In order to evaluate the protective role of the maternal antibody against mother-to-child transmission of HTLV-I, we followed a total of 780 children born to HTLV-I carrier mothers by investigating the level of anti-HTLV-I antibody transferred in utero, decline of the maternal antibody and seroconversion in post-natal life. The anti-HTLV-I antibody was positively detected within the first 3-6 months of life and declined at 6-12 months after birth in all children. After the maternal antibody declined, seroconversion occurred in some of the children following either breast feeding or bottle feeding. The seroconversion rates of short-term (less than or equal to 6 months) and long-term (greater than or equal to 7 months) breast feeders were 4.4% (4/90 cases) and 14.4% (20/139 cases), and the rate of bottle feeders was 5.7% (9/158 cases). Long-term breast feeding yielded more seroconverters than short-term breast feeding; 14.4% (20/139 cases) vs. 4.4% (4/90 cases), RR = 3.68, p = 0.018. The seroconversion rate of short-term breast feeders was nearly equal to that of bottle feeders; 4.4% (4/90 cases) vs. 5.7% (9/158 cases), RR = 0.770, p = 0.471. When neonatal lymphocytes were cultured with breast milk cells of HTLV-I carrier mothers, the in vitro infection of HTLV-I was inhibited by the addition of HTLV-I-seropositive cord-blood plasma. Our results suggest that the maternal antibody may inhibit HTLV-I infection by short-term breast feeding but not by long-term breast feeding after decline of the maternal antibody.

Genetic risk for adult T cell leukemia (ATL) has been implicated by ethnic and familial segregation of ATL patients from HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). To clarify the genetic risk for ATL, we characterized HLA class I alleles of ATL patients and analyzed the anchor motifs of HTLV-1 peptides binding to HLA class I molecules, using 291 lines of anti-HTLV-1 CD8(+) cytotoxic T lymphocytes (CTLs) generated in vitro with a total of 165 synthetic peptides for HTLV-1 Tax and Env proteins. Allele frequencies of HLA-A*26, B*4002, B*4006, and B*4801 were significantly higher in ATL patients than in HAM/TSP patients and asymptomatic HTLV-1 carriers in southern Japan. CD8(+) CTL analysis revealed the HTLV-1 Tax peptide sequence to completely lack anchor motifs of peptides binding to HLA-A*26,B*4002, and B*4006 molecules but to possess one anchor for HLA-B*4801, while the HTLV-1 Env peptide sequence had many anchor motifs for HLA-A*26, B*4002, B*4006, and B*4801 molecules. Most ATL patients featured heterozygous HLA class I alleles composed of HLA-A*26, B*4002, B*4006, and B*4801, with a lower number of HTLV-1 Tax peptide anchor motifs and epitopes generating anti-HTLV-1 Tax CD8(+) CTLs than individuals possessing other HLA alleles. The relationship between Tax epitope and ATL incidence was verified by the significantly decreased number of HTLV-1 Tax epitopes in ATL patients compared with asymptomatic HTLV-1 carriers (p < 0.01) as well as late onset ATL patients (p < 0.001). These results indicate that HLA-A*26, B*4002, B*4006, and B*4801 alleles predispose to ATL because of the limited recognition of HTLV-1 Tax peptide anchor motifs and epitopes capable of generating anti-HTLV-1 Tax CD8(+) CTLs.

The worldwide geographic and ethnic clustering of patients with diseases related to human T-cell lymphotropic virus type I (HTLV-I) may be explained by the natural history of HTLV-I infection. The genetic characteristics of indigenous people in the Andes are similar to those of the Japanese, and HTLV-I is generally detected in both groups. To clarify the common origin of HTLV-I in Asia and the Andes, we analyzed HTLV-I provirus DNA from Andean mummies about 1,500 years old. Two of 104 mummy bone marrow specimens yielded a band of human beta-globin gene DNA 110 base pairs in length, and one of these two produced bands of HTLV-I-pX (open reading frame encoding p40x, p27x) and HTLV-I-LTR (long terminal repeat) gene DNA 159 base pairs and 157 base pairs in length, respectively. The nucleotide sequences of ancient HTLV-I-pX and HTLV-I-LTR clones isolated from mummy bone marrow were similar to those in contemporary Andeans and Japanese, although there was microheterogeneity in the sequences of some mummy DNA clones. This result provides evidence that HTLV-I was carried with ancient Mongoloids to the Andes before the Colonial era. Analysis of ancient HTLV-I sequences could be a useful tool for studying the history of human retroviral infection as well as human prehistoric migration.

Partial cDNA clones encoding human cytosolic aldehyde dehydrogenase (ALDH1) and mitochondrial aldehyde dehydrogenase (ALDH2) were isolated from a human liver cDNA library constructed in phage Agtll. The expression library was screened by using rabbit antibodies against ALDH1 and ALDH2. Positive clones thus obtained were subsequently screened with mixed synthetic oligonudeotides compatible with peptide sequences of ALDH1 and ALDH2. One of the positive clones for ALDH1 contained an insertion of 1.6 kilobase pairs (kbp). The insert encoded 340 amino acid residues and had a 3' noncoding region of 538 bp and a poly(A) segment. The amino acid sequence deduced from the cDNA sequence coincided with the reported amino acid sequence of human ALDH1 [Hempel, J., von Bahr-Lindstrom, H. & Jornvall, H. (1984) Eur. J. Biochem. 141, 21-35], except that valine at position 161 in the previous amino acid sequence study was found to be isoleucine in the deduced sequence. Since the amino acid sequence of ALDH2 was unknown, 33 tryptic peptides of human ALDH2 were isolated and sequenced. Based on the amino acid sequence data thus obtained, a mixed oligonucleotide probe was prepared. Two positive clones, AALDH2-21 and AALDH2-36, contained the same insert of 1.2 kbp. Another done, AALDH2-22, contained an insert of 1.3 kbp. These two inserts contained an overlap region of 0.9 kbp. The combined cDNA contained a sequence that encodes 399 amino acid residues, a chain-termination codon, a 3' untranslated region of 403 bp, and a poly(A) segment. The deduced amino acid sequence was compatible with the amino acid sequences of the tryptic peptides. The degree of homology between human ALDH1 and ALDH2 is 66% for the coding regions of their cDNAs and 69% at the protein level. No significant homology was found in their 3' untranslated regions.Liver aldehyde dehydrogenase (ALDH; aldehyde:NAD+ oxidoreductase, EC 1.2.1.3) is considered to play a major role in alcohol metabolism. Two major and several minor isozymes exist in the livers of mammals, including man.

To identify and characterize mRNAs which are abundant in established cell lines, but less so in the corresponding parental counterparts, a cDNA library was constructed from poly(A)+RNA of Balb/c3T3 cells. We screened this cDNA library by differential colony hybridization using single-stranded cDNAs from Balb/c3T3 cells and mouse embryo fibroblasts (MEF), and obtained four cDNA clones, out of 8,300 clones. One such clone, named pEL98, corresponding to mRNA of approximately 600 nucleotides, was further characterized. The entire nucleotide sequence of the cDNA insert in the pEL98 revealed a single open reading frame that encodes a 101 amino acid of putative protein (hereafter referred to as the pEL98 protein). pEL98 protein is highly homologous to both alpha and beta subunits of bovine S-100 protein (49 and 47% homology, respectively), a protein belonging to the family of calcium binding proteins. pEL98 protein is also homologous to several S-100 related proteins such as "calcyclin," a product of growth-regulated human gene 2A9, porcine p11 (or p10), the small subunit of a protein complex which serves as a major substrate of tyrosine kinase, and human cystic fibrosis antigen (CFAg). The amounts of transcript of pEL98 were increased in murine cells transformed with both activated oncogene and chemical carcinogen.

Green tea polyphenols (TEA) are known to exhibit antioxidative activity as well as tumor-suppressing activity. In order to examine the tumor-suppressing activity of TEA against adult T-cell leukemia (ATL), we cultivated peripheral blood T lymphocytes of ATL patients (ATL PBLs), an HTLV-I-infected T-cell line (KODV) and healthy controls (normal PBLs) for 3 days in the presence of TEA and its main constituent, epigallocatechin-3-gallate (EGCg), to measure cell proliferation and apoptosis, and to quantitate mRNAs of HTLV-I pX and β β β β-actin genes of the cultured cells. Growth of ATL

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