[Application of molecular biology to blood transfusion safety: the nucleic acid testing]. / Application de la biologie moléculaire à la sécurité virale transfusionnelle: le dépistage génomique viral.

Nucleic Acid Testing (NAT) for HIV-1 and HCV has been introduced in France and became mandatory for all homologous blood donations since July 1st 2001 in addition to serology screening. Previously, a feasibility study led to the selection of 2 technologies : a TMA based assay (Chiron) uses the Procleix HIV-/HCV assay on pools of 8 samples and a PCR based assay from BioMérieux-Roche which is a combination of an RNA extraction system (NucliSens, BioMérieux) with a fully automated system for nucleic acid amplification and detection (Cobas Amplicor, Roche). This system uses the Cobas Ampliscreen HCV test v.2.0 and the The Cobas Ampliscreen HIV test v1.5, on 24 sample pools. Pooling was required because single-donation testing is not yet feasible, as a result of the limitations in automation available for all current NAT technologies. The two technologies were easily implemented and showed nearly the same detection limit for HCV RNA and HIV-1 RNA. During a one-year period, from July 1st 2001 to June 30, 2002, out of the 2.5 million donations tested, the NAT yield resulted in one HIV-1 RNA positive-antibody negative donation and one HCV RNA positive-antibody negative donation. Two HIV NAT positive-antibody negative donations were missed by minipool NAT because a very low viral load. Moreover, the NAT implementation did not impact on blood component availability, including platelet concentrates.

Blood donors infected with the hepatitis B virus but persistently lacking antibodies to the hepatitis B core antigen.

BACKGROUND AND OBJECTIVES: Antibodies to the core of hepatitis B virus (anti-HBc) are considered to be the best serologically reliable markers of hepatitis B virus (HBV) infection. Through a national epidemiological survey, two young and first-time blood donors, originating from HBV-endemic areas, were identified as HBV carriers with an absence of anti-HBc reactivity. MATERIALS AND METHODS: We followed up these two subjects in order to investigate the evolution of their HBV serological profiles. Nucleotide sequencing was performed of the entire pre-C/C region of the strains infecting these donors. RESULTS: The same serological profile of active viral replication with an apparent persistent lack of anti-HBc and normal alanine aminotransferase (ALT) levels was found for both subjects throughout a follow-up of 19 months and 4 months, respectively. Neither donor was immunocompromised. Nucleotide sequence analysis of the pre-C/C region did not show mutations or deletions in encoded proteins. CONCLUSION: The hypothesis of an in utero HBV infection responsible for an immune tolerance to HBV seems to be the most probable explanation for this particular immunological situation. Such occurrences in the blood donor population are probably rare as less than 0.1% of hepatitis B surface antigen (HBsAg)-positive donors exhibit such a profile, in our experience. Moreover, this phenomenon does not impose a risk of HBV transmission by blood donation, as the exclusion of HBV-infected blood donation is based on HBsAg detection. However, such a risk might be encountered with the hepatitis C virus (HCV) for which at present only antibodies to HCV are screened.

A comparative evaluation of the sensitivity of five anti-hepatitis C virus immunoblot assays.

BACKGROUND AND OBJECTIVES: In order to compare sensitivity, five anti-hepatitis C virus (HCV) immunoblot assays were tested (Deciscan plus, Inno-Lia III, Matrix, Murex Western blot and RIBA-3). MATERIALS AND METHODS: The test panel (50 samples for each assay) included 6 anti-HCV-negative samples and 44 samples from 36 HCV-infected subjects. RESULTS: There were minor differences in core reactivity among the assays. The smallest number of NS3-reactive results occurred with the Murex and Matrix assays, and the smallest number of NS4 reactives with RIBA-3 and Matrix. Among the 20 discrepant results for NS5 there was one clear false-negative with Inno-Lia. Only 28 of the 50 samples of the panel gave the same results in all the assays: 5 negatives and 23 positives. One of the 6 negative samples were indeterminate in 3 assays. Eighteen of the 21 other divergent results were interpreted as either indeterminate or positive, a common reactivity being exhibited by all 5 assays. The most important discrepancies occurred on 3 HCV-RNA-positive samples which came up negative in some assays: 2 samples with isolated NS3 reactivity were negative by Matrix and Murex Western blot, 1 of them being also negative by Inno-Lia III; another sample was negative by RIBA-3 and Matrix due to weak signals (< 1) on core and NS3 proteins, which did not exceed 1+ with the other assays. CONCLUSIONS: With more uniform criteria for interpretation, the results would have been less divergent. Some assays should improve their sensitivity to the NS3 protein.

[Results of the first 9 months of testing for anti-HIV antibodies in blood donors in France]. / Bilan des 9 premiers mois de dépistage des anticorps anti-HIV chez les donneurs de sang en France.

An inquiry conducted in all the French blood transfusion centres from the 1st of July, 1985 to the 31st of March, 1986 in respect of blood donations confirmed to be positive for anti-HIV antibodies has given the following results: prevalence of 0.59 per thousand (1661/2,809,744); significant difference between first-time and regular blood donors (2.04% and 0.39% respectively); predominance of males (85%); 65% are less than 30 years old; the main risk factors are homosexuality (49%) and the use of I.V. drugs (28%).

[Hepatitis B virus markers and lymphocyte populations in the asymptomatic multiple-drug addict]. / Etude des marqueurs de l'HBV et des populations lymphocytaires chez le polytoxicomane asymptomatique.

The authors have studied in particular hepatitis B virus markers and the ratio of OKT4+/OKT8+ cells in two subgroups of 52 deprived asymptomatic drug addicts. In the group 1 (deprived for 19 days on an average), 52% of the subjects showed a ratio of OKT4+/OKT8+ less than 1, whereas in the group 2 (deprived for 30 months on an average), this percentage is only of 25%. HBV markers were present in 90% of the subjects in each group. We would like to point out the high frequency of the anti-HBc positivity without other markers in these two groups, respectively 20% in the group 1 and 32% in the group 2. These results emphasize the interest in screening systematically this marker in all blood donors.

[Demonstration of Australia antigen in a rheumatologic population]. / Recherche de l'antigène Australia dans une population rhumatologique

The authors looked for Australia antigen in a population of 578 rheumatic patients, 300 of whom were polyarthritic, by electrosyneresis and complement fixation methods. Australia antigen was found in 26 patients, and anti-Australia antibodies in 33 patients. Most of these patients were suffering from rheumatoid polyarthritis--22 presented hepatic disturbance, and 28 had undergone surgical operations, blood transfusions, and repeated hospitalization. The presence of Australia antigen did not in any case appear to play a role in the development of the lesions, apart from the occurrence of signs of hepatic lesions, but appeared to be an indicator of a form of hospitalization.

[Plasma concentrations of LH and of sex steroids during the normal menstrual cycle and during contraceptive treatment]. / Concentrations plasmatiques de LH et des stéroïdes sexuels pendant le cycle menstruel normal et sous thérapeutique contraceptive

The authors have studied the long-term effects of combined oestrogen-progestogen on the secretion of gonadotrophins and on ovarian function. Estimation of the radio-immune levels of the plasma concentrations of the pituitary luteinizing hormone (LH), of oestradiol (E2), of progesterone (P) and of 20 alpha hydroxyprogesterone (20 alpha OHP) and of testosterone (T) served as a base for this study. A test cycle and 8 cycles in which a combination of 50 micrograms of ethinyl-oestradiol and 0.5 mg of norgestrel were administered were studied in 4 normal volunteer women. A pituitary stimulation test using 50 micrograms of gonadotrophin "releasing factor" (LH-RH) was given during the 7th cycle. Ovarian stimulation using human menopausal gonadotrophins (HMG) was given during the 8th cycle of treatment in 3 of the women and in 3 other subjects. Pituitary secretion of LH and ovarian secretion of E2 and P are partially inhibited. Pituitary response to the injection of LH-RH stays normal but 5 out 6 patients had no response to stimulation by gonadotrophins. These results allow us to conclude that the lowering of production of gonadotrophins during treatment with combination oestrogen and progestagens is responsible for inhibition of ovarian activity, and that there is a delay before the latter respond to stimulation by either endogenous or exogenous gonadotrophins.

PIP: Plasma luteinizing hormone (LH), estradiol, progesterone, 20alpha-hydroxyprogesterone, and testosterone were radioimmunoassayed daily throughout a normal menstrual cycle, the 3rd, 6th, and 9th cycles during oral contraception with Stediril, and during stimulation with LH-releasing factor (LH-RF), human menopausal gonadotropin (HMG), and human chorionic gonadotropin (HCG). 6 women aged 23-30 took Stediril (50 mcg ethinyl estradiol and .5 mg norgestrel, combined) for 1 year. I n the control menstrual cycle, LH rose to a plateau in the follicular and luteal phases, and a high midcycle peak; estradiol rose progressively until its midcycle peak, then fell and rose again; testosterone varied with higher peaks at midcycle; progesterone began to rise on the day of the LH peak to a maximum 5-9 days after ovulation; 20alpha-hydroxyprogesterone resembled progesterone but at a lower magnit ude. During pill cycles, the subjects took 1 mg dectancyl every 6 hours starting the day before blood sampling to inhibit adrenal corticosteroids. LH, estradiol, and progesterone were very low and invariant from Days 9 to 18. 50 mcg LH-RH elicited a significant LH peak (90-370 ng/ml) within 15-30 minutes. 75 IU FSH did not stimulate formation of a corpus luteum in 3 subjects taking 4 mg dexamethasone per day, although 150 IU FSH caused a corpus luteum to develop in 1 of 3 not taking the corticosteroid. Thus LH, estradiol, and progesterone secretions were incompletely inhibited by Stediril.