Histological characteristics of cutaneous and thyroid mast cell populations in male rats exposed to power-frequency electromagnetic fields

PURPOSE: The objective of this study was to determine whether mast cells (MC) in skin and thyroid gland, cutaneous nerve fibers and eosinophils are sensitive to the influence of electromagnetic fields (EMF). MATERIALS AND METHODS: The experiment was performed on two-month-old Wistar male rats, exposed to 50 Hz EMF (100-300 microT, 54-160 V/m) for 4 h a day, seven days a week during one month. After sacrifice, samples of skin and thyroid were processed for toluidine blue staining or indirect immunohistochemistry. The M42 grid placed in the ocular of a light microscope and a special microscopic frame placed in the ocular of a fluorescence microscope were used for stereological analysis. RESULTS: The numerical and volume density of intact type A MC in the thyroid of the exposed group was significantly higher compared to the control. A number of MC and immunoreactive nerve fibers were observed in the skin and of histamine-immunoreactive MC in the thyroid of exposed animals. The differences in stereological data were not statistically significant by the Mann-Whitney test. CONCLUSIONS: The results indicate certain alterations of cutaneous and thyroid MC in rats exposed to EMF. However, the possible outcome of changes in the MC population under EMF influence on morphophysiological properties of other structures in skin and thyroid requires further investigation.     

Determination of in vivo protein synthesis in human palatine tonsil

The palatine tonsils are constantly exposed to ingested or inhaled antigens which, in turn, lead to a permanent activation of tonsillar immune cells, even in a basic physiological state. The aim of the present study was to investigate if the immunological activation of the human palatine tonsil is reflected by a high metabolic activity, as determined by in vivo measurement of protein synthesis. The protein synthesis rate of the tonsil was also compared with that of the circulating T-lymphocytes, the total blood mononuclear cells and the whole population of blood leucocytes. Phenotypic characterization of immune-competent cells in tonsil tissue and blood was performed by flow cytometry. Pinch tonsil biopsies were taken after induction of anaesthesia in healthy adult patients (n=12) scheduled for ear surgery, uvulopalatopharyngoplasty or nose surgery. Protein synthesis was quantitatively determined during a 90-min period by a flooding-dose technique. The in vivo protein synthesis rate in the palatine tonsils was 22.8+/-5.7%/24 h (mean+/-S.D.), whereas protein synthesis in the circulating T-lymphocytes was 10.7+/-3.4%/24 h, in mononuclear cells was 10.8+/-2.8%/24 h and in leucocytes was 3.2+/-1.2%/24 h. CD3+ lymphocytes were the most abundant cell population in the tonsil. The in vivo protein synthesis rate in human tonsils was higher compared with the circulating immune cells. This high metabolic rate may reflect the permanent immunological activity present in human tonsils, although cell phenotypes and activity markers do not explain the differences.     

Expression of T cell immunoglobulin- and mucin-domain-containing molecules-1 and -3 (TIM-1 and -3) in the rat nervous and immune systems

Expression of T cell immunoglobulin- and mucin-domain-containing molecules (TIMs) can be used as T helper (Th) differentiation markers in the human and mouse. We examined the expression of TIM-1 and -3 mRNAs in rat MBP(63-88)-induced experimental autoimmune encephalomyelitis (EAE). TIM-3 expression was upregulated in the spinal cord during EAE and following antigen restimulation of the encephalitogenic TCRBV8S2+ population. Interestingly, TIM-3 expression was also detected by in situ hybridization in resident cells of the nervous system. TIM-1 was expressed in B cells but not in resident CNS cells and TIM-1 mRNA levels in spinal cord were unchanged throughout the course of EAE. These results support the notion that TIM-3 can also be used as a Th1 differentiation marker in the rat. However, expression of TIM-1 and -3 is not restricted solely to T cells and the presence of TIM-3 in resident CNS cells may indicate a role for this molecule in the interaction between the nervous and immune systems.     

Indium-111-labelled donor-lymphocyte infusion by way of hepatic artery and radio-frequency ablation against liver metastases of renal and colon carcinoma after allogeneic hematopoietic stem-cell transplantation

BACKGROUND: In patients with metastatic solid cancer, antitumor effects occur after allogeneic stem-cell transplantation (SCT). However, this treatment is not as effective in the liver as against pulmonary and lymph-node metastases. To intensify the effect of donor-lymphocyte infusions (DLI) against liver metastases, intra-arterial (IA) cell injection by way of the hepatic artery (HA) can be used. METHODS: To trace infused cells, three patients with colorectal, three with renal, and one with breast carcinoma were treated with Indium-111 (111-In)-oxinate-labeled lymphocytes. Four patients received the DLI IA, all after radio-frequency ablation (RFA) of liver metastases. Three patients with other metastases received 111-In DLI intravenously (IV). One of them had RFA before SCT. RESULTS: Localization of the IA 111-In DLI activity on scintigrams homed to the liver. After IA injection, the liver to sternum ratio of radioactivity was higher compared with IV injection. Cells (CD3+, 19+, and 56+) of donor origin in biopsies of liver metastasis in two patients treated with IA injection increased to 80% to 100%. Two of four patients treated using the IA DLI showed stable size and number of liver metastases for 5 and 21 months, respectively. Both are alive 18 and 34 months after SCT. Two of three patients receiving DLI IV are doing well, with a stable metastatic disease or still without metastases 21 and 20 months after cell infusions (26 and 34 months after SCT), respectively. Three patients died because of progressive disease. CONCLUSION: When infused by way of the HA, 111-In-labeled lymphocytes home to the liver and its metastases. The liver metastasis infiltrating cells of donor origin increased. DLI by way of the HA combined with RFA may be used to treat liver metastases after SCT.