Age Dependence of Hematopoietic Progenitor Survival and Chemokine Family Gene Induction after Gamma Irradiation in Bone Marrow Tissue in C3H/He Mice
RADIATION RESEARCH
Authors: Ariyoshi, Kentaro; Takabatake, Takashi; Shinagawa, Mayumi; Kadono, Kyoko; Daino, Kazuhiro; Imaoka, Tatsuhiko; Kakinuma, Shizuko; Nishimura, Mayumi; Shimada, Yoshiya
Abstract
Age at exposure is a critical factor that influences the risk of radiation-induced leukemia, which arises from hematopoietic stem and progenitor cells. However, little is known about the effect of age on the radiation response of these cells. In this study, we examined the radiation response of hematopoietic stem and progenitor cells in infant (1-week-old), juvenile (3-week-old), and adult (8- and 14-week-old) C3H/He mice, which are susceptible to radiation-induced myeloid leukemia. We first observed an age-dependent increase in the radioresistance of hematopoietic stem and progenitor cells after in vivo irradiation. However, in vitro irradiation of progenitor cells did not show any age differences, suggesting that radiation sensitivity in vivo is dependent on the bone marrow microenvironment rather than to intrinsic properties of progenitors themselves. Expression profiles of bone marrow tissues identified chemokine and cytokine family genes, whose expression differed between infant and adult tissues at time points before and after irradiation. Among the selected thirteen cytokines reported to be radioprotective, we observed increased expression of Csf1, Csf2, Cxcl12, Fgf1, Fgf7, Il1a, Il1b and Kitl after irradiation, mostly in adult tissues. Specifically, Csf2, Fgf1 and Il1b expression, as revealed by qPCR, were significantly enhanced in adult bone marrow tissue after irradiation, but were unresponsive to irradiation in infant tissue. These results suggest that the higher susceptibility of infant hematopoietic stem and progenitor cells to the cell killing effect of ionizing radiation may be attributed to a failure to induce a subset of radioprotective cytokines in the immature bone marrow microenvironment. (C) 2014 by Radiation Research Society
Evaluation of Chemokine mRNA Expression to Assess Allergic Inflammation of the Ocular Surface in Chronic Allergic Conjunctival Diseases
CORNEA
Authors: Aso, Hiroshi; Shoji, Jun; Shiraki, Yukiko; Inada, Noriko; Yamagami, Satoru
Abstract
Purpose: We validated the use of chemokine messenger RNA (mRNA) expression analysis for the assessment of ocular surface allergic inflammation in chronic allergic conjunctival diseases (ACDs) with proliferative lesions, including giant papillae and gelatinous infiltration of the limbus. Methods: This prospective sectional study included 19 patients with chronic ACDs and 10 healthy volunteers as controls. Patients with chronic ACDs were divided into 2 subgroups according to the severity of the clinical score: active stage ACD subgroup (n = 9) and stable stage ACD subgroup (n = 10). Impression cytology using a filter paper for each upper tarsal conjunctiva of the patients with chronic ACDs and control subjects was performed, and the expression levels of IL1A, CXCL8, IL16, and CCL24 mRNAs encoding interleukin (IL)-1 alpha, CXCL8/IL-8, IL-16, and CCL24/eotaxin-2, respectively, were determined by quantitative real-time polymerase chain reaction using impression cytology specimens. Results: CCL24 and IL16 mRNA levels in the active ACD subgroup were significantly higher than those in the control group (P = 0.003 and 0.004, respectively). IL1A and CXCL8 expression levels in the active ACD subgroup were significantly higher than those in the stable ACD (P = 0.008 and 0.029, respectively) and control (P = 0.008 and 0.014, respectively) subgroups. Furthermore, significant correlations were detected between IL16 and CCL24 mRNA levels (r = 0.76, P = 0.0001) and between IL1A and CXCL8 (r = 0.67, P = 0.0004). Conclusions: At least 2 kinds of inflammatory reactions, IL-1aand CXCL8-associated inflammation and CCL24-and IL-16-associated inflammation, may be involved in the exacerbation of chronic ACDs.