During 1994 and 1995, the prevalence of hepatitis C virus (HCV) and its genotypes were studied in several rural and urban populations in three West African countries: Guinea, Burkina Faso, and Benin. The following groups were screened for antibodies to HCV (anti-HCV): 459 villagers in the forest region of Guinea; 965 individuals in urban, suburban, and rural populations of the Bobo Dioulasso area, Burkina Faso; and 582 blood donors in Cotonou, Benin. In Benin, 60 patients with sickle cell anemia (30 with and 30 without history of multiple transfusion) and 13 hospital patients with liver disease were also tested. RT-PCR detection of HCV-RNA was carried out on all anti-HCV positive samples, followed by genotyping and sequencing of unrecognized subtypes. The prevalence rates of anti-HCV were 1.1% in the Guinean population group, 1.4% among blood donors in Benin, and 4.9% in residents of Burkina Faso. In patients with sickle cell anemia, five of the 30 polytranfused patients (17%) had anti-HCV, whereas none of the patients without a history of blood transfusion had anti-HCV (P < 0.05). Among the 13 patients with liver disease, five had anti-HCV, of whom four had history of blood transfusion. HCV-RNA was detected in 41 anti-HCV positive sera. All belonged to genotypes 1 or 2, with a high genomic diversity; 18 different subtypes were identified, including 2c, 2d, and 16 new subtypes. Such genetic diversity poses a challenge for vaccine development and also implies that HCV infection is long-established in these West African regions.

The protocol selected in the initial phase, now available as a WBC-reduction system, results in platelet concentrates with very low residual WBC levels. This satisfies even the most stringent criteria for WBC reduction in platelets, without the platelet loss typically seen with conventional fiber filtration.

By using target cells that expressed isolated env, gag, p27"'f, or p23vaf molecules introduced by recombinant vaccinia viruses containing genes encoding these polypeptides, it was possible to identify env, gag, p27"ef, and p23v1f as cytolytic target antigens for freshly isolated blood cells from human immunodeficiency virus 1 (HIV-1) seropositive patients. Most of the patients tested (95%) manifested a specific cytotoxic activity against vaccinia virus-env-infected target cells. The env-specific cytotoxic activity was not restricted by the major histocompatibility complex and was not mediated by T lymphocytes, as shown by the absence of blocking effect with an anti-CD3 monoclonal antibody and by the inefficiency of CD3+, CD8+, or CD4+ and CD8+ depletion to reduce the cytotoxic activity against the env-expressing target cells. In the same conditions, the cytotoxic activity specific for gag was abrogated and gag major histocompatibility complex-restricted cytotoxic T lymphocytes were detected in 85% of the subjects tested. Therefore, in a HIV-1 seropositive subject, distinct types of effector cells mediate the lysis of target cells expressing gag and env proteins. * Corresponding author. (100 U/ml), streptomycin (100 p.g/ml), HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid) (20 mM), and 10% heat-inactivated fetal calf serum (Biological Industries, Kibbutz Haemek, Israel) (RPMIc) was used for most assays. The mouse EL4 cell line was a gift from G. Milon (Institut Pasteur, Paris, France), the mouse P815 cell line was a gift from D. Juy (Institut Pasteur, Paris, France), and the human K562 cell line was a gift from E. Gomard (Hopital Cochin, Paris, France). Monoclonal antibodies and complement. Monoclonal antibody anti-Leullb, (which recognizes the CD16 antigen) was purchased from Becton Dickinson, Grenoble, France. Monoclonal antibodies directed against the CD3, CD4, and CD8 antigens were from Ortho Diagnostics Systems, Roissy, France (OKT3, OKT4, and OKT8, respectively) or Immunotech, Marseille, France (IOT3, IOT4, and IOT8a, respectively). The low Tox H rabbit complement was purchased from Cedarlane, Tebu, France. Viruses. The different recombinant viruses used to infect the target cells have been previously described, except for the vaccinia virus (VV) Q recombinant (12, 19-21; G. Rautmann et al., in press). Briefly, the viruses used were the wild-type (WT) VV, strain Copenhagen, or various recombinants encoding either the middle T antigen of the polyomavirus (as a control) or the env (gpl60), gag (p55), p27"1f (F or 3' open reading frame) or p23"f (Q or sor) antigens of the HIV-1/BRU isolate (recombinant VV TG 1139, VV TG 1144, VV TG 1147, or VV TG 1160, respectively). The VV Q recombinant was constructed as follows: the EcoRI fragment from the plasmid pJ 19-13 (37) containing the coding sequence from the vif (Q) gene of HIV-1 was cloned in a M13 vector, and a BglII site was created upstream of the initiation codon by site-directed mutagenesis by using the oligonucleotide 5'TCCCTAAAGATCTTT3'. The resul...

Liver dysfunction is common in allogeneic bone marrow graft recipients, but no systematic studies of pre- and posttransplantation liver biopsies have been performed to identify and compare hepatic lesions. This study involved 25 consecutive patients who had undergone serial viral screening tests, liver tests, and pre- and posttransplantation liver biopsy. The aims were to ascertain the origin of liver disorders prior to bone marrow transplantation, to determine the mechanism and severity of liver dysfunction occurring early after transplantation, and to identify a possible relationship between pre-existing liver lesions and the frequency and nature of early liver dysfunction after transplantation. Pretransplantation biochemical liver tests were abnormal in 72% of patients, despite the absence of clinical liver disease. Eleven patients had chronic viral hepatitis B or C. Mild or moderate histological lesions were present in all the patients, with bile duct abnormalities in 48%, central vein abnormalities in 24%, sinusoidal fibrosis in 52%, portal fibrosis in 88%, portal necrosis in 52%, and parenchymal siderosis in 76%. After transplantation, fatal veno-occlusive disease occurred in two patients and biochemical abnormalities occurred in 24. Coded review of needle biopsy specimens failed to provide a single diagnosis. Histological lesions differed between pre- and posttransplantation biopsy specimens only by increased iron overload (96%, P<0.01). We conclude that pretransplant liver lesions contribute to hepatic dysfunction early after bone marrow transplantation, being very similar in nature and degree to lesions observed posttransplantation.

Ultraviolet (UV)-B irradiation abolishes lymphocyte functions (the ability to respond and to stimulate) in mixed lymphocyte culture (MLC). This effect may have practical application in the prevention or reduction of transfusion-induced alloimmunization against HLA class I antigens. To study this, platelet concentrates (PCs) were obtained with a cell separator, suspended in autologous plasma in a final volume of 400 mL, and transferred into a large (22 X 30 cm) cell culture bag. This plastic showed a good transmittance of UV-B rays at 310 nm (54%). PCs were placed between two quartz plates (surface of irradiation = 25 X 37 cm), and the two sides were irradiated simultaneously. Energy delivered to the surface of the plastic bag was automatically monitored. The ability to respond (in MLC and to phytohemagglutinin) and to stimulate allogeneic lymphocytes was completely abolished with energy of 0.75 J per cm2 (irradiation time less than 3 min). The temperature increase during irradiation was negligible. Platelet aggregation (collagen, adrenalin, ADP, arachidonic acid, ristocetin) was not impaired if UV-B energy was below 3 J per cm2. Recovery and survival of autologous 111In-labeled platelets were studied in four volunteers; no differences were found between UV-B-treated (1.5 J/cm2) platelets and untreated platelets. These results show that a large-scale clinical trial using UV-B-irradiated PCs to prevent HLA alloimmunization is feasible.