Leukemia-Specific DNA Sequences in Leukocytes of the Leukemic Member of Identical Twins

138

A human type C retrovirus, designated HTLV, previously was isolated from or identified in some patients with leukemias and lymphomas of mature T lymphocytes. HTLV is genetically and serologically distinct from any known animal retroviruses. The absence of HTLV proviral sequences in DNA from normal humans showed that HTLV is not a ubiquitous endogenous (germ-line transmitted) virus ofhumans. Antibodies to HTLV core proteins have been identified in some people with T-cell neoplasias and are particularly prevalent in Japanese with adult T-cell leukemia, suggesting that HTLV is acquired horizontally. However, it was possible that HTLV is transmitted through the germ line of some (possibly rare) families and is then expressed in the HTLVpositive malignancies. An opportunity to study this question was provided by the development of several T-cell lines and a B-cell line from one HTLV-positive patient with a cutaneous T-cell lymphoma. Here we report that HTLV proteins or nucleic acids (or both) are found in three independently derived T-cell lines, all shown by HLA typing to have originated from the patient. In contrast, the B-cell line, the identity of which was also ascertained by HLA typing, contained no detectable HTLV protein, RNA, or proviral DNA. Because the sensitivity of the latter assay is more than sufficient to detect one proviral equivalent per haploid genome, the results indicate that HTLV was not transmitted to this patient through the germ line but rather was acquired by infection.The discovery (1,2) and purification (3) of T-cell growth factor (TCGF) has made it possible to grow relatively mature human T cells from normal (1, 2) and neoplastic (4) sources routinely in liquid suspension culture for long periods. We have identified a human type C retrovirus in cultured T cells from several patients with leukemia-lymphoma. of relatively mature T cells. In some instances, the virus (called HTLV) has been constantly produced by these T cells (5, 6) which have become independent of TCGF and established as permanent cell lines, apparently because of eventual constitutive release of TCGF (7). In two instances, the virus has been characterized in detail (5, 6). HTLV is not an endogenous virus ubiquitous in human germ lines (8) and is readily distinguishable from the known animal retroviruses, including those from subhuman primates (8-10). Antibodies to two HTLV proteins, p24 and p19, have also been found in sera from a few other patients with T-cell malignancies in the United States (11, 12), in a high percentage of patients with adult T-cell leukemias and other leukemias in Japan (13,14), and, more recently, in T-cell malignancies from many other parts of the world (unpublished data).Recently, workers in Japan have also shown that a retrovirus is associated with these diseases in southern Japan (15-17), and we have ascertained that this virus is HTLV (or a closely related strain) (unpublished data). Here we show that HTLV is present in some of the T cells in three independently derived T-cell lines fr...

Section: Resultssupporting

confidence: 81%

Human T-cell leukemia-lymphoma virus (HTLV) is in T but not B lymphocytes from a patient with cutaneous T-cell lymphoma.

Gallo¹,

Mann²,

Broder³

et al. 1982

138

“…With human leukemic cDNA as a probe, it has recently been demonstrated that there are sequences present in the nuclear DNA of leukemic WBC that are not detectable in normal WBC (7,8). Although the sequences unique to leukemic nuclear DNA were detected by a probe made from a leukemic WBC extract potentially enriched for RNA tumor virus-like particles, there was and has been no direct evidence that linked these sequences specifically with an actual RNA tumor virus.…”

Section: Discussionmentioning

confidence: 98%

“…With complementary [3H]-DNA (cDNA) prepared from human leukemic WBC particulate fractions, it has also been shown that there are DNA sequences in human leukemic WBC that do not appear to be present in normal WBC (7,8). However, it has not been shown whether these human leukemia-specific DNA sequences are either: (1) complementary to any part of a known RNA tumor virus genome or (2) identical to RLV or AKR tumorspecific sequences.…”

mentioning

confidence: 99%

Sequences Present in Both Human Leukemic Cell Nuclear DNA and Rauscher Leukemia Virus

Baxt¹

1974

DNA synthesized by particulate fractions from human leukemic white blood cells has been subfractionated by hybridization to Rauscher leukemia virus 70S RNA followed by hydroxylapatite chromatography. The Rauscher-leukemia-virus-specific DNA fraction is shown to be complementary only to sequences present in the nuclear DNA of Balb/c mouse spleens infected by this virus and the nuclear DNA from human leukemic white blood cells, and not to sequences present in the nuclear DNA of normal Balb/c mouse spleens or the nuclear DNA of normal human white blood cells. EDTA, pH 7.4, 0.01 M NaCl, 4% sodium dodecyl sulfate. The fractions eluting in the void region of the column (10 ml) were pooled, brought to 0.4 M NaCl, and the cDNA was precipitated with ethanol as above. The pellet was resus- RNA

“…These included the morphology of the isolated particles, the density of the particles and the cores, the RNA-directed polymerase, and the synthesis of RNA-DNA hybrids on the 705 RNA present in the isolated particles. The (16) and Gallo and his collaborators (6,17), in human leukemic cells.…”

Section: Discussionmentioning

confidence: 99%

Oncornavirus-like particles released from arginine-deprived human lymphoblastoid cell lines.

Kotler¹,

Balabanova²,

Weinberg³

et al. 1975

TypeC RNA tumor virus particles were released from three different human lymphoblastoid cell lines after incubation in arginine-deficient medium. The released virus-like particles were characterized by (a) their ability to band in sucrose gradients at a density of 1.18-1.18 g/ml; (b) the presence of an RNA-directed DNA polymerase activity resembling that of the oncornaviruses; and (c) isolation of cores that and at a density of 1.26-1.27 g/ml in sucrose gradients. Examination of the arginine-deprived human lymphoblastoid cell line strain P3HR-1 by electron microscopy revealed the presence of C-type particdes in the intracellular spaces. The search for oncornaviruses associated with different forms of human cancer depends in most instances on the induction in vitro of the latent virus genomes present in the cancer cells. It has been demonstrated that arginine deprivation leads to the induction of oncornavirus synthesis in transformed cells (1-3). Rat cells transformed by the B77 strain of Rous sarcoma virus (RSV) released C-type particles into the medium when deprived of arginine (1). These particles were capable of transforming chick and rat cell cultures (M. Kotler, D. Boettiger, and R. Weiss, to be published). Incubation of leukocytes from patients with lymphatic leukemia in an arginine-deficient medium also resulted in the synthesis and release of C-type virus particles (2, 3). The spontaneous production of similar oncornavirus particles was demonstrated after short-term cultivation of leukemic bone-marrow cells (4, 5) in three myeloblastic cell lines from the peripheral blood of a patient with acute myelogenous leukemia (6) and from a human adenocarcinoma cell line (7).It was therefore of interest to determine the effect of arginine deficiency on lymphoblastoid cell lines. For