature search regarding new technology and training methods for robotic surgery and cost analysis of intraoperative materials for hybrid and robotic-assisted Ivor Lewis esophagectomy.

RESULTS

Robotic-assisted esophageal surgery is complex and involves an extensive learning curve, which can be shortened with modern teaching methods. New robotic systems aim at the use of image-guided surgery and artificial intelligence. Robotic-assisted surgery of esophageal cancer is significantly more expensive that surgery without this technology.

CONCLUSION

Oncological short-term and long-term benefits need to be further evaluated to support the higher cost of robotic esophageal cancer surgery.

The economic burden of endoscopic treatment for anastomotic leaks following oncological Ivor Lewis esophagectomy

Background

Complications after surgery for esophageal cancer are associated with significant resource utilization. The aim of this study was to analyze the economic burden of two frequently used endoscopic treatments for anastomotic leak management after esophageal surgery: Treatment with a Self-expanding Metal Stent (SEMS) and Endoscopic Vacuum Therapy (EVT).

Materials and methods

Between January 2012 and December 2016, we identified 60 German-Diagnosis Related Group (G-DRG) cases of patients who received a SEMS and / or EVT for esophageal anastomotic leaks. Direct costs per case were analyzed according to the Institute for Remuneration System in Hospitals (InEK) cost-accounting approach by comparing DRG payments on the case level, including all extra fees per DRG catalogue.

Results

In total, 60 DRG cases were identified. Of these, 15 patients were excluded because they received a combination of SEMS and EVT. Another 6 cases could not be included due to incomplete DRG data. Finally, N = 39 DRG cases were analyzed from a profit-center perspective. A further analysis of the most frequent DRG code -G03- including InEK cost accounting, revealed almost twice the deficit for the EVT group (N = 13 cases, € - 9.282 per average case) compared to that for the SEMS group (N = 9 cases, € - 5.156 per average case).

Conclusion

Endoscopic treatments with SEMS and EVT for anastomotic leaks following oncological Ivor Lewis esophagectomies are not cost-efficient for German hospitals. Due to longer hospitalization and insufficient reimbursements, EVT is twice as costly as SEMS treatment. An adequate DRG cost compensation is needed for SEMS and EVT.

Immune checkpoints programmed death 1 ligand 1 and cytotoxic T lymphocyte associated molecule 4 in gastric adenocarcinoma

Remarkable efficacy of immune checkpoint inhibition has been reported for several types of solid tumors and early studies in gastric adenocarcinoma are promising. A detailed knowledge about the natural biology of immune checkpoints in gastric adenocarcinoma is essential for clinical and translational evaluation of these drugs. This study is a comprehensive analysis of cytotoxic T lymphocyte associated molecule 4 (CTLA-4) and programmed death 1 ligand 1 (PD-L1) expression in gastric adenocarcinoma. PD-L1 and CTLA-4 were stained on tumor sections of 127 Caucasian patients with gastric adenocarcinoma by immunohistochemistry (IHC) and somatic mutation profiling was performed using targeted next-generation sequencing. Expression of PD-L1 and CTLA-4 on lymphocytes in tumor sections, tumor-draining lymph nodes (TDLN) and peripheral blood were studied by flow-cytometry and immune-fluorescence microscopy in an additional cohort. PD-L1 and CTLA-4 were expressed in 44.9% (57/127) and 86.6% (110/127) of the analyzed gastric adenocarcinoma samples, respectively. Positive tumor cell staining for PD-L1 or CTLA-4 was associated with inferior overall survival. Somatic mutational analysis did not reveal a correlation to expression of PD-L1 or CTLA-4 on tumor cells. Expression of PD-1 (52.2%), PD-L1 (42.2%) and CTLA-4 (1.6%) on tumor infiltrating T cells was significantly elevated compared to peripheral blood. Of note, PD-1 and PD-L1 were expressed far higher by tumor-infiltrating lymphocytes than CTLA-4. In conclusion, specific immune checkpoint-inhibitors should be evaluated in this disease and the combination with molecular targeted therapies might be of benefit. An extensive immune monitoring should accompany these studies to better understand their mode of action in the tumor microenvironment.

Validation of 2-mm tissue microarray technology in gastric cancer. Agreement of 2-mm TMAs and full sections for Glut-1 and Hif-1 alpha

BACKGROUND/AIM

Tissue Microarray (TMA) is a widely used method to perform high-throughput immunohistochemical analyses on different tissues by arraying small sample cores from paraffin-fixed tissues into a single paraffin block. TMA-technology has been validated on numerous cancer tissues and also for gastric cancer studies, although it has not been validated for this tumor tissue so far. The objective of this study was to assess, whether the 2-mm TMA-technology is able to provide representative samples of gastric cancer tissue.

MATERIALS AND METHODS

TMA paraffin blocks were constructed by means of 220 formalin-fixed and paraffin-embedded gastric cancer samples with a sample diameter of 2 mm. The agreement of immunohistochemical stainings of Glut-1 and Hif-1 alpha in TMA sections and the original full sections was calculated using kappa statistics and direct adjustment.

RESULTS

The congruence was substantial for Glut-1 (kappa 0.64) and Hif-1 alpha (kappa 0.70), but with an agreement of only 71% and 52% within the marker-positive cases of the full-section slides.

CONCLUSION

Due to tumor heterogeneity primarily, the TMA technology with a 2-mm sample core shows relevant limitations in gastric cancer tissue. Although being helpful for tissue screening purposes, the 2-mm TMA technology cannot be recommended as a method equal to full-section investigations in gastric cancer.

Autocrine growth limitation of human papillomavirus type 16-harboring keratinocytes by constitutively released tumor necrosis factor-alpha

TNF-alpha is known to exert antitumor and antiviral effects and to participate in the regulation of the immune response. In our study we demonstrate that human rTNF-alpha specifically blocks growth of SK-v keratinocyte cell line harboring and expressing human papillomavirus type 16 (HPV16) sequences. This inhibitory effect was shown by [3H]TdR incorporation and cell counting. Binding experiments with 125I-TNF-alpha showed that SK-v cells express about 10,000 single class TNF-alpha R per cell with affinity constant of about 0.7 nM. Binding of 125I-TNF-alpha could be inhibited by htr-9 mAb recognizing a 55/60-kDa type I TNF-alpha R but not by utr-1 mAb recognizing 75/80-kDa type II TNF-alpha R or irrelevant mAb specific for HPV16E7 protein. Addition of anti-TNF-alpha antibodies to SK-v cell culture resulted in significant (p < 0.05), dose-dependent stimulation of their proliferation. SK-v cells constitutively expressed TNF-alpha mRNA, and SK-v CM contained TNF-alpha, as demonstrated by Northern blot analysis, a specific ELISA, Western blot analysis, and a bioassay with TNF-alpha-sensitive L-M cells. HPLC gel filtration of SK-v cell CM showed that the factor cytotoxic for L-M cells coeluted with immunoreactive TNF-alpha. These results demonstrate that HPV16-harboring SK-v cells constitutively express and release immunoreactive and biologically active TNF-alpha that in turn may exert an autocrine growth inhibitory effect. This phenomenon could represent one of the self-limiting mechanisms controling growth of HPV-induced neoplasia.

Autocrine growth limitation of human papillomavirus type 16-harboring keratinocytes by constitutively released tumor necrosis factor-alpha

TNF-alpha is known to exert antitumor and antiviral effects and to participate in the regulation of the immune response. In our study we demonstrate that human rTNF-alpha specifically blocks growth of SK-v keratinocyte cell line harboring and expressing human papillomavirus type 16 (HPV16) sequences. This inhibitory effect was shown by [3H]TdR incorporation and cell counting. Binding experiments with 125I-TNF-alpha showed that SK-v cells express about 10,000 single class TNF-alpha R per cell with affinity constant of about 0.7 nM. Binding of 125I-TNF-alpha could be inhibited by htr-9 mAb recognizing a 55/60-kDa type I TNF-alpha R but not by utr-1 mAb recognizing 75/80-kDa type II TNF-alpha R or irrelevant mAb specific for HPV16E7 protein. Addition of anti-TNF-alpha antibodies to SK-v cell culture resulted in significant (p < 0.05), dose-dependent stimulation of their proliferation. SK-v cells constitutively expressed TNF-alpha mRNA, and SK-v CM contained TNF-alpha, as demonstrated by Northern blot analysis, a specific ELISA, Western blot analysis, and a bioassay with TNF-alpha-sensitive L-M cells. HPLC gel filtration of SK-v cell CM showed that the factor cytotoxic for L-M cells coeluted with immunoreactive TNF-alpha. These results demonstrate that HPV16-harboring SK-v cells constitutively express and release immunoreactive and biologically active TNF-alpha that in turn may exert an autocrine growth inhibitory effect. This phenomenon could represent one of the self-limiting mechanisms controling growth of HPV-induced neoplasia.

Production of natural killer cell activity-augmenting factor (interleukin-6) by human epiphyseal chondrocytes

OBJECTIVE

We sought to determine the capacity of human epiphyseal chondrocytes to modulate the cytotoxic activity of human natural killer (NK) cells by determining whether they release interleukin-6 (IL-6), a cytokine recently shown to stimulate NK cell activity.

METHODS

Conditioned medium from human epiphyseal chondrocyte cultures (Ch-CM) was tested for IL-6 activity using the B9 cell hybridoma assay. Its NK cell-stimulating capacity in the presence of K562 (myelogenous leukemia) cells or human chondrocytes was evaluated in a 4-hour 51Cr-release assay. Ch-CM-derived IL-6/NK cell-augmenting factor activity was partially purified by high-performance liquid chromatography (HPLC) gel filtration and Western blot.

RESULTS

Ch-CM contained an NK cell-augmenting factor (NKAF) which was blocked by IL-2 or IL-6 antibodies. Ch-CM did not contain detectable IL-2 activity, but it stimulated IL-2 production by human peripheral blood lymphocytes (PBL). This IL-2-inducing capacity was inhibited by IL-6 antibodies, indicating that chondrocytes release an IL-6-like activity. Ch-CM significantly enhanced the proliferation of IL-6-dependent B9 hybridoma cells, and Western blot analysis of Ch-CM revealed specific bands corresponding to those of highly purified IL-6. Upon HPLC gel filtration, chondrocyte NKAF copurified with chondrocyte IL-6. Pure IL-6 and chondrocyte IL-6 were tested for their ability to stimulate the cytotoxic activity of human PBL against chondrocytes. Both mediators significantly enhanced chondrocyte killing. Lysis of chondrocytes by PBL was mediated by NK cells, since depletion of CD16+ cells resulted in inhibition of the activity.

CONCLUSION

Thus, upon stimulation, chondrocytes produce IL-6 which, through IL-2 induction, augments the activity of NK cells against K562 target cells as well as against chondrocytes.

Treatment of systemic sclerosis with gamma-interferon

Numerous drugs have been recommended for the treatment of systemic sclerosis, but without any significant effect on the fibrotic stage of this disorder. Because recombinant gamma-interferon (gamma-IFN) is a potent and selective inhibitor of fibroblast proliferation and collagen production by human dermal fibroblasts in vitro, we assessed the effects of gamma-IFN treatment on the skin and on pulmonary function in patients with systemic sclerosis. Fourteen patients entered the study, and nine completed the 12-month trial. Fifty micrograms/day of gamma-IFN was administered subcutaneously 3 days per week. At the end of the 12-month treatment period a significant improvement was observed in total skin score, and blood gas analysis showed a significant increase in Pa O2 during therapy with gamma-interferon. Other clinical parameters (dysphagia, Raynaud's phenomenon, cardiac involvement) were not altered significantly. No serious adverse effects were noted. These results suggest a beneficial effect of gamma-IFN on the cutaneous fibrotic abnormalities and on lung fibrosis in systemic sclerosis.

Modulation of intercellular Adhesion Molecule-1 Expression on Human Melanocytes and Melanoma Cells: Evidence for a Regulatory Role of IL-6, IL-7, TNFβ, and UVB Light

Intercellular adhesion molecule-1 (ICAM-1) is involved in cell-cell interactions of leukocytes and parenchymal cells and thus plays an important role in immunologic and inflammatory reactions. The expression of ICAM-1 that is found on many different cells such as melanocytes and melanoma cells is induced by various cytokines, including interferon-gamma (IFN gamma), interleukin (IL)-1 and tumor necrosis factor alpha (TNF alpha). Because expression of ICAM-1 in melanoma was found to correlate with increased risk of metastasis, the regulation of ICAM-1 expression on human melanocytes and melanoma cells was investigated. Foreskin-derived melanocytes and melanoma cell lines (A375, G361) were incubated with different cytokines and ICAM-1 expression was evaluated by fluorescence-activated cell sorter. IFN gamma, IL-1, IL-7, TNF alpha, and TNF beta significantly upregulated ICAM-1 expression in a dose-dependent manner. Most interestingly, the cytokine IL-6, which does not influence adhesion-molecule expression on other cells, significantly upregulated melanocyte and melanoma cell ICAM-1 expression. This effect was dose dependent and could be blocked by an IL-6 antibody. Irradiation with ultraviolet (UVB) light did not influence constitutive ICAM-1 expression on melanoma cells and melanocytes, but suppressed cytokine-induced ICAM-1 expression when cells were harvested 16 h after irradiation. These findings were further confirmed by Northern blot analysis, showing a marked accumulation of ICAM-1 mRNA after cytokine treatment, which was reduced by irradiation with UVB light. However, when UVB-exposed melanoma cells were cultured for at least 48 h induction of ICAM-1 expression was observed. These data indicate that, similar to other cells, ICAM-1 expression on melanoma cells and melanocytes is regulated by cytokines and that UVB light affects ICAM-1 expression on melanocytic cells in a biphasic manner.

Interleukin-6 expression by fibroblasts grown in three-dimensional gel cultures

We investigated the expression and biological activity of interleukin-6 (IL-6) by human fibroblasts cultured as monolayers and within three-dimensional type I collagen lattices. In the course of contracting the gel to a dense tissue-like structure, the cells upregulated their levels of IL-6 mRNA as well as IL-6 biological activity. While there was little mRNA and protein activity (6,500 U/ml) in monolayer cultures, fibroblasts in the 3D system showed a 13-fold increase in IL-6 mRNA on day 3. IL-6 protein was increased 6-fold (38,000 U/ml) on day 4. Stimulation of fibroblast cultures with IL-1 alpha resulted in enhanced IL-6 production in both systems, but the fibroblasts embedded into the 3D network continued to exhibit higher levels.

Hexagonal surface gradient coil for localized MRS of the heart

A surface gradient coil designed to obtain localized magnetic resonance spectroscopy of the heart in vivo is described. Images and 31P spectra from phantoms and both pig and dog hearts in vivo are shown. The coil was used in conjunction with a rf surface coil to obtain 31P spectra from transmural sections of the left ventricular wall of a dog heart in vivo to demonstrate differences between normal and ischemic tissue.

Constitutive release of IL6 by human papillomavirus type 16 (HPV16)-harboring keratinocytes: a mechanism augmenting the NK-cell-mediated lysis of HPV-bearing neoplastic cells

In the present study we demonstrate that the cultured human keratinocyte cell line (SK-v cells) harboring and expressing integrated human papillomavirus type 16 (HPV16) DNA sequences constitutively releases IL6, which is known as a pleiotropic immunoregulatory cytokine of potential antitumor properties. The presence of IL6 activity in SK-v cell-conditioned media (SK-v CM) was demonstrated by tritiated thymidine incorporation into IL6-dependent B9 murine plasmacytoma cells. The effect on B9 cells was specific since it could be inhibited by anti-IL6 neutralizing antibodies but not by a normal control serum. IL6 did not affect SK-v cell growth; however, it significantly augmented NK cell activity of human peripheral blood lymphocytes against both K562 erytholeukemic and SK-v cells as assessed by 51Cr release assay. SK-v CM displayed NK cell-augmenting activity that copurified with IL6 activity in both size exclusion and anion-exchange HPLC. Furthermore, SK-v cell-derived NK cell stimulatory activity could be neutralized with anti-IL6 antibodies. These results suggest that HPV-harboring neoplastic cells can release IL6 which may indirectly mediate tumor death by augmentation of NK cell activity.

Increased IL-6 production by monocytes and keratinocytes in patients with psoriasis

Interleukin-6 (IL-6) is a multifunctional inflammatory cytokine that is produced by monocytes and keratinocytes upon stimulation. Because psoriasis is a skin disease characterized by a hyperproliferative activity of keratinocytes and an inflammatory infiltrate, in the present study IL-6 production of monocytes and keratinocytes of patients with psoriasis was investigated. Peripheral blood mononuclear cells (PBMC) derived from psoriatics, atopics, and healthy controls were incubated for 24 h and, subsequently, supernatant IL-6 activity was measured using an IL-6-dependent hybridoma cell line (B9). Compared to controls and atopics, PBMC of psoriatics produced significantly increased amounts of biologically active IL-6. These findings were also confirmed by Western blot analysis using a specific antiserum directed against IL-6. Moreover, when the sera of the same patients were tested for IL-6 activity, sera of psoriatics contained significantly elevated amounts of circulating IL-6 in comparison to samples from atopics and healthy controls. In contrast to normal or uninvolved skin, keratinocytes in psoriatic lesions were remarkably positive for IL-6 as detected by immunohistochemistry and in situ hybridization. In addition, IL-6 also was found to induce its own synthesis and release by monocytes. These findings indicate that keratinocytes and monocytes in psoriasis are activated to produce increased amounts of IL-6, which may be one of the mediators involved in the regulation of both local and systemic inflammatory reactions occurring in skin diseases such as psoriasis.

Regulation of epidermal cell interleukin-6 production by UV light and corticosteroids

Epidermal cells (EC) are well known as a source of cytokines, including interleukin (IL)-6. In the present study, we investigated whether ultraviolet (UV) light and corticosteroids (CS) affect IL-6 production by normal (HNK) or malignant (KB) human keratinocytes. Supernatants derived from UVB (100 J/m2)- but not from UVA (100-1500 kJ/m2)-exposed EC (HNK and KB) contained significantly increased levels of IL-6 activity. This was also confirmed by Western blot analysis, resulting in specific bands at 23 kD and 27 kD. Northern blot analysis revealed an enhanced IL-6 mRNA expression after UVB exposure. Addition of hydrocortisone, prednisolone, or dexamethasone immediately after UVB irradiation significantly blocked UVB or IL-1-induced IL-6 mRNA expression and production by EC. The suppressive effect was observed at doses in the physiologic (10(-7)-10(-9) M) as well as pharmacologic (10(-5)-10(-7) M) range. In contrast, the nonactive steroid prednisone did not affect EC IL-6 mRNA expression. These findings indicate that increased IL-6 production by EC after UVB irradiation may mediate local and systemic inflammatory reactions following extensive sun exposure. Thus, the therapeutic effect of corticosteroids observed in various inflammatory diseases may be partly due to their downregulating capacity of IL-6 production.

Human keratinocytes are a source for tumor necrosis factor alpha: evidence for synthesis and release upon stimulation with endotoxin or ultraviolet light

Tumor necrosis factor alpha (TNF-alpha), in addition to being cytotoxic for certain tumor cells, has turned out as a multifunctional cytokine that is involved in the regulation of immunity and inflammation. Since human keratinocytes have been demonstrated to be a potent source of various cytokines, it was investigated whether epidermal cells synthesize and release TNF-alpha. Supernatants derived from normal human keratinocytes (HNK) and human epidermoid carcinoma cell lines (KB, A431) were tested both in a TNF-alpha-specific ELISA and a bioassay. In supernatants of untreated epidermal cells, no or minimal TNF-alpha activity was found, while after stimulation with lipopolysaccharide (LPS) or ultraviolet (UV) light, significant amounts were detected. Western blot analysis using an antibody directed against human TNF-alpha revealed a molecular mass of 17 kD for keratinocyte-derived TNF-alpha. These biological and biochemical data were also confirmed by Northern blot analysis revealing mRNA specific for TNF-alpha in LPS- or ultraviolet B (UVB)-treated HNK and KB cells. In addition, increased TNF-alpha levels were detected in the serum obtained from human volunteers 12 and 24 h after a single total body UVB exposure, which caused a severe sunburn reaction. These findings indicate that keratinocytes upon stimulation are able to synthesize and release TNF-alpha, which may gain access to the circulation. Thus, TNF-alpha in concert with other epidermal cell-derived cytokines may mediate local and systemic inflammatory reactions during host defense against injurious events caused by microbial agents or UV irradiation.

[Studies on the production of epidermal cytokines after UVB irradiation in patients with epidermodysplasia verruciformis]

The production of interleukin-1 (IL-1) and interleukin-1 inhibitor by keratinocytes isolated from the skin of epidermodysplasia verruciformis patients was studied. Keratinocytes from uninvolved skin of patients with most pronounced neoplastic lesions produced large amounts of an IL-1 inhibitor (20-40 kD). Keratinocytes from preneoplastic lesions showed no significant differences compared to cells from healthy donors but their production of IL-1 after UVB irradiation was increased.

Epidermal cell-contra-interleukin 1 inhibits human accessory cell function by specifically blocking interleukin 1 activity

Ultraviolet B (UVB) radiation (280-320 nm) is capable of suppressing selected cell mediated immune responses by inhibiting the function of antigen presenting/accessory cells. Human keratinocytes and carcinoma cell lines (A431) upon UVB radiation or treatment with PMA secrete a suppressor factor, which blocks IL 1 activity (hEC-contra-IL 1). Therefore, the capacity of this UVB-inducible cytokine to modulate human accessory cell function was tested. Human peripheral blood mononuclear cells were stimulated with the mitogenic anti-CD3 monoclonal antibody OKT3 and thymidine incorporation into proliferating T-cells was measured as an index for monocyte accessory cell activity. Addition of hEC-contra-IL 1 which was purified by HPLC chromatography partially decreased OKT3 induced T-cell proliferation in a dose dependent manner. Human EC-contra-IL 1, however, failed to inhibit blastogenesis when T-cells depleted of accessory cells were stimulated in an accessory cell independent fashion via OKT3 attached to the bottom of microtiter plates. Recombinant human (rh) IL 1, but not rhIL 6 was able to reconstitute hEC-contra-IL 1 suppressed blastogenesis in a dose dependent manner. Furthermore, the combined addition of h-EC-contra-IL 1 and an antibody against rhIL 6 to cultures resulted in an additive inhibitory effect which could not be observed when hEC-contra-IL 1 was added together with a monoclonal antibody against rhIL 1 alpha/beta. These studies indicate that hEC-contra-IL 1 is capable of suppressing human accessory cell function by specifically blocking IL 1 activity. This property of hEC-contra-IL 1 points to a novel mechanism by which UVB radiation may modulate human accessory cell function in an indirect manner.

Binding of recombinant interleukin-1 beta to the third complement component and alpha 2-macroglobulin after activation of serum by immune complexes

Activation of human normal serum with tetanus/antitetanus immune complexes (TAT-IC) resulted in increased binding of 125I-labeled interleukin-1 beta (IL-1 beta) to serum factors, as opposed to untreated serum. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by autoradiography showed labeling of two large molecular mass factors of an apparent molecular weight (Mr) of 200,000 and 400,000, respectively. These complexes could be dissociated by reduction. No complexes were formed when reducing compounds were added to serum-TAT-IC-125I-IL-1 beta mixtures. Complex formation was largely prevented by alkylating compounds. Molecular sieve chromatography of TAT-IC-activated serum confirmed that 125I-IL-1 beta became bound to high Mr serum proteins. Fractions containing high molecular 125I-IL-1 serum protein complexes partially retained IL-1-like activity since they induced proliferation of an IL-1-dependent murine T helper (D10G4) cell lineage. The 125I-IL-1 beta binding factors could be immunoprecipitated from TAT-IC-activated serum 125I-IL-1 beta solutions by antisera to alpha 2-macroglobulin (alpha 2M) or to the third complement component (C3). SDS-PAGE of the immunoprecipitates showed radioactive bands corresponding to the expected Mr resulting from complex formation between 125I-IL-1 beta and these two proteins. Treatment of purified plasma alpha 2M and C3 with trypsin or activation with methylamine, which causes cleavage of the internal thiol ester and the appearance of free thiol groups in these proteins, mediated binding of 125I-IL-1 beta to alpha 2M and C3b. The results suggest that cleavage of the internal thiol ester in C3 and alpha 2M makes these plasma proteins susceptible to binding of 125I-IL-1 beta and that free thiol groups do play a role in the formation of 125I-IL-1 beta plasma protein complexes. Activated C3 and alpha 2M may function as IL-1 beta carrier proteins in biologic fluids, in addition to their other physiologic roles.

Ultraviolet light induces increased circulating interleukin-6 in humans

Although the clinical effects of acute exposure to ultraviolet (UV) light--such as cutaneous inflammation, malaise, somnolence, chills and fever--have been appreciated many years, the underlying mechanisms mediating these effects are poorly understood. Interleukin-6 (IL-6) is a potent cytokine with a wide variety of biologic activities, including induction of fever and acute phase response. Because IL-6 is produced by keratinocytes in vivo and in vitro and because the release is enhanced by UV light, the present study was performed to investigate the effect of a single UV dose eliciting moderate to severe sunburn reaction on the production of IL-6 in vivo. Therefore, plasma of UV-treated human subjects was evaluated for IL-6 activity by testing its capacity to induce the proliferation of an IL-6-dependent hybridoma cell line (B9). In contrast to plasma samples obtained before UV exposure, post-UV-specimens contained significant levels of IL-6 peaking at 12 h after UV irradiation. Plasma IL-6 activity was neutralized by an antiserum directed against recombinant human IL-6, and upon HPLC gel filtration exhibited a molecular weight of around 20 kD. Moreover, plasma IL-6 levels correlated remarkably with fever course followed by an increase of acute phase proteins such as C-reactive protein. These data indicate that IL-6, which is released by keratinocytes following UV exposure, may gain access to the circulation and via its pyrogenic as well as acute phase-inducing effect may function as an important mediator of systemic sunburn reaction.

IFN-beta 2/IL-6 augments the activity of human natural killer cells

MHC nonrestricted cytotoxic cells play an important role in the killing of tumor cells in vitro and potentially in vivo. The activity of these cells is regulated by several cytokines such as IL-2 and IFN. In the present study we provide first evidence that IL-6 significantly augments the cytotoxic activity of human NK cells. IL-6 is produced by many different cells and is also known as IFN-beta 2, B cell stimulatory factor 2, hybridoma growth factor, hepatocyte-stimulating factor, and 26 kDa protein. IL-6 stimulates the activity of human CD3- NK cells but not that of CD3+ non-MHC-restricted cytotoxic T lymphocytes. As is the case with IL-2, the IL-6-mediated augmented cytotoxicity was a result of a more efficient lysis, but was not caused by an increased effector to target cell binding. Moreover, the effect of IL-6 on NK cell activity was blocked by a mAb directed against IL-2, and IL-6 itself was found to be a potent inducer of IL-2 production in cultured human PBMC. Thus it may be concluded that IL-6 enhances the cytotoxic activity of NK cells via IL-2. This newly recognized property of IL-6, which is produced by almost any cell, may be of importance in host defense against microbes and malignancies and therefore could contribute to improve the adoptive immunotherapy by using lymphokine-activated killer cells.

IFN-beta 2/IL-6 augments the activity of human natural killer cells

MHC nonrestricted cytotoxic cells play an important role in the killing of tumor cells in vitro and potentially in vivo. The activity of these cells is regulated by several cytokines such as IL-2 and IFN. In the present study we provide first evidence that IL-6 significantly augments the cytotoxic activity of human NK cells. IL-6 is produced by many different cells and is also known as IFN-beta 2, B cell stimulatory factor 2, hybridoma growth factor, hepatocyte-stimulating factor, and 26 kDa protein. IL-6 stimulates the activity of human CD3- NK cells but not that of CD3+ non-MHC-restricted cytotoxic T lymphocytes. As is the case with IL-2, the IL-6-mediated augmented cytotoxicity was a result of a more efficient lysis, but was not caused by an increased effector to target cell binding. Moreover, the effect of IL-6 on NK cell activity was blocked by a mAb directed against IL-2, and IL-6 itself was found to be a potent inducer of IL-2 production in cultured human PBMC. Thus it may be concluded that IL-6 enhances the cytotoxic activity of NK cells via IL-2. This newly recognized property of IL-6, which is produced by almost any cell, may be of importance in host defense against microbes and malignancies and therefore could contribute to improve the adoptive immunotherapy by using lymphokine-activated killer cells.

IFN-beta 2, B cell differentiation factor 2, or hybridoma growth factor (IL-6) is expressed and released by human epidermal cells and epidermoid carcinoma cell lines

IL-6, which is also known as IFN-beta 2, hybridoma growth factor, hepatocyte-stimulating factor, and B cell differentiation factor, mediates acute phase responses including fever, has lymphocyte-stimulating capacities, and antiviral activity. IL-6 is produced by monocytes, fibroblasts, certain lymphocytes, and various tumor cells. The present study demonstrates that this multifunctional cytokine is released also by normal human epidermal cells (EC) and human epidermoid carcinoma cell lines (A431, KB). Accordingly, supernatants derived from freshly isolated EC, long term keratinocyte cultures, A431, or KB cells stimulated the proliferation of a hybridoma growth factor/IL-6-dependent plasmacytoma cell line (B9). IL-6 constitutively was produced in the presence of serum proteins. The addition of IL-1 alpha, IL-1 beta, or the tumor promoter PMA significantly enhanced the synthesis and release of EC-derived IL-6 (EC-IL 6). Like monocyte or fibroblast-derived IL-6, EC-IL-6 exhibited Mr microheterogeneity within 21 and 28 kDa. Similarly in Western blotting experiments an antiserum directed against human rIFN-beta 2/IL-6 detected the different Mr forms of EC-IL-6. Moreover, this antiserum was able to block the B9 cell growth-promoting capacity of EC-IL-6 strongly suggesting that this EC-derived mediator is closely related, if not identical with IL-6. This was further confirmed by Northern blot analysis detecting IL-6 specific mRNA both in long term cultured keratinocytes and A431 cells by hybridization with a cDNA fragment encoding for B cell differentiating factor 2/IL-6. Therefore, in addition to the production of other cytokines as previously reported, EC and in particular keratinocytes also synthesize and release IL-6. This further supports the important regulatory role of the epidermis during the pathogenesis of inflammatory, autoimmune, and neoplastic diseases.

IFN-beta 2, B cell differentiation factor 2, or hybridoma growth factor (IL-6) is expressed and released by human epidermal cells and epidermoid carcinoma cell lines

IL-6, which is also known as IFN-beta 2, hybridoma growth factor, hepatocyte-stimulating factor, and B cell differentiation factor, mediates acute phase responses including fever, has lymphocyte-stimulating capacities, and antiviral activity. IL-6 is produced by monocytes, fibroblasts, certain lymphocytes, and various tumor cells. The present study demonstrates that this multifunctional cytokine is released also by normal human epidermal cells (EC) and human epidermoid carcinoma cell lines (A431, KB). Accordingly, supernatants derived from freshly isolated EC, long term keratinocyte cultures, A431, or KB cells stimulated the proliferation of a hybridoma growth factor/IL-6-dependent plasmacytoma cell line (B9). IL-6 constitutively was produced in the presence of serum proteins. The addition of IL-1 alpha, IL-1 beta, or the tumor promoter PMA significantly enhanced the synthesis and release of EC-derived IL-6 (EC-IL 6). Like monocyte or fibroblast-derived IL-6, EC-IL-6 exhibited Mr microheterogeneity within 21 and 28 kDa. Similarly in Western blotting experiments an antiserum directed against human rIFN-beta 2/IL-6 detected the different Mr forms of EC-IL-6. Moreover, this antiserum was able to block the B9 cell growth-promoting capacity of EC-IL-6 strongly suggesting that this EC-derived mediator is closely related, if not identical with IL-6. This was further confirmed by Northern blot analysis detecting IL-6 specific mRNA both in long term cultured keratinocytes and A431 cells by hybridization with a cDNA fragment encoding for B cell differentiating factor 2/IL-6. Therefore, in addition to the production of other cytokines as previously reported, EC and in particular keratinocytes also synthesize and release IL-6. This further supports the important regulatory role of the epidermis during the pathogenesis of inflammatory, autoimmune, and neoplastic diseases.

Expression and release of interleukin-1 by different human melanoma cell lines

The influence of immunologic parameters on the clinical course of malignant melanoma is increasingly evident. However, it is not known which factors contribute to the immunologic host reaction against malignant melanoma. Because epidermal cells and, in particular, normal as well as transformed keratinocytes recently have been demonstrated to release various immunomodulating cytokines, the capacity of melanoma cells to produce interleukin-1 (IL-1) was examined. Accordingly, supernatants derived from different melanoma cell lines contained significant levels of IL-1 activity. Upon high-performance liquid chromatography (HPLC) gel filtration, melanoma cell-derived IL-1 (MEL-IL-1) exhibited molecular weight heterogeneity, and HPLC chromatofocusing revealed major activity at pH 5.0 and minor activity at pH 7.0. A monoclonal antibody directed against monocyte-derived IL-1 blocked MEL-IL-1 activity significantly and was able to precipitate four species of biosynthetically radiolabeled MEL-IL-1 (25, 17, 6, and 4 kilodaltons), suggesting that MEL-IL-1 is identical to monocyte-derived IL-1. This was also confirmed by Northern blot analysis detecting IL-1 alpha specific mRNA in melanoma cells by hybridization with a cDNA fragment encoding for IL-1 alpha. Thus, melanoma cells, like other epidermal cells, exhibit the capacity to release the immunomodulating cytokine IL-1 and, therefore, probably have the potency to influence host defense mechanisms directed against malignant melanoma.

Detection of a specific inhibitor of interleukin 1 in sera of UVB-treated mice

It was recently demonstrated that murine keratinocytes upon irradiation with ultraviolet (UV) light release an immunosuppressive cytokine which blocks the biological activity of interleukin 1 (IL 1). This epidermal cell derived inhibitor (EC-contra IL 1) exhibits a molecular weight of 40 kD and a pI of approximately 9.0. EC-contra IL 1 in vivo possibly may penetrate through the basal lamina and subsequently cause systemic immunosuppression following UV-exposure. In the present study, we tested whether EC-contra IL 1 can also be detected in vivo. Serum samples obtained from total body UV-exposed mice were subjected to HPLC gel filtration and tested for IL 1 inhibitory activity. While a non-specific high molecular weight (300 kD) suppressor factor was detected in sera of both UV-exposed and sham treated control mice, a specific IL 1 inhibitor exhibiting a molecular weight of 40 kD was observed only in sera of UV-exposed mice. This cytokine named serum-contra IL 1 was maximally released 24 h after UV-exposure, exhibited a pI of 9.0, and blocked the activity of natural as well as recombinant interleukin 1 in a dose dependent manner. Serum-contra IL 1 did not suppress interleukin 2 or interleukin 3 and did not inhibit spontaneous cell proliferation. The present biochemical and biologic data suggest that serum-contra IL 1 and EC-contra IL 1 appear to be closely related if not identical. These observations therefore indicate that keratinocytes upon UV-irradiation in vivo release EC-contra IL 1 which may at least partly be responsible for the immunosuppression following UV-exposure.

Cytokine production in patients with newly diagnosed insulin-dependent (type I) diabetes mellitus

There is ample evidence that cell-mediated immune mechanisms are crucial in the initiation of insulin-dependent diabetes mellitus (IDDM). Therefore, the role of cytokines in the pathogenesis of IDDM was investigated in 51 patients with IDDM, in comparison with 20 normal controls. The patients were divided into three groups, group 1 consisting of 31 newly diagnosed type 1 diabetics, in group 2 IDDM had been diagnosed for between 2 months and 2 years, and in group 3 onset had occurred 2-20 years before. Interleukin 1 (IL 1) activity was measured by the thymocyte co-stimulator assay, and interleukin 2 (IL 2) using IL 2 dependent cell lines. Peripheral blood monocyte IL 1 production was not altered under basal conditions. However, silica-stimulated IL 1 release was normal in patients with newly diagnosed or short-term disease, but was significantly decreased in long-term diabetics. Peripheral blood T-lymphocyte IL 2 production at onset of IDDM was normal under basal conditions, and upon optimal stimulation with concanavalin A (ConA) and phorbol myristate acetate (PMA). However, in the two groups with longer standing diabetes, basal and stimulated IL 2 release was decreased. We conclude that monocytes and T-lymphocytes from patients with diabetes mellitus have a diminished capacity to release IL 1 and IL 2 only later in the course of the disease. At the time of manifestation of disease, IL 1 and IL 2 production is normal in type-I diabetes mellitus.

[Surgically treated carpal tunnel syndrome--clinical and electrophysiologic follow-up]

The carpal tunnel syndrome is described as a compression of the N. medianus under the retinaculum flexorum with the causes for this syndrome being of the most varied nature. The aetiology is multifactorial with frequent alterations of the connective tissue being observed in the histological specimen, i.e. chronic inflammatory proliferations or fibrotic degenerations. Direct pressure measurements have shown that the pressure is markedly higher both at rest and extension or flexion as compared to normal healthy subjects. An exact diagnosis requires a measurable prolongation of the distal motorial latency. Surgery is the treatment of choice to ensure perfect recovery. For this purpose the retinaculum flexorum must be entirely split, and our experiments have shown that the splitting of the epineurium yields good results. The microsurgical interfascicular neurolysis, however, should be considered in special cases only. Complaints tend to disappear fairly quickly in the majority of cases, i.e. pain recedes by 90%, sensitivity disorders by more than 70% and muscle atrophy by 50%. The operation enables a measurable improvement of the distal motorial latency. The incidence of postoperative complications is relatively low, and if they do occur, then they are negligible and without any bearing on the final surgical result. Persistent residual complaints are very often due to other accompanying diseases such as cervical vertebral column syndrome, cervical ribs etc.

[Pathophysiology and methods of treatment in renal hypertension in renal artery aneurysms]

Aneurysms of the renal artery occur infrequently and remain mostly asymptomatic. A review of the pertinant literature reveals approximately 300 reports. Hypertension is the predominant sign and affects two thirds of all patients, particularly in aneurysms complicated by stenosis or thromboembolism of renal artery, which is caused by the renin-angiotensin-mechanism. A solitary renal aneurysm causes no renal hypertension; 66% of all diagnosed renal artery aneurysms require no treatment. Resection of the aneurysm and direct suture was done in half of all operated patients. Only in 27 cases operative treatment consisted of extirpation and patch-plastic (autologic or alloplastic). Two additional cases in our own hospital with resection and patch-plastic are described. By using those techniques it is possible to normalize renal artery blood flow as well as blood pressure. Other well-known surgical procedures are nephrectomy, aorto-renalbypass and several others.

[Use of volar veins in finger replantation]

The number and the location of the venous anastomosis in finger replantation are discussed. The principle: 'two veins for one artery' has been given up in favour to do only one venous anastomosis. A vein on the palmar side should be preferred. Here the anastomosis is protected by a thicker layer of subcutanous tissue. In addition this technique allows to do the total vascular reconstruction without turning the hand. In a number of 84 finger replantations there was a failure rate of 9,5% by using only one vein for replantation. In 17 finger replantations using one volar vein we lost only one finger (5.9%).

[Dynamic stressing of petrochanterically osteotomized femurs treated with endoprostheses (author's transl)]

In the treatment of pertochanteric fractures of the femur, the use of a hip joint prosthesis is indicated in exceptional cases for patients of advanced age. Mechanical testing of the combined system (osteotomized bone-cement-prosthesis) reveals high resistance to stress. A report is presented on stress tests on pertrochanterically osteotomized cadaver femurs which have been treated with endoprostheses. Dynamic stressing was done in four stages up to a maximal force of 2050 N. The resulting movement was measured medially and laterally along the osteotomy fissure. In the medial area it was between 0 and 0.06 mm, and in the lateral between 0 and 0.2 mm. The mechanical stability of this combined system seems to be higher than other surgical methods (Ender-nailing, combined osteosynthesis with bone cement and angle plate). Its load bearing capacity is substantially greater than that of the physiological system.