OBJECTIVE: To investigate the effects of low-dose irradiated autologous peripheral blood reinfusion (LDIAPBR) on a rat model of radiation-induced leukopenia. METHODS: The rats were randomly divided into four groups. In the LDIAPBR group, LDIAPBR was performed 1 day before modeling (10% of the total circulating blood volume was withdrawn, irradiated with 100 mGy ex vivo, and completely reinfused). Meanwhile, the normal group and model group only underwent blood withdrawal and reinfusion of the same proportion without blood irradiation. Except for the normal group, all groups were subjected to 1 Gy X-ray whole-body irradiation to establish a radiation-induced leukopenia rat model. The positive drug group received subcutaneous injection of rhG-CSF after modeling. It was monitored that the general condition of the rats, peripheral blood cell counts, immune organ indices, bone marrow nucleated cell counts and viability, and the pathological analysis of bone marrow sections was conducted. RESULTS: The LDIAPBR group exhibited significant improvements in overall condition compared to the model group. Notably, compared with the model group, peripheral blood leukocyte and lymphocyte counts were markedly higher in the LDIAPBR group. Furthermore, there was a significant increase in both the number and viability of nucleated cells in the bone marrow. Pathological examination of bone marrow sections revealed increased nucleated cell density and reduced cavity area in the LDIAPBR group. CONCLUSION LDIAPBR can effectively improve hematological parameters and bone marrow hematopoietic function in a rat model of radiation-induced leukopenia, providing a new approach for the prevention and treatment of radiation-related injuries.
Animals ; Leukopenia/prevention & control* ; Rats ; Blood Transfusion, Autologous ; Whole-Body Irradiation ; Radiation Injuries, Experimental/therapy*

OBJECTIVE: To investigate the effect of irradiation dose rate of ⁶⁰Co γ-ray on hematopoietic and immune cells in total body irradiation (TBI) mice. METHODS: After TBI with 8 Gy ⁶⁰Co γ-ray at three irradiation dose rates of 0.027, 0.256 and 0.597 Gy/min, the survival and change of body weight of C57BL/6J mice were observed within 30 days. The peripheral blood parameters were examined at each time point within 30 days post-irradiation. The hematopoietic stem/progenitor cell counts of mice were examined on the 10^th and 30^th day post-irradiation by flow cytometry, as well as the proportions of immune cells in peripheral blood, bone marrow and spleen of mice on the 30^th day post-irradiation. RESULTS: After TBI with 8 Gy ⁶⁰Co γ-ray, the 30-day survival rate of high dose-rate group was 0, which was significantly lower than 90% of medium dose-rate group and 100% of low dose-rate group (both P < 0.001). The peripheral blood parameters of all three groups showed a sharp decline → low value → gradually recovering trend. The count of white blood cell, neutrophil, lymphocyte, red blood cell, platelet and hemoglobin level in the high dose-rate and medium dose-rate groups were significantly lower than those in the low dose-rate group on day 7-18 post-irradiation (all P < 0.05), but there were no significant differences between the high dose-rate and medium dose-rate groups (P >0.05). On the 10^th day after irradiation, the proportion and number of bone marrow hematopoietic stem/progenitor cells (including LK, LSK, LT-HSC, ST-HSC, and MPP cells) in the low dose-rate and medium dose-rate groups were significantly decreased compared to those in the normal group (all P < 0.05), but there were no significant differences between the two groups (P >0.05). On the 30^th day after irradiation, LSK, LT-HSC, ST-HSC and MPP cells in the low dose-rate group recovered to normal levels, while those in the medium dose-rate group were still significantly lower than those in the low dose-rate group (all P < 0.001). The results of bone marrow and peripheral immune cell tests on the 30^th day after irradiation showed that the ratios of T and B lymphocytes in the low dose-rate and medium dose-rate groups were reduced compared to that in the normal group (both P < 0.05), while the ratio of neutrophils was increased (P < 0.01). The trend of changes in the spleen and peripheral blood was consistent. CONCLUSION The degree of hematopoietic and immune cell damage in mice after TBI with 8 Gy ⁶⁰Co γ-ray is related to the dose rate, and low dose-rate irradiation can reduce the damage in the animal model. Therefore, choosing the appropriate dose rate of irradiation is a key factor in establishing an objective and reliable experimental animal model of irradiation.
Animals ; Mice ; Whole-Body Irradiation ; Gamma Rays ; Mice, Inbred C57BL ; Hematopoietic Stem Cells/radiation effects* ; Cobalt Radioisotopes ; Dose-Response Relationship, Radiation ; Male

OBJECTIVE: To explore the chronic injury and its possible mechanism of ionizing radiation on multipotent hematopoietic progenitor cells (MPPs) by determining the related indicators of MPPs in bone marrow of mice post-radiation. METHODS: Sixteen C57BL/6 adult mice were randomly divided into normal control and irradiation groups, 8 mice in each group. The mice in irradiation group were exposed to 6 Gy X-ray. The proportion of bone marrow MPPs, their apoptosis and proliferation 2 months after irradiation were detected by flow cytometry. Mitochondrial activity and levels of reactive oxygen species (ROS) in each MPPs population were detected by Mitotracker Red and DCFDA probes, and the senescent state of MPPs in the bone marrow was analyzed. RESULTS: Ionizing radiation could reduce the proportion of MPPs in mouse bone marrow. The proportions and numbers of MPP1, MPP3 and MPP4 in the bone marrow were significantly decreased after whole-body irradiation with 6 Gy X-ray (P<0.05). In addition, radiation significantly reduced the colony-forming capacity of MPPs in bone marrow (P<0.05), the proportions of apoptotic cells in the MPP1 and MPP4 cell populations increased significantly in the bone marrow (P<0.05). The activity of mitochondria was significantly reduced in the bone marrow MPP2, MPP3 and MPP4 cell populations compared with that of the control group (P<0.05). It was also found that the radiation could significantly increase the ROS levels of MPPs in bone marrow, and the content of ROS in the MPP2, MPP3 and MPP4 cell population of the bone marrow was significantly increased(P<0.05). The senescent cells ratios of MPP1, MPP3 and MPP4 cells in the bone marrow after irradiation were significantly higher than those in the control group (P<0.05). CONCLUSION Ionizing radiation can cause chronic MPPs damage in mice, which is closely associated with persistent oxidative stress, cells apoptosis, and cellular senescence.
Mice ; Animals ; Bone Marrow ; Reactive Oxygen Species ; Mice, Inbred C57BL ; Hematopoietic Stem Cells ; Whole-Body Irradiation ; Radiation, Ionizing ; Bone Marrow Cells

OBJECTIVE: To investigate the effect of acute graft-versus-host disease (aGVHD) mouse models established respectively by total body irradiation (TBI) and busulfan combined with cyclophosphamide (BU/CY) conditioning regimens after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: Bone marrow cells and splenic mononuclear cells were isolated respectively from femur, tibia, and spleen of C57BL/6 male mice (H-2Kb) which were selected as donors. After TBI pretreatment, BALB/c female mice (H-2Kd) were injected with donor bone marrow cells 1×10⁷/50 μl and splenic mononuclear cells 2×10⁷/100 μl through caudal vein, while CB6F1 female mice (H-2Kd/b) with donor bone marrow cells 2×10⁷/100 μl and splenic mononuclear cells 1×10⁸/500 μl after BU/CY pretreatment. The successful establishment of the aGVHD models were determined by post-transplant manifestations, rate of chimerism, target organ damage, etc. Results: After transplantation, mice of both groups showed listlessness, low activity, continued weight loss, and typical manifestations of aGVHD such as alopecia, hunched posture, diarrhea, and anal swelling. and died within 4 weeks. Flow cytometry detection showed complete chimerism in all the mice. Pathological examination of skin, intestines, liver, lung, and spleen tissues showed obvious aGVHD pathological changes. However, the weight loss, ruffled fur, and alopecia combined with severe scurf on those hair-free areas were significantly apparent in TBI group than BU/CY group, as well as higher aGVHD score, and the differences were statistically significant (P<0.05). CONCLUSION Both TBI and BU/CY as conditioning regimens can successfully establish stable mouse models of aGVHD after fully allo-HSCT and haploidentical HSCT for further research about mechanism of aGVHD. BU/CY conditioning regimen can more truly simulate physiological status in vivo of patients with chemotherapy based conditioning regimen, while TBI conditioning regimen shows significantly more typical aGVHD symptoms and easier to operate.
Alopecia/drug therapy* ; Animals ; Busulfan/therapeutic use* ; Cyclophosphamide ; Female ; Graft vs Host Disease/drug therapy* ; Hematopoietic Stem Cell Transplantation ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Transplantation Conditioning ; Transplantation, Homologous ; Weight Loss ; Whole-Body Irradiation

OBJECTIVE: To study the effect of interleukin-6 (IL-6) gene deletion on radiation-induced hematopoietic injury in mice and relative mechanism. METHODS: Before and after whole body ⁶⁰Co γ-ray irradiation, it was analyzed and compared that the difference of peripheral hemogram, bone marrow hematopoietic stem and progenitor cells conts in IL-6 gene knockout (IL-6^-/-) and wild-type (IL-6^+/+) mice and serum IL-6 and G-CSF expression levels in above- mentioned mouse were detected. Moreover, 30 days survival rate of IL-6^-/- and IL-6^+/+ mice after 8.0 Gy γ-ray irradiation were analyzed. RESULTS: IL-6 levels in serum of IL-6^+/+ and IL-6^-/- mice were respectively (98.95±3.85) pg/ml and (18.36±5.61) pg/ml, which showed a significant statistical differences (P<0.001). There were no significant differences of peripheral blood cell counts and G-CSF level in serum between IL-6^+/+ and IL-6^-/- mice before irradiation (P>0.05). However, the number of leukocytes, neutrophils, lymphocytes, monocytes, platelets in peripheral blood and G-CSF level in serum of IL-6^-/- mice were significantly decreased at 6 h after 8.0 Gy γ-ray irradiation compared with that of IL-6^+/+ mice. On days 30 after 8.0 Gy γ-ray irradiation, the survival rate of IL-6^+/+ and IL-6^-/- mice was 62.5% and 12.5%, and the mean survival time of dead mice was 16.0±1.0 and 10.6±5.3 days, respectively. On days 14 after 6.5 Gy γ-ray irradiation, bone marrow nucleated cells in IL-6^+/+ and IL-6^-/- mice were respectively (10.0±1.2)×10⁶ and (8.3±2.2)×10⁶ per femur. Compared with IL-6^+/+ mice, the proportion of Lin^-Sca-1^-c-kit⁺ (LK) in bone marrow of IL-6^-/- mice had no significant change (P>0.05), but the proportion of Lin^-Sca-1⁺c-kit⁺ (LSK) was significantly decreased (P<0.05). CONCLUSION IL-6 plays an obvious role in regulating hematopoietic radiation injury, and IL-6 deficiency can inhibit the radiation-induced increase of endogenous G-CSF level in serum, aggravates the damage of mouse hematopoietic stem cells（HSC） and the reduction of mature blood cells in peripheral blood caused by ionizing irradiation, resulting in the shortening of the survival time and significant decrease of the survival rate of mice exposed to lethal dose radiation.
Animals ; Gene Deletion ; Granulocyte Colony-Stimulating Factor/pharmacology* ; Interleukin-6/metabolism* ; Mice ; Radiation Injuries ; Whole-Body Irradiation

OBJECTIVE: To observe the therapeutic effect of tetramethylpyrazine on immune-mediated bone marrow failure (BMF) induced by different doses of X-ray exposure in C57 mice. METHODS: C57BL6 mice were randomized into 4 groups, including a blank control group and 3 X-ray exposure groups with X-ray exposure at low (5.0 Gy), moderate (5.75 Gy), and high (6.5 Gy) doses. After total body irradiation with 0.98 Gy/min X-ray. The mice as recipient received injections of 4×10 lymphocytes from DBA/2 mice via the tail vein within 4 h. The survival rate of the recipient mice, peripheral blood cell counts, bone marrow nucleated cell count, and bone marrow pathology were examined at 14 days after the exposure. In the subsequent experiment, C57 mice were exposed to 5.0 Gy X-ray and treated with intraperitoneal injection of tetramethylpyrazine at the low (5 mg/mL), moderate (10 mg/mL), or high (20 mg/mL) doses (12 mice in each group) for 14 consecutive days, and the changes in BMF were observed. RESULTS: X-ray exposure, especially at the high dose, resulted in significantly lowered survival rate in the mouse models of BMF at 14 days. As the X-ray dose increased, the mice showed significantly reduced peripheral blood counts of red blood cells, white blood cells, platelets and lowered bone marrow nucleated cell counts with obvious bone marrow congestion and reduction of nucleated cells ( < 0.05 or 0.001). In the mice exposed to 5.0 Gy X-ray, tetramethylpyrazine at the high dose most obviously increased bone marrow nucleated cells ( < 0.01) and red blood cells ( < 0.001), and even at the low dose, tetramethylpyrazine significantly increased the counts of white blood cells ( < 0.05) and platelets ( < 0.01) following the exposure. Tetramethylpyrazine dose-dependently alleviated bone marrow hyperemia, increased bone marrow nucleated cell counts, and lowered Fas protein expression in the bone marrow. CONCLUSIONS X-ray irradiation at 5.0 Gy is suitable for establish mouse models of immune-mediated BMF. Tetramethylpyrazine promotes bone marrow repair by regulating Fas cell apoptosis signals, which further expands the traditional Chinese medicine theory of "removing blood stasis to create new."
Animals ; Bone Marrow ; Mice ; Mice, Inbred C57BL ; Mice, Inbred DBA ; Pyrazines ; Whole-Body Irradiation

The survival rates of boys and men with cancer have increased due to advances in cancer treatments; however, maintenance of quality of life, including fertility preservation, remains a major issue. Fertile male patients who receive radiation and/or chemotherapy face temporary, long-term, or permanent gonadal damage, particularly with exposure to alkylating agents and whole-body irradiation, which sometimes induce critical germ cell damage. These cytotoxic treatments have a significant impact on a patient's ability to have their own biological offspring, which is of particular concern to cancer patients of reproductive age. Therefore, various strategies are needed in order to preserve male fertility. Sperm cryopreservation is an effective method for preserving spermatozoa. Advances have also been achieved in pre-pubertal germ cell storage and research to generate differentiated male germ cells from various types of stem cells, including embryonic stem cells, induced pluripotent stem cells, and spermatogonial stem cells. These approaches offer hope to many patients in whom germ cell loss is associated with sterility, but are still experimental and preliminary. This review examines the current understanding of the effects of chemotherapy and radiation on male fertility.
Alkylating Agents ; Cryopreservation ; Drug Therapy ; Embryonic Stem Cells ; Fertility ; Fertility Preservation ; Germ Cells ; Gonads ; Hope ; Humans ; Induced Pluripotent Stem Cells ; Infertility ; Infertility, Male ; Male ; Methods ; Quality of Life ; Radiotherapy ; Spermatogenesis ; Spermatozoa ; Stem Cells ; Survival Rate ; Whole-Body Irradiation

BACKGROUND: Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) is a subset of ALL with poor prognosis. Here, we analyzed the outcomes and prognostic factors of children with Ph+ ALL who received imatinib and chemotherapy followed by allogeneic hematopoietic cell transplantation (HCT) in first complete remission (CR). METHODS: Thirty-one Ph+ ALL patients (female 10) diagnosed from January 2005 to December 2016 were included in the study. All patients were treated with imatinib and chemotherapy before HCT. Bone marrow (BM) evaluations included real-time quantitative polymerase chain reaction (RQ-PCR) study of the BCR-ABL1 fusion transcript. All patients received HCT with total body irradiation (TBI)-based conditioning at a median of 6.4 (range, 4.2–47.1) months from diagnosis. RESULTS: Compared to values at diagnosis, the median decrement of RQ-PCR value post-consolidation, and prior to HCT was −3.7 Log and −4.8 Log, respectively. The 5-year event-free survival (EFS) and overall survival of the patients were 64.5±9.4% (20/31) and 75.0±8.3% (23/31) respectively. Events included relapse (N=5) and death in CR post-HCT (N=6). The 5-year incidence of molecular relapse was 30.9±9.1% (9/31). An RQ-PCR decrement of at least −4 Log post-consolidation significantly predicted lower incidence of molecular relapse: 7.7±7.7% for ≥−4 Log decrement, 50.0±13.8% for <−4 Log decrement (P=0.027). CONCLUSION: Decrement in RQ-PCR for the BCR-ABL1 transcript that was determined after consolidation was the only significant prognostic factor for incidence of molecular relapse. In the post-induction TKI initiation setting, steadfast imatinib treatment during consolidation may allow for optimum post-HCT outcomes.
Bone Marrow ; Cell Transplantation ; Child ; Diagnosis ; Disease-Free Survival ; Drug Therapy ; Humans ; Imatinib Mesylate ; Incidence ; Philadelphia Chromosome ; Polymerase Chain Reaction ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Prognosis ; Recurrence ; Transplants ; Whole-Body Irradiation

There is still a need for better protection against or mitigation of the effects of ionizing radiation following conventional radiotherapy or accidental exposure. The objective of our current study was to investigate the possible roles of matrix metalloproteinase inhibitor, ilomastat, in the protection of mice from total body radiation (TBI), and the underlying protective mechanisms. Ilomastat treatment increased the survival of mice after TBI. Ilomastat pretreatment promoted recovery of hematological and immunological cells in mice after 6 Gy γ-ray TBI. Our findings suggest the potential of ilomastat to protect against or mitigate the effects of radiation.
Acute Radiation Syndrome ; blood ; immunology ; prevention & control ; Animals ; Blood Cells ; drug effects ; radiation effects ; Dose-Response Relationship, Drug ; Gamma Rays ; adverse effects ; Hydroxamic Acids ; therapeutic use ; Indoles ; therapeutic use ; Matrix Metalloproteinase Inhibitors ; therapeutic use ; Mice ; Radiation Injuries, Experimental ; blood ; immunology ; prevention & control ; Radiation-Protective Agents ; therapeutic use ; Spleen ; drug effects ; immunology ; radiation effects ; Survival Analysis ; Whole-Body Irradiation

Objective: To explore the levels of IL-22 in thymus damaged by γ-ray total body irradiation (TBI), and to study the role of IL-22 in T cell reconstitution after thymic injury induced by TBI. Methods: To induce thymic injury, mice were treated by sub-lethal TBI. Levels of intra-thymic and circulatory IL-22 were detected by using ELISA assay. Untreated mice were used as control. After receiving sub-lethal TBI, mice were intraperitoneally injected with PBS or recombinant mouse IL-22, which were marked as TBI+PBS or TBI+IL-22, respectively. Mice were monitored for counts of total thymic cells and circulatory white blood cells. Flow cytometry was applied to analyze percentages of thymic epithelial cells (TEC), thymocyte subsets and circulatory T cells. Real-time PCR assay was applied to analyze the mRNA expression levels of Foxn1, Ccl25, Aire and Dll4 in thymus. Results: ①Sub-lethal TBI treated mice expressed higher levels of intra-thymic and circulatory IL-22, compared with untreated ones (all P<0.05). ②After injection of recombinant IL-22, TBI+IL-22 mice had higher levels of intra-thymic IL-22 than TBI+PBS mice (all P<0.05). ③On day 14 after irradiation, real-time PCR assay showed that TBI+IL-22 mice had higher mRNA levels of Foxn1, Ccl25, Aire and Dll4 in thymus compared with TBI+PBS ones. Meanwhile, the TBI+IL-22 mice had higher counts of total thymic cells[(5.93±3.19)×10(6)/ml vs (1.42±0.46)×10(6)/ml, t=3.128, P=0.033] and circulatory white blood cells[(3.08±0.94)×10(6)/ml vs (1.43±0.30)×10(6)/ml, t=3.730, P=0.015] than those of TBI+PBS mice. Flow cytometry analysis indicated that TBI+IL-22 mice had higher counts of TEC and thymocytes than TBI+PBS mice on day 14 after irradiation (all P<0.05). On days 7 and 14 after irradiation, TBI+IL-22 mice had higher counts of circulatory white blood cells and T cells than TBI+PBS mice (all P<0.05). Conclusion: Sub-lethal TBI induces upregulation of intra-thymic IL-22, and injecting of recombinant IL-22 increases level of IL-22 in thymus. Injecting of recombinant IL-22 improves recovery of TEC and increases numbers of thymocyte subsets and circulatory T cell after thymic injury.
Animals ; Interleukins ; Mice ; Radiation, Ionizing ; T-Lymphocytes ; Thymus Gland ; Whole-Body Irradiation ; Interleukin-22