Human Cytomegalovirus Infection of the Major Leukocyte Subpopulations and Evidence for Initial Viral Replication in Polymorphonuclear Leukocytes from Viremic Patients

Abstract

Fourteen immunocompromised patients were examined for viremia, pp65 and p72 antigenemia, and presence of viral DNA in leukocyte fractions of polymorphonuclear leukocytes (PMNL), monocytes/macrophages (M/M), and B and T lymphocytes after purification by fluorescence-activated cell sorting. Nearly all PMNL and M/M fractions were positive for DNA and pp65 antigenemia, while p72 antigenemia was detected in 73% and 62%, respectively. The virus isolation rate was 45% from PMNL and 17% from M/M. T lymphocytes were positive for DNA in 50% of cases and for pp65 and p72 antigenemia in only 11%, while B lymphocytes were DNA-positive in 43% of samples and consistently negative for antigenemia; neither T nor B lymphocytes had virus isolated. Immediate-early (IE)1 RNA was present in 23 (85.2%) of 27 dextran-enriched DNA-positive p72-positive PMNL samples and, in sequential PMNL samples from two heart-transplanted patients, was detected during peak infection in association with p72. Thus, PMNL and M/M are the subpopulations primarily involved in HCMV infection; PMNL may undergo IE replicative events and are not merely passive carriers of phagocytized viral material.

Presence of human cytomegalovirus (HCMV) immediate early mRNA but not ppUL83 (lower matrix protein pp65) mRNA in polymorphonuclear and mononuclear leukocytes during active HCMV infection

“…The presence of IE mRNA in polymorphonuclear cells (Gerna et al, 1992;Bitsch et al, 1993) and mononuclear cells (Bitsch et al, 1993), and of mRNA encoding late HCMV proteins (Bitsch et al, 1993;Gozlan et al, 1993) in these leukocyte fractions from patients with an active HCMV infection has also been demonstrated by RT-PCR. However, the leukocytes in these RT-PCR studies were isolated via density gradient centrifugation or starch or dextran sedimentation prior to RNA extraction, and our results demonstrate that circulating late-stage HCMV-infected endothelial cells may well have been present in these cell fractions.…”

The pentameric complex of human Cytomegalovirus: cell tropism, virus dissemination, immune response and vaccine development

“…A detailed analysis of the major leukocyte subpopulations from viremic patients showed that nearly all PMNL and M/M fractions were positive for viral DNA and pp65-antigenemia, while the virus isolation rate was 45 % from PMNL and 17 % from M/M samples [20]. The simultaneous use of HCMV pp65 L-antigenemia, L-viremia and L-DNAemia to detect HCMV in leukocytes [14] allowed the first detection of a sharp drop in the prevalence of HCMV infections in HIV-infected patients following the introduction of highly active antiretroviral therapy [21].…”

Fibroblasts, epithelial cells, endothelial cells and smooth muscle cells are major targets of human cytomegalovirus infection in lung and gastrointestinal tissues

“…Staining of cell-specific marker proteins and analysis of sorted blood cell fractions have improved the analysis of HCMV cell tropism. Recent reports described the presence of infected monocytes, endothelial cells and polymorphonuclear cells in the peripheral blood (Gerna et al, 1992b;Grefte et al, 1993a, b;Percivalle et al, 1993). However, the role of these cell types in the infection of organ tissues remains unclear.…”