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Human Monoclonal Antibodies and Immune Modulation in Viral Hepatitis, Schistosomiasis, and HTLV Infection
Published in Thomas F. Kresina, Immune Modulating Agents, 2020
Thomas F. Kresina, Garry A. Neil, Steven K. H. Foung
The utility of human monoclonal antibodies for diagnostic purposes is illustrated by our investigation to identify and characterize immunogenic domains of human T-lymphotropic type I and type II viruses (HTLV-1 and HTLV-11). These viruses are human retroviruses that are increasingly recognized as important pathogens. Human T-lymphotropic virus-I is the causative agent of adult T-cell leukemia/lymphoma and a chronic neurological disorder termed HTLV-I-associated myelopathy or tropical spastic paraparesis (HAM/TSP) [37,38]. It has been also linked to uveitis and possibly to polymyositis. Although HTLV-II is structurally similar to HTLV-I, diseases associated with HTLV-II have been more difficult to identify and are just beginning to emerge. We and other investigators have recently [39–42] reported on patients with HAM/TSP-like illnesses who are seropositive for HTLV-II and whose peripheral blood lymphocytes were demonstrated to contain HTLV-II by polymerase chain reaction (PCR) analysis.
HIV and AIDS
Published in Rae-Ellen W. Kavey, Allison B. Kavey, Viral Pandemics, 2020
Rae-Ellen W. Kavey, Allison B. Kavey
Gallo’s laboratory was well prepared for this investigation after their years of experience culturing and growing T-cells in the process of identifying HTLV-1 and subsequently an additional retrovirus, HTLV-2. By May 1982, the laboratory had begun trying to identify a retrovirus in the blood of AIDS patients. Meanwhile, Luc Montagnier, a French virologist at the Pasteur Institute, was studying the lymph nodes of patients with AIDS. In January 1983, his laboratory identified reverse transcriptase enzyme activity in lymph node cells from a gay man with generalized lymphadenopathy.33 At that time, retroviruses were the only entity known to use reverse transcriptase – and the only retroviruses known to attack humans were HTLV-1 and HTLV-2.
Human T lymphotropic virus type 1 (HTLV-1)
Published in Avindra Nath, Joseph R. Berger, Clinical Neurovirology, 2020
Although HTLV-1 and HTLV-2 share similar genome structure, routes of transmission, and replication pattern, they differ in epidemiology and disease associations. HTLV-2 is prevalent among indigenous populations in Africa, Indian-American tribes in Central and South America, as well as among drug users in Europe and North American [49]. A 14-year longitudinal study of HTLV-2 infected patients identified increase in lymphocyte count and platelets over time compared to uninfected healthy participants [50]. Other studies of HLTV-2 clinical manifestations have largely been confounded by concomitant HIV-1 infection or IV drug abuse making the establishment of clear relationship with other manifestations such as neurological disease difficult. Case reports presenting an association with myelopathy or spastic ataxia and HTLV-2 highlight the need for studying these associations in larger patient populations [51].
Pathogenicity and virulence of human T lymphotropic virus type-1 (HTLV-1) in oncogenesis: adult T-cell leukemia/lymphoma (ATLL)
Published in Critical Reviews in Clinical Laboratory Sciences, 2023
Sanaz Ahmadi Ghezeldasht, David J. Blackbourn, Arman Mosavat, Seyed Abdolrahim Rezaee
Previously, our studies have revealed that the general population’s seroprevalence of HTLV-1 cosmopolitan subtype A (HTLV-1A) infection in Iran is around 1–5% [13,14]. Hedayati-Moghaddam et al. have published two comprehensive systematic reviews emphasizing HTLV-1 and HTLV-2 prevalence in blood donors and the general population in Iran. The virus is endemic in six provinces, particularly Razavi Khorasan (a pilgrimage region) and North Khorasan [15,16]. However, after 29 years of HTLV-1 identification in Razavi Khorasan [17], the exact incidence of HAM/TSP and ATLL was not evaluated as it needs a prospective cohort. Nevertheless, we can consider the average incidence of HAM/TSP and ATLL in HTLV-1-infected subjects (2–5%) [1]. The population of Razavi Khorasan is 6.3 million, and North Khorasan is 863,000 (https://irandataportal.syr.edu/census/census-2016), with a prevalence of 2.5% for HTLV-1 and the incidence of 3% toward HAM/TSP or ATLL, then the estimated incidence for HTLV-1-associated diseases in these provinces should be:
A genetic IFN/STAT1/FAS axis determines CD4 T stem cell memory levels and apoptosis in healthy controls and Adult T-cell Leukemia patients
Published in OncoImmunology, 2018
Ricardo Khouri, Gilvanéia Silva-Santos, Tim Dierckx, Soraya Maria Menezes, Daniele Decanine, Kristof Theys, Aline Clara Silva, Lourdes Farré, Achiléa Bittencourt, Massimo Mangino, Mario Roederer, Anne-Mieke Vandamme, Johan Van Weyenbergh
Adult T-cell leukemia (ATL) is characterized by circulating CD4+CD25+ T-cells1 and is etiologically linked to infection with Human T-cell Leukemia Virus 1 (HTLV-1), the first isolated human pathogenic retrovirus.2 The estimated lifetime risk is about 5% in infected individuals,3 with a long incubation period after HTLV-1 infection, therefore infection early in life is fundamental in the development of ATL.4 ATL is classified according to clinical and laboratory criteria as smoldering, chronic, lymphoma, or acute subtypes.5 The median survival time for acute and lymphoma (aggressive) subtypes is less than one year, whereas patients with chronic and smoldering (indolent) subtypes survive longer.6 In addition, an atypical aggressive, primary cutaneous tumoral form (PCT) of ATL with a shorter survival has been described.7 The exceptional oncogenicity of HTLV-1, as compared to other viruses or infectious agents,8 or even to its closest relative HTLV-2,9, is most likely due to its ability to deregulate several host cell signaling pathways. In sharp contrast to HIV, plasma viral load for HTLV-1 is mostly undetectable and proviral replication is driven by spontaneous lymphoproliferation (reviewed in3), which implies that ATL might be explained mainly by host factors such as immune response and host genetics.
Assessment of risk factors associated with HTLV-1/-2 infection among people living with HIV/AIDS in Bauchi State, Nigeria
Published in Alexandria Journal of Medicine, 2020
Adamu Babayo, Idris Nasir Abdullahi, Mansur Bala Safiyanu, Hafeez Aderinsayo Adekola, Jamila Nasir Usman
Human T-cell lymphotropic virus (HTLV) is associated with shorter survival of HIV coinfected persons due to masked immunosuppression [1]. Coinfection of HTLV and HIV is common in areas endemic for HTLV because these viruses have similar transmission routes, such as unprotected sexual intercourse, breastfeeding, blood transfusion and organ/tissue transplantation, and injectable drug use [1]. Studies suggest that people living with HIV (PLWHIV) infected with HTLV-1 are more likely to develop myelopathies and neurological disease [2]. However, the effect of HTLV-2 in HIV-positive individuals is unclear [3]. In addition, coinfection may mask the diagnosis of acquired immunodeficiency syndrome (AIDS), since CD4 + T-cell counts significantly increase in affected persons [4,5].