The Units of IgM, IgA and IgG Rheumatoid Factors by Enzyme Linked Immunosorbent Assay in Human Sera

The measurement of Rheumatoid Factor (RF) has been a valuable tool in diagnosing Rheumatoid Arthritis (RA) for many years. Since Waaler's discovery of the RF, many studies have been carried out. In the recent years studies have been shown that there is no such correlation between the level of the RF titers and disease activity. In this report we have measured the IgM-RF, IgA-RF and IgG-RF by an Enzyme linked immunosorbent assay (ELISA) for 144 normal human sera and 50 patients sera. At the same time we have measured the titers of gelatin particle agglutination (RAPA) and the Latex agglutination (RA-test). The value of IgG-RF have been most correlated to the titers of RAPA (r=0.9037). Using this ELISA technic to detect IgM-, IgA- and IgG-RF, have been aviable more clearly the activity and the stage of Rheumatoid disease

Lymphocyte blastogenesis in normal and low birth weight infants and the effect of monocyte depletion on it

Peer Reviewe

Parg deficiency sensitizes to radiation of low-high LET with enhanced apoptosis induction in mouse ES cells

Poly(ADP-ribose) glycohydrolase (Parg) is the main enzyme for poly(ADP-ribose) degradation. The impact of Parg and poly(ADP-ribose) polymerase-1 (Parp-1) deficiency for sensitization of low to high linear-energy-transfer (LET) radiation was studied in mouse ES cells. Parg-/- cells showed higher sensitivity to -irradiation compared to Parp-1-/- cells. Augmented H2AX levels in Parg-/- ES cells implied a delayed repair of double strand breaks. Parg-/- ES cells show increased apoptotic ladder formation after irradiation. The effect of Parg and Parp-1 deficiency on responses to heavy ion irradiation of carbon- and Fe-ions was investigated. Parg-/- and Parp-1-/- ES cells showed enhanced apoptosis 24 hrs after carbon-ion irradiation. Parg-/- cells showed sensitization after 5 Gy carbon-ion irradiation in clonogenic survival assay, whereas clear sensitization was not noticed for Parp-1-/- ES cells. Notably, sensitization was observed at higher dose than 2 Gy for both LET 13 and 70 carbon-radiation. These results suggests that Parg deficiency sensitized mouse ES cells to radiation of a wide therapeutic range of LET values with enhanced apoptotic cell death induction.第70回日本癌学会学術総

Radiosensitization Effect of PARP Inhibitor in Cells Exposed to Low and High LET Radiation

Purpose: To improve radiotherapy of cancer patients, development of efficient radiosensitizer is one of the most important issues in clinical cancer treatment. Poly (ADP-ribose) polymerase (PARP)-1 is a nuclear enzyme that promotes base excision repair and DNA strand break repair. Inhibitors of PARP have been shown to enhance the cytotoxic effects of ionizing radiation and DNA damaging agents. We investigated the impact of inhibition of PARP on responses to gamma-irradiation (low LET (liner energy transfer) radiation) and carbon-ion irradiation (high LET radiation) in human pancreatic cancer cell line MIA PaCa-2.Methods and Materials: We measured the cell survival by a colony formation assay under combination of PARP inhibitor AZD2281 (one of PARP inhibitors used in clinical trials) and single fraction of gamma-irradiation and carbon-ion irradiation (LET 13 and 70 keV/um). We also analyzed the effect on DNA damage response (DDR) by pulse field gel electrophoresis (PFGE), western blotting and flow cytometry. Results: The colony formation assay showed that addition of PARP inhibitor enhanced the effect of gamma-, LET 13 and LET 70 carbon-ion irradiation on cell survival compared to irradiation alone. Increased levels of gamma-H2AX and phosphorylated p53 (p-p53) (Ser-15) were observed after gamma-irradiation in the presence of PARP inhibitor. We also observed increased levels of gamma-H2AX both after LET 13 and 70 keV/m carbon-ion irradiation, but the increased level of p-p53 was not detected. These results suggest that PARP inhibitor enhances DDR and a local delay in DNA double strand break (DSB) processing after irradiation, whereas after in carbon-ion irradiation these occurred independenty from p53 phosphorylation status. Attenuated level of phosphorylated histone H3 was observed after gamma- and carbon-ion irradiation in the presence of AZD2281, suggesting an increase of S phase arrest. PARP inhibitor induced S phase arrest and subsequent G2/M arrest both after gamma and carbon-ion irradiation in flow cytometry, suggesting that the S phase arrest might contribute to cell death. Conclusion: PARP inhibitor AZD2281 sensitized both gamma- and carbon-ion irradiated MIA PaCa-2 cells. Enhanced and prolonged DDR by AZD2281 were observed. PARP inhibitor may be useful when combined with low or high LET radiation in cancer therapy.The 53rd Annual Meeting of the American Society For Therapeutic Radiology and Radiation Oncology (ASTRO

Radiosensitization Effect of PARP Inhibition in Cells Exposed to Low and High LET Radiation

Poly(ADP-ribose) polymerase (PARP)-1 promotes base excision repair and DNA strand break repair. Inhibitors of PARP enhance the cytotoxic effects of gamma- and X-irradiation. We investigated the impact of PARP inhibition on the responses to gamma-irradiation (low LET (liner energy transfer) radiation) and carbon-ion irradiation (high LET radiation) in the human pancreatic cancer cell line MIA PaCa-2. Cell survival was assessed by colony formation assay after combination treatment with the PARP inhibitor AZD2281 and single fraction gamma-irradiation and carbon-ion irradiation (LET 13 and 70 keV/um). The DNA damage response (DDR) was assessed by pulse field gel electrophoresis (PFGE), Western blotting and flow cytometry. Treatment with a PARP inhibitor enhanced the cytotoxic effect of gamma-, LET 13 and LET 70 carbon-ion irradiation. Moreover, the radiosensitization effect was greater for LET 70 than for LET 13 irradiation. Prolonged and increased levels of gamma-H2AX were observed both after gamma- and carbon-ion irradiation in the presence of the PARP inhibitor. Enhanced level of phosphorylated-p53 (Ser-15) was observed after gamma-irradiation but not after carbon-ion irradiation. PARP inhibitor treatment induced S phase arrest and enhanced subsequent G2/M arrest both after gamma- and carbon-ion irradiation. These results suggest that the induction of S phase arrest through an enhanced DDR and a local delay in DNA double strand break processing by PARP inhibition caused sensitization to gamma- and carbon-ion irradiation. Taken together, PARP inhibitors might be applicable to a wide therapeutic range of LET radiation through their effects on the DDR

Parg deficiency confers radio-sensitization through enhanced cell death in mouse ES cells exposed to various forms of ionizing radiation

Poly(ADP-ribose) glycohydrolase (Parg) is the main enzyme involved in poly(ADP-ribose) degradation. Here, the effects of Parg deficiency on sensitivity to low and high linear-energy-transfer (LET) radiation were investigated in mouse embryonic stem (ES) cells. Mouse Parg-/- and poly(ADP-ribose) polymerase-1 deficient (Parp-1-/-) ES cells were used and responses to low and high LET radiation were assessed by clonogenic survival and biochemical and biological analysis methods.Parg-/-cells were more sensitive to gamma-irradiation than Parp-1-/- cells. Transient accumulation of poly(ADP-ribose) was enhanced in Parg-/-cells. Augmented levels of phosphorylated H2AX (gamma-H2AX)from early phase were observed in Parg-/- ES cells. The induction level of p53 phophorylation at ser18 was similar in wild-type and Parp-1-/- cells and apoptotic cell death process was mainly observed in the both genotypes. These results suggested that the enhanced sensitivity of Parg-/- ES cells to gamma-irradiation involved defective repair of DNA double strand breaks. The effects of Parg and Parp-1 deficiency on the ES cell response to carbon-ion irradiation (LET13 and 70 keV/um) and Fe-ion irradiation (200 keV/um) were also examined. Parg-/- cells were more sensitive to LET 70 keV/um carbon-ion irradiation than Parp-1-/- cells. Enhanced apoptotic cell death also accompanied augmented levels of gamma-H2AX in a biphasic manner peaked at 1 and 24 h. The induction level of p53 phophorylation atser18 was not different between wild-type and Parg-/- cells. The augmented level of poly(ADP-ribose) accumulation was noted after carbon-ion irradiation compared to gamma-irradiation even in the wild-type cells. An enhanced poly(ADP-ribose) accumulation was further observed in Parg-/- cells. Both Parg-/- cells and Parp-1-/- cells did not show sensitization to Fe-ion irradiation. Parg deficiency sensitizes mouse ES cells to a wide therapeutic range of LET radiation through the effects on DNA double strand break repair responses and enhanced cell death