Human T-Cell Lymphotropic Virus Type 1 Tax among American Blood Donors

In the United States, all blood used for transfusion is tested for the presence of antibodies to the structural components of the human T-cell lymphotropic viruses types 1 and 2 (HTLV-1 and -2). Based on such serologic tests, the prevalence of HTLV-1 infection is estimated to range from 0.016 to 0.1%. As a consequence of studies of patients with mycosis fungoides and some of their healthy relatives who are antibody negative but were found to carry the tax sequence of HTLV-1 in their lymphocytes and who had antibodies to the p40(tax) protein, a study was undertaken to determine the prevalence of the “tax-only” state in 250 healthy blood donors and other volunteers. Using PCR and Southern analysis for cell lysates and using Western blotting for plasmas, 8.6% of the blood donors proved to be tax sequence positive and antibody positive. Sequence analysis of specimens from 22 individuals proved that 20 of the sequences were homologous with that of HTLV-1 while 2 resembled the HTLV-2 sequence. The latter were obtained from volunteers of Indian origin. The possible clinical significance of the tax-only carrier state is discussed.

美国所有用于输血的血液均需检测是否存在针对人类T细胞嗜淋巴细胞病毒1型和2型（HTLV-1与HTLV-2）结构组分的抗体。基于此类血清学检测，HTLV-1感染的流行率估计为0.016%至0.1%。鉴于此前针对蕈样肉芽肿患者及其部分健康亲属的研究发现，这些亲属血清抗体检测呈阴性，但淋巴细胞中携带HTLV-1的tax序列，且存在针对p40(tax)蛋白的抗体，本研究旨在明确250名健康献血者及其他志愿者中“仅tax阳性”状态的流行率。通过对细胞裂解液采用聚合酶链式反应（Polymerase Chain Reaction, PCR）与Southern印迹分析，对血浆标本采用免疫印迹（Western Blotting）检测，结果显示8.6%的献血者同时呈现tax序列阳性与抗体阳性。对22份个体样本的序列分析表明，其中20份序列与HTLV-1序列同源，剩余2份序列与HTLV-2序列相似。后两份样本均来自印度裔志愿者。本文还讨论了“仅tax阳性”携带状态可能的临床意义。