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Two major pathways of penile carcinogenesis are known: human papillomavirus (HPV)-induced penile cancer and HPV-negative cancers associated with chronic dermatoses. Therefore, modern measures for prevention of penile cancer may for example include prophylactic HPV vaccination. The resulting B‑cell-mediated immunity to HPV capsid proteins is effective protection against future HPV infections. Contrarily when treating existing HPV infections or HPV-associated cancers an antigen-specific T‑cell immunity is necessary. To date, screening and treatment of precancerous lesions to prevent penile cancer are not established in the German health care program and the highly expected therapeutic HPV vaccines are still on the horizon. In this article, we focus on possible strategies to prevent HPV-related penile cancer on different levels of carcinogenesis.

BACKGROUND: Antivenoms are mammalian immunoglobulins with the ability to neutralize snake venom components and to mitigate the progression of toxic effects. Immediate hypersensitivity to antivenoms often occurs during the first administration of these heterologous antibodies. A comparable clinical situation occurred after introduction of cetuximab, a chimeric mouse-human antibody, for cancer treatment. The carbohydrate epitope galactose-alpha-1,3-galactose, located on the Fab region of cetuximab, was identified as the target responsible for IgE reactivity. OBJECTIVE: To investigate whether serum IgE antibodies directed to the α-gal epitope are associated with hypersensitivity to equine antivenoms. METHODS: Antivenoms were screened for α-gal epitopes via immunoblot and in comparison with cetuximab and pork kidney by IgE reactivity assays. Basophil activation tests were used to investigate reactivity to antivenoms in samples from 20 patients with specific IgE antibodies to α-gal and 10 controls. Additional IgE detection, IgE inhibition, ImmunoCAP inhibition, and skin prick tests were performed using samples from selected patients. RESULTS: Both antivenoms and cetuximab induced positive skin prick test results in patients with sIgE to α-gal. Alpha-gal epitopes were detected by immunoblotting on antivenoms. Measurements of IgE reactivity and ImmunoCAP inhibition indicated that the antivenoms contained lower α-gal contents than cetuximab. Deglycosylation assays and IgE inhibition tests confirmed that IgE-mediated reactivity to antivenom is associated with α-gal. Antivenoms, pork kidney, and cetuximab activated basophils from patients with IgE to α-gal. CONCLUSION: Alpha-gal is a potential target of IgE-mediated reactivity to equine antivenom and a possible cause of the high incidence of hypersensitivity reactions during the first application of equine antivenom.

Vaccines are usually intended to prevent the spread of infectious diseases. Due to increasing knowledge about the immune system and its role in malignant disease, the development of therapeutic vaccines, which are intended to treat established tumors, has begun. For the induction of therapeutic immunity towards tumors, either tumor-specific or overexpressed antigens can be used. Tumor-specific antigens are mainly or exclusively expressed in tumors. It is assumed that they can thus be more easily recognized by the immune system than overexpressed antigens. Overexpressed antigens are expressed in both tumors and healthy tissues and therefore bear the risk of autoimmunity. In this review article, we discuss different approaches of therapeutic cancer vaccinations based on cells and on other drug substances. Moreover, we address the possibilities of authorizing cancer vaccines in the EU and in Germany.

Respiratory allergies of children and adolescents are an important issue in allergology. In parallel to increasing prevalence rates also research has rapidly been developing for the last 10 years. Today we can better understand complex systems to improve our diagnostic and therapeutic accuracy. In addition to medical history, skin-prick-testing and analysis of specific IgE to allergen extracts, component resolved diagnosis has gained importance in the last years. While being increasingly helpful in the diagnosis of insect-venom and food-allergies, component-based diagnosis can also improve the management of patients with respiratory allergies. Concerning different therapeutic approaches like allergen-avoidance or symptomatic therapy, specific immunotherapy (SIT) is one of the most interesting therapy-options, as it is still the only causal therapy available. After reasonable patient-selection and the selection of the right allergen and product, SIT has a very good risk/benefit-ration and can induce long-term immuno-tolerance to specific allergens.

The correlation between anaphylaxis after consumption of meat and the carbohydrate epitope galactose-α-1,3-galactose (α-Gal) was first described in oncologic patients treated with cetuximab. An association with tick bites and parasitosis is suspected. We report on a healthy patient who developed sudden anaphylactic reactions after the ingestion of meat. Serologic and skin tests confirmed sensitization to α-Gal. Avoiding the consumption of mammalian meat led to a complete absence of symptoms.

Anaphylaxis is a potentially life-threatening reaction and should be treated immediately. Diagnosis is made based on history and clinical features. However, measurement of sequential serum tryptase can provide additional clues and should be performed soon as possible. Referral to specialist allergy service is believed to reduce rate of recurrence. New specific in vitro techniques to indentify the triggering agent help optimize secondary preventive measures. Thus in vitro diagnosis plays an important, albeit complementary, role both in the acute and secondary phases facilitating a safe diagnosis and aiding in the overall management of the disease.

Pollinosis affects up to 25 % of the Swiss-population and increased substantially during the last century. Main causative pollens are birch and related pollens, ash pollen and grass pollen and to a lesser extent also mugwort. Diagnosis of Pollinosis is based on anamnesis, skin tests and determination of specific IgE in the serum. Treatment includes allergen avoidance, pharmacotherapy and allergen-specific immunotherapy (SIT). A proper patient and allergen extract selection, an ideally adapted application regimen and good patient-guidance as well as good compliance and treatment adherence are decisive for the success of the SIT. SCIT is the regimen of choice with well demonstrated efficacy, safety and long term effect. Nowadays SLIT is an additional complementary approach that mainly for grass pollen also offers good efficacy with good safety. Under such conditions immunotherapy leads to a benefit in more than 80 % of pollinosis-patients. Component-resolved diagnosis is a very useful and important step in more specific diagnosis. Several approaches studying changed application regimens and using molecular technologies to improve the efficacy of SIT are undergoing and will possibly substantially improve the efficacy, safety and acceptance of SIT.

Allergen-specific immunotherapy (SIT, desensitization) is applied monthly with subcutaneous injections (SCIT) or sublingually (SLIT) with droplets or tablets on a daily basis. Numerous immunological changes during SIT induce long-lasting tolerance. Efficacy has been demonstrated by a number of controlled studies for insect venom hypersensitivity (SCIT), allergic rhinoconjunctivitis (SCIT, SLIT particularly in grass pollen allergy), and allergic asthma (SCIT SLIT). SIT is indicated in children and adults with severe allergic reactions from insect venoms (e.g., bee, wasp) or cumbersome symptoms from pollen, house dust mites or mold allergens and proven immediated-type allergy. Contraindications must be considered individually. SIT is performed for 3 years, in case of venom allergy 3-5 years. Severe systemic reactions are rare after SCIT. After SLIT rather local allergic symptoms of short duration occur in the mouth and throat. At present, the number prescriptions for SIT has decreased due to inadequate reimbursement of allergy-related services (diagnostics, therapies, monitoring). In the future, inferior medical care of allergic patients in Germany is expected, who until now have benefited from the preventive effects of SIT (reduced risk of developing asthma and new allergic sensitizations).

Contact allergy is a skin disease that is caused by the reaction of the immune system to low molecular weight chemicals. A hallmark of contact allergens is their chemical reactivity, which is not exhibited by toxic irritants. Covalent binding of contact allergens to or complex formation with proteins is essential for the activation of the immune system. As a consequence antigenic epitopes are formed, which are recognized by contact allergen-specific T cells. The generation of effector and memory T cells causes the high antigen specificity and the repeated antigen-specific skin reaction of contact allergy. New findings reveal that the less specific reaction of the innate immune system to contact allergens closely resembles the reaction to an infection. Therefore, contact allergy can be viewed as an immunologic misunderstanding since the skin contact with chemical allergens is interpreted as an infection. The growing understanding of the molecular and cellular pathologic mechanisms of contact allergy can aid the development of specific therapies and of in vitro alternatives to animal testing for the identification of contact allergens.

Specific immunotherapy (SIT) of hymenoptera venom allergy, in particular, has become an example for the effectiveness of the treatment of IgE-mediated allergic diseases. In vitro diagnostic procedures and the measurement of serum tryptase for risk assessment are well-established in the process of diagnose finding and therapy preparation. For monitoring and validation of the effectiveness of the SIT, however, in vitro diagnostic procedures remain controversial. Potentially useful approaches include detection of specific IgE, specific IgG4, basophile activation - represented by the CD 63 expression - and the lymphocyte proliferation and its IL10 release. Preliminary data suggest that the latter method appear appropriate, whereas the detection of basophile activation did not produce definite results.

Although allergen-specific immunotherapy, which celebrates its 100-year anniversary this year, represents the only potentially corrective or curative therapy available in the field of allergy, this therapeutic option is rarely employed in patients with atopic dermatitis (AD), one of the most common chronic inflammatory skin diseases. The reason is the relatively low number of controlled studies and a high number of uncontrolled studies or case reports with quite heterogenous study designs focusing on the value of SIT in AD in the literature. However, since allergens clearly impact on the initiation and impairment of AD as well as flare-up of eczematous skin lesions in a subgroup of patients, selected patients might benefit from SIT as an additional therapeutic option. In this overview, we summarize the current data and provide a state-of-the-art view on the value of SIT in AD.

Allergic rhinitis (AR) is a common disease affecting 7-17% of children and adolescents who may suffer from a significantly impaired quality of life. For 100 years subcutaneous immunotherapy (SCIT) has been used to treat AR. If patients are chosen carefully, a clinically relevant reduction of seasonal symptoms and medication use can be achieved by SCIT. Serious adverse events are rarely encountered during adequately performed and monitored SCIT. Sublingual immunotherapy (SLIT) may be used as a less painful therapeutic alternative in children if the administration of SCIT is impossible. Recent controlled trials have shown that SLIT performed over one pollen season also ameliorates seasonal symptoms and reduces the need for concomitant medication. Local reactions are frequently encountered during SLIT whereas systemic and life-threatening adverse events under correctly performed SLIT have not been reported so far.

Animal dander is a common cause of allergic rhinitis and allergic asthma in patients. In this regard, cats and dogs represent major causes of allergy to animal dander. In first line, the therapeutic options include the elimination of the pet from the patient's home as a (secondary) preventive step. However, avoidance of temporary contacts or indirect exposure to cat dander is often difficult, since cat-allergens are widely distributed even in non-cat-keeping households. In general, conventional pharmacologic therapy does not thoroughly prevent allergic symptoms. Therefore, allergen-specific immunotherapy (SIT) represents an important therapeutic option. This article highlights the current standards and further developments of SIT for cat-allergic patients.

Drugs that are used in relation to allergen-specific immunotherapy (SIT) can be separated into pharmacoprophylaxis to avoid or decrease local and systemic adverse effects of SIT and in co-medications to treat other diseases. Regarding pharmacoprophylaxis, H1-antihistamines are able to reduce local and mild systemic, but not severe systemic side effects of SIT. H1-antihistamines do not attenuate the efficacy of SIT. Severe systemic side effects have been blocked in some cases with omalizumab; currently this agent can be used off-label during venom SIT. With regard to co-medication, the concomitant use of immunomodulating drugs during SIT must be individualized, if the effective profile and side effects of the immunomodulating drug are well-known and a negative effect on SIT is not likely. Recently approved immunosuppressive drugs and biologics are perceived critically due to their unpredictable immunologic effects. For forensic reasons cardioselective beta blockers should be discontinued although no data are available demonstrating adverse effects. If discontinuation is not justified and venom SIT is indicated, SIT can be performed while taking beta blockers. In contrast, ACE-inhibitors should always be stopped in patients with insect venom allergy.

Mycosis fungoides is the most common type of primary cutaneous lymphomas. The phenotype of the tumor cell corresponds to an effector/memory-type of helper T cell which, given its repertoire of homing receptors, is specialized for recirculation through the skin. In recent years genetic analyses have uncovered various chromosomal aberrations in the tumour cells of mycosis fungoides. Their relevance to the pathogenesis and clinical appearance are discussed in the following.

Approximately 25% of the population in industrialized countries suffer from IgE-associated Type-1 allergies. Multiple allergens can be tested simultaneously in one assay by using the protein microarray. Moreover, it is possible to measure more than one analytical parameter (e.g. allergen specific IgEs and IgGs) in one assay by combining different fluorescent markers with specific secondary antibodies. The different allergen components that are of interest are immobilized on a planar surface. By adding the patient's serum (a smaller amount of serum is needed compared to an immunoassay) the inherent IgE antibodies are captured by the corresponding allergens. Secondary fluorescing anti-IgE antibodies are added subsequently, thus the intensity of each spot on the microarray can be measured by using a biochipscanner. The detected signal is then transformed into quantitative data, which allows the classification of the patient's serum IgE level for the tested allergens. There are different approaches to reduce the complexity of the original extracts used for the production of the solid microarray phase to a smaller number of relevant pathogenic molecules. The component-resolved diagnosis still needs to be clinically validated, but initial studies show positive results concerning the sensitivity and specificity of the protein microarray. Protein microarrays are promising tools for screening diagnoses in allergic diseases as well as for the improvement of allergen-specific immunotherapy.

Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a rare IgE-dependent anaphylaxis to wheat, which occurs in sensitized people after ingestion of wheat followed by physical exercise. The major allergen associated with WDEIA is the wheat protein Omega (omega)-5-Gliadin (Tri a 19). We present three cases of WDEIA, demonstrating that this disease might be more frequent than anticipated and that neither prick test nor specific IgE to allergen extracts but rather detection of specific IgE against the recombinant protein Tri a 19 leads to diagnosis.

Two types of pluripotent stem cells form the origins of the cells of the innate and the adaptive immune system, as well as of essential elements of cooperating environments of this system. Pluripotent hematopoietic stem cells and their subordinated, sub-specialized progenitor cells develop, throughout life, the red cells, platelets, myeloid and lymphoid cells of this continuously regenerating cell system. Pluripotent mesenchymal cells generate, among other types of differentiated cells, chondrocytes, epithelial cells, adipocytes and osteoblasts. These osteoblasts not only produce bone, the primary location for the hematopoietic cell development, but also directly interact with the hematopoietic stem and progenitor cells - and also with the mature, antigen-experienced memory types of lymphocytes which return after successful fights with antigens to the place of their origin. These interactions occur both by cell-cell contacts and cytokine-cytokine receptor recognitions in so-called"niches", and induce and guide the developments of the hematopoietic cells. These early phases of hematopoietic development are antigen-independent, because the cells of the adaptive system, the lymphocytes, have not yet made antigen-specific receptors. As soon as these cells express T-cell and B-cell receptors for antigen they are subjected to negative and positive selection pressures, first by auto-antigens in the primary lymphoid organs, then after maturation and migration to secondary lymphoid organs, also to external, foreign antigens. The repertoires of these lymphocytes expressing TcR and BcR adapt to the body's own, as well as external environmental, antigens. While cell-cell contacts with cooperating non-hematopoietic as well as hematopoietic cells, and cytokine-cytokine receptor interactions continue to induce the cellular responses resulting in proliferation, differentiation and/or programmed cell death (apoptosis) of the mature hematopoietic cells, such responses of lymphocytes are now dominated by the specific interactions of their antigen-specific receptors, TcRs or BrCs with antigens.

Allergic diseases show a broad variety of symptoms, depending on the type of allergen and the location where it interacts with the human body. Contact of allergens with the upper respiratory tract result in conjunctivitis or allergic rhinitis. Apart from antigenpresenting cells, T-cells do play an important role in this hypersensibility reaction. Due to the production and secretion of cytokines, T-lymphocytes induce and maintain the corresponding Th-immuneresponse. In addition to regulatory functions, T-cells have potential influence on the chronic progression of allergic inflammatory reactions of the nasal mucosa and are therefore interesting target cells for specific immunotherapy as well as corticosteroid treatment. This article shows the specific function of T-cells during allergic rhinitis and reveals the basics for understanding the mechanism of immunotherapy and chronification of inflammatory allergic diseases of the nasal mucosa.

The evolution of influenza viruses is increasingly pursued by molecular analyses that complement classical methods. The analyses focus on the two surface proteins hemagglutinin (HA) and neuraminidase (NA) which determine the viral antigenic profile. Influenza A(H3N2) viruses are exceptionally variable, so that usually at least two virus variants cocirculate at the same time. Together with influenza B viruses they caused approximately 90% of influenza virus infections in Germany during the last 12 seasons, while influenza A(H1N1) viruses only played a subordinate part. Unexpectedly, reassorted viruses of subtype A(H1N2) appeared during the seasons 2001/02 and 2002/03, but were isolated only rarely and gained no epidemiological significance. Furthermore, during the season 2001/02 influenza B viruses of the Victoria-lineage reappeared in Germany and other countries of the northern hemisphere after 10 years of absence. These viruses reassorted with the cocirculating Yamagata-like influenza B viruses, as could be seen by the appearance of viruses with a Victoria-like HA and a Yamagata-like NA.

IgG against extracellular subdomains of desmoglein 3 relates to clinical phenotype of pemphigus vulgaris., Der Pemphigus vulgaris (PV) ist eine durch intraepidermale Blasenbildung gekennzeichnete Autoimmundermatose, deren Pathogenese durch die Bildung von Immunglobulin G (IgG)-Autoantikörpern gegen das desmosomale Adhäsionsprotein, Desmoglein 3 (Dsg3), initiiert wird. Vorausgehende Studien zeigten, dass pathogene Autoantikörper vorwiegend konformationelle Epitope innerhalb der aminoterminalen Ektodomäne von Dsg3 erkennen. Zielsetzung der vorgelegten Arbeit war es, die IgG-Reaktivität der Seren eines klinisch gut charakterisierten Kollektivs an PV-Patienten gegen definierte Bereiche der extrazellulären Domäne von Dsg3 mittels Enzyme-Linked-Immunosorbent-Assay (ELISA) zu analysieren. Weitere Untersuchungen sollten zeigen, ob die Interaktion von PV-spezifischen Autoantikörpern mit Dsg3-Epitopen konformationsabhängig ist. Eine Voraussetzung für die Durchführung der ELISA-Experimente stellte die Produktion der gesamten Dsg3-Ektodomäne, Dsg3EC1-5, sowie ihrer fünf Subdomänen im Baculovirusexpessionssystem dar. Im Anschluss an die Klonierung der extrazellulären Dsg3-Domänen in einen geeigneten Baculovirustransfervektor erfolgte eine Kotransfektion mit Baculovirus-DNA in Insektenzellen. Nach Amplifizierung des Virus-Titers konnten die rekombinanten Proteine exprimiert und affinitätschromatographisch aufgereinigt werden. Insgesamt wurde eine Kohorte von 94 PV-Patienten, charakterisiert durch die jeweilige Krankheitsaktivität (akut (n=39), chronisch (n=42), Remission (n=13)) und den klinischen Phänotyp (mukosal (n=21), mukokutan (n=62), kutan (n=11)) untersucht. Darüber hinaus erfolgte die Analyse der Seren von zwei einzelnen PV-Patienten im Krankheitsverlauf. Innerhalb dieser Kohorte zeigten 91 % der Seren IgG-Reaktivität gegen die vollständige extrazelluläre Domäne, während jeweils 15 % bis 50 % der Autoantikörper auch einzelne Dsg3-Subdomänen erkannten. Die IgG-Autoantikörperantwort und IgG-Titer gegen die gesamte Dsg3-Ektodomäne korrelierten dabei mit der Krankheitsaktivi-tät der PV-Patienten. Weiterhin war die IgG-Reaktivität gegen den NH2-Terminus (Dsg3EC1) im Krankheitsverlauf einzelner PV-Patienten sowie gegen die extrazellulären Domänen Dsg3EC2, Dsg3EC3 und Dsg3EC4 in der Gesamtkohorte mit aktiven Krankheitsstadien des PV assoziiert. Die Autoantikörperantwort gegen die vier NH2-terminalen Subdomänen wies außerdem eine Assoziation mit einem schleimhautdomi-nanten Phänotyp auf. ELISA-Experimente mit nativen und denaturierten rekombinanten Dsg3-Proteinen demonstrierten, dass IgG-Autoantikörper aus PV-Seren sowohl mit konformationellen als auch mit nicht-konformationellen Epitopen innerhalb der Dsg3-Ektodomäne reagieren. Insgesamt zeigte die Auswertung der Autoantikörperprofile, dass die IgG-Reaktivität mit verschiedenen, vornehmlich aminoterminalen, nicht-konformationellen Epitopen hauptsächlich mit einem schleimhautdominanten Phänotyp assoziiert ist und mit der Krankheitsaktivität von PV-Patienten korreliert. Diese Resultate deuten darauf hin, dass während des „natürlichen Krankheitsverlaufs“ beim PV von der mukosalen zur vorwiegend kutanen Manifestation der Läsionen eine Verschiebung der Epitop-Erkennung von NH2-terminalen Bereichen zu anderen antigenen Determinanten der Dsg3-Ektodomäne stattfindet. Dieses Phänomen des „Epitope spreading“ wird auch bei anderen Autoimmunkrankheiten beobachtet. Die Verfügbarkeit der rekombinanten Dsg3-Proteine könnte, anhand einer detaillier-ten Charakterisierung des Dsg3-Autoantikörperprofils im ELISA, verfeinerte serologische Kriterien zur Erfassung der Krankheitsaktivität von PV-Patienten definieren.

Antibodies against citrullinated peptides are highly specific for rheumatoid arthritis. With second generation ELISA-kits, CCP-antibodies have a specificity of96 % and a sensitivity of 68 %. CCP-antibodies can be detected several years before the onset of clinical symptoms. They are, thus, ideally suited for the differential diagnosis between early forms of rheumatoid arthritis and other inflammatory arthritides. As CCP-antibodies are associated with aggressive and treatment resistant courses of rheumatoid arthritis, their high predictive value can be useful in therapeutic strategy decisions in order to verify early treatment with disease modifying drugs or biologicals in line with modern treatment approaches to start aggressive therapy early to prevent bone erosions. In contrast to their role in differential diagnosis and prediction of aggressive disease, however, CCP-antibodies are of no value in monitoring treatment as they do not change essentially over prolonged periods of time.

Psoriasis is a chronic inflammatory disease of the skin and the joints. Multiple factors contribute to the initiation of psoriasis. They include specific genetic characteristics such as major histocompatibility antigens and psoriasis susceptibility genes, as well as trigger factors, namely streptococcal infections. Today, psoriasis is considered as a T-lymphocyte mediated autoimmune disease, even though the putative autoantigen remains unknown. Bacterial proteins with similarity to structural proteins of keratinocytes are potential target antigens. As in other autoimmune diseases, inflammatory cytokines of the innate immune system initiate a cascade that activates inflammation locally in the skin, in the circulation and most likely also in lymph nodes. IFN-gamma-producing CD4+ Th1-lymphocytes seem to be of central importance in the pathogenesis of psoriasis as they critically influence differentiation and functioning of antigen presenting cells, mast cells, neutrophils and endothelial cells. This inflammatory cascade simultaneously provokes neoangiogenesis in the dermis and proliferation of keratinocytes. Based on this hypothesis, cytokines or anticytokine antibodies that either inhibit T-cell mediated inflammation or transform disease-inducing, pro-inflammatory Th1-lymphocytes into a phenotype with anti-inflammatory properties were tested in psoriasis. As both approaches improved psoriasis, they strongly support the current concept that views psoriasis as a Th1-lymphocyte mediated disease.

Allergic contact dermatitis (ACD) is a T-cell mediated, antigen-specific inflammatory response to repeated epicutaneous exposure to haptens. Two immunologically distinct sequential steps are required to produce the clinical picture of ACD. In the sensitization phase, naïve antigen-specific T cells are primed and differentiate into memory or effector T cells. In the elicitation phase, reapplication of the same hapten leads to local recruitment of hapten-specific T cells which are cytotoxic, release cytokines and recruit other inflammatory cells. These events lead to clinically visible tissue inflammation characterized by edema, erythema, scaling, and blistering. For the clinician, the effector phase is especially important, because sensitization is generally asymptomatic, whereas elicitation produces the clinical picture of ACD. Detailed knowledge about the mechanisms of the elicitation phase of ACD is needed in order to develop novel therapeutic approaches.

Patch testing is the standard method to identify allergic contact dermatitis. Simple, safe and accurate in vitro methods identifying contact allergies would offer both theoretical and practical advantages. Using the lymphocyte transformation test (LTT), allergen-specific lymphocytes central to the pathogenesis of Type IV allergies can be identified. Various studies have assessed the value of LTT in the diagnosis of contact allergies. The current assessment is that the test can be helpful in distinguishing between irritant and allergic reactions. LTT is especially useful in demonstrating drug allergies and can also be employed to prove sensitization to gases or toxic substances. At the present time, it is not an alternative for patch testing in daily practice.

The histopathological picture of many autoimmune bullous dermatoses is considered to be relatively characteristic. However, different entities may show similar histological findings. In addition, the picture depends on both the stage of the disease and prior treatment. Autoimmune bullous dermatoses are characterized by the production of autoantibodies to structural proteins of the skin. In most instances, the autoantigens have been identified and are available as recombinant proteins. Utilizing these recombinant forms, specific and sensitive assays have been developed for the detection of circulating autoantibodies in the serum. The detection of autoantibodies in skin or mucous membranes and/or serum is required for the diagnosis of autoimmune bullous dermatoses. The task of the dermatopathologist in the diagnostic process of autoimmune bullous dermatoses is to describe precisely the histopathological findings, to mention differential diagnoses and to recommend how these can be confirmed or excluded by immunopathological and immunoserological studies.

Regulatory T cells belong to a subset of T lymphocytes which suppress immune reactions in an antigen-specific fashion. Regulatory T cells play an important role in the prevention of autoimmune diseases. Ultraviolet (UV) radiation suppresses the immune system in antigen-specific fashion. This effect is mediated by UV-induced regulatory T cells. UV-induced regulatory T cells express CD4 and CD25 and upon activation release the immunosuppressive cytokine interleukin-10. Upon intravenous injection UV-induced regulatory T cells primarily migrate into the lymph nodes, explaining why they preferentially suppress sensitization. Recently, the development of regulatory T cells was demonstrated in an experimental model of photopheresis. The further characterisation of these cells will determine whether they can be applied in the future therapeutically with the ultimate aim to induce specific immunosuppression.

Today, multiparameter flow cytometry allows the simultaneous assessment of up to five surface and cytoplasmic antigens in different cell populations from peripheral blood and bone marrow samples. Due to the high efficiency of modern flow cytometers a comprehensive characterization is achieved within a short time. In the setting of diagnosing acute myeloid leukemias (AML) this method is used not only to subclassify AML and separate it from acute lymphoblastic and biphenotypic leukemias but also for the identification of leukemia-associated aberrant immunophenotypes (LAIPs). Since these LAIPs are defined individually for each patient, leukemic bone marrow cells can be detected during the course of treatment using the LAIP allowing the quantification of minimal residual disease (MRD) which is not detectable by cytomorphology. Due to its close correlation with the course of the disease and with the risk of relapse the MRD represents an important prognostic parameter which is increasingly used for stratification of therapy in clinical trials.

The identification of tumor antigens is crucial for the development of antigen-specific immunotherapies in cancer. Ideal target antigens for immunotherapies have a tumor specific expresssion pattern. Antigen expresssion in solid tumors is typically heterogenous. Therefore an effective immunotherapy should target several antigens simultaneously (polyvalent vaccine). Here we discuss strategies how tumor antigens can be identified and further analyzed as potential target antigens for active immunotherapy (cancer vaccine).

The only causal treatment that can be offered to allergic patients apart from allergen avoidance is specific immunotherapy. Its efficacy depends on the specific allergen the patient is allergic to, the quality of the extract, the total amount of allergen administered to the patient and the administration schedule.Our patient suffered from inhalative allergy to rat epithelium with severe rhinoconjunctivitis and bronchial asthma. She regularly worked with laboratory rats as a biologist. A job-shift was impossible for the patient, and so was allergen avoidance. We therefore decided to treat the patient with specific immunotherapy. Treatment was performed as in-patient procedure with Rush-Immunotherapy in dosage increase phase. Maintenance injections were administered as out-patient.As early as some months after induction of the therapy, the patient felt subjective symptom relief, blood samples taken revealed decrease of total IgE and specific IgE towards rat epithelium. Therapy was continued for 18 months, specific IgE against rat epithelium could not be detected any more. The patient does not claim any allergy symptoms when working in the rat laboratory any more.Even in unusual allergies, specific immunotherapy can be indicated. In our patient, specific immunotherapy to rat epithelium lead to complete symptom relief and enabled the patient to practise her profession without restraints.

Regulatory T cells modulate immune responses in different clinical settings. Here, we summarize the role of CD4(+)CD25(+) regulatory T cells in autoimmunity, transplantation, infectious diseases and tumor immunity.

Infections with hepatitis B (HBV) and hepatitis C virus (HCV) are worldwide one of the most frequent causes for chronic liver disease, liver cirrhosis and hepatocellular carcinoma. The mechanisms responsible for the elimination or the persistence of the virus are not well understood. The immunopathogenesis of HBV and HCV infection is primarily mediated by virus specific CD4+- and CD8+-T-cells. During acute infection a strong and multispecific T-cell response against different viral epitopes can be detected and is associated with the clearance of the virus. In case of viral persistence virus specific T-cells contribute to liver inflammation. In this article we summarize the current concepts about the role of the virus specific T-cell response in acute and chronic HBV and HCV infection.

The expression of B7-1/2 molecules in addition to TAA in APC significantly improves the generation of specific CTL in vitro. Moreover, human fibroblasts, usually devoid of APC capacity, can be engineered into effective APC upon infection with recVV encoding costimulatory molecules together with specific epitopes. The generation of artificial APC by infection of non professional APC with appropriately engineered recVV is a new concept that may be useful in the implementation of immunotherapy strategies.

Specific immunotherapy (SIT) represents the only specific treatment that can be offered to allergic patients apart from allergen avoidance. SIT has been widely used in pollen allergic rhinitis. Clinical efficacy has been demonstrated in several controlled clinical trials and depends on the specific allergen the individual patient is sensitive to, the quality and total amount of allergen applied, and the SIT schedule. In classic SIT, gradually increasing dosages of the allergen extract are injected subcutaneously. Several dosage schedules for subcutaneous SIT can be applied. In Cluster-SIT, 2 - 3 injections per day of treatment are given once a week during induction treatment.In this study, we investigated 64 patients (33 female, 31 male) from 18 to 54 years (26.9 +/- 5.1 years) in terms of side-effects of Cluster-SIT during induction treatment.The total amount of enlarged local reactions (grade 1) was n = 77 or 15.2 % of all injections. Of these, 68 (88 %) were classified as immediate reactions, 8 (11 %) were late phase reactions and 1 (1 %) was immediate as well as late phase reaction. Of all enlarged local reactions, 48 (62 %) were grade 1 reactions, 13 (17 %) were grade 2 reactions, 13 (17 %) were grade 3 reactions and 1 (1 %) was a grade 4 reaction. The total amount of systemic reactions was n = 22 or 4.3 % of all injections. Of these, 19 (86 %) were classified as immediate reactions, 3 (14 %) were delayed reactions. Of all systemic reactions, 18 (82 %) were grade 1 reactions and 4 (18 %) grade 2 reactions. Grade 3 or grade 4 reactions did not occur. There were no differences in gender or age regarding the occurrence of side effects (all p0.05).Frequency and severity of adverse side effects in Cluster-SIT correspond to those in other dosage schedules. On behalf of security aspects, Cluster-SIT could become an interesting alternative dosage schedule for dose increase during SIT. Furthermore, in Cluster-SIT with allergoids, induction treatment can be carried out in two treatment days of approximately 2.5 hours each.

Immunotherapy of cancer, autoimmune diseases, and chronic viral infections is still in the early stages of development. This review deals with new immunotherapeutic approaches against tumors. Until now, a variety of specific and unspecific immunostimulatory strategies have been applied with only modest clinical success. The molecular characterization of novel human tumor antigens and the increased understanding of the immunological pathways involved in tumor immunity, however, have paved the way for the design of promising gene-based cellular cancer immune vaccines. Tumor antigens are readily available now and several ways to deliver antigen have been developed. The most important and widely used approaches consist of whole-cell vaccines, dendritic cell-based immunotherapy, and peptide vaccines. Clinical trials have, in general, demonstrated the safety of such strategies. There is, however, an important lack of information regarding to the correlation of clinical responses and analysis of the antitumoral immune effectors. Recently, exciting new immunological techniques and tools have been developed which allow to characterize antigen specific T cells at a single-cell level. In future, tumor rejection antigens have to be identified using new approaches such as reverse immunology which can be targeted therapeutically. A better quality control of the different immunotherapeutic approaches is mandatory if used in patients and the different therapeutic modalities need to be compared directly. This standardization of immunotherapeutic clinical trials may allow the identification of patient sub-groups responding favourably to treatment. The precise definition of immune parameters will ultimately result in optimised therapeutic approaches. Finally, the identification of antigen specific T and B cells by new assessment tools may result in novel surrogate markers for clinical diagnostic immunotherapy.

Approximately 30% of patients suffering from severe haemophilia A develop antibodies against factor VIII (FVIII) neutralizing the effect of the pro-coagulant activity of intravenously injected FVIII as a complication of replacement therapy. Generally, various epitopes on the FVIII molecule are bound by these antibodies. The detailed structure of such epitopes is unknown. In this study epitopes on the FVIII molecule are identified using solid phase bound peptide arrays carrying the whole amino acid sequence of FVIII as small oligopeptides. The binding of FVIII antibodies by specific peptide sequences on the array indicates potential epitopes. FVIII antibodies of inhibitor patients and healthy blood donors are currently investigated by this method. Identified epitopes may lead to new concepts in therapy aiming at avoidance of inhibitor formation or improvement of inhibitor eradication. As participant of the 'haemophilia A' consortium dealing with genotype/phenotype correlation in haemophilia A we investigate, if the site or type of the mutation correlates with the epitopes, and if there is any relation between epitopes and clinical course. Furthermore, the influence of epitopes on therapeutical effects and the outcome of immune tolerance induction is under scrutiny.

Anti-Neutrophil Cytoplasmic Antibodies (ANCA) are a heterogenous group of autoantibodies with a broad spectrum of clinically associated diseases. The diagnostic value is established of Proteinase 3 (PR3)-ANCA for Wegener's granulomatosis (WG) as well as Myeloperoxidase (MPO)-ANCA for microscopic polyangiitis (MPA). Within the last 20 years these antibodies were subject of intensive studies and a growing body of evidence arose for a distinct role of ANCA in the pathogenesis of the ANCA associated vasculitides WG and MPA. Our current concept of whether ANCA directly or indirectly contribute to vascular damage (ANCA-Cytokine-Sequence-Theory) was mainly developed from in vitro studies. It is plausible and it is supported by data from clinical investigations as well as animal models. Nevertheless our knowledge of the etiological and pathogenetic pathways remains incomplete.

Mit durchflusszytometrischen und molekularbiologischen Verfahren wurden verschiedene Subpopulationen peripherer T-Lymphozyten bei gesunden Spendern und Nierentransplantatempfängern phänotypisch und funktionell untersucht. Wir fanden, dass eine T-Zell-Population, welche unter anderem die Oberflächenmarker LFA-1 und CD57 exprimierte, nicht aber CD28, terminale Effektorzellen enthielt. Wegen der bekannten Assoziation der Expansion CD57-positiver CD8-positiver T-Zellen mit einer Infektion mit dem Zytomegalievirus (CMV), wollten wir untersuchen, ob auch CMV-spezifische Effektorzellen darin enthalten waren. Um diesen möglichen Zusammenhang zwischen Phänotyp und Spezifität zu untersuchen, wurde ein bekanntes durchflusszytometrisches Verfahren zur Erfassung antigen-spezifischer CD4-T-Zellen so modifiziert, dass damit auch antigen-spezifische CD8-T-Zellen erfasst werden konnten. Dazu wurden frisch isolierte periphere mononukleäre Zellen in vitro mit löslichen Peptiden oder Peptidgemischen inkubiert (anstelle von Erregerlysaten oder Proteinantigenen wie im bekannten Verfahren), so dass durch direkte externe Beladung von MHC-I- und MHC-II- Molekülen nicht nur CD4- sondern auch CD8-T-Zellen stimuliert wurden. Anschließend konnten CD4 - und/oder CD8-positive T-Zellen nachgewiesen werden, in welchen es zur Synthese von Interferon-gamma gekommen war (intrazelluläre Färbung), wodurch diese Zellen als antigen-spezifisch identifiziert wurden. Diese Zellen konnten dann weiter phänotypisch analysiert werden. Unter Verwendung bekannter CD8-T-Zellen-stimulierender CMV-Peptide konnte der Phänotyp CMV-spezifischer CD8-T-Zellen untersucht werden, wobei sich zeigte, dass das CD57-positive Subset tatsächlich den gößeren Teil der CMV-spezifischen CD8 T-Zellen enthielt. Andererseits konnte das neue Verfahren verwendet werden, um weitere Peptide zu identifizieren, welche eine T-Zellstimulation bewirkten (Epitopkartierung). In zwei von uns untersuchten Proteinen des CMV (pp65 und IE-1) wurden so mehrere neue CD4- und CD8-T-Zellepitope beschrieben. Die Vewendung komplexer Peptidgemische erlaubte darüber hinaus die Untersuchung der T-Zellantwort gegen ganze Proteine (repräsentiert durch die Gesamtheit aller denkbaren Epitope), was insbesondere für die Untersuchung von CD8-T-Zellen eine große Bereicherung darstellte und vom MHC-Typ unabhängig war. Wir verwendeten dieses neue Verfahren bisher zur Analyse und zum Monitoring der T-Zellantwort gegen bestimmte Erregerproteine oder -peptide (z.B. aus CMV oder HIV). Es eignet sich darüber hinaus auch zur Untersuchung der Immunantwort gegen Impfstoffe, welche zur Induktion von T-Zellen führen sollen. Using flow-cytometric and molecular-biology methods subpopulations of peripheral blood T-lymphocytes were examined in healthy donors and renal transplant recipients with respect to phenotype and function. We found that a T-cell population that expressed the surface markers LFA-1 and CD57 (among others), but not CD28, contained terminal effector cells. Because of the known association of an expansion of CD57-positive CD8-positive T-cells with an infection with Cytomegalovirus (CMV), we wanted to examine if CMV-specific effector cells were also contained in this subset. In order to investigate this association between phenotype and specificity, we modified a known flow-cytometric method for the detection of antigen-specific CD4 T-cells in such a way that antigen-specific CD8 T-cells could also be detected. For this purpose freshly isolated mononuclear cells were incubated in vitro with soluble peptides or peptide mixes (instead of pathogen lysates or protein antigens as used in the original method) so that following direct external loading of MHC-I and MHC-II molecules not only CD4 T-cells but also CD8-T-cells were stimulated. Subsequently, CD4 and/or CD8 T-cells that had synthesized Interferon-gamma (intracellular staining), which identified them as being antigen-specific, could be detected. These cells could then be analyzed with regard to phenotype. Using known CD8-T-cell stimulating CMV-peptides, the phenotype of CMV-specific CD8 T-cells could be analyzed. Thus it was demonstrated that the majority of CMV-specific CD8 T-cells was indeed contained in the CD57-positive subset. On the other hand, this new approach allowed the identification of additional peptides that stimulated T-cells (epitope mapping). In two CMV-proteins that we examined (pp65 and IE-1) several new CD4 and CD8-T-cell epitopes were described. The use of complex peptide mixes in this approach allowed the analysis of T-cell responses to complete proteins (represented by the entirety of all possible epitopes), which was a great benefit to the analysis of CD8 T-cells and independent of MHC-type. Until now, we have used this new method for the analysis and the monitoring of the T-cell response to specific pathogen proteins or peptides (e.g. from CMV or HIV). It is suitable, moreover, for the analysis of the immune response to vaccinations that aim at the induction of T-cells.

Specific immunotherapy comprises a special form of allergy treatment which consists of stepwise increasing doses of the allergen, given subcutaneously or orally with the aim to reprogram the specific immunity (from allergy to tolerance). This requires some experience and an exact allergological workup, since the main mistake in the treatment of this specific immunotherapy is the selection of unsuitable patients. The effectivity of specific immunotherapy is well documented for bee and wasp venom allergy, pollinosis and more and more also for asthma bronchiale. A type of unspecific passive immunotherapy is the injection of anti-IgE antibodies. However they block only soluble IgE and are not able to remove mast cell bound IgE. Thus, the allergic reactivity persists. Clinical studies have shown some efficacy in asthma as well as in pollinosis. However, at present it is unclear, whether this drug, which has to be given every two to four weeks in relatively high concentrations, is effective in patients with polysensitization (i.e. patients suffering from mite, fungal and pollen allergy) or is effective in patients which have manifestations of their allergy in different organs.