Increase in the Th1-Cell-Based Immune Response in Healthy Workers Exposed to Low-Dose Radiation - Immune System Status of Radiology Staff.

OBJECTIVES: Radiation is one of the most important sources of free radical (such as reactive oxygen species) production, which plays an essential role in the etiology of over hundred diseases. The aim of the study was to investigate some immune parameters and hematological indices in healthy workers of the Radiology Department, University Hospital of Mashhad, Iran. METHODS: The study was performed on 50 healthy workers: 30 radiology staff as the case group and 20 laboratory workers as the control group. The radiation dose received by the radiology staff participating in the study was less than the annual maximum permissible level, 50 millisievert. Hematological parameters, lymphocyte proliferation and cytokine production were studied in both groups. RESULTS: Among healthy radiology workers, the hematological indices did not differ statistically; however, their proliferation indices and IFN-γ levels showed significant increases in parallel with decreases in the IL-4 levels as compared to controls. The immune system of workers exposed to low-dose ionizing radiation was found to be shifted from a Type 2 to a Type 1 response to promote cellular immunity. CONCLUSION: Based on our data, exposure to low-dose ionizing radiation may decrease the prevalence, frequency, and recurrence of various cancers and infectious diseases because of an increase in Th1-cell-based response, thus leading to more protection of the human body against tumor cells and foreign agents and possibly increased longevity. However, due to high rate of fluoroscopy use for interventional radiology, we suggest continuing research projects on radiation protection and hazards to prevent irreversible damage. As a recommendation, in future studies, radiology staff with a weakened immunity due to high radiation exposure should be considered as good choices to be treated using acupuncture techniques because acupuncture has been demonstrated to enhance the function and the number of immune cells.

Safranal as a safe compound to mice immune system.

OBJECTIVES: The aim of the present study was to investigate immunotoxic effect of safranal (SAF), a main component of Crocus sativus essential oil, using Balb/c mice. MATERIALS AND METHODS: SAF was administered intraperitoneally at doses of 0.1, 0.5 and 1 ml/kg for 3 weeks. Hystopathological examination of spleen and bone marrow, cellularity of spleen, delayed type of hypersensitivity (DTH) response, hemagglutination titer (HA), cytokine production and lymphocyte proliferation assay were studied in various groups of animals. RESULTS: Spleen cellularity for SAF groups (0.1 ml/kg SAF: 6.68 [± 0.88] × 10(7), 0.5 ml/kg SAF: 8.16 [± 1.33] × 10(7), 1 ml/kg SAF: 6.12 [± 0.59] × 10(7)) did not significantly differ as compared to vehicle control (8.52 [± 1.36] × 10(7); p > 0.05). In addition, SAF at all doses could not produce any significant changes in hematological parameters, HA titer, DTH and lymphoproliferation responses, as well as in release of cytokines by isolated splenocytes (p > 0.05). Despite a few studies demonstrating some immunomodulatory effects for saffron extract, SAF as a major constituent of saffron did not induce any marked effects in immune system parameters of mice. CONCLUSION: Contrary to the toxicological studies which have indicated that SAF is more toxic than other active constituents in saffron stigma, at least it was found to be safe to mice immune system and has no toxicity on humoral and cellular immune responses.