Evaluation of rabbit auricular chondrocyte isolation and growth parameters in cell culture

Auricular cartilage is an attractive potential source of cells for many tissue engineering applications. However, there are several requirements that have to be fulfilled in order to develop a suitable tissue engineered implant. Animal experiments serve as important tools for validating novel concepts of cartilage regeneration; therefore rabbit auricular chondrocytes were studied. Various parameters including isolation procedures, passage number, rate of proliferation and gene expression profile for major extracellular matrix components were evaluated in order to assess the potential use of elastic chondrocytes for tissue engineering. Chondrocytes were isolated from rabbit ear cartilage and grown in monolayer cultures over four passages. Yields of harvested cells and proliferation were analysed from the digestion step to the fourth passage, and changes in phenotype were monitored. The proliferation capacity of cell cultures decreased during cultivation and was accompanied by enlargement of cells, this phenomenon being especially evident in the third and fourth passages. The expression of cartilage specific genes for collagen type II, aggrecan and cartilage non-specific collagen type I was determined. The mRNA levels for all three genes were obviously lower in the primo culture than immediately after isolation. During subsequent cultivation the expression of collagen type II decreased further, while there were only slight changes in expression of aggrecan and collagen type I. This study provides a valuable basis for testing of different tissue engineering applications in rabbit model, where auricular chondrocytes are considered as cell source.

Phagocytic functions of salivary neutrophils in oral mucous membrane diseases

BACKGROUND AND PURPOSE

Phagocytic functions of salivary polymorphonuclear neutrophils (sPMNs) have not been comprehensively studied in patients with oral mucous membrane diseases, although available data suggest the role of immunity in their pathogenesis.

SUBJECTS AND METHODS

Phagocytic functions of sPMN were determined in 15 patients with acute recurrent aphthous ulceration (RAU), 11 patients with oral lichen planus (OLP) and 20 healthy volunteers. In healthy subjects, the same parameters were also determined in peripheral blood polymorphonuclear neutrophils (bPMNs). Phagocytic activity (proportion of ingesting cells, PA), ingestion ability (number of ingested targets per 100 phagocytes, IA) and intracellular microbicidity (proportion of killed targets, IM) of PMNs separated from peripheral blood and the whole unstimulated saliva were determined by acridine orange method with living yeast cells as targets.

RESULTS

Salivary PMNs in healthy individuals showed significant reduction in PA (33% vs. 76%; P < 0.009) and IA (0.47% vs. 2.93%; P < 0.009) and significant increase in IM (12.0% vs. 5.5%; P = 0.011) in comparison with bPMNs. In RAU patients, reduced PA (27% vs. 37%; P = 0.035) and IA (0.25% vs. 0.47%; P = 0.05) were detected, while in OLP patients enhanced IM was detected (12% vs. 19%; P = 0.033) in comparison with healthy controls.

CONCLUSION

Salivary PMNs present functional features distinct from those in peripheral blood. Some phagocytic functions of sPMNs are reduced in RAU and enhanced in OLP, indicating their role in pathogenesis or reflecting clinical changes in these conditions.

Immunogenicity of dendritic cells pulsed with cartilage derived soluble alloantigens

Investigation of allo- and autoreactivity of cartilage components is useful not only for the potential allogeneneic transplantation but also for the treatment of tissue specific degenerative autoimmune diseases. We generated dendritic cells (DCs) to study articular cartilage immunogenicity, by using human peripheral blood mononuclear cells. Dendritic cells are extremely efficient antigen-presenting cells that initiate and modulate T-cell dependant immune responses. After isolation by density centrifugation, GM-CSF and IL-4 were added to adherent mononuclear cells. After 7 days of cultivation the cells in cell culture were: HLA-DR+, CD86+, CD14-, CD80-, CD83, CD19-, CD56-, CD3-. Dendritic cells were then pulsed with a supernatant taken from primary monolayer cell cultures of human allogeneic chondrocytes. The stimulating capacity of antigen-pulsed DCs was measured in a classical proliferation assay using tritium labelled thymidine as a marker of mitosis. Proliferative responses were significantly strong but became much stronger when DCs were concomitantly incubated with soluble antigens and human recombinant TNF-alpha and used subsequently as stimulators. Although TNF-alpha positively influenced the stimulating capacity of pulsed DCs, we were unable to detect major differences in expression of specific DCs' phenotype markers assessed by flow cytometry in the absence or presence of this cytokine.

Determination of optimal transport conditions for biopsies of human articular cartilage as well as for suspensions of cultured chondrocytes used in autologous transplantation

Autologous transplantation of chondrocytes is currently being promoted as a novel approach for the treatment of deep cartilage lesions. Briefly, the method involves enzyme-mediated release of chondrocytes from cartilage biopsies, the expansion of cells by in vitro cultivation and their re-implantation into the defect. The success of this technique depends on many factors including transport conditions for both, cartilage biopsies from the operating hall to the laboratory and the return transport of final suspension of cultured chondrocytes. To determine the extent of cellular damage in biopsies, chondrocytes were enzymatically isolated following a few days of tissue preservation in different tissue culture media. The proportion of dead cells was assessed by Trypan blue staining and counting. The viability was not dependant of the type of the medium used and remained approximately 50% in all samples, even after 72 h. To develop optimal conditions for transport of final chondrocyte suspension, isolated cells were firstly grown in monolayer cultures. Cell suspensions in media with different additives were injected into special glass containers used for the transport and left at 4 degrees C or 25 degrees C for up to 3 days. During this period every 24 h the samples were taken and viability as well as apoptosis levels were assessed. Viability of cells in suspensions at 25 degrees C decreased significantly and became inadequate already after 48 h. In contrast to that, the proportion of viable cells at 4 degrees C remained above 80% even after 48 h. In the majority of the samples, culture medium containing serum and vitamin C provided the best conditions for long-term preservation of chondrocytes.

Protein synthesis of human articular chondrocytes cultured in vitro for autologous transplantation

Chondrocytes in hyaline cartilage produce typical matrix proteins, the most abundant of them being collagen type II and aggrecan. Chondrocytes in monolayer cell culture dedifferentiate and gain fibroblastic phenotype. The cells gradually start to produce collagen type I while the production of collagen type II and aggrecan decreases. Transplantation of autologous chondrocytes cultured in vitro is used for treatment of aseptic articular cartilage lesions. For this purpose, cartilage biopsy is taken and isolated cells are subsequently proliferated in a monolayer cell culture. When implanted, the cells start to produce specific cartilaginous matrix that fills the defect. Prior to surgical procedure the cells can also be cryopreserved for longer periods of time after reaching appropriate numbers. We tested the influence of cultivation time and number of continuous culture passages as well as the influence of cryopreservation on the matrix protein synthesis of human articular chondrocytes. The ability of dedifferentiated chondrocytes to redifferentiate has been monitored by measuring matrix protein synthesis of the cells, re-seeded in agarose suspension culture. The results obtained show progressive dedifferentiation during monolayer cell culture procedures, facilitated by cryopreservation. Successful redifferentiation of cells re-seeded in suspension cultures was observed regardless of the previous level of chondrocyte dediferentiation.

In vitro functional tests for evaluation of stimulating capacity of cultured human dendritic cells

Basic functional test for evaluation of in vitro cultured human dendritic cells (DC) is primary allogeneic one-way mixed lymphocyte reaction (MLR). In this way, one can evaluate stimulating capacity, which is a basic characteristic of DC. The proliferation of cells is measured through incorporation of 3H-thymidine. Normally proliferation is measured at days 5-7. We studied kinetics of proliferative responses initiated with different stimulating cell suspensions to evaluate differences and possibly reduce time needed to perform this test. Gradual increase in response from days 1 to 7 and a significant difference from controls (peripheral blood mononuclear cells) seen from day 4 was noted if macrophages were used as stimulators. A consistently higher proliferation, compared to controls, was always found already on day 2 when mature DC were used as stimulators. The reaction peaked 2 to 3 days earlier and was also more than two times more intense. This maximal and significantly higher response, consistently seen already after 48 hours, allows us to confirm the presence of mature DC in stimulating suspensions much earlier than previously.

Transfection of mammalian cells by the methods of receptor mediated gene transfer and particle bombardment

The efficacy of currently developed methods for gene transfer into mammalian cells depends primarily on the transfection technique, and also on the type of targeted cells. Considering the importance of gene transfer in the creation of gene therapies, our study was aimed at the assessment of transfection capacity of receptor mediated gene transfer method (RMGT), and method of particle bombardment (helios gene gun system--HGG) in different normal and malignant mammalian cells ex vivo. In addition, the HGG was also assessed for its ability to transfect tumor cells of subcutaneous (s.c.) tumors in C57Bl/6 mice in vivo. Using RMGT an average ex vivo transfection rate of 35.7%, and 20.4% was achieved in malignant melanoma B-16, and human breast adenocarcinoma MCF7, respectively. However, in normal fibroblast L929 cells the transfection by RMGT succeeded only in 2.1% of the cells. On the other hand, the transfection efficacy of HGG was comparable in both malignant cell lines resulting in an average gene transfer to 9.6% of B-16 and 10.5% of MCF7 cells, while only 3.9% of normal fibroblasts were successfully transfected. Application of HGG for an in vivo gene transfer into s.c. B-16 melanoma tumors in C57Bl/6 mice resulted in a successful but limited transfection of the epithelium as well as of the superficially sited tumor cells. Taking into consideration both methods, RMGT is more appropriate for ex vivo transfection of cells, under the condition that target cells express a specific receptor for the molecule attached to the carrier. On the other hand, HGG is not complicated to use, no requirements for specific structures on target cells are necessary (potentially usable in different cells), and it has applicability in direct in vivo transfection processes.

Oscillatory behavior of critical amplitudes of the Gaussian model on a hierarchical structure

We studied oscillatory behavior of critical amplitudes for the Gaussian model on a hierarchical structure presented by a modified Sierpinski gasket lattice. This model is known to display nonstandard critical behavior on the lattice under study. The leading singular behavior of the correlation length xi near the critical coupling K=K(c) is modulated by a function which is periodic in ln/ln(K(c)-K)/. We have also shown that the common finite-size scaling hypothesis, according to which for a finite system at criticality xi should be of the order of the size of the system, is not applicable in this case. As a consequence of this, the exact form of the leading singular behavior of xi differs from the one described earlier (which was based on the finite-size scaling assumption).

Changing the stereotypes of "counsellors"

Stereotypes, as a relatively inflexible form of cognitive organization, serve in the organization of personal experience. They are relatively difficult to change and take a relatively long time. In our study we have tried to examine whether some traditional stereotypes of "counsellors" have altered during more than three years of work by members of the Croatian Psychiatrists Association with displaced persons in a camp in Zagreb. The statistical analysis of the information indicated that stereotypes have changed and in such a way that positive stereotypes have become more positive while the negative have become less negative among those displaced persons who had continued counseling from psychiatrists, psychologists and social workers from our Association. In the long-term, these results can be considered even more positive than the actual process of psychological assistance because the change in stereotypes is likely to be reflected in a larger number of future clients and through future generations.

Human interleukin-2 (IL-2) expressed by transfected mammalian cells

cDNA for human interleukin-2 (IL-2) was cloned into the pRc/RSV vector for expression in animal cells. Baby hamster kidney (BHK-21) cells and Chinese hamster ovary (CHO) cells were transfected several times using calcium phosphate and electroporation methods with the construct pRc/RSV SIGIL2. Different transfection efficiencies were obtained. The biological test on CTLL-2 (mouse cytotoxic lymphocytes) showed that the kinetics of cell proliferation were different from those of rIL-2 (recombinant IL-2) expressed in bacteria and in BHK cells. When high concentrations of rIL-2 were applied, an inhibitory effect on CTLL-2 was observed when bacterial product was used, whilst rBHK interleukin caused no inhibition. Recombinant BHK IL2 induced a slower response of CTLL-2 cells at the beginning of the cultivation, however, prolonged activity was detected at the later stage of the experiment.

[Effect of organic solvents on gynaecological diseases]

The authors studied the effect of working conditions and harmful organic solvents on the frequency of gynaecological diseases and menstrual disorders in 138 women. The experimental group consisted of 88 women exposed to evaporation and increased concentrations of organic solvents, and the control group was composed of 50 employees without any harmful effect of these noxa. It was found that adnexitis and dysmenorrhea were more frequent in the experimental group than in the control group, and that the statistical difference was significant (p<0.01). However, the frequency of gynaecological diseases, such as haemorrhages and menstrual disorders, were almost the same in both groups, without a statistically significant difference (p>0.05).

[Effect of noise on birth capability]

The author studied the effect of noise on birth in 132 women working in the metal industry at Valjevo. Of this number 82 women were exposed to increased noise and were included in the experimental group, and 50 employees, working out of the noisy premises, made the control group. A statistically significant number of natural miscarriages, maintenance of pregnancy and small weight of preterm babies, was recorded in the experimental group in comparison to the control group. It is concluded that the noise provoked a constant stress with utero-placental and foeto-placental circulatory disorders resulting in unwanted abortions.

[Effect of heavy metals on symptoms of high-risk pregnancy]

The authors studied the effect of working conditions and harmful organic solvents on the frequency of gynaecological diseases and menstrual disorders in 138 women. The experimental group consisted of 88 women exposed to evaporation and increased concentrations of organic solvents, and the control group was composed of 50 employees without any harmful effect of these noxa. It was found that adnexitis and dysmenorrhea were more frequent in the experimental group than in the control group, and that the statistical difference was significant (p<0.05). However, the frequency of gynaecological diseases, such as haemorrhages and menstrual disorders, were almost the same in both groups, without a statistically significant difference (p>0.05).

Pulmonary pathohistological changes in mice in experimental infection with Pneumocystis carinii

The infection Pneumocystis carinii was activated in mice of closely related BALBc/AnNCR, C57BL/6 and DBA/2 strains applying various doses of hydro-cortisone-acetate in combination with hypoprotein or complete food. The males of all investigated strains showed to be more sensitive than the females and the longest survived mice of C57BL/6 strain. The character of pathohistological pulmonary changes varied depending on the duration of survival. The mature cyst forms of Pneumocystis carinii were confirmed in tissue applying GMS and PAP method, and intracystic sporozoite by GMS staining.

[Distribution of p27 and gp70 feline leukemia virus antigens in various tissues]

Application of immunocytochemical methods (DP, IP, PAP, APAAP and IP-IP) has confirmed the existence of p27 and gp70 feline leukosis viral antigens (FeLV) in various tissues of 22 cats. Both viral antigens were found in bone marrow stem cells, but p27 antigens were mostly found in epithelial cells of intestinal crypts. In splenic T-lymphocytes and mediastinal lymph nodes the predominance of gp70 antigens in FeLV was confirmed, while the tropism of leukosis viruses in the lung was inclined to epithelial cells of bronchial glands where p27 antigens were dominant.

[Myxoma of the heart--clinical features, course and long term follow-up]

This study deals with clinical features, course and results of an eleven year follow-up of 22 patients with myxoma of the heart, 16 females and 6 males, mean age 48 years. Left atrial myxoma was found in 18 patients (82%) and right atrial myxoma in 4. The most frequent clinical features were fatigue in 64%, shortness of breath in 82%, systemic pulmonary embolism in 50% and prolonged fever in 27% of patients. On auscultation of the heart diastolic murmur was found in the mitral area in 36% and in tricuspid area in 14% of patients. The most helpful diagnostic noninvasive procedure was echocardiography which showed myxoma of the heart in all 22 patients. Left and right heart catheterisation studies were performed in 11 patients; in all patients with left atrial myxoma various degrees of pulmonary hypertension were found. Twenty one patients underwent open heart surgery; in twenty removal of myxoma was performed and in one concomitant mitral valve replacement was done. The mean follow-up of this group of patients was 6.2 years. All patients were asymptomatic and without clinical or echocardiographic signs of reccurrence.

[Motivation in patients for surgical treatment of prognathism using bimaxillary surgery]

A postoperative survey was conducted to evaluate the motivation of twenty three patients following surgical correction of mandibular prognathism. The operative technique of bimaxillary surgery was applied to all patients. The major reason for surgery was esthetics. Majority of patients were informed about surgery by their family dentists, and almost all of them were satisfied and stated that their expectations were fulfilled.

[Emphysema of the neck caused by a blast injury of the anterior oral cavity]

Parapharyngeal emphysema after blast injury of the oral cavity is very rare. It occurs as a consequence of sudden increase in the air pressure in the oropharynx which lacerates the buccogingival mucosa and enables entering of the air into the neck spaces. A possible mechanism of development and the way of penetration of the air into the parapharynx are explained.

Basal cell carcinoma treated with interferon

Human natural leukocytic interferon (HNLI) and recombinant interferon (rIFN) alpha 2c can be used in the therapy of basal cell carcinoma. Seventy-two patients were treated for 3 to 6 weeks with a single dose of 400,000 to 1,200,000 units (HNLI) and 2,000,000 to 5,000,000 units (rIFN alpha 2c). According to histopathologic and clinical findings, 52 patients were cured, and cancer cells were not found in the biopsy material taken after HNLI treatment for the second biopsy. In nine of 72 patients the cancer lesion was reduced 25% to 90%. In 11 patients it was not reduced or was reduced less than 25%. With rIFN alpha 2c therapy given five times per week for 4 weeks, histopathologic and clinical findings showed that five patients out of 12 were cured, and cancer cells were not found in the biopsy material taken after treatment. In seven patients out of 12 the cancer lesion was reduced 25% to 90%. Both types of interferons are effective in the treatment of basal cell carcinoma. Side effects were mild.

Interferon therapy for basal cell carcinoma and squamous cell carcinoma

Totally 161 basal cell and squamous cell carcinoma (BCC, SCC) patients were treated with human natural leucocytic interferon (HNLI) and recombinant IFN alpha 2c. After HNLI treatment, 61 out of 86 BCC patients and 29 out of 45 SCC patients were cured according to histopathologic and clinical findings. In 13 BCC and 13 SCC patients, the cancer lesion was reduced 25%-90%. After recombinant IFN alpha 2c treatment, 14 of 20 BCC patients and 4 of 10 SCC patients were cured according to histopathologic and clinical findings. In 6 BCC patients and 5 SCC patients the cancer lesion was reduced 25% to 90%. Both types of interferons are effective in the treatment of BCC and SCC patients. Local application of interferon stimulates immune reaction at the site of the tumor. There is a marked difference between the spontaneous macrophage activity and that induced by interferon. The interferon activated macrophages are significantly larger, the number of lysosomes and the density of macrophages is increased. In difficult locations intralesional therapy can be considered to avoid disfigurement of the patients with or without surgery.

Treatment of squamous cell carcinoma with interferon

Human natural leukocytic interferon and recombinant HulFN alpha 2c can be used in the therapy of squamous cell carcinoma. The duration of treatment was 3-6 weeks. A single dose was 400,000-5,000,000 units given weekly for 3-6 weeks. Clinically and histologically 19 of 32 patients were cured and tumor cells were not found in the material taken after interferon treatment for the second biopsy. In ten patients tumor size was reduced 25-90%, and in three patients tumor size was not reduced according to clinical findings. With recombinant HulFN alpha 2c therapy given 5 times per week for 4 weeks. Four of ten patients with similar tumors were cured clinically and histologically clinical findings. In five patients tumor size was reduced 25-90%, while in one patient there was no reduction in tumor size. Both types of interferons are effective in the treatment of squamous cell carcinoma. Side reactions were mild.

[Rhabdomyosarcomas in the field of otorhinolaryngology]

The authors describe rabdomyosarcoma of different location in two patients of different age. One patient, 51 years old, had rabdomyosarcoma located in the larynx. Its detection was late because its late manifestation. The patient refused the suggested treatment and the issue was lethal within the first year after the first symptoms had been discovered. The second patient was a child, aged 5, with rabdomyosarcoma on the upper lip. The tumour was detected relatively early and it was cured (operatively, by radiation and chemio-therapy). Unfortunately the result was lethal two years after the beginning of the illness.

Histopathologic and histoenzymatic observations in carcinomas treated with human leukocyte interferon

In this study histologic and histochemical examinations were performed on the bioptic material of 30 cases of head and neck tumors and 34 cases of uterocervical carcinomas after treatment with human leukocyte interferon (HLI). Particular attention was paid to the interaction between stromal and neoplastic cells as a possible host response to the treatment with interferon. In addition to tumor biopsies, regional lymph nodes were also examined microscopically. Stromal cells (macrophages, T and B lymphocytes, and granulocytes) were detected by enzyme-histochemical methods. Histologic and histochemical criteria for classification of tumor biopsies into five groups included the frequency, the cellular composition of peritumoral stroma, the grade of macrophage infiltration into the tumor (expressed quantitatively), and cytologic changes, followed by the regression of tumor. The overall appraisal of patients with cervical carcinoma based on histopathologic and chemical criteria showed the positive effect of HLI therapy in 70% of the cases; observations of head and neck carcinoma treated with HLI showed positive effects in 82% of the cases.

Influence of human leukocyte interferon on squamous cell carcinoma of uterine cervix: clinical, histological, and histochemical observations. III. Communication

Fifteen patients with invasive squamous cell carcinoma of the uterine cervix were treated with human leukocyte interferon (HLI). HLI was applied topically and i.m. to nine patients, and only topically to six. After therapy, surgical material was free from tumor cells in three patients, tumor cells were identified as invasive carcinoma in one patient and as CA in situ in two patients. Findings remained unchanged in nine patients. Tumor metastases in the lymph nodes were found in only one patient. The patients' overall response to therapy was assessed on the basis of stromal response, relation of tumor cells and macrophage activity, and the reactivity of lymph nodes.

Human leukocyte interferon in therapy of patients with urinary bladder papillomatosis, breast cancer, and melanoma

The authors report the result of local and parenteral applications of human leukocyte crude interferon in the therapy of eight patients with urinary bladder papillomatosis, four patients with breast cancer, and two patients with melanoma. The doses and effects of treatment are presented in tables. Clinical application of human leukocyte interferon (HLI) to these three types of malignant tumors has yielded encouraging results. The authors believe that investigations on HLI applications to some malignant tumors should continue because the results obtained indicate that interferon possesses not only an antiviral but also an antitumor activity.

Effect of interferon in therapy of skin and head and neck tumors

The clinical experimental model of HLI application in the therapy of skin and mucosal cancers of the head and neck has opened new prospects in HLI utilization. Based on clinical observations and research it may be concluded that HLI, if applied topically in the area of the tumor, may induce its disappearance or regression. If applied presurgically, it blocks the dispersion of neocytes during surgery. Also, HLI inhibits metastatic dissemination of malignant tumors and therefore might reduce the percentage of patients with recurrence, decreasing the chance of survival of any other primary tumor.

Application of human leucocyte interferon in patients with tumours of the head and neck

Local administration of crude human leucocyte interferon (HLI) produced substantial or total remission in patients with cancers of the head and neck. At the end of HLI therapy 10 of 30 patients were considered completely cured. In 10 patients unepithelialised skin lesions were hardly visible, in 5 the tumours were significantly reduced in size and had clear-cut borders, in 2 the tumours showed a tendency towards regression, and in 3 there was no effect. Application of HLI close to the tumour site appears to prevent dispersal of tumour cells during surgical removal of the tumour. It also inhibits metastatic spread, thereby reducing the likelihood of recurrence.

Application of human leucocyte interferon in patients with carcinoma of the uterine cervix

15 patients with invasive squamous-cell carcinoma of the uterine cervix were treated with crude human leucocyte interferon (HLI) for 3 weeks before surgical removal of the tumour. 9 patients were given HLI topically and intramuscularly and 6 topically only. In 3 patients the surgical material was free from tumour cells, in 3 it showed a lower grade of carcinoma, and in 9 the findings remained unchanged. In only 1 patient the tumour metastasised to the lymph nodes. Typically a tumour regressed to about a third of its original size. There was a sharp distinction between the tumour mass and the healthy tissue manifested in the formation of a fibrous wall. On the basis of the scores--i.e., stromal response, relation between tumour-cell and macrophage activity and reactivity, and reactivity of the original lymph nodes--the overall appraisal of the response caused by HLI therapy was as follows: in 6 patients excellent, in 5 very good, in 1 moderate, in 2 poor, and in 1 no response. It is suggested that HLI is suitable for administration both before and after surgery in patients with cervical cancer of grade I or II. If stroma cannot be induced to respond within 21 days of treatment, HLI application should be discontinued.

Application of human leucocyte interferon in patients with urinary bladder papillomatosis, breast cancer, and melanoma

Eight patients with malignant papillomaosis of the bladder, four with breast cancer, and two with malignant melanoma, all of whom had a poor prognosis, were treated with injection of crude human leucocyte interferon (HLI) into the tumour or the adjacent tissue and in some cases with intramuscular HLI injection also. All tumours showed complete or partial regression after treatment for up to 6 months. One patient with breast cancer died from distant metastases; all other patients in the trial were recurrence-free after 3--30 months of follow-up.