Immunological and virological investigation in patients with lymphoadenopathy syndrome and in a population at risk for acquired immunodeficiency syndrome (AIDS), with particular focus on the detection of antibodies to human T-lymphotropic retroviruses (HTLV III)

Editorial to the Special Issue "Clinical Immunology in Italy, with Special Emphasis to Primary and Acquired Immunodeficiencies: A Commemorative Issue in Honor of Prof. Fernando Aiuti"

Fernando Aiuti (Figure 1), born in Urbino on 8 June 1935, suddenly died on 9 January 2019, leaving a great void not only among his family members and those who knew him and appreciated his great humanity and acute intelligence, but in the entire immunological scientific community [...].

Persistent nonproductive infection of Epstein-Barr virus-transformed human B lymphocytes by human immunodeficiency virus type 1

We have studied the interaction of different strains of human immunodeficiency virus type 1 (HIV-1) with an Epstein-Barr virus-transformed human B-lymphocyte line, X50-7. Previously we found that some HIV-1 strains replicated rapidly and were exclusively cytolytic; others induced persistent noncytopathic infection associated with continued shedding of extracellular virus (K. Dahl, K. Martin, and G. Miller, J. Virol. 61:1602-1608, 1987). We now describe a third form of cell-virus relationship in which infection by strain IIIB is maintained in a highly cell-associated state in a small subpopulation (less than 2%) of X50-7 cells. Neither viral subcomponents nor infectious virus was detectable in culture supernatants; however, the carrier lines were fusogenic and HIV-1 could be recovered following prolonged cocultivation with susceptible cells. In these chronic carrier cultures, virions were not seen budding at the cell surface, but a few were found within cytoplasmic vesicles. HIV-1 infection of first- and second-generation cell subclones of the carrier cell line rapidly evolved from a productive to a cell-associated state. There were low levels of HIV DNA, and RNA in the fusogenic secondary clones, but most clones lacked HIV-1 DNA, failed to express HIV-1 RNA, and exhibited no properties associated with HIV-1 infection. The experiments indicate that HIV-1 can be sequestered in human B lymphocytes. The cell cloning experiments introduce the possibility that the HIV-1 provirus may be lost from some lymphocytes.

Deficiency of natural killer activity, but not of natural killer binding, in patients with lymphoadenopathy syndrome positive for antibodies to HTLV-III

Blood lymphocytes (BL) of eleven patients with lymphoadenopathy syndrome (LAS) were studied for natural killer (NK) activity against the K562 cell line (using both the standard 51Cr release assay and the single-cell cytotoxicity assay on poly-L-lysine-coated coverslips) and for surface phenotype (employing OKT4, OKT8 and Leu7 monoclonal antibodies). A significant reduction in NK activity and in NK active cells was detected, while the percentage of target binding cells was not affected. Furthermore, the OKT4/OKT8 ratio was found to be inverted, and the Leu7+ subpopulation expanded. The patients had high titers of anti-HTLV-III antibodies. This study indicates that defective NK activity in LAS is secondary to an abnormality in the lytic event itself and not in target binding.