Immunmodulatoren (Biologicals) in der Therapie von Patienten mit chronischen Dermatosen in der dermatologischen Praxis

Wir fassen Erfahrungen zusammen, die in unserer dermatologischen Praxis in den letzten Jahren, besonders seit der Einrichtung einer Spezialsprechstunde Immundermatologie, mit dem Einsatz von Biologicals gemacht wurden. Dazu charakterisieren wir mittels retrospektiver Auswertung die behandelten Patienten mit Psoriasis (mit und ohne Psoriasis-Arthritis), Neurodermitis, Urtikaria und Akne inversa. Es werden klinische Aspekte der Immunmodulation mittels der Blockade von Zytokinen (TNFα, IL-17, IL-23), deren Rezeptoren (IL-4/13R, IL-17R) bzw. IgE analysiert. Wir zeigen, dass der konsequente Einsatz von Biologicals eine klare organisatorische Entscheidung mit mannigfaltigen Konsequenzen für die gesamte Praxis und das Team darstellt.

Impfen bei dermatologischen Patienten vor und unter immunmodulierenden Therapien – Erfahrungen aus einer ambulanten Spezialsprechstunde

Impfen heißt, durch Auslösen einer aktiven Immunität den entsprechenden (Infektions-)Krankheiten vorzubeugen. Dem kommt durch die immer zahlreicher verfügbaren immunmodulierenden Therapien für dermato-onkologische, Autoimmun- und allergische Erkrankungen eine zunehmende Bedeutung zu. Wir möchten darstellen, vor welche Herausforderungen wir uns beim Aufbau eines Impfmanagements für die derzeit über 80 Patientinnen und Patienten unserer Spezialsprechstunde „Immundermatologie“ gestellt sehen.

P6357Left ventricular unloading leads to heart rhythm stabilization in cardiogenic shock - Results from the Dresden Impella Registry

Background

Cardiogenic shock (CS) is often associated with severe heart rhythm disturbances (SHRD). Percutaneous left ventricular assist devices (pLVAD) can actively unload the left ventricle (LV) using a micro-axial pump and resulting in a decreased end-diastolic pressure and wall tension. These parameters are suspected to induce and maintain rhythmological instability.

Purpose

In the current study, we firstly describe the termination of SHRD immediately (less than 5 minutes) after LV-unloading in CS patients with previous unsuccessful antiarrhythmic treatment.

Methods

The Dresden Impella Registry is an ongoing single center registry. Since 2014, a total of 97 patients were included. Each of whom had received a micro-axial heart pump in refractory CS supplying a circulatory support of 3.5 l/min. We investigated the subgroup of patients which initially exhibited SHRD like ventricular tachycardia or ventricular fibrillation, and showed an immediately stabilization of heart rhythm directly after insertion of pLVAD (HRS). This subgroup was compared with the other patients of the registry (NHRS). Therefore, clinical laboratory and hemodynamic parameters were measured and analyzed.

Results

In 19 patients of the registry a HRS was observed. Among these patients, a CPR before pLVAD was performed in 89.5% with a mean duration of 30.7min, whereby 52.6% sustained an in-hospital cardiac arrest and 36.9% an out-of-hospital cardiac arrest respectively. In the NHRS subgroup (n=78), a CPR was performed less frequently (39.7%; p<0.001) with shorter mean duration (19.5min; p=0.016) and a lower out-of-hospital ratio (12.8%; p=0.014). The comparison of hemodynamic parameters between the HRS and NHRS cohort showed no difference in mean arterial pressure, heart rate, left ventricular ejection fraction (LVEF), and serum lactate.

The mortality showed no differences between the HRS and NHRS cohort at 30 days (68.4% vs. 58.1%; p=0.413) and 90 days (78.9% vs. 66.7%; p=0.306), despite a more frequent and longer CPR with a higher ratio of out-of-hospital cardiac arrests among the HRS patients. There was also no difference in mortality between patients, who received an in-hospital CPR. However, HRS patients with in-hospital CPR showed a significantly lower serum lactate and NA dosage compared to the NHRS cohort (Figure A & B). Furthermore, NA recovery, defined as 50% decrease as compared to the initial NA dosage, occurred more frequently in the HRS group (HRS 42.9% vs. NHRS 7.1%; p=0.049). The LVEF nearly double in the HRS subgroup after LV-unloading, whereas it did not change in the NHRS subgroup (relative LVEF increase: HRS 95% vs. NHRS 15%).

Figure A & B

Conclusion

The termination of SHRD due to LV-unloading occurred in around 20% of CS patients in Dresden Impella Registry and was associated with a lower serum lactate and NA dosage as well as an improved LVEF among patients with in-hospital CPR.

Acknowledgement/Funding

None

Testikulärer Keimzelltumor in Form eines Rhabdomyosarkoms (high grade) bei einem HIV-Infizierten mit Psoriasis vulgaris unter Therapie mit Adalimumab

Bei einer HIV-Infektion besteht ein allgemein erhöhtes Tumorrisiko. Im Genitalbereich treten vor allem HPV-assoziierte Karzinome gehäuft auf. Bisher wurden Keimzelltumoren mit somatischer Malignität in Form eines Rhabdomyosarkoms bei HIV-Infektion kaum beschrieben. Im Folgenden stellen wir einen 47-jährigen Patienten mit HIV-Infektion und ausgeprägter Psoriasis vulgaris vor, bei welchem sich unter einer Therapie mit Adalimumab ein testikulärer, nicht-seminomatöser Keimzelltumor mit reifen Teratom-, Dottersacktumoranteilen und somatischer Malignität in Form eines Rhabdomyosarkoms (high grade) im Bereich des rechten Hodens entwickelte. Mit Feststellung der Raumforderung wurde die Therapie mit Adalimumab gestoppt und das Rhabdomyosarkom reseziert. 4 Monate nach Ablatio testis kam es zu einem ausgeprägten Lokalrezidiv mit V. a. eine regionale Weichteilmetastase und V. a. Lymphknotenmetastasen iliacal bds. Es erfolgte eine erneute Resektion und eine adjuvante Chemotherapie mit Epirubicin/Ifosfamid. Ein Einfluss des TNF-Alpha-Blockers Adalimumab auf die Bildung des Rhabdomyosarkoms kann nicht ausgeschlossen werden. Bei HIV-Infektion und gleichzeitiger Therapie mit TNF-Alpha-Blockern ist folglich verstärkt auf ein erhöhtes Tumorrisiko zu achten.

Abstract P2-08-21: Stromal co-expression of urokinase-type plasminogen activator (uPA) and plasminogen activator Inhibitor (PAI-1) protein by IHC predicts poor disease outcome in endocrine-treated postmenopausal patients with receptor-positive early breast cancer

Background Elevated levels of intratumoral uPA and PAI-1 in ELISA-based measurements are associated with a high recurrence risk and allow to identify patients who might particularly benefit from adjuvant chemotherapy. The clinical utility of ELISA-based protein analysis is, however, greatly limited by the requirement of fresh tumor tisssue. We have therefore evaluated in a large clinical trial patient cohort with long-follow-up whether immunohistochemical detection of uPA and PAI-1 in FFPE archived tumor samples is also able to identify women with poor prognosis.

Patients and Methods 547 postmenopausal women with hormone receptor–positive, early breast cancer who had received at least 5 years of endocrine therapy in the prospectively designed ABCSG-06 trial, and in whom FFPE tumor tissue was available, were included in this analysis. uPA and PAI-1 protein expression was evaluated by immunohistochemistry, and correlated with distant-disease free (DDFS) and overall survival (OS).

Results Stromal co-expression of uPA and PAI-1 was detected in 166 of 276 (60%) evaluable tumor samples and was weakly associated with tumor size (p=0.012, Chi Square test) but not with age, nodal status, grading, or receptor status. Women with intratumoral uPA/PAI-1 expression were more likely to have a shorter DDFS in multivariate analysis (HR for relapse p=1.870; 95% CI 1.184-2.955; p=0.007 Cox regression analysis) and and OS (adjusted HR for death p=1.291; 95% CI 0.928-1.795; p=0.129) than women without. After a median follow-up of 10 years, women with uPA/PAI-1-positive tumors experienced a significantly shorter DDFS (p&lt;0.0001 log rank test) and OS (p=0.020).

Conclusions Stromal co-expression of uPA and PAI-1 in breast cancer samples predicts poor DDFS and OS in postmenopausal women with hormone-receptor positive early-stage breast cancer who receive endocrine therapy.

Citation Format: Singer CF, Filipits M, Jahn S, Abete L, Jakesz R, Greil R, Bauernhofer T, Kwasny W, Seifert M, Fitzal F, Schmitt M, Moinfar F, Gnant M. Stromal co-expression of urokinase-type plasminogen activator (uPA) and plasminogen activator Inhibitor (PAI-1) protein by IHC predicts poor disease outcome in endocrine-treated postmenopausal patients with receptor-positive early breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-08-21.

Probing DNA with micro- and nanocapillaries and optical tweezers

We combine for the first time optical tweezer experiments with the resistive pulse technique based on capillaries. Quartz glass capillaries are pulled into a conical shape with tip diameters as small as 27 nm. Here, we discuss the translocation of λ-phage DNA which is driven by an electrophoretic force through the nanocapillary. The resulting change in ionic current indicates the folding state of single λ-phage DNA molecules. Our flow cell design allows for the straightforward incorporation of optical tweezers. We show that a DNA molecule attached to an optically trapped colloid is pulled into a capillary by electrophoretic forces. The detected electrophoretic force is in good agreement with measurements in solid-state nanopores.

Evaluation of the 'GeneDisc' real-time PCR system for detection of enterohaemorrhagic Escherichia coli (EHEC) O26, O103, O111, O145 and O157 strains according to their virulence markers and their O- and H-antigen-associated genes

AIMS

To evaluate the GeneDisc multiplex real-time PCR assay for detection of enterohaemorrhagic Escherichia coli (EHEC) O26, O103, O111, O145 and O157 strains.

METHODS AND RESULTS

GeneDiscs for detection of genes encoding Shiga toxins (stx), intimins (eae), E. coli O157 (rfbE(O157)) and H7 (fliC(H7)) antigens as well as genes specific for EHEC O26 (wzx(O26)), O103 (wzx(O103)), O111 (wbd1(O111)), O145 (ihp1(O145)) and O157 (ihp1(O157)) were evaluated. The assay was run with native bacteria in 1 h in a GeneDisc Cycler. All genotypes of stx and eae, except stx(2f) and eae-rho, were identified. Escherichia coli strains belonging to O-groups O26, O103, O111, O157 as well as EHEC O145:[H28] strains were specifically detected with this assay. The ihp1(O157) gene was not found specific for EHEC O157. O-rough mutants of EHEC and non-motile EHEC O157 strains were reliably identified with the GeneDisc assay. Two to three colonies of EHEC strains were still detectable in a lawn of 50 000 apathogenic E. coli from agar plates.

CONCLUSIONS

The GeneDisc assay is a specific and reliable assay for detection of major EHEC strains. It is robust enough to detect few EHEC colonies in mixed cultures of bacteria.

SIGNIFICANCE AND IMPACT OF THE STUDY

The assay is promising for its use in EHEC diagnostics and for EHEC monitoring with different kinds of samples.

Longitudinal excitations in Mg–Al–O refractory oxide melts studied by inelastic x-ray scattering

The dynamic structure factor S(Q,omega) of the refractory oxide melts MgAl2O4 and MgAl4O7 is studied by inelastic x-ray scattering with aerodynamic levitation and laser heating. This technique allows the authors to measure simultaneously the elastic response and transport properties of melts under extreme temperatures. Over the wave vector Q range of 1-8 nm-1 the data can be fitted with a generalized hydrodynamic model that incorporates a slow component described by a single relaxation time and an effectively instantaneous fast component. Their study provides estimates of high-frequency sound velocities and viscosities of the Mg-Al-O melts. In contrast to liquid metals, the dispersion of the high-frequency sound mode is found to be linear, and the generalized viscosity to be Q independent. Both experiment and simulation show a weak viscosity maximum around the MgAl4O7 composition.

In vitroHerstellung von Sehnenkonstrukten aus humanen mesenchymalen Stammzellen und einem Kollagen Typ I Gel

BACKGROUND AND PURPOSE

Reconstruction of tendon tissue is problematic in many cases. Since direct tendon suture is often impossible, major reconstruction with the use of free tendon transplants or tendon transposition is necessary. Important motor units often have to be sacrificed for reconstructive purposes. In this study we investigated whether long tendon-like substitutes can be fabricated in vitro from human mesenchymal stem cells (MSCs) and a collagen type I gel when cultured under cyclic stretching conditions.

MATERIAL AND METHODS

MSCs were obtained from bone marrow aspirates of the iliac crest. Cells were suspended in a collagen type I gel and polymerized in a glass-cylinder with defined size. The fabricated tendon substitutes underwent static stretching for 14 days followed by cyclic stretching for 21 days in a special manufactured bioreactor. Non-stretched substitutes served as a control.

RESULTS

Macroscopically the stretched tendon substitutes showed an increased opacity and a smoother surface structure compared to the non-stretched control. The stretched substitutes displayed more spindle-shaped, longitudinal orientated cells, a tendon-like organization of the collagen matrix, and a parallel organization of the collagen fibers when stained with Hematoxylin/Eosin and Elastica.

CONCLUSION

Long tendon substitutes could be fabricated from MSCs and a collagen type I gel by cyclic stretching and showed tendon-like parallel collagen fibers and spindle-shaped cells. The use of MSCs in combination with adequate scaffold materials has great therapeutic potential for the development of autologous transplantable tendon substitutes.

Einfluss des Schwamm- und Schlauchmaterials der Vacuum Assisted Closure Device (V.A.C.®) auf die Konzentration von Transforming Growth Factor beta 1 in Wundflüssigkeit

BACKGROUND AND PURPOSE

The Vacuum Assisted Closure device (V.A.C.) is commonly used for the treatment of problematic wounds. Furthermore, wound fluid can be easily collected with this device for research purposes. However, there is inadequate information as to whether the measurement of biomoieties of importance to wound healing is affected by the exposure of wound fluid to V.A.C. components, namely Polyurethane-foam and tubing. This study is an attempt to evaluate whether exposure of wound fluid to either V.A.C.-components affects concentrations of transforming growth factor beta 1 (TGF-b1) in wound fluid.

MATERIAL AND METHOD

Wound fluid was gathered from five decubital ulcer patients using the foil-technique and was exposed to sterile pieces of the V.A.C. Polyurethane-foam, tubing material or nothing for zero, one or five hours. Saline served as control. The concentration of TGF-b1 was measured using sandwich-ELISA. The resulting data were analyzed using two-way ANOVA, Newman-Keuls and Bonferroni t-Test.

RESULTS

The concentration of TGF-b1 decreased significant in all three groups during the five hours of the experiment (p < 0.05). There was no significant decrease in TGF-b1 concentration at any time point in-between the groups.

CONCLUSION

From this study, we conclude that wound-fluid collected from the V.A.C.-device via the polyurethane-foam or tubing for purposes of analyzing concentrations of TGF-beta 1 should not be different from fluid collected using the foil technique.

Primary cutaneous follicle center cell lymphomas and large B cell lymphomas of the leg descend from germinal center cells. A single cell polymerase chain reaction analysis

Primary cutaneous B cell lymphomas are defined as non-Hodgkin lymphomas that occur in the skin without extracutaneous involvement for 6 mo after diagnosis. They are characterized by a less aggressive course and better prognosis than their nodal counterparts. According to the European Organization for Research and Treatment of Cancer classification, the major subentities of primary cutaneous B cell lymphoma are follicle center cell lymphomas, immunocytomas, and large B cell lymphomas of the leg, which differ considerably regarding their clinical behavior, the former two being indolent, the latter being of intermediate malignancy. In this study, we applied a single cell polymerase chain reaction approach to analyze immunoglobulin V(H)/V(L) genes in 532 individual B lymphocytes from histologic sections of four follicle center cell lymphomas localized on the head and trunk, and four large B cell lymphomas on the leg. We found: (i) in six of eight patients a clonal heavy chain, and in seven of eight patients a clonal light chain rearrangement, all being potentially productive; (ii) no bias in VH gene usage, in four of seven light chain rearrangements the V kappa germline gene IGVK3-20*1 was used; (iii) no biallelic rearrangements; (iv) all V(H)/V(L) genes are extensively mutated (mutation rate 5.4-16.3%); (v) intraclonal diversity in six of eight cases (three of each group); and (vi) low replacement vs silent mutation ratios in framework regions indicating preservation of antigen-receptor structure, as in normal B cells selected for antibody expression. Our data indicate a germinal center cell origin of primary cutaneous follicle center cell lymphomas and large B cell lymphomas independent of those belonging to one of these subentities.

Development of single-chain Fv fragments from a human anti-double-stranded DNA antibody to study the influence of somatic mutations on antigen binding

OBJECTIVE

The monoclonal IgG anti-double-stranded (ds) DNA antibody 32B9, obtained from a patient with systemic lupus erythematosus, was found to be encoded by somatically mutated immunoglobulin genes. We examined the input of several somatic mutations into antibody specificity and affinity.

METHODS

Five single-chain (sc) Fv fragments [variable domain of the heavy chain (V(H))-linker-variable domain of the light chain (V(L))] derived from 32B9 were constructed and expressed in Escherichia coli. These scFv fragments contained V(H) or V(L) fragments, differing in the somatic mutation pattern. The antigen binding features of the 32B9 IgG were compared with the corresponding scFv fragments, and the binding to DNA of all fragments was analyzed by ELISA. Binding constants to dsDNA were determined by surface plasmon resonance and ELISA.

RESULTS

The scFv 32B9 reflected the binding features of the 32B9 IgG. Independently of the somatic mutations, all scFv fragments bound to dsDNA in ELISA. The affinity data indicated that the mutations studied had only a marginal effect on affinity maturation of the 32B9.

DISCUSSION

We discuss the approach to constructing scFv fragments as a tool to study autoantibody maturation.

Cover design for radioactive and AMD-producing mine waste in the Ronneburg area, eastern Thuringia

At the former uranium mining site of Ronneburg, large scale underground and open pit mining for nearly 40 years resulted in a production of about 113,000 tonnes of uranium and about 200 million cubic metres of mine waste. In their present state, these materials cause risks to human health and strong environmental impacts and therefore demand remedial action. The remediation options available are relocation of mine spoil into the open pit and on site remediation by landscaping/contouring, placement of a cover and revegetation. A suitable vegetated cover system combined with a surface water drainage system provides long-term stability against erosion and reduces acid generation thereby meeting the main remediation objectives which are long-term reduction of radiological exposure and contaminant emissions and recultivation. The design of the cover system includes the evaluation of geotechnical, radiological, hydrological, geochemical and ecological criteria and models. The optimized overall model for the cover system has to comply with general conditions as, e.g. economic efficiency, public acceptance and sustainability. Most critical elements for the long-term performance of the cover system designed for the Beerwalde dump are the barrier system and its long-term integrity and a largely self-sustainable vegetation.

Microanatomical compartments of clonal and reactive T cells in mycosis fungoides: molecular demonstration by single cell polymerase chain reaction of T cell receptor gene rearrangements

Mycosis fungoides (MF) is a cutaneous T cell lymphoma, clinically characterized by patches, plaques and tumors occurring in successive stages of the disease. In early MF, an infiltrate consisting of mainly reactive T cells is seen in the papillary dermis while tumor cells are mostly confined to the epidermis. By contrast, later stages show nodular infiltrates formed mostly of tumor cells in the dermis while the epidermis is relatively devoid of tumor cells; however, knowledge of the localization of clonal T cells has been based on histomorphologic features and immunohistochemical stainings visualizing certain V-beta subfamilies of the T cell receptor (TCR). As these techniques do not allow for an unequivocal identification of clonal tumor cells, we used micromanipulation and single cell PCR amplifying the TCR chain gene rearrangement. A total number of 387 single T cells was isolated from six skin biopsies in five patients in patch, plaque, and tumor stages. Of these, 180 T cells were picked from the epidermis and 207 from the dermal infiltrate. The rearranged TCR-gamma DNA could be sequenced from 181 of 387 T cells. In three of six patients representing all three stages, epidermal T cells with a clonal rearrangement could be amplified. In early plaque stage a higher degree of epidermal T lymphocytes was found than in initial patch, later plaque, and tumor stages with an inverse distribution found for reactive T lymphocytes. In two patients a biallelic rearrangement was demonstrated that had not been detected in prior PCR analysis from blood and skin samples. These data show that clonal (neoplastic) and non-clonal (reactive) T lymphocytes in MF preferentially infiltrate different microanatomical compartments of the skin, depending on the stage of disease. The microanatomically distinct localization of reactive and clonal T cells suggests that the absence of direct contact between tumor and host-defense lymphocytes may contribute to tumor persistence and progression in epidermis, peripheral blood, and deep dermal tumor cell nests, respectively.

Clonal evolution in a primary cutaneous follicle center B cell lymphoma revealed by single cell analysis in sequential biopsies

B cell neoplasias descending from germinal center cells harbor the hallmark of intraclonal diversity resulting from ongoing mutation in the variable parts of their immunoglobulin-encoding genes. To characterize a primary cutaneous follicle center B cell lymphoma in more detail, we analyzed the respective VH and VL genes in single cells mobilized from four sequential biopsies, three taken from the skin and one obtained after internal dissemination from a retrobulbar infiltrate. The lymphoma cells were found to contain V5-51/D6-12/JH5b (heavy chain) and A27/Jkappa2 (light chain) gene rearrangements detected on both the genomic and the transcriptional level. To provide an accurate mutation analysis, the specific VH gene counterpart (V5-51UK) was cloned from the patient's germline. Analyzing 226 single cells, we found: (i) complete nucleotide identity when VH and VL genes of lymphoma cells from one particular biopsy were compared among each other; (ii) intraclonal diversity due to ongoing mutation comparing the sequences obtained from sequential biopsies; (iii) both VH and VL genes to be highly mutated. Deducing from the sequence data, we propose a scenario of the clonal evolution of the B cell tumor in this patient. From the molecular-biological point of view, this primary cutaneous follicle center B cell lymphoma shows the features of a germinal center cell lymphoma. To draw this conclusion from single cell PCR data, however, a sample of sequential biopsies had to be analyzed.

Cytokine expression in primary cutaneous germinal center cell lymphomas

Physiologically, B-lymphocytes are not present in the skin. Even in pathological situations they rarely occur. In contrast, primary cutaneous B-cell lymphomas (CBCL) are characterized by proliferation of B lymphocytes within the skin. This suggests the existence of a certain microenvironment supporting homing and expansion of clonal B cells. Cytokines were demonstrated to be involved in the pathogenesis of cutaneous lymphomas of T-cell origin. Cytokine expression in cutaneous B-cell lymphoma lesions, however, has not been investigated so far. Therefore, the mRNA level of several cytokines was analyzed in biopsies from 7 patients with CBCL and compared to pleomorphic T-cell lymphoma (n = 6), psoriasis (n = 9), and healthy skin (n = 7), using a competitive RT-PCR approach. An overexpression of TNF-alpha, IL-10, and IL-6 was found. Enhanced IL-8 mRNA expression was detected in 2/7 cases. The overexpression of IL-6 and IL-10 in CBCL might be of particular importance, since these cytokines are considered to support B-cell growth. Additionally, the overexpression of IL-10 may contribute to tumor progression since this immunosuppressive cytokine might be involved in downregulation of immunological tumor surveillance, in part by inhibiting type 1 cytokine formation. In fact, we did not detect IFN-gamma and IL-2 expression. Taken together, we found a cytokine pattern in CBCL lesions which might contribute to tumor B-cell growth.

Analysis of V(H)-D-J(H) gene transcripts in B cells infiltrating the salivary glands and lymph node tissues of patients with Sjögren's syndrome

OBJECTIVE

In patients with Sjögren's syndrome (SS), B lymphocytes have been found to infiltrate salivary glands, resulting in sialadenitis and keratoconjunctivitis. The disease is frequently associated with benign and neoplastic lymphoproliferation. The present study was undertaken to investigate whether clonal B cell expansion takes place in lymphocytic infiltrations of salivary glands under (auto- [?]) antigen stimulation, by analyzing in more detail the variable part (V(H)-D-J(H)) of the immunoglobulin heavy chain genes expressed in these B cells.

METHODS

Biopsies of the labial salivary glands and lymph nodes were performed on 2 female patients with SS. The Ig gene rearrangements in these tissues were amplified by reverse transcriptase-polymerase chain reaction using specific primers.

RESULTS

A total of 94 V(H)-D-J(H) transcripts were cloned and sequenced. Our data suggest a polyclonal origin of the B cell infiltrates. In 92 of the transcripts, V(H) genes were modified by somatic mutation. Further analysis showed counterselection for replacement mutations within the framework regions, suggesting that those B cells were stimulated and selected for functional expression of a surface Ig. In labial salivary glands from both patients, clonally related B cells became evident. Members of 1 particular clone were found in both the lip and lymph node material.

CONCLUSION

These data provide evidence, on the nucleotide sequence level, that an antigen-triggered clonal B cell expansion takes place in the salivary glands of patients with SS who do not have histologic evidence of developing lymphoma. It may be speculated that those B cell clones expand during disease progression, resulting in lymphomagenesis.

Mainly unmutated V(H) genes rearranged in B cells forming germinal centers in a cutaneous pleomorphic T-cell lymphoma

B cells in skin lesions of a pleomorphic cutaneous T-cell lymphoma with reactive germinal center hyperplasia were analyzed for their immunoglobulin V(H)DJ(H) gene rearrangements by micromanipulation and single cell polymerase chain reaction (PCR) analysis. In B lymphocytes located in germinal center-like structures, we found in 11/16 different V(H)DJ(H) rearrangements completely unmutated VH genes, suggesting that those cells did not undergo antigen-driven selection. Two V(H) genes showed more than 98% germ-line identity. In only three cells V(H) segments were somatically mutated to a higher extent, but two of these rearrangements were non-productive. These results differ markedly from what we have previously detected in B cells present in mycosis fungoides, another entity of cutaneous T-cell lymphomas where the Ig gene repertoire resembles the situation in peripheral blood with a significantly higher proportion of mutated V(H) genes. When investigating the large atypical B cells strongly expressing CD30 which were detected within the T-cell zone outside the germinal centers, we found again, in most cases, that the rearranged VH genes were completely unmutated. The B cells were of polyclonal origin. Due to this comparable Ig gene repertoire and mutational pattern, we suggest that these cells descend from the germinal center centroblasts which migrated into the T-cell zone and obviously became stimulated to express the CD30 marker. The micromanipulation technique and molecular analysis on the single cell level may provide an important input into our understanding of the mechanisms of immune regulation in cutaneous lymphomas.

Nucleotide sequence comparison of the IgE constant region in patients with atopic dermatitis and non-atopic individuals

In order to answer the question whether the Fc portion of the IgE molecule in patients with atopic dermatitis is altered by somatic replacement mutations, we amplified and sequenced the respective C epsilon 2 and C epsilon 3 domain genes. Five patients with atopic dermatitis and 6 non-atopic individuals were studied. Neither within the C epsilon 2 nor the C epsilon 3 domain could any common nucleotide substitutions be detected. Therefore, the conclusion can be drawn that, in patients with atopic dermatitis, there are no protein sequence differences within the Fc part of the IgE which could be responsible for distinct functional features with regard to Fc epsilon-receptor binding and signal transduction or could account for the frequent occurrence of anti-IgE autoantibodies in these individuals.

Analysis of V(H) genes rearranged by individual B cells in dermal infiltrates of patients with mycosis fungoides

In patients with cutaneous T cell lymphomas such as mycosis fungoides B cells can frequently be detected in the lymphocytic dermal infiltrate. To analyse their immunoglobulin heavy chain gene repertoire, single B cells were obtained from tissue sections of two typical patients with mycosis fungoides using hydraulic micromanipulation followed by specific amplification of the respective gene segments by single-cell polymerase chain reaction (PCR) technique. A total of 21 V(H)DJ(H) genes was sequenced. From each individual B cell a single productive V(H)DJ(H) rearrangement was obtained. There was no clonal relationship detected between any of these rearrangements suggesting polyclonality of the infiltrating B cells. The representation of V(H) families was in accordance with the germ-line complexity. A remarkably high number of V(H) genes (5/13 in patient 1; 3/8 in patient 2) was completely or nearly germ-line-identical. Five of seven V(H)4 family genes were nearly unmutated. On the other hand, most of the V(H)3 gene family members were somatically mutated in an antigen-driven manner. The proportion of germ-line-identical V(H) genes, the usage of individual V(H), D, J(H) gene elements, and the pattern of somatic mutations found in the B cells infiltrating skin lesions of patients with mycosis fungoides resembles the peripheral blood repertoire, suggesting a bystander role of these cells.

Molecular analysis of the immunoglobulin VH gene rearrangement in a primary cutaneous immunoblastic B-cell lymphoma by micromanipulation and single-cell PCR

The immunoglobulin VH gene rearrangement in a primary cutaneous, large-cell (centroblastic and immunoblastic) B-cell lymphoma was analyzed using a micromanipulation/single-cell polymerase chain reaction technique. In all single B cells obtained from CD20-stained skin sections that gave a polymerase chain reaction product (eight of 27 in biopsy I), the same VHDJH rearrangement, consisting of DP-54-DIR1-JH3a genes, was detected, with no intraclonal nucleotide diversity. Comparison with the most closely related germline counterpart showed significantly altered complementarity determining gene regions as a result of somatic mutations, suggesting an antigen-driven selection and expansion ofthis particular B-cell clone. Interestingly, in a biopsy obtained from the patient 9 mo later, during disease progression (deep muscle infiltration), the lymphoma cells again contained the same VHDJH gene rearrangement (six of 18 in biopsy II) without any further somatic mutations. Therefore, it is suggested that the cutaneous lymphoma characterized throughout this study descended from postgerminal center B-cells.

The influence of EDTMP-concentration on the biodistribution of radio-lanthanides and 225-Ac in tumor-bearing mice. The ISOLDE Collaboration

High-resolution gamma spectroscopy was applied to measure simultaneously the biodistribution of carrier-free radionuclides of several lanthanides (141Ce, 145Sm, 149Gd, 167Tm) and 225Ac in tumor-bearing nude mice. Mixtures of the radiotracers were injected in solutions containing different concentrations of EDTMP (ethylenediaminetetramethylenephosphonic acid). The strong dependence of liver uptake on the ionic radius of the radio-lanthanides was confirmed for all tracers used. The ratios of radioactivity concentrated in tumour that concentrated in liver are strongly influenced by the EDTMP concentration, reaching values close to 10 for Tm, 3 for Sm, and 1 for Ac. The optimal EDTMP concentrations, giving highest tumor-to-liver ratios of enrichment, were between 1 and 10 mM for 100 microL injected volume for the animal model used in this experiment. In radionuclide therapy using EDTMP as ligands, close control of ligand concentration will be necessary.

Enhanced expression of T-cell activation and natural killer cell antigens indicates systemic anti-tumor response in early primary cutaneous T-cell lymphoma

Indolent, primary cutaneous T-cell lymphomas (CTCL) are characterized by hyper-proliferation of malignant T-helper cells in the skin with a favorable prognosis in the early stages. Cytotoxic T cells (CTLs) are believed to be of major importance for tumor surveillance, but there is not yet sufficient evidence for a systemic anti-tumor response in mycosis fungoides (MF). On the contrary, there are hints of systemic immunodepression. We wondered whether signs of a systemic anti-tumor response were demonstrable in peripheral blood of patients with MF and CD30+ pleomorphic T cell lymphoma. Using multiparameter flow cytometry, we investigated blood samples from 39 CTCL patients at different stages and compared them with those from patients with psoriasis, atopic dermatitis, and healthy volunteers. In CTCL patients, an elevated number of lymphocytes expressing natural killer cell markers were found, as well as considerable T-cell activation, indicated by increased percentages of T cells expressing HLA-DR, IL-2 receptor alpha-chain, and transferrin receptor. The CD8+ T cells, which were the most strongly activated T-cell subset, were of polyclonal origin, as shown by their usage of different T-cell receptor families. The enhanced expression of activation antigens was associated with an increased proportion of CD8+ T cells with high expression of the adhesion molecule LFA-1, demonstrating the capacity for migration of these cells. These CD8+ effector cells are suspected to be CTLs and may be responsible for the favorable prognosis of indolent, primary CTCL. Interestingly, a stage-dependent decrease in T-cell activation antigen expression was observed, suggesting the development of a lack in tumor surveillance in advanced MF stages. Further investigations are necessary to verify whether any of the parameters determined are of predictive value for prognosis and response to therapy in CTCL.

VH genes expressed in peripheral blood IgE-producing B cells from patients with atopic dermatitis

In this study we analysed the VH genes expressed in IgE-producing peripheral B cells in two patients with severe atopic dermatitis. We found a diverse antibody repertoire containing V(H) genes of five different VH families, no VH2 and 7 genes, with no biased usage of one particular VH gene family. Some VH germ-line segments were found to be used several times within the epsilon transcripts (V3-23, V3-30). Comparison of the IgE-encoding VH genes with the respective germ-line elements revealed the expression of nearly germ-line identical as well as somatically mutated VH genes. In these latter VH genes base substitutions were distributed over both complementarity determining and framework regions. Because of the similarities between the IgE committed B cell repertoire in atopic patients and the peripheral B cell repertoire in non-atopic individuals we conclude that the atopic VH gene repertoire probably reflects the result of an increased class switch of polyclonal B cells, including virgin and mature B cells, in response to a Th2 cytokine profile.

Increase of melanocytic nevus counts in children during 5 years of follow-up and analysis of associated factors

OBJECTIVES

To investigate nevus development in childhood and to examine causative related factors such as pigment phenotype and the role of sun exposure in the development of melanocytic nevi.

DESIGN AND PARTICIPANTS

Nevus counts were performed in kindergarteners (n = 866) before the age of 7 years and again 5 years later (n = 377). Eligible for analysis were 357 children who were examined twice. Possible related factors were searched for by standardized interviews with parents.

RESULTS

The mean number of nevi measuring 1 mm or more was 9 in the first examination and the number measuring 2 mm or more, 4. Five years later, the mean number of nevi measuring 1 mm or more was 40 and the number measuring 2 mm or more was 16. Children with poor sun tolerance had statistically significant more nevi (relative risk, 3.7;95% confidence interval, 1.9-7.2). The presence of freckles was a strong predictor for a high increase of melanocytic nevi (relative risk, 2.1; 95% confidence interval, 1.3-3.3). The number of days per year with intensive solar exposure was an independent prognostic factor. The relative risk for the development of melanocytic nevi was increased by a factor of 1.6 in children who had more than 21 days of intensive sun exposure per year (95% confidence interval, 1.0-2.5).

CONCLUSION

The development of melanocytic nevi in childhood is strongly related to characteristics of pigmentation associated with poor sun tolerance. In addition, we found evidence for the influence of UV radiation on the number of acquired melanocytic nevi in childhood.

Technical problems arising from the use of the immunoblot for determination of the reactivity of natural antibodies with different lipopolysaccharides (LPS)

Natural polyreactive antibodies (NPAB) appear to play an important role in the first-line defence against invading bacteria. The major constituent of the outer membrane of Gram-negative bacteria is the lipopolysaccharide (LPS). Therefore, reactivity against this structure could be of importance in protecting the organism from the harmful effects of LPS. Immunoblotting has become a common method to verify the specificity of antigen antibody interactions. Various immunoblot techniques for testing the reactivity of monoclonal antibodies with LPS have been published using nitrocellulose and detergent-free blocking buffer systems. These methods are not suitable for the investigation of NPABs due to the broad reactivity and a high background staining which gives rise to interpretational difficulties. In the present study we demonstrate an immunoblot technique using polyvinylidene difluoride (PVDF) membranes and a detergent-containing buffer system which permits to detect LPS reactivity of NPABs. The polyreactive monoclonal human antibody CB03 used was screened for lipid A/LPS reactivity in ELISA experiments. The binding was confirmed in the described blot system and depends on the membranes and blocking agents used. The use of nitrocellulose versus PVDF was also tested for monospecific anti-LPS antibodies and the latter can be recommended due to the production of stronger reaction patterns without any background staining.

[Characterization of chick embryo fibroblast culture--overview of its effectiveness as a hybridoma cell]

The use of culture supernatant (added in a final concentration of 25% v/v) from chicken embryonal fibroblasts (CEF) for stimulation of established hybridoma cell lines has been shown. The proliferative effect on hybridoma cells from different origins was heatproof and was possible with a reduced serum part (FCS) in the culture medium. After a chromatografic separation the supernatant sections were tested and the positive effect was much lower in comparison to the total conditioned media.

Cell cluster formation during up-scaling of a human-mouse heterohybridoma producing a polyspecific human IgM antibody

Up- and downstream processing of human monoclonal IgM is known to bring about problems with respect to clone stability and quantity of antibodies produced. A human B cell hybridoma producing a natural polyreactive IgM antibody (CB03) was adapted to growth in serum-free medium and scaled-up using a hollow fiber bioreactor system. The process of fermentation has been carried out continuously over a period of 4 months. In comparison to stationary culture conditions in the presence of 10% fetal calf serum, antibody concentrations in hollow fiber bioreactor supernatants were found to be significantly increased. Semicontinuously harvested supernatants contained up to 400 mg/liter immunoreactive IgM antibody. During the last weeks of fermentation, a markedly reduced number of viable cells was observed, whereas antibody production seemed to remain stable. Furthermore, we detected formation of cell clusters in the fermentor system. These clusters carried IgM on the surface and secreted immunoreactive IgM antibodies. Clusters were found to represent fusions of hybridoma cells using electron microscopy. Cluster formation was accompanied by decreased glucose consumption and lactate accumulation and was not seen during growth of other human hybridomas. We discuss these results in the content of the polyreactive binding properties of this particular antibody.

Expression of monovalent fragments derived from a human IgM autoantibody in E. coli. The input of the somatically mutated CDR1/CDR2 and of the CDR3 into antigen binding specificity

A hybridoma producing a polyspecific human monoclonal IgM antibody (named CB03) has been derived from a fusion of mouse myeloma cells with human spleen lymphocytes obtained from an autoimmune patient suffering from chronic idiopathic thrombocytopenia. The antibody was found to be encoded by somatically mutated VHI and VlambdaIII genes. To study the input of mutated complementarity regions (CDRs) into antibody specificity, the antigen binding features of the purified complete IgM antibody were compared with (i) a Fab fragment by hot tryptic digestion and (ii) recombinant monovalent fragments expressed in E. coli. In detail, vectors were constructed encoding for (i) rFab03 and single chain Fv03 fragments containing the VH and VL genes connected by a linker sequence, (ii) scFc1.1. fragments containing the VH germline equivalent and the CB03 wild-type CDR3 region, and (iii) scFv fragments containing the CDR1 and CDR2 in germline configuration and the CDR3 expressed in the CB253 human fetal B cell hybridoma producing a polyspecific IgM antibody. The expression vectors contained at the 3' end either a (His)6 motif allowing purification on Ni(2+)-agarose or a c-myc tag for specifically detecting the expression products by a murine monoclonal antibody. Western blotting and ELISA analyses of the expression products indicate: (i) recombinant Fab fragments were found in the bacterial periplasm in extremely low amounts (1-10 micrograms from 1 litre bacterial culture), (ii) scFv fragments were obtained in suitable amounts from bacterial periplasm (800-1000 micrograms/l), (iii) the monovalent recombinant fragments as well as the Fab obtained by tryptic digestion reflected the polyspecific antigen binding features of the complete IgM antibody, but did bind to the antigens with much lower affinity, and (iv) the CDR3 was found to be of critical importance for the antigen binding pattern of this particular IgM. We discuss the expression of recombinant scFv fragments in E. coli as a suitable method in studying the role of the somatic mutation in autoantibody generation.

Tumour cell binding by a human monoclonal IgM antibody from the spleen of a non-tumour-associated patient is due to somatic mutations in the VH gene

Recently we described the occurrence of B cells producing polyspecific natural IgM with anti-tumour specificity in the spleen of non-tumour-bearing individuals as well as in fetal organisms. Immunoprecipitation and 2-D electrophoresis showed the binding of such antibodies to a 55-kD (pI 6.0) membrane surface glycoprotein. In vitro cultivation of human cancer cell lines in the presence of the purified IgM antibodies resulted in growth inhibition and complement-mediated cell lysis. Furthermore, the antibodies were shown to be able to induce MHC class I molecule expression on tumour cells. Because of this, a role for naturally occurring antibodies with anti-tumour specificity in preventing neoplasias had been suggested. We have constructed and expressed in Escherichia coli single-chain fragments (scFv: VH-linker-VL) derived from a polyspecific human monoclonal IgM autoantibody produced by a human x mouse heterohybridoma which was obtained from the spleen of an autoimmune patient. The mutated complementarity determining region (CDR) gene segments were replaced by the equivalent germ-line sequences and the CDR3 region was swapped for that from another polyspecific human natural antibody with no binding to tumours. Using these four scFv constructs for binding analyses and in vitro cultivation experiments we found: (i) scFv containing the mutated VH region of the original antibody were able to bind to tumour cells, to induce MHC class I molecule expression, and to inhibit tumour growth in a way similar to what had been described for the complete antibody; (ii) replacement of the mutated by the germ-line VH gene independently of the CDR3 to which it had been recombined, resulted in failure to bind to tumour cells. Nevertheless, other antigens (ssDNA, tetanus toxin) were still recognized, although with lower affinity. We discuss the significance of the replacement mutations in the VH gene CDRs, selected probably by B cell contact to an (auto)antigen, for generating a tumour binding capacity, not encoded by the germ-line gene.

A comparison of human and murine monoclonal IgGs specific for the P1.7 PorA protein of Neisseria meningitidis

Monoclonal human IgG SS269 reacts with Neisseria meningitidis expressing the P1.7 PorA protein and with linear peptides containing NGGAS, which accounts for the P1.7 specificity. Murine monoclonal antibody to P1.7 reacts with peptides containing the overlapping epitope, ASGQ. The human and murine antibodies have similar affinities. The low avidity human antibody is very inefficient at stimulating complement-mediated bactericidal killing while the high avidity murine antibody efficiently kills bacteria. However, efficient opsonophagocytosis was mediated even at low concentrations of the human antibody and in the absence of complement, suggesting that low avidity antibodies might be protective against disease.

Real-time biospecific interaction analysis of a natural human polyreactive monoclonal IgM antibody and its Fab and scFv fragments with several antigens

Surface plasmon resonance (SPR) was used to investigate the kinetics of interactions between the human monoclonal polyreactive IgM antibody CB03, its Fab as well as its single-chain variable fragment (scFv) and different antigens. From these experiments apparent binding constants were determined and compared with binding constants obtained by ELISA experiments. In SPR studies with the complete antibody, the polyreactivity of the CB03 antibody as derived from ELISA experiments was confirmed. Interaction of scFv with kappa casein and human myoglobin is strong evidence for the location of polyreactivity within the variable domains of the antibody. Apparent binding constants of the complete antibody to immobilized kappa casein (9.2 x 10(7) M-1) and to human myoglobin (1.6 x 10(7) M-1) are up to 83 times higher than those of Fab. The binding constants of the scFv to the above mentioned antigens are again about 10 times lower when compared with Fab, which is mainly due to the lower association rates of the complexes formed by the scFv.

Binding of natural human IgM auto-antibodies to human tumor cell lines and stimulated normal T lymphocytes

In a recent publication we described the binding of natural IgM antibodies derived from the human fetal B cell repertoire to the cell surface of some human tumor cells including colon carcinoma, small-cell lung cancer and B lymphoma lines [1]. Further analyses showed that a similar molecule was bound by the respective monoclonal human antibodies on the cell surface of polyclonally stimulated human CD3+ T cells, but is absent from unstimulated MNC. Both CD4+ and CD8+ stimulated cells were recognized. The molecule was found to be expressed together with lymphocyte activation markers (4F2, CD72, CD25). The membrane antigen expressed on both the activated T lymphocytes and tumor cells was characterized in a 2-D electrophoresis system: molecular weight 55-60 kDa, pI-approximately 6.0. Whereas the proliferation capacity of tumor cells was detected to be decreased significantly in the presence of the binding antibodies, no influence on [3H]thymidine uptake into stimulated T cells was found, suggesting different functional consequences of binding the respective antigen on malignant and normal cells. An interesting finding is the enhanced expression of major histocompatibility complex class I molecules on tumor cells incubated with human natural antibodies.