Kamiya H

Herpes Simplex Virus Type 1 Induces Apoptosis in Peripheral Blood T Lymphocytes

Apoptosis in peripheral blood T lymphocytes induced by herpes simplex virus type 1 (HSV-1) was investigated by use of DNA content analysis and the terminal deoxytransferase-mediated dUTP nick end-labeling method. The hypodiploid fraction in the cell cycle and DNA fragmentation were both increased in HSV-1-infected T lymphocytes compared with that in mock-infected T lymphocytes on stimulation with phytohemagglutinin (PHA). There was no difference in the hypodiploid fraction and DNA fragmentation between HSV-1-infected T lymphocytes and mock-infected cells cultured without PHA. HSV-1 enhanced apoptosis in CD4 and HLA-DR-positive T lymphocytes, but not in CD8 lymphocytes, when stimulated with PHA. These results demonstrate that HSV-1 infection enhances apoptosis in activated T lymphocytes, particularly CD4 and HLA-DR-positive T lymphocytes. bcl-2 expression was unchanged in mock- and HSV-1-infected CD4 and CD8 lymphocytes cultured with or without PHA, indicating that bcl-2 does not contribute to HSV-1-induced apoptotic cell death. Apoptosis in CD4 helper T lymphocytes may account for immunosuppression and lymphocytopenia following HSV-1 infection.

Development of Varicella Vaccine

The Oka strain of varicella-zoster virus (VZV) was first isolated from vesicles of an otherwise healthy 3-year-old boy with typical varicella. The virus was passaged 11 times in human embryonic lung fibroblasts at 34 degrees C and 12 times in guinea pig embryo fibroblasts (GPEFs) at 37 degrees C. GPEFs were the only nonprimate cells tested in which some degree of viral replication occurred. The resultant virus was temperature sensitive and showed host dependency, measured as better replication in GPEFs than that shown by the parental virus. The passaged virus was used as a candidate varicella vaccine and proved safe and effective for healthy and immunocompromised children. During the follow-up of vaccinated children with acute lymphocytic leukemia, the incidence of herpes zoster (HZ) was significantly lower among children who did not have a rash after vaccination, compared with those who had a rash caused by VZV (6 [2.3%] of 260 vs. 12 [17.1%] of 70, respectively). Because of the pathogenesis of VZV, the incidence of latency and of HZ is predicted to be lower among vaccine recipients than among individuals who have experienced varicella.

Two Outbreaks of Yersinia pseudotuberculosis 5a Infection in Japan

In the summer of 1984 there occurred 2 outbreaks of infection with Yersinia pseudotuberculosis 5a. 58 persons ate meat products, vegetables and rice at a Japanese barbecue restaurant. 39/58 (67%) developed symptoms. In 19/39 persons an infection with Y. pseudotuberculosis could be diagnosed by stool cultures and/or serological techniques. Fever occurred in all patients, exanthema in 68% and abdominal pain in 68%. Thus, human yersiniosis due to Y. pseudotuberculosis 5a could be a febrile disease with exanthema and gastrointestinal disturbances. A transient acute renal failure developed around the 10th day of illness in 4 children. The source and mode of spread of this infection could not be clarified.

A Live Varicella Vaccine

A live varicella vaccine has been developed, and its safety and immunogenicity have been established in normal children as well as in high-risk children.

Sequence-dependent antitumor effect of VP-16 and 1-β-d-arabinofuranosylcytosine in L1210 ascites tumor

The sequence-dependence of the antitumor effect of etoposide (VP-16) and 1-beta-D-arabinofuranosylcytosine (ara-C) was investigated against the L1210 ascites tumor in BDF1 mice. Treatment with VP16 (7.5 or 15 mg/kg) and ara-C (25 or 500 mg/kg) was administered intraperitoneally on days 1, 4 and 7 after tumor inoculation. Six hour pretreatment with 15 mg/kg VP16 followed by 500 mg/kg ara-C yielded a 100% cure rate, but only a 20% cure rate was obtained with the reverse sequence. Simultaneous administration of 15 mg/kg of VP-16 and 500 mg/kg ara-C interacted synergistically, producing a 70% cure rate. In contrast with the results obtained with VP-16 and 500 mg/kg ara-C, simultaneous administration of 25 mg/kg ara-C neither antagonized nor potentiated the antitumor effect of VP-16. Twenty-five mg/kg ara-C was too low to produce any antitumor effect with VP-16 in simultaneous administration. At every dose investigated, pretreatment with VP-16 followed by ara-C was the most effective antitumor schedule in L1210 leukemia. This sequence of drug administration did not cause greater toxicity as measured by weight loss or toxic death.

Five‐year survivors among children with acute leukemia in Japan

This Japanese nation‐wide survey was carried out on long‐term survivors among children with leukemia, i.e. those who had survived more than 5 years by October of 1974. Eighty‐three children were surveyed. This was about 2.5 times as many as the 31 children surveyed in the first Japanese nation‐wide survey in 1971. Clinical and laboratory data were also analyzed statistically and compared to that of the first survey. Most of the children had received inductive therapy according to the old protocol, but 10 children were treated with a combination of VCR and steroids. Nine of these 10 were still in a state of remission. CNS involvement occurred in 15. 3% of the cases and a late onset of this complication implied a prognostic significance: among the 9 children whose complication had occurred 3. 5 years after onset of the disease, 6 died. The relapse rate decreased between the 4th and 5th year after initiation of maintenance therapy. The percentage of the risk of death became zero after the 9th year. Cancer 40:349–357, 1977.

Discontinuing therapy in childhood acute lymphoblastic leukemia treated with a chemoimmunotherapy protocol.

SummaryWe examined the results of discontinuing therapy in Japanese children with acute lymphoblastic leukemia. Of the 209 patients in the chemoimmunotherapy study, 120 (57.4%) had all chemotherapy stopped after 3 years of complete remission, and 72 (34.4%) reached the point of discontinuing immunotherapy after 5 years of complete remission. Of the 120 children removed from chemotherapy, 14 (11.7%) have relapsed, mainly in the extramedullary sites (5: testis, 5: bone marrow, 3: central nervous system, 1: bone); relapses occurred 1–23 months after cessation of chemotherapy (median 11 months). Boys had higher post-chemotherapy relapse rate than girls (0.21 versus 0.08, P<0.05). None of the 72 children removed from immunotherapy have yet relapsed. Long-term remission and possibly cure can be expected in approximately one-half of newly diagnosed Japanese patients. Although the active immunotherapy had no beneficial effect on the overall outcome for leukemic children, it could be of benefit to the elimination of bone marrow relapses after cessation of chemotherapy.

A flow cytometric method for measurement of hydrogen peroxide generation by pediatric polymorphonuclear leukocytes stimulated by Staphylococcus aureus and Escherichia coli

The generation of hydrogen peroxide (H2O2), one of the reactive oxygen species, by polymorphonuclear leukocytes (PMN) stimulated by Staphylococcus aureus and Escherichia coli was studied in infants by cytofluorography. After heparhized whole blood was incubated with bacteria for 60 min, generated H2O2 was measured. The positive rate of H2O2 generation of PMN and mean fluorescent intensity of positive PMN stimulated by S. aureus and E. coli were significantly reduced in infants aged < 1 year and H2O2 generation increased with advancing age. In 10–15 year old children, the level of generated H2O2 reached adult levels. When sera from 1 year old children were added to separated PMN from healthy adults, H2O2 generation was reduced. In contrast, H2O2 generation by PMN from 1 year old children was increased by the addition of adult sera.

Incorporation ofN 4-behenoyl-1-β-d-arabinofuranosylcytosine into DNA as 1-β-d-arabinofuranosylcytosine

BHAC is a newly synthesized lipophilic derivative of ara-C. To clarify its pharmacological mode of action, P388 murine leukemic cells were incubated with two different types of14C-labeled BHAC, [cytosine-2-14C]BHAC and [acyl-1-14C]BHAC, and DNA was extracted with phenol. The phenol-extracted DNA was then hydrolyzed by nuclease P1 and analyzed with high-performance liquid chromatography (HPLC). The radioactivity of DNA, from the cells incubated with [cytosine-2-14C]BHAC, was detected as ara-CMP. But the radioactivity of DNA, from the cells incubated with [acyl-1-14C]BHAC, was hardly detected. On the other hand, the main radioactivity of the acid soluble fraction was determined as ara-CTP. On the basis of our results, BHAC is not phosphorylated directly to produce N4-behenoly-ara-CTP, but is mainly converted to ara-C which subsequently produces ara-CTP, the active metabolite of the drug, and which is then incorporated into DNA.

Cross-resistance to ouabain in a murine leukemia cell variant selected for cis-dichlorodiammineplatinum(II) resistance

A murine leukemic cell line (R1.1) variant (R1.1/CDDPR-E8) resistant to cis-dichlorodiammineplatinum(II)(CDDP) was also found to be resistant to ouabain, a postulated specific inhibitor of sodium-potassium ATPase. The variant established by the culture of parental cells in step by step increasing concentrations of CDDP, exhibited 11-fold higher resistance to CDDP than the parental R1.1 cells. The present study suggests that a mutational change leading to an alteration in cell membrane characteristics associated with ouabain has also changed the sensitivity of cells against CDDP. Alternatively, the present data may indicate that the cytotoxicity of CDDP is closely linked to its effects on cell membrane.