[The Concept of Immunogenic Cell Death in Antitumor Immunity]. / Význam imunogenní bunecné smrti v protinádorové imunite.

Cancer cell death can be immunogenic or nonimmunogenic depending on the initiating stimulus. The immunogenic characteristics of immunogenic cell death are mainly mediated by damage-associated molecular patterns represented by preapoptotic exposure of calreticulin and heat shock proteins (HSP70 and HSP90) from endoplasmic reticulum at the cell surface and active secretion of adenosintriphospate. Other damage-associated molecular patterns are produced in late stage apoptosis as high mobility group box 1 protein (HMGB1) into the extracellular milieu. Such signals operate on various receptors expressed by antigen presenting cells, mainly by population of dendritic cells, to stimulate the activation of antigen specific T-cell response. In this review, we describe the current known immunogenic cell death inducers and their potential to activate antitumor immune response.

[K-ras mutational status and tumour-infiltrating lymphocytes in human colon cancer: state of the art and future perspectives]. / K-ras mutace a nádory infiltrující lymfocyty u karcinomu kolon, soucasnost a výhledy.

INTRODUCTION: Nowadays, the prognosis of newly diagnosed colorectal cancer patients relies mostly on the tumour-node-metastasis (TNM) classification which is also a determining criterion for the indication of adjuvant oncological treatment. Currently, new prognostic and predictive biomarkers are sought after in order to more precisely define prognosis and better predict the benefits of adjuvant treatment in colorectal cancer. Besides several molecular biomarkers, such as mutations in the proto-oncogene K-ras, analyses of tumour-infiltrating lymphocytes have shown promising prognostic value. The aim of the study is to examine the correlations between K-ras mutational status and tumour-infiltrating immune cells in colon cancer patients with respect to colon cancer recurrence. MATERIAL AND METHODS: Formalin-fixed paraffin-embedded specimens were obtained from 44 patients with surgically resected colon cancer (R0 resection) treated between 2004 and 2009. K-ras mutational status was detected using PCR amplification of exon 1 followed by direct sequencing and K-ras StripAssay. Tumour-infiltrating immune cells were detected by immunofluorescence staining using monoclonal antibodies against CD3, CD8, FoxP3, CD1a and DC-LAMP. RESULTS: All 44 patients in our cohort underwent radical resection of colon cancer. In 16 patients the tumour relapsed (36.4%). K-ras mutations were found in 45.5% (n=20) of the primary carcinomas: 65% in codon 12 and 35% in codon 13. Although codon 13 K-ras mutations were associated with disease relapse, they were present in both disease-free and relapsed patients. However, disease-free and relapsed patients differed markedly in their patterns of tumour-infiltrating immune cells. There was a trend towards decreased density of tumour-infiltrating lymphocytes within the group of relapsed patients. In addition, relapsed patients with codon 13 mutations had markedly lower levels of tumour-infiltrating mature DC-LAMP+ dendritic cells and higher frequency of CD1a+ cells compared to disease-free patients. CONCLUSION: Colon cancer patients with low levels of tumour-infiltrating lymphocytes, a high CD1a+/DC-LAMP+ tumour-infiltrating DC ratio and a K-ras mutation in codon 13 are at a high risk of disease recurrence.

[Active cellular immunotherapy of ovarian cancer using dendritic cells]. / Aktivní bunecná imunoterapie karcinomu ovaria pomocí dendritických bunek.

OBJECTIVE: Overview and comparison of current results of studies dealing with the development and application of anti-cancer vaccines based on dendritic cells in ovarian cancer. DESIGN: Review. SETTING: Department of Obstetrics and Gynaecology Charles University, Prague, 2nd Faculty of Medicine and University Hospital Motol, Department of Immunology 2nd Faculty of Medicine and University Hospital Motol. SUMMARY: Ovarian carcinoma (OVCA) is highly sensitive to chemotherapy; however despite this results from treatment are fairly unsatisfactory. Bearing this in mind, it is important to look for new ways to better understand the immunological mechanisms which could affect reactivation of the disease. It is likely that new knowledge in the field of the immunology of ovarian carcinoma could improve monitoring of the disease and help to ameliorate prognosis of the disease. One strategy in development is creation of anti-OVCA vaccines. Theese vaccines are made by the fusion of dendritic cell (DC) and tumor cells or its parts (NA, peptides). DC are bone-marrow derived leukocytes that are critical in the initiation of T cell mediated immunity. DC are fused to patient-derived ovarian carcinoma cells. The fusion cells induces cytotoxic T cell against autologous OVCA cells.

Serum immunoglobulin free light chains in severe forms of atopic dermatitis.

An increase in immunoglobulin free light chains (FLC) was recently described in several pathological conditions, including asthma. FLC pathology is classically associated with monoclonal gammopathies. Its association with allergic disorders is surprising and unexplained. We therefore tested a cohort of children with severe atopic dermatitis (SCORAD 50-80) to determine the serum levels of free kappa and lambda chains, and correlated the results with clinical status and relevant laboratory markers. Seventy-three patients with severe forms of AD, all children from 3 months to 3 years of age and ninety healthy age-matched controls were included in the study. Light chains in sera were tested using the Freelite assay (Binding Site, Birmingham, UK). There were highly significant differences in both kappa (mean: 7.05 and 3.22 mg/l) and lambda (mean: 10.99 and 9.8 mg/l) serum levels between patients and controls, respectively (P < 0.0001). The kappa/lambda ratio in patients with allergy (mean: 0.64) was significantly higher than in controls (0.33) (P < 0.0001). We further observed significantly increased levels of FLC and their ratio in the group of patients with severe forms of AD in comparison to the group of patients with a resting stage of the disease or healthy controls (P < 0.05 and P < 0.0001, respectively). On the other hand, we could not confirm any association of FLC levels with age or total IgE levels. In conclusion, an increase in FLC reflects disease activity in children with severe atopic dermatitis. FLC might thus represent an additional diagnostic marker independent of total IgE levels.

Assessment of lymphocyte proliferation: CFSE kills dividing cells and modulates expression of activation markers.

The measurement of cell proliferation after mitogenic stimulation is an important parameter used in diagnosis of immunodeficiencies in clinical laboratory as well as in various fields of lymphocyte research. Recent methods try to overcome the radioactive assay using tritiated thymidine ((3)H) by flow-cytometric methods using different fluorochromes such as CFSE or even to substitute these direct methods by tracing the expression of cell-membrane activation markers associated with various steps of proliferation cycle. In our study we compared the (3)H assay with CFSE-staining method and expression of activation markers (CD69, HLA-DR, CD25, CD27, CD71, CD152, CD134 and CD195) on a sample of 128 consecutive patients and healthy controls evaluated in clinical laboratory. We also tested various concentrations of CFSE and its impact on proliferation activity and expression of activation markers. We found that CFSE in concentration from 37nM to 10microM decreases the proliferative capacity (expressed in cpm (3)H assay) due to the decreased viability of proliferating cells (measured as 7-AAD+) in concentration-dependent manner. Moreover, CFSE substantially modulates the expression of activation molecules (decreasing CD69, HLA-DR, CD25 the majority of examinated molecules). We found a good correlation between CFSE-staining method with (3)H assay, if CFSE low population is gated on CD3+ population (correlation coefficient 0.801), but only in samples with stimulation index (SI) higher then 25. In poorly proliferating samples (SI25) no correlation was found due to several false positive results in CFSE test. Statistically significant correlation between proliferation assessed as (3)H-thymidine incorporation and expression of activation markers was found in the case of CD25, CD27, CD38, CD152, CD71, still only in samples with higher proliferation activity (SI>25). No correlation was found with CD134, CD195, HLA-DR and CD69. We conclude that standard assay with (3)H-thymidine incorporation is unreplaceable assay in diagnosis of severe cellular immunodeficiencies as CFSE assay have high proportion of false positive results. Researchers tracing cell-membrane bound molecules on dividing cells stained by CFSE must take into account that CFSE may substantially modulate the expression of these markers and decrease the viability of stained cells.

Prolonged impairment of polymorphonuclear cells functions in one infant with transient zinc deficiency: a case report.

BACKGROUND: Zinc is an essential trace element for the immune system. The zinc deficiency diminishes antibody- and cell-mediated responses in man. Lymphopenia and thymic atrophy are usually the early hallmarks of zinc deficiency. Surprisingly, only scarce data are available about polymorphonuclear cells (PMNs) functions in infants with zinc deficiency. We present the results of immunological analyses in one infant with transient zinc deficiency due to decreased zinc concentration in mother milk resulting in severe lactogenic acrodermatitis enteropathica. MATERIAL/METHODS: Nine repeated examination of oxidative burst of PMNs and immunoglobulin levels using nitroblue tetrazolium dye test, chemiluminescence, flow cytometry and nephelometry were performed in the infant with severe zinc deficiency during 28 months period. RESULTS: The unusual prolonged but transient impairment of PMNs respiratory burst accompanied with hypogammaglobulinaemia developed since the age of 2.5 months. Dramatic improvement of the skin was observed within days with total resolution of skin lesions on the 9th day of zinc therapy, but decreased PMNs respiratory burst persisted until the age of 23 months. CONCLUSIONS: We conclude that zinc deficiency may lead to prolonged impairment of polymorphonuclear cells functions and hypogammaglobulinaemia.

[Auto- and alloreactivity of T lymphocytes in myelodysplastic syndrome]. / Auto- a aloreaktivita T lymfocytu u myelodysplastického syndromu.

BACKGROUND: Successful therapy with ATG and cyclosporine A in some myelodysplastic syndrome (MDS) patients led us to study the existence of T cells attacking autologous hemopoietic cells. In our study, we attempted to give the direct prove of autoreactive T cells in MDS (autoreactivity analysis). Simultaneously, we analysed the capacity of MDS patients to respond to allogeneic cells from unrelated individuals (alloreactivity analysis). METHODS AND RESULTS: Autoreactive lymphocytes directed against own bone marrow mononuclear cells were analysed using the modification of cell mediated cytotoxic reaction. With one exception we did not confirm the presence of autoreactive T cells among 10 patients examined. Analysis of alloreactivity was performed by means of standard cell mediated cytotoxic reaction and mixed lymphocyte reaction. Surprisingly, the cytotoxic response to allogeneic cells was negative in 11 MDS patients from 16 analysed. When comparing refractory anaemia (RA) and refractory anaemia with ring sideroblasts (RARS) patients, the proportion of negative results was higher in RA (78 %) than in RARS (40 %). In mixed lymphocyte reaction, the response of MDS cells to allogeneic cells of unrelated individual was positive in all tested patients. The preliminary testing of TNF and IFNgamma secretion examined in supernatants of effector cells showed impaired levels of both cytokines in RA and normal levels in RARS in accordance with the findings achieved in alloreactivity analysis. CONCLUSIONS: Autoreactive T cells were not found in MDS patients using our experimental arrangement. Analysis of alloreactivity showed the defect in effector--cytotoxic--phase of cell mediated cytotoxic reaction in the majority of MDS patients. The initial phase of this reaction represented in vitro by mixed lymphocyte reaction gave normal results. The possible reasons of disturbed alloreactivity and its relevance to immunity in MDS are commented in discussion.

Exposure to silica and risk of ANCA-associated vasculitis.

BACKGROUND: Exposure to silica dust is considered to be one of etiological factors of antineutrophil cytoplasmic antibodies (ANCA) -associated vasculitis (AAV). METHODS: Subjects exposed to silica dust in Central Bohemia and followed in the Department of Occupational Medicine, Charles University, were selected for study. A group of 86 men exposed to SiO2 for at least 5 years were examined. The association between occupational exposure to silica dust and ANCA positivity is analyzed. RESULTS: The subjects had a mean age of 66.7 years, and mean exposure to silica of 22.3 years. ANCA were detected significantly more frequently in patients group (17.1%; P-ANCA 18x, C-ANCA 3x) than in controls (n = 28, mean age 64.2 years, P-ANCA 1x, i.e., 3.6%). ANCA positivity was found less frequently (7.1%) in the group with history of SiO2 exposure without signs of pronounced silicosis, than in the group with simple (30.3%) or complicated silicosis (36.0%). Odds ratio for ANCA positivity and relative risk estimate in patients with silicosis were highly significant. Among possible predictor factors for ANCA positivity, silicosis and tuberculosis were relevant. No typical AAV was present among the patients. CONCLUSION: Long-term silica exposure may be one of the exogenous factors contributing to ANCA production, however, silica exposure alone, without typical silicosis, was not associated with ANCA positivity.

[Prevalence of hepatitis G virus infection (HGV) in intravenous immunoglobulin recipients in the Czech Republic]. / Výskyt infekce virem hepatitidy G (HGV) u pacientu lécených intravenózními imunoglobuliny v Ceské republice.

The prevalence of hepatitis G virus (HGV) in the serum of intravenous immunoglobulin (IVIG) recipients was studied and risk related to HGV positivity was considered. Although its pathogenicity is unclear, HGV is likely to cause liver disease or lymphoproliferation. Twenty (23%) of 86 tested MG patients were HGV RNA positive. Of the HGV positive patients, three (15%) showed mild elevation of liver enzymes and one (5%) was diagnosed with chronic lymphatic leukaemia prior to the institution of MG replacement. It can be concluded that the HGV prevalence among IVIG recipients is high but is not associated with signs of either liver disease or lymphoproliferation.

Effects of human plasma proteins on maturation of monocyte-derived dendritic cells.

Dendritic cells (DC) are a promising tool for vaccine therapy due to their unique properties as antigen presenting cells and their ability to prime naïve T cells. Increasing evidence suggests that maturation stage of DC critically influences the fate of the immune response. Generation of monocyte-derived DC for clinically applicable immunotherapy requires the use of well-defined components and stringent culture conditions. An alternative strategy is to use human autologous serum. However, its constituents are not stable and reflect the inflammatory condition of the donor. In order to investigate whether DC properties are influenced by proteins present in the plasma, we matured human monocyte-derived DC with four main plasma components: fibrinogen, fibronectin, plasminogen or C-reactive protein. These purified proteins were added at various concentrations on day 6 after the initial differentiation induced by IL-4 and GM-CSF. The maturation was assessed by phenotyping of maturation-associated marker (CD83) and co-stimulatory molecule CD86 as well as IL-12 production. Functional properties of DC were assessed by endocytic activity and mixed leukocyte culture. Our results indicate that fibrinogen had DC-maturation effect comparable to poly-I:C, TNF-alpha and PGE(2) as a positive control, but it failed to induce IL-12 production. The other plasma proteins had no effect on DC maturation. CRP at high concentration had rather inhibitory effect on DC induced lymphocyte function. We conclude that none of the tested plasma components and acute phase proteins sufficiently induce fully competent mature DC. This finding is important for the preparation of human DC-based vaccines supplemented by autologous sera.

[Glucocorticoids and their effect on dendritic cell function]. / Glukokortikoidy a jejich vliv na funkci dendritických bunek.

BACKGROUND: Dendritic cells represent the most effective antigen presenting cells and they are the only cell type capable of initiating the primary immune response. They use several sets of germ-line encoded receptors to differentiate between self and non-self and to detect the presence of danger signals. Danger signals are mainly represented by microbial pathogens but it can be also a necrotic or malignant cell. At various stages of their lifecycle dendritic cells play a key role in maintaining the peripheral tolerance towards self-antigens and in the initiation of an effective immune response. Glucocorticoids have been widely used in the treatment of autoimmune or inflammatory disorders and their immunosuppressive effect has been mainly attributed to the inhibition of lymphocytes functions. METHODS AND RESULTS: In this study, we discuss the effects of glucocorticoids on in vitro generated myeloid dendritic cells and on peripheral blood myeloid and plasmacytoid dendritic cells subsets. CONCLUSIONS: Experimental results point to the profound suppressive effect of glucocorticoids on the antigen presenting functions of dendritic cells and to contribute to better understanding of glucocorticoids-mediated immunosuppressive effect.

[Immunotherapy--perspectives in therapy of ovarian carcinomas]. / Imunoterapie--perspektivy vyuzití v lécbe ovariálních karcinomu.

OBJECTIVE: To summarise recent knowledge and clinical studies of immunotherapy in the treatment of malignant ovarian epithelial tumors. DESIGN: A literature review. SETTING: Department of Gynecology and Obstetrics, Charles University Prague, 2nd Medical Faculty, University Hospital Motol. Department of Immunology Charles University Prague, 2nd Medical Faculty, University Hospital Motol. ABSTRACT: Combination of surgery and chemotherapy has been the usual standard of therapeutic protocols in ovarian cancer patients. However, this therapy is still not sufficient to eliminate all of the tumour cells. Immunotherapy seems to be an effective approach in combination with surgery and chemotherapy. Immunotherapy includes three types of strategies: cytokine therapy, monoclonal antibody therapy and vaccine therapy, especially vaccines with dendritic cells. All of them are shortly reviewed in this article. IFNalpha, IFNgamma, IL-2, GM-CSF are examples of cytokine therapy. Representatives of monoclonal antibody therapy include trastuzumab (monoclonal antibody against HER-2/neu peptide, MAb B.43.13 (antibody against CA 125), or radiolabeled antibody--pemtumomab (90Yttrium-CC49). Cancer vaccination is used in experiments because it should be effective in presenting tumour cells as foreign cells to effector cells of the immune system. Otherwise, tumour cells are not usually recognised by the immune system as dangerous cells. The efficiency of immunotherapy depends on tumor size and previous therapy. It seems to be effective in potentiation of primary chemotherapy or as a consolidation treatment of minimal residual disease. Immunotherapy is still at the experimental level, but in the future it could be a useful part of protocols for the treatment of ovarian cancer.

Daily oral versus pulse intravenous cyclophosphamide in the therapy of ANCA-associated vasculitis--preliminary single center experience.

The aim of the multicentric randomized trial CYCLOPS is to optimize the treatment of induction of remission in patients with generalized, but not immediately life-threatening ANCA (antineutrophil cytoplasmic antibodies) -associated vasculitis. This will be achieved by reducing the dose of cyclophosphamide by administering it as intermittent pulses. The lower cumulative dose will be very probably accompanied with lower toxicity, whereas the effectivity should be comparable. We have enrolled 28 patients to the study. At present, 18 of them are suitable for evaluation. Our preliminary results show that pulse intermittent administration of cyclophosphamide is safer from the point of morbidity and mortality due to infectious complications. In our hands, this treatment modality does not seem to be less effective than the conventional daily oral cyclophosphamide. However, unambiguous results and treatment recommendations will not be available until the final evaluation of all patients enrolled in the trial.

[Primary biliary cirrhosis--specific anti-mitochondrial antibodies]. / Primární biliární cirhóza--specifické antimitochondriální protilátky.

UNLABELLED: Primary biliary cirrhosis is a chronic liver disease, characterized by the destruction of the epithelial cells of the sublobular, interlobular and septal bile ducts and with the development of cirrhosis. The presence of anti-mitochondrial antibodies against the subunits of mitochondrial 2-oxoacids dehydrogenases is characteristic for patients with primary biliary cirrhosis. The aim of this work was to study the effect of anti-mitochondrial antibodies upon activity of the isolated mitochondrial pyruvate dehydrogenase complex after the incubation with serum from patients with primary biliary cirrhosis. GROUP OF PATIENTS AND METHODS: The activity of the purified bovine pyruvate dehydrogenase complex was studied spectrophotometrically in presence of the serum (1: 1000) from five patients with primary biliary cirrhosis and from ten disease free controls. RESULTS: The activity of the pyruvate dehydrogenase was decreased after incubation with the serum from patients with primary biliary cirrhosis. No similar inhibitory effect was found after incubation with serum from controls. DISCUSSION: The inhibitory effect of the anti-mitochondrial antibodies upon activity of pyruvate dehydrogenase may broaden the spectrum of diagnostic methods in patients with primary biliary cirrhosis. Further investigations are necessary to assess the possible application of this method for monitoring of changes during the course of the disease and for assignation of the disease prognosis.

Antineutrophil cytoplasmic antibodies, anti-Saccharomyces cerevisiae antibodies, and specific IgE to food allergens in children with inflammatory bowel diseases.

Differential diagnosis between ulcerative colitis (UC) and Crohn's disease (CD) is difficult in the initial phases in pediatric patients with inflammatory bowel diseases (IBD). This study was performed to determine the significance of anti-neutrophil cytoplasmic antibodies (ANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) in IBD. ANCA were specified with regard to their antigenic specifity, significance to the diagnosis, and correlation of titer with the disease activity. The occurrence of food allergy was questioned, too. Serum samples from 44 children with UC (n = 23) or CD (n = 21) and from disease-control children (coeliac disease, n = 21) were analyzed for IgG ANCA, ANCA target antigens, IgA and IgG ASCA, and IgE to food allergens. Results show that ANCA occur more frequently in UC than in CD and disease-control (74, 24, and 10%, respectively). The presence of ANCA does not reflect disease activity. Antigenic specificity does not differ in any group. IgA-ASCA are found more often in patients with CD (76% versus 17% in UC). The testing for both ANCA and ASCA enabled clear-cut differential diagnosis between UC and CD based on the high specificity (ANCA+ ASCA- 92.5% for UC, ANCA- ASCA+ 93.2% for CD). Specific IgE to food allergens were found in 8.7, 14.3, and 23.8% of patients with UC, CD, and coeliac disease, respectively. We conclude that combined testing of ANCA and ASCA represents a valuable tool in the differential diagnosis between UC and CD in pediatric patients, minimizing invasive diagnostic procedures. Monitoring of ANCA, its specificity, and titer determination does not bring more information. Testing for specific IgE to food allergens may be considered in individual patients.

Lung transplantation for cystic fibrosis: immune system and autoimmunity.

BACKGROUND: In the current study we focused on changes in the immune parameters of patients with CF after lung transplantation (Tx), with particular emphasis on the interaction of the immune system, infection, the autoimmune phenomenon observed in some CF patients, and immunosuppression. MATERIAL AND METHODS: Seven transplant patients with CF were investigated, 3 men and 4 women; the average age at Tx was 24.2 years (20.2-32.3). The parameters of both humoral immunity (immunoglobulins, complement, CRP, antinuclear and antineutrophil cytoplasmic antibodies) and cellular immunity (T and B lymphocytes, NK cells) were traced. RESULTS: We observed marked initial hyperimmunoglobulinemia, with a sharp drop in immunoglobulin levels within 1 month after Tx. Positivity for antineutrophil cytoplasmic antibodies (ANCA) was found in 3 patients before Tx. A strong ANCA positivity persisted 2 months after Tx despite deep introductory immunosuppression. In one patient ANCA positivity, after a transient negative result at months 2 and 12 after Tx, reappeared one year after Tx. The Burkholderia cepacia infections found in 2 patients proved to be lethal. CONCLUSIONS: In our series of CF lung transplant recipients, we found Burkholderia cepacia infection to be a risk factor. The robust appearance of autoantibodies and their persistent positivity for many months despite deep immunosuppression is a remarkable feature observed in some CF patients.

Immunological investigation in children with juvenile chronic arthritis.

BACKGROUND: Immunological investigation is a part of the complex view on a child with juvenile chronic arthritis (JCA). We analyzed the data of a cohort of children with JCA in order to determine the real contribution of this investigation to their diagnosis and therapy. MATERIAL AND METHODS: We included the investigation of humoral immunity and autoantibodies of 78 children with JCA. 18 children completed investigation of both humoral and cellular immunity of paired peripheral blood (PB) and synovial fluid (SF). Humoral immunity consisted from immunoglobulins, complement, circulating immune complexes, rheumatoid factors, soluble HLA I. molecules and antinuclear and antineutrophil cytoplasmic antibodies. Cellular immunity included cytometric studies of CD3, CD4, CD8, CD16/CD56, CD19, CD20, 23, CD3 HLA DR+, CD45 RA, CD45 RO, alpha/beta and gamma/delta T cells. To observe the status of Th1/Th2 balance in children with JCA, the cytokines IL-4, IFN gamma, TNF alpha and IL-6 were measured in the tissue culture of the synovial cells. RESULTS: The parameters of humoral immunity in serum showed wide variability. We could not confirm particular changes specific for the forms or stage of the disease. ANCA were positive in 21 out of 78 children with JCA, 3 times both in PB and SF. More typical pattern could be followed in the comparison of PB and SF, with immunoglobulins and complement always found lower in SF than in PB. The cellular immunity was represented by the activation of lymphocytes mainly in SF, reverse ratio of CD45 RA and RO cells in PB and SF with marked predominance of memory T cells in the joint. High levels of sHLA in SF are the nonspecific marker of activation, the same is true for high levels of TNF alpha and IL 6 in SF cell culture supernatant. CONCLUSION: The described changes in immunological parameters of humoral and cellular immunity are not specific for JCA. In the individual cases they can contribute to the diagnosis and monitoring of the disease. The investigation of sHLA molecules and cytokine profile should be restricted only for research.

Biological properties of copolymer of 2-hydroxyethyl methacrylate with sulfopropyl methacrylate.

Interaction of organism with non-toxic implanted polymers depends on the physicochemical properties of the implant surface, which influence the adsorption of bioactive proteins and subsequently adhesion and growth of cells. The synthetic hydrogels are known as poorly adhesive surfaces. In this study we demonstrated the adsorption of albumin, fibrinogen, fibronectin, basic fibroblast growth factor, heparin-binding epidermal growth factor-like growth factor and epidermal growth factor to poly(2-hydroxyethyl methacrylate) (pHEMA) and copolymer of 2-hydroxyethyl methacrylate (HEMA) and potassium salt of 3-sulfopropyl methacrylate (SPMAK). The adhesion and growth of 3T3 cells and human keratinocytes on surface of these polymers was tested without and with pretreatment of polymers with heparin-binding epidermal growth factor-like growth factor. The adhesion of mixture of human granulocytes and monocytes to these surfaces was also tested. The strips of both polymers were subcutaneously and intracerebrally implanted into the rat and the extent of foreign body reaction and brain biocompatibility was evaluated. The results showed the extensive adsorption of basic fibroblast growth factor and heparin-binding epidermal growth factor-like growth factor to copolymer containing SPMAK. However the adhesion (and growth) of cells to this type of copolymers was very low. Preadsorption of human plasma to pHEMA clearly stimulated the leukocyte adhesion in contrary to copolymer containing SPMAK. The extent of foreign-body reaction was significantly higher against the pHEMA compared to tested copolymer p(HEMA-co-SPMAK). In conclusion, the tested copolymer was a poorly adhesive substrate that is only poorly recognized by the non-specific immunity, although the adsorption of basic growth factors to this substrate is highly significant. Both polymers were well tolerated by the brain tissue. The phenotype of surrounding neurons was more close to the control neurons in the brain tissue surrounding the p(HEMA-co-SPMAK) implants.