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M Fukasawa

Publications and source records attributed to M Fukasawa.

At least 163 records · Page 9Linked to original sources
PubMed1988

Isolation and characterization of HIV-2 from an AIDS patient in Ghana.

This report describes the isolation and characterization of a retrovirus of the HIV-2 group from a Ghanaian AIDS patient which has different restriction patterns from previously reported HIV-2 viruses. The virus was morphologically very similar to HIV-1 and HIV-2, and had Mg2+-dependent reverse transcriptase. Like previous HIV isolates, it induced severe cytopathic effects in CD4-positive human lymphoid cell lines. Its major proteins were shown to be gp110, p66, p55, p41, gp32, p30 and p26 by Western blot analysis. In dot-blot hybridization experiments, the virus hybridized with a HIV-2 DNA probe, but not with HIV-1 and SIVagm probes in stringent conditions. These data indicate that this Ghanaian virus is a HIV-2 group virus. However, in a Southern blot hybridization experiment, the restriction patterns of this virus, designated HIV-2 [GH-1], were quite different from those of previously reported HIV-2 viruses from West Africa isolated at the Pasteur Institute.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Isolation and characterization of simian immunodeficiency virus from mandrills in Africa and its relationship to other human and simian immunodeficiency viruses.

Two isolates of simian retrovirus related to the human immunodeficiency virus (HIV) were obtained from apparently healthy mandrills, Papio (Mandrillus) sphinx, in western equatorial Africa. This virus, designated SIVMND (simian immunodeficiency virus from mandrills), appeared morphologically similar to HIV by electron microscopy, showed Mg2+-dependent reverse transcriptase activity, and induced cytopathic effect in human CD4-positive cells. Western blotting (immunoblotting) analyses revealed that the gag and pol products of SIVMND showed cross-reactivity with those of known HIVs and SIVs. Molecular clones covering full-length viral DNA were obtained from closed circular extrachromosomal DNA of SIVMND-infected cells. By clone-on-clone hybridization with known retroviruses of the HIV and SIV groups, SIVMND showed similar cross-hybridization with HIV-1, HIV-2, SIVAGM (African green monkey-derived SIV), and SIVMAC (rhesus macaque-derived SIV) in the gag and pol regions only at low stringency but not at high stringency, a result indicating that SIVMND is a new member of the HIV-SIV group. The existence of distinct SIVs in different monkey species suggest that recent interspecies transfer of HIV-SIV is unlikely in nature.

Animals↗
PubMed1987

Structural abnormality and over-expression of the myc gene in feline leukemias.

Tumor cells of feline leukemia were examined for structural abnormality and expression of the myc gene. Four of 12 spontaneous leukemia cases showed structural abnormalities of the myc gene detected by Southern blotting analysis. Of these 4 cases, one (Case 1) showed a DNA rearrangement in the 5' portion of the c-myc locus associated with integration of feline leukemia virus (FeLV) genome. Another case had a newly inserted myc gene which was transduced by FeLV. In the 2 other cases, no relation of abnormalities of the myc gene to FeLV was detected. One case of experimental leukemia induced by inoculation of a cell line, FT-1, established from Case 1 showed a c-myc gene rearrangement similar to that observed in Case 1. Expression of myc RNA was examined in 3 leukemia T-cell lines, FT-1, FL74 and F422, by Northern blotting analysis. A high level of myc transcript was detected in all 3 cell lines. The size of myc RNAs in FT-1 and FL74 was the same as that of normal myc RNA, while in F422 which had myc-containing FeLV (myc-FelV), the full genome and spliced form of myc-FeLV viral RNA were detected.

Animals↗
PubMed1987

Serological survey and virus isolation of simian T-cell leukemia/T-lymphotropic virus type I (STLV-I) in non-human primates in their native countries.

Infection with a simian retrovirus (STLV-I) closely related to human T-lymphotropic virus type I (HTLV-I) was investigated in non-human primates living in their native countries in Africa and Asia. Serum antibodies cross-reacting with HTLV-I antigens were detected in 85 of 567 non-human primates of 30 species. Seropositive animals were found among African green monkeys, olive baboons, Sykes' monkeys, mandrills and patas monkeys in several countries in Africa, and cynomolgus monkeys, Celebes macaques and siamangs in Indonesia. The frequency of seropositivity was much higher in adult than in young African green monkeys, cynomolgus monkeys and Celebes macaques. STLV-Is were isolated by establishing II lines of virus-producing lymphoid cells in the presence of interleukin-2 from 5 species of seropositive non-human primates, i.e. the African green monkey, Sykes' monkey, Celebes macaque, cynomolgus monkey and siamang. All these cell lines had T-cell markers and Tac antigen, and the cell lines from the African green monkey and Sykes' monkeys were Leu2a+ while those from other species were Leu3a+. These cell lines expressed viral antigens reacting with human sera from adult T-cell leukemia (ATL) patients and monoclonal antibodies (MAbs) against p19 and p24 of HTLV-I core proteins, and produced virus particles having RNA-dependent DNA polymerase activity. Cellular DNAs from these cell lines contained provirus sequences homologous to HTLV-I, shown by Southern blot hybridization. The restriction patterns of these provirus genomes were different from those of HTLV-I and were also dissimilar in the different species.

Age Factors↗
PubMed1987

Development of adult T-cell leukemia-like disease in African green monkey associated with clonal integration of simian T-cell leukemia virus type I.

Proviral integration of a simian retrovirus highly homologous to human T-cell leukemia virus type I was examined in cellular DNAs extracted from primary peripheral blood lymphocytes of 31 adult African green monkeys (Cercopithecus aethiops) that were seropositive for simian T-cell leukemia virus type I (STLV-I). Among these monkeys, one case with overt leukemia, showing pleomorphic leukemia cells similar to those in human adult T-cell leukemia (ATL), and five cases in a preleukemic state of ATL-like disease were found. Judging from the integration site of the provirus genome, primary lymphocytes of these leukemic or preleukemic cases contained monoclonally proliferated STLV-I-infected cells, whereas lymphocytes of other seropositive monkeys without hematological abnormalities were polyclonal, and those of seronegative monkeys did not contain the provirus. The restriction patterns with PstI ans SstI of most STLV-I proviruses were identical to those of the previous isolate from this species, but in three monkeys there was a deletion of one PstI site. From the correlation of the development of simian ATL-like disease with the monoclonal integration of the STLV-I provirus genome, it should be indicated that STLV-I has similar leukemogenicity to human T-cell leukemia virus type I, and so STLV-I infection in African green monkeys will be useful as an animal model of human ATL.

Animals↗
PubMed1987

Modulation of fibroblast proliferation by postsurgical macrophages.

Macrophages and fibroblasts are major components of postsurgical peritoneal repair. In order to understand the interaction between these two cell types, we studied the effects of spent macrophage culture media on fibroblast proliferation. Rabbits underwent resection and reanastomosis of their small intestine. Peritoneal exudative cells (PEC) were then collected from these animals on postoperative Days 4, 7, and 28 and from nonsurgical controls. PEC (5 X 10(5) cells/ml) were cultured in M-199 with 3% fetal calf serum. After 48 hr the spent media from the cultured PEC were harvested, centrifuged (200g for 10 min), and stored (medium: M-D0, D4, D7, D28). A second group of rabbits underwent peritoneal wall abrasion followed by collection of fibroblasts directly from the site of injury on postoperative Days 1, 4, and 7. After Day 7 of culture, fibroblasts were resuspended and seeded into dishes (1 X 10(5) cells in 1 ml medium), to which was added 1 ml of spent PEC culture medium. After 24 hr of incubation, 1 muCi [3H]thymidine was added for an additional 18 hr. Fibroblasts were then collected and the amount of [3H]thymidine incorporated into trichloroacetic acid-precipitable material was quantitated. In one protocol, fresh M-199 with 3% fetal calf serum was used, and in another protocol, "U-medium" (which was previously incubated for 48 hr with fibroblasts) was used. The cytology of the PEC was determined by Wright's staining, nonspecific esterase activity, and phagocytosis. At least 80% of the peritoneal exudative cells were identified as macrophages. Postsurgical Day 7 fibroblasts demonstrated greater [3H]thymidine incorporation compared to fibroblasts from postoperative Days 1 and 4.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Human T-cell leukemia virus type I isolates from Gabon and Ghana: comparative analysis of proviral genomes.

Two isolates of human T-cell leukemia virus type I (HTLV-I) were obtained from lymphocyte cultures of a healthy carrier in Gabon and another in Ghana. Their proviruses were analyzed by Southern blot hybridization and compared with prototypical HTLV-I isolated in Japan and the United States. The provirus genomes of both strains were highly homologous to the prototype HTLV-I along the whole viral genome. The restriction endonuclease sites of the Ghanian isolate were almost identical with those of the prototype HTLV-I, but 10 of 26 sites of the Gabonese isolate were different from those of the prototype. Furthermore, the restriction map of the Gabonese isolate resembled those of a simian T-cell leukemia virus (STLV-I) isolated from a chimpanzee from Sierra Leone and a variant of HTLV-I from Zaire (HTLV-Ib) more closely than those of any other known HTLV-I. These results indicated the existence of some unique strains of HTLV-I transmitted among African people, and the importance of clarifying the origin and transmission of HTLV group viruses.

Biological Evolution↗