Irena Manolova

Role of dendritic cells in progression and clinical outcome of colon cancer.

PurposeThe dendritic cells (DCs) are key players in the initiation and regulation of immune responses including antitumor immunity. In the current study, we aimed to elucidate the role of different subtypes of DCs infiltrating the tumor stroma and invasive margin for tumor progression and survival of patients with colon cancer.MethodsThe presence of immature (CD1a- and S100 protein+) and mature (CD83- and HLA-DR+) DCs was evaluated by immunohistochemistry in tissue samples from 145 patients with colon cancer. Patients were dichotomized according to the number of DCs in the tumor stroma and invasive margin, and clinical, histological, and survival data were compared between the two groups of patients.ResultsThe number of the mature CD83+ DCs in the tumor stroma and in the invasive margin significantly correlated with the tumor stage: the lower level of infiltration was found in patients that have advanced tumor stage. The frequency of distant metastases was higher in patients who had lower numbers of immature CD1a+ DCs in tumor stroma and of CD83+ DCs in invasive margin. Patients showing a relatively high number of S100+ DCs in the tumor stroma and HLA-DR+ DCs in the invasive margin had a longer overall survival (p < 0.05). Patients with lower CD83+ DCs infiltration in invasive margin had worse prognosis after surgical therapy compared with those with higher CD83+ DCs infiltration (p = 0.0397).ConclusionsOur results demonstrate that the infiltration of colon cancer with DCs is related with tumor progression and patient prognosis, suggesting a central role for DCs in controlling local antitumor immunity.

Expression of ICAM-1, VCAM-1, E-selectin and TNF-α on the endothelium of femoral and iliac arteries in thromboangiitis obliterans

Immunohistochemical light and electron microscopical analysis of surgical biopsies obtained from femoral and iliac arteries of patients with thromboangiitis obliterans (TAO) were performed to investigate the presence of tumour necrosis factor-alpha (TNF-alpha) and expression of the endothelial cell adhesion molecules intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. Expression of ICAM-1, VCAM-1 and E-selectin was increased on endothelium and some inflammatory cells in the thickened intima in all TAO patients. Ultrastructural immunohistochemistry revealed contacts between mononuclear blood cells and ICAM-1-, and E-selectin-positive endothelial cells. These endothelial cells showed morphological signs of activation. The present data indicate that endothelial cells are activated in TAO and that vascular lesions are associated with TNF-alpha secretion by tissue-infiltrating inflammatory cells, ICAM-1-, VCAM-1- and E-selectin expression on endothelial cells and leukocyte adhesion via their ligands. The preferential expression of inducible adhesion molecules in microvessels and mononuclear inflammatory cells suggests that angiogenesis contributes to the persistence of the inflammatory process in TAO.

Decrease in intrahepatic CD56+ lymphocytes in gastric and colorectal cancer patients with liver metastases

Gulubova M, Manolova I, Kyurkchiev D, Julianov A, Altunkova I. Decrease in intrahepatic CD56+ lymphocytes in gastric and colorectal cancer patients with liver metastases. APMIS 2009; 117: 870–9.

Sarcoidosis and molecular mimicry--important etiopathogenetic aspects: current state and future directions.

SummarySarcoidosis is a disease of uncertainty in terms of its cause, presentation, and clinical course. The disease has a worldwide distribution and affects all ages, races, and both sex. Sarcoidosis of the skin may have an extremely heterogeneous clinical presentation, so that the definitions of ‘great imitator’ and ‘clinical chameleon’ have long been used.The factors that influence clinical picture and severity of the disease are probably linked to the etiopathogenesis of sarcoidosis, which continues to be shrouded in mystery.The current state of the art on the pathogenesis of sarcoidosis is that it is an immunological response in a genetically susceptible individual to an as-yet undefined antigenic stimulus. How exposure occurs in genetically predisposed patients is not completely clear, but the most likely explanation is that these agents or antigens are either inhaled into the lungs or enter through contact with the skin, as these are the common target organs that are constantly in contact with the environment. An autoimmune etiology of sarcoidosis could possibly occur through a process of molecular mimicry of infectious or other environmental antigens to host antigens. This could lead to a cross-mediated immune response and induction of autoimmune disease. This molecular mimicry may probably be responsible for the heterogeneous clinical presentations of the disease.Several investigations and studies have provided valuable evidence on the etiopathogenesis of sarcoidosis, which may lead to the future development of targeted and innovative treatment strategies. Nevertheless, we are still a long way from unravelling the underlying cause of this mysterious disease.ZusammenfassungDie Sarkoidose ist eine Erkrankung voll der Unsicherheiten in Bezug auf ihre Ursache, Präsentation und den klinischen Verlauf. Die Erkrankung kommt überall auf der Welt vor. Sie tritt in jedem Alter, bei allen Rassen bei Mann und Frau auf. Die Sarkoidose der Haut kann sich klinisch extrem unterschiedlich präsentieren – seit Langem wird sie daher auch als „Großer Nachahmer“ und „klinisches Chamäleon“ bezeichnet.Die Faktoren, die das klinische Bild und die Schwere der Erkrankung beeinflussen, sind wahrscheinlich mit der Ätiopathogenese der Erkrankung verbunden. Diese sind aber auch heute noch immer ungeklärt. Die aktuelle Lehrmeinung besagt, dass die Sarkoidose eine immunologische Antwort auf einen bis jetzt undefinierten antigenen Reiz in einem – genetisch bedingt – empfindlichen Individuum darstellt. Wie es zur Exposition der genetisch prädisponierten Patienten kommt ist nicht ganz klar. Die wahrscheinlichste Erklärung ist, dass diese Substanzen, beziehungsweise Antigene entweder über die Lungen inhaliert werden oder durch Kontakt mit der Haut in den Körper eintreten. Haut und Lunge sind die am häufigsten befallenen Zielorgane, die dauernd mit der Umwelt in Kontakt stehen. Eine autoimmune Ätiologie der Sarkoidose könnte möglicherweise durch einen Prozess der molekularen Mimikrie von infektiösen oder anderen Antigenen aus der Umwelt auf Wirt Antigene erklärt werden. Dadurch könnte es zu einer „cross mediated“ Immunantwort und Auslösung einer autoimmunen Erkrankung kommen. Diese molekulare Mimikrie kann möglicherweise für die unterschiedliche klinische Präsentation der Erkrankung verantwortlich sein.Verschiedene Untersuchungen und Studien haben wertvolle Evidenz in Bezug auf die Ätiopathogenese der Sarkoidose geliefert. Dadurch könnte es in der Zukunft zur Entwicklung von zielgerichteten neuen Behandlungsstrategien kommen. Heute sind wir allerdings trotz allem noch weit entfernt von der Entwirrung der zugrunde liegenden Ursache dieser geheimnisvollen Krankheit.

Adhesion molecules in chronic ulcerative colitis

Background and aimsThe adhesion molecule expression in colonic mucosa is pivotal for transition from quiescent to active stage of ulcerative colitis (UC). The aim of the present study is to reveal the adhesion molecule profile of colonic mucosa in the active stage of UC and in remission.Materials and methodsBiopsy specimens obtained from 14 patients with UC (seven with active disease and seven with UC in remission) and from seven controls were used. Immunohistochemistry was performed with antibodies against ICAM-1, VCAM-1, E-selectin, LFA-1, Mac-1, and VLA-4.ResultsIn controls, slight ICAM-1 positivity was observed on thety endothelium of blood vessels of the mucosal and submucosal layer and only single ICAM-1-, Mac-1-, and LFA-1-positive cells were found. In all patients with UC, the endothelium of venules in the edematous mucosal and submucosal layers was ICAM-1-, VCAM-1-, and E-selectin-positive. Numerous ICAM-1- and LFA-1-positive and less VCAM-1-, Mac-1-, and VLA-4-positive inflammatory cells were detected in mucous layers of acute UC. In specimens of UC in remission, the inflammatory cells positive for the studied adhesion molecules were significantly less in number in the mucosa and submucosa (p < 0.05).ConclusionsBased on the increased expression of ICAM-1, VCAM-1, and their ligands LFA-1 and VLA-4 in patients with UC, we can conclude that these adhesion molecules play a key role in the adherence of lymphocytes and macrophages to endothelial cells maintaining the chronic inflammation. Presence of E-selectin on endothelial cells of venules could be a sign of relapse after remission in UC.

Serum levels of transforming growth factor-β1 (TGF-β1) in patients with systemic lupus erythematosus and Hashimoto's thyroiditis

BACKGROUND Transforming growth factor-β1 (TGF-β1) exerts broad anti-inflammatory and immunosuppressive effects and plays a key role in self-tolerance. Complete knockout of TGF-β1 in mice results in autoimmunity and multi-organ inflammatory syndrome. The aim of the present study was to determine TGF-β1 serum levels in healthy individuals and in patients with typical systemic or organ-specific autoimmune disorders such as systemic lupus erythematosus (SLE) and Hashimotos thyroiditis (HT) in an attempt to elucidate the importance of TGF-β1 in human autoimmunity. PATIENTS AND METHODS Serum concentrations of TGF-β1 were determined using an enzyme-linked immunosorbent assay in a group of 53 patients with SLE (87% women) and 123 with HT (95% women). Results were compared with those from 66 healthy controls (HC; 80% women). RESULTS Significantly lower levels of serum TGF-β1 were found in patients with SLE and HT than those found in HC (mean ± SD: SLE: 8.7 ± 2.5 ng/mL; HT: 18.74 ± 8.2 ng/mL; HC: 33.01 ± 2.4.8 ng/mL; SLE versus HC: p<0.001; HT versus HC: p<0.001). Also, serum levels of TGF-β1 were significantly lower in patients with SLE compared to patients with HT (p<0.001). The serum levels TGF-β1 were significantly higher in men than in women in the HC group (63.4 ± 28.1 ng/mL versus 26.6 ± 17.5 ng/mL, P<0.001), but were similar for men and women in both patients groups (p>0.05). CONCLUSIONS Our data demonstrate that altered TGF-β1 levels are associated with the presence of autoimmune disorders, and that TGF-β1 concentrations seem to be more profoundly depressed in systemic autoimmune diseases than in autoimmune thyroid disorders. Autoimmunity may have been triggered as a result of a decreased immunosuppressive effect induced by depressed TGF-β1 levels in patients with SLE and Hashimotos thyroiditis.

Prognostic significance of CD83 positive tumor-infiltrating dendritic cells and expression of TGF-beta 1 in human gastric cancer.

BACKGROUND/AIMS In this study we analyzed the significance of CD1a and CD83 positive tumor infiltrating dendritic cells (TIDCs) and the expression of TGF-β1 in gastric cancer tissue, and their relationship with disease progression and prognosis of patients. METHODOLOGY The immunohistochemical expression of CD1a, CD83 and TGF-β1, was evaluated in 55 patients with gastric cancer and followed-up for five years. RESULTS We found tumor infiltration with CD1a and CD83 positive DCs in all 55 cases and cytoplasmic TGF-β1 immunoreactivity in tumor cells in 76.4% of cases. TGF-β1 expression correlated to low CD83 positive DCs in 100% of the samples (χ2=7.66; p=0.022). Low CD83 positive DCs in tumor border (χ2=15.38; p<0.001) was also observed in 100% of tumors with TGF-β1 expression. The number of CD1a and CD83 positive TIDCs in the tumor border was inversely correlated with positive lymph node metastases (χ2=6.64; p=0.036 and χ2=6.44; p<0.04, respectively). Patients with a low number of tumor infiltrating CD83 positive DCs had shorter survival rates (p=0.022) and patients with TGF-β1 expression had a worse prognosis after surgical therapy (p=0.017). CONCLUSIONS Our results suggest that tumor infiltration with DCs may be of great importance in initiating the primary anti-tumor immune response. In patients with resectable gastric cancer, the grade of TIDCs and TGF-β1 expression could be a useful predictor of prognosis.

Antineutrophil cytoplasmic antibodies in Bulgarian patients with rheumatoid arthritis: characterization and clinical associations

ObjectiveThe aim of this study was to study the prevalence, subspecificities, and immunoglobulin (Ig)G subclass distribution of antineutrophil cytoplasmic antibodies (ANCA) in 90 Bulgarian patients with rheumatoid arthritis (RA) and to investigate the clinical associations of ANCA in these patients.MethodsThe ANCA were detected by indirect immunofluorescence, while antigen specificities were determined by enzyme-linked immunosorbent assay (ELISA) directed against myeloperoxidase (MPO), proteinase 3 (PR3), bactericidal/permeability-increasing protein (BPI), lactoferrin (LF), leukocyte elastase (LE), and cathepsin G (CG). The IgG subclass reactivity of antibodies to BPI and LF was measured.ResultsAntineutrophil cytoplasmic antibodies were found in 18 RA patients. Only a P-ANCA fluorescence pattern was seen. Six sera reacted to BPI, five to LF, one to MPO, one to PR3, and one to CG by ELISA testing. Immunoglobulin-G1 was the predominant subclass for LF-ANCA, whereas IgG1/3 contributed mainly to BPI-ANCA. Compared to P-ANCA-negative RA patients, the P-ANCA-positive patients exhibited significantly higher inflammatory activity, as estimated by disease activity score, C-reactive protein, erythrocyte sedimentation rate, and higher levels of IgM rheumatoid factor.ConclusionTwenty percent of Bulgarian patients with RA have P-ANCA in their sera. These antibodies are directed against variable antigen specificities, while ANCA positivity in RA reflects disease and inflammatory activity.

Prognostic significance of HER2/neu expression in gastric cancer.

ZusammenfassungHINTERGRUND: Das Magenkarzinom ist in vielen Ländern noch immer die häufigste Neoplasie. Deshalb werden neben den als Prognose Marker bekannten klinisch pathologischen Faktoren neue unabhängige Parameter untersucht. Immer mehr Daten deuten darauf hin, dass bei Patienten mit dieser Krebserkrankung eine Expression von HER2/neu eine Rolle spielt. Solide Untersuchungen haben gezeigt, dass diese Expression mit einem schlechten Ausgang und einem aggressiveren Erkrankungsverlauf korreliert ist. PATIENTEN UND METHODEN: Fünfzig Magenkarzinom Gewebsproben wurden mittels Immunhistochemie auf das Vorliegen von HER2/neu untersucht. Es wurde versucht zu erheben, ob ein Zusammenhang zwischen einer HER2/neu Expression und klinisch pathologischen Parametern der Patienten besteht. Außerdem wurde eine eventuelle prognostische Bedeutung einer HER2/neu Expression wurden erhoben. ERGEBNISSE: Eine HER2/neu Membranfärbung wurde bei 7 (14 %) Fällen gefunden. Die Patienten mit einer Her2/neu Überexpression hatten im Vergleich zu den HER2/neu negativen Patienten eine schlechtere Prognose nach chirurgischer Therapie (p = 0.001, Log-rank test). Es wurde kein Zusammenhang zwischen einer HER2/neu Expression und klinisch-pathologischen Parametern gefunden. SCHLUSSFOLGERUNGEN: Unsere Ergebnisse zeigen, dass eine immunhistochemisch erhobene HER2/neu Überexpression mit der Überlebensrate der Patienten korreliert. Dies fassen wir als ein gutes indirektes Maß der Qualität unserer Untersuchungen auf. Die Methode könnte daher einen Wert als prognostischer Marker beim Magenkrebs haben.SummaryBACKGROUND: Gastric cancer is still the most prevalent neoplasia in many countries. Therefore, besides the clinicopathological factors known to be prognostic markers, new independent parameters are being investigated. There is mounting evidence of the role of HER2/neu expression in patients with this type of cancer, and it has been solidly correlated to poor outcomes and a more aggressive disease. PATIENTS AND METHODS: Fifty gastric cancer tissue specimens were examined for the presence of HER2/neu by immunohistochemistry. The correlation between HER2/neu expression and patient clinicopathological parameters was evaluated and the prognostic significance of HER2/neu expression was assessed. RESULTS: HER2/neu membrane staining was detectable in 7 (14.0%) cases. The patients with HER2/neu overexpression had worse prognosis after surgical therapy compared with those without expression of HER2/neu (p = 0.001, Log-rank test). No relationship was found between HER2/neu expression and other clinicopathological parameters. CONCLUSIONS: Using immunohistochemistry, our data showed that the association between HER2/neu overexpression and patient survival provides a good indirect validation for quality of this investigation and it may act as a prognostic parameter in gastric cancer.

Association of single nucleotide polymorphism at position −308 of the tumor necrosis factor-alpha gene with ankylosing spondylitis and rheumatoid arthritis

In this study, we analyzed the putative association between the −308 G/A polymorphism in the promoter region of the tumor necrosis factor (TNF) α gene (rs1800629) and chronic inflammatory arthritis in the Bulgarian population. A case-control study was carried out on 58 patients with ankylosing spondylitis (AS), 108 rheumatoid arthritis (RA) patients and 177 healthy subjects. −308 G/A TNF-α genotypes of patients and controls were determined by restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR). No significant association between the rs1800629 polymorphism and RA risk in the study cohort was observed. However, there were significant differences in the genotype and allele frequencies of the −308 G/A TNF-α polymorphism between AS patients and the healthy subjects. In logistic regression analysis, the presence of the TNF-α −308A allele in the genotype (AA + AG vs. GG) was associated with a 3.298 times lower risk of developing AS. In addition, in AS, there were associations for age at disease onset (<29 years; odds ratio (OR) = 0.222), disease severity (Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score > 4; OR = 0.152) and response to anti-TNF treatment (OR = 2.25) under a dominant model (AA + AG vs. GG). In conclusion, our results suggested that the promoter polymorphism −308 G/A in the TNF-α gene had no significant effect on RA development, but could play a role in AS development and in determining the age of disease onset, disease severity and therapeutic outcome of AS in the Bulgarian patients who participated in our study.