[Pediatric neuroborreliosis : diagnosis and treatment]. / Neuroborréliose chez l'enfant. Diagnostic et prise en charge.

Neuroborreliosis is the second most frequent presentation of Lyme disease in children. Isolated facial palsy is the most classical manifestation of neuroborreliosis, but another clinical picture can be found in children: subacute meningitis, radiculoneuritis, or rarely severe neurological manifestations (transverse myelitis, encephalitis). Diagnosis and treatment guidelines of neuroborreliosis in children will be reviewed here. They are frequently discussed, especially concerning the need for lumbar puncture for diagnosis, and the choice of antibiotic regimen and administration route.

La neuroborréliose est la deuxième présentation la plus fréquente de la maladie de Lyme en pédiatrie. La paralysie faciale isolée en constitue la manifestation la plus classique, mais elle peut également se présenter sous la forme d'un tableau de méningite subaiguë, de radiculonévrite ou, rarement, par des manifestations sévères (encéphalite, myélite). Nous présentons ici les recommandations de diagnostic et de traitement de la neuroborréliose en pédiatrie. Celles-ci font l'objet de discussions fréquentes, notamment concernant la place de la ponction lombaire pour le diagnostic et le choix de la molécule et de la voie d'administration pour le traitement.Résumé non disponible.

[Acute neonatal osteomyelitis, an incidental life-changing diagnosis]. / Cas clinique. Une ostéomyélite aiguë néonatale, un diagnostic parfois fortuit qui peut changer une vie.

Acute neonatal osteomyelitis is a challenging disease and its diagnostic is important to avoid comorbidities. Staphylococcus aureus is the most often involved germ. The diagnostic challenge lies in its pauci-symptomatology in the premature infant in contrast to a more obvious clinical presentation in the term infant or child. The risk factors inherent to prematurity are invasive monitoring, repeated blood sampling, prolonged central catheterization, immature immune response and length of hospital stay. We report the case of an osteomyelitis secondary to staphylococcal sepsis in a preterm infant born at 25 weeks and 3 days of gestational age. The diagnosis was made incidentally on an abdominal x-ray. The low parental compliance for the child's follow-up does not allow us to affirm a future without sequelae even if the elements at our disposal at 8 months suggest a favorable outcome. Acute neonatal osteomyelitis remains a difficult but crucial diagnosis for the future development of the child.

L'ostéomyélite aiguë néonatale est un diagnostic rare, mais qui doit être posé pour en diminuer les comorbidités. Le staphylocoque doré est le germe le plus souvent en cause. La difficulté diagnostique réside dans sa pauci-symptomatologie, en particulier chez le prématuré. La voie de contamination la plus fréquente est hématogène. Les facteurs de risque inhérents à la prématurité sont le monitoring invasif, les prélèvements à répétition, le cathétérisme central prolongé, une réponse immunitaire immature et la durée d'hospitalisation. Nous rapportons le cas d'une ostéomyélite secondaire à un sepsis à staphylocoque doré chez un prématuré né à 25 semaines et 3 jours d'aménorrhée. Le diagnostic a été réalisé fortuitement sur une radiographie d'abdomen à blanc. La faible compliance parentale pour le suivi de l'enfant ne nous permet pas d'affirmer un futur sans séquelle, même si les éléments à notre disposition lors d'une consultation à 8 mois laissent penser une évolution favorable. L'ostéomyélite aiguë néonatale est un diagnostic difficile à poser, mais crucial pour le développement futur de l'enfant.

Association of Anti-glycan Antibodies and Inflammatory Bowel Disease Course.

BACKGROUND AND AIMS: The usefulness of anti-glycan antibodies alone or combined with anti-Saccharomyces cerevisiae [ASCA] or perinuclear antineutrophil cytoplasmic [pANCA] antibodies for diagnosis of inflammatory bowel disease [IBD], differentiation between Crohn's disease [CD] and ulcerative colitis [UC], disease stratification including IBD phenotype, and also for determination of the course of the disease, remain unclear. METHODS: A large panel of serological anti-glycan carbohydrate antibodies, including anti-mannobioside IgG antibodies [AMCA], anti-chitobioside IgA [ACCA], anti-laminaribioside IgG antibodies [ALCA], anti-laminarin [anti-L] and anti-chitine [anti-C] were measured in the serum from a cohort of 195 patients with IBD] [107 CD and 88 UC]. The respective accuracy of isolated or combined markers for diagnosis, disease differentiation, stratification disease phenotype, and severity of the disease course, defined by a wide panel of criteria obtained from the past medical history, was assessed. RESULTS: The positivity of at least one anti-glycan antibody was detected in a significant higher proportion of CD and UC compared with healthy controls [p < 0.0001 and p < 0.0007, respectively]. Whereas ASCA and ANCA antibody status had the highest efficacy to be associated with CD in comparison with UC (area under receiver operating characteristic curve [AUROC] = 0.70 for each], the adjunction of anti-laminarin antibody substantially improved the differentiation between CD and UC [AUROC = 0.77]. Titres of ACCA [> 51U/ml] and anti-laminarin [> 31U/ml] were significantly linked with a higher association with steroid dependency (odds ratio [OR] =2.0 [1.0-4.0], p = 0.03 and OR = 2.4 [1.1-5.2], p = 0.02, respectively]. We further defined the respective performance of anti-glycan antibodies to discriminate between patients with severe or not severe CD and UC course and determined the associated optimal cut-off values: severe CD course was significantly more likely in case of AMCA > 77U/ml [OR = 4.3; p = 0.002], ASCA > 63U/ml [OR = 3.5; p < 0.009] and at a lesser degree ACCA > 50U/ml [OR = 2.8; p < 0.02] and severe UC course was significantly associated with AMCA > 52U/ml [OR = 3.4; p = 0.04] and ACCA > 25U/ml [OR = 3.0; p < 0.04]. CONCLUSIONS: Anti-glycan antibodies are valuable serological markers, especially AMCA antibodies that may help clinicians to promptly classify patients into high risk for severe disease.

Systematic review: new serological markers (anti-glycan, anti-GP2, anti-GM-CSF Ab) in the prediction of IBD patient outcomes.

Traditionally, IBD diagnosis is based on clinical, radiological, endoscopic, and histological criteria. Biomarkers are needed in cases of uncertain diagnosis, or to predict disease course and therapeutic response. No guideline recommends the detection of antibodies (including ASCA and ANCA) for diagnosis or prognosis of IBD to date. However, many recent data suggest the potential role of new serological markers (anti-glycan (ACCA, ALCA, AMCA, anti-L and anti-C), anti-GP2 and anti-GM-CSF Ab). This review focuses on clinical utility of these new serological markers in diagnosis, prognosis and therapeutic monitoring of IBD. Literature review of anti-glycan, anti-GP2 and anti-GM-CSF Ab and their impact on diagnosis, prognosis and prediction of therapeutic response was performed in PubMed/MEDLINE up to June 2014. Anti-glycan, anti-GP2 and anti-GM-CSF Ab are especially associated with CD and seem to be correlated with complicated disease phenotypes even if results differ between studies. Although anti-glycan Ab and anti-GP2 Ab have low sensitivity in diagnosis of IBD, they could identify a small number of CD patients not detected by other tests such as ASCA. Anti-glycan Abs are associated with a progression to a more severe disease course and a higher risk for IBD-related surgery. Anti-GP2 Ab could particularly contribute to better stratify cases of pouchitis. Anti-GM-CSF Ab seems to be correlated with disease activity and could help predict relapses. These new promising biomarkers could particularly be useful in stratification of patients according to disease phenotype and risk of complications. They could be a valuable aid in prediction of disease course and therapeutic response but more prospective studies are needed.

Development of an algorithm incorporating pharmacokinetics of adalimumab in inflammatory bowel diseases.

OBJECTIVES: Several decision algorithms based on the measurement of infliximab (IFX) trough levels and antibodies to IFX have been proposed. Whether such algorithms can be extrapolated to the pharmacokinetics of adalimumab (ADA) has yet to be determined. METHODS: A prospective study included all consecutive patients with inflammatory bowel disease (IBD) having a disease flare while being on ADA 40 mg every 2 weeks were included. All patients were primary responders to ADA therapy and were anti-tumor necrosis factor (TNF) naive. ADA trough levels and antibodies against ADA (AAA) were measured blinded to clinical data (Elisa LISA-Tracker, Theradiag). All patients were optimized with ADA 40 mg weekly. Four months later, in the absence of clinical remission (CR; Crohn's disease activity index <150 for Crohn's disease (CD), and Mayo score <2 for ulcerative colitis), patients were treated with IFX therapy. Patients were divided into three groups based on ADA trough levels and based on previous studies: group A, ADA>4.9 µg/ml; group B, ADA<4.9 µg/ml and undetectable levels of AAA (<10 ng/ml); and group C, ADA<4.9 µg/ml and AAA >10 ng/ml. RESULTS: A total of 82 patients were included (55% CD; mean age=43 years, disease duration=7.4 years, duration of ADA therapy=17 months). After optimization of ADA treatment, 29.2% of patients achieved CR in group A (N=41), 67% in group B (N=24), and 12% in group C (N=17; P<0.01 between groups A/B and B/C). C-reactive protein level at the time of relapse, disease duration, duration of ADA therapy, and IBD type was not predictive of CR after ADA optimization by univariate analysis. The response to ADA optimization was significantly more durable in group B (15 months) than in groups A and C (4 and 5 months, respectively). Fifty-two patients who failed following ADA optimization (63%) were treated with IFX, and 30.6% of them achieved CR. CR rates following IFX initiation were 6.9%, 25%, and 80% in groups A, B, and C, respectively (P<0.01 between groups C/A and between groups C/B). Duration of response to IFX was significantly higher in group C than in groups A and B (14 vs. 3 and 5 months, respectively, P<0.01). CONCLUSIONS: The presence of low ADA trough levels without AAA is strongly predictive of clinical response in 67% of cases after ADA optimization. Conversely, low ADA levels with detectable AAA are associated with ADA failure, and switching to IFX should be considered. ADA trough levels >4.9 µg/ml are associated with failure of two anti-TNF agents (ADA and IFX) in 90% of cases, and switching to another drug class should be considered.

Review article: biosimilars are the next generation of drugs for liver and gastrointestinal diseases.

BACKGROUND: A biosimilar is a copy version of an approved original biological medicine whose data protection has expired. AIM: To provide an overview of the development of biosimilars worldwide. METHODS: Literature review of manufacturing processes of biosimilars, differences and similarities between biosimilars and the reference product, approval pathways for biosimilars, challenges in clinical trial study design and available data from clinical trials. RESULTS: Biosimilars have the same amino acid sequence and highly similar glycosylation patterns that overlap with the originator product. Both efficacy and toxicity are difficult to predict due to subtle molecular changes that might have profound effects on clinical efficacy, safety and immunogenicity. Their main advantage is related to cost savings. Direct evidence of safety and benefit from clinical trials, post-marketing pharmacoviligance and unequivocal identification of the product as a biosimilar are requirements before approval. Non-inferiority or equivalence trials are required by regulatory agencies. Over the past years, several biosimilars have been approved such as erythropoietin or growth factors. Recently, two monoclonal antibodies, Remsima and Inflectra, have been shown to be equivalent to infliximab (INX) in safety and efficacy in rheumatologic conditions. Interchangeability, automatic substitution and switching are key issues when treating patients with biosimilars in clinical practice. CONCLUSIONS: Biosimilars represent a new generation of drugs in liver and gastrointestinal diseases. On June 27, 2013, Hospira's Inflectra (INX) was the first biosimilar monoclonal antibody to receive positive opinion from European Medicines Agency's Committee for Medicinal Products for Human Use for rheumatoid arthritis, inflammatory bowel disease and plaque psoriasis.

Role of human immunodeficiency virus type 1 envelope structure in the induction of broadly neutralizing antibodies.

Very soon after the discovery of neutralizing antibodies (NAbs) toward human immunodeficiency virus type 1 (HIV-1) infection, it became apparent that characterization of these NAbs would be an important step in finding a cure for or a vaccine to eradicate HIV-1. Since the initial description of broadly cross-clade NAbs naturally produced in HIV-1 patients, numerous studies have described new viral targets for these antibodies. More recently, studies concerning new groups of patients able to control their viremia, such as long-term nonprogressors (LTNPs) or elite controllers, have described the generation of numerous envelope-targeted NAbs. Recent studies have marked a new stage in research on NAbs with the description of antibodies obtained from a worldwide screening of HIV-positive patients. These studies have permitted the discovery of NAb families with great potential for both neutralization and neutralization breadth, such as PG, PGT, CH, and highly active agonistic anti-CD4 binding site antibodies (HAADs), of which VRC01 and its variants are members. These antibodies are able to neutralize more than 80% of circulating strains without any autoreactivity and can be rapidly integrated into clinical trials in order to test their protective potential. In this review, we will focus on new insights into HIV-1 envelope structure and their implications for the generation of potent NAbs.

MN/CA9: a potential gene marker for detection of malignant cells in effusions.

Many cancers cause malignant effusions. The presence of malignant cells in effusions has implications in diagnosis, tumour staging and prognosis. The detection of malignant cells currently presents a challenge for cytopathologists. New adjunctive methods are needed. Although the effusions provide excellent materials for molecular assay, the available molecular markers are extremely limited, which hinders its clinical application. MN/CA9 has proved to be a valuable marker in many cancers such as lung, breast, colon, kidney, etc. The present study was to evaluate MN/CA9 as a new molecular marker for the detection of cancer cells in pleural effusions. Seventy-one pleural effusions including 59 malignant effusions from patients with cancer, and 12 patients with benign diseases as a control, were subjected to RT-PCR for detection of MN/CA9 gene expression. MN/CA9 gene expression was detected in 53/59 (89.8%) pleural effusions from cancer patients (15/16 for breast cancers, 10/11 for lung cancers, 4/4 for ovary cancers, 2/3 for colon-rectal cancers, 5/6 for cancers of unknown site, 7/8 for mesothelioma and 10/11 for other cancers). Furthermore, MN/CA9 was positive in 13/18 (72.2%) of cytologically negative effusions of cancer patients. MN/CA9 was detected in only 1/12 (8.3%) effusions from the control patients (p < 0.01). The sensitivity and specificity of MN/CA9 gene expression were, respectively, 89.8% and 91.7%. Our preliminary results suggest that MN/CA9 could be a potential marker for the detection of malignant cells in effusions. A large-scale study is needed to confirm these results.

S100A1: a powerful marker to differentiate chromophobe renal cell carcinoma from renal oncocytoma.

AIMS: The common subtypes of renal tumours are conventional, papillary, chromophobe carcinoma and oncocytoma. The morphological differentiation between chromophobe carcinoma and oncocytoma may be difficult. The aim was to evaluate S100A1 as a new marker for the differentiation of the two subtypes. METHODS AND RESULTS: Thirty-nine tumour samples [nine clear cell renal cell carcinomas (RCCs), six papillary RCCs, nine chromophobe RCCs and 15 oncocytomas] were studied. The protein expression of S100A1 was evaluated by immunohistochemistry. The gene expression of S100A1 was analysed by reverse transcriptase-polymerase chain reaction. Nine oncocytomas showed strong immunoreactivity for S100A1. Four oncocytomas were scored as moderate and one as weak reactivity. In total, 14/15 (93%) of oncocytomas were considered to be immunopositive. In contrast, all nine chromophobe RCCs were considered to be immunonegative. There was a significant difference in the positive percentages of staining of S100A1 between these two subtypes (P < 0.01). S100A1 immunoreactivity was observed in 6/9 clear cell and 4/6 papillary carcinomas. The results of S100A1 gene expression corresponded well with the results of immunohistochemistry. CONCLUSION: S100A1 may be a potentially powerful marker to differentiate the chromophobe RCC from renal oncocytoma.

Microsatellite profile in hormonal receptor genes associated with breast cancer.

Given that breast cancer is depending on multiple hormonal influences, the nuclear receptors, estrogen receptor alpha, estrogen receptor beta and androgen receptor, are candidates for cancer susceptibility markers. We conducted an association study in a case-control population (139 cases and 145 controls) by genotyping three potentially functional microsatellites (TA)n, (CA)n and (CAG)n in the ERa, ERb and AR genes respectively. For (CAG)n polymorphism, a significant difference was observed using a cut-off 15 repeats CAG between genotypes short-short/short-long/long-long in cases and control subjects (p = 0.009) and also between the distribution of short/long allele in the two groups of individuals (p = 0.001). Genotypes comprising one or two short (CAG)n sequences had higher risk of breast cancer compared to genotypes with two long allele (odds ratio = 1,93; confidence interval = 1.05-3.55; p = 0.03). No significant difference was observed in allele frequency or in short/long allele percentage for (CA)n or (TA)n polymorphism (cut-off 22 CA and 19 TA repeats), neither in genotype frequencies (short-short, short-long or long-long). When the three microsatellite genotype were taken in analysis, the profile short CA-long TA-short CAG could clearly discriminate between cases and controls (p = 0.006). Also, this combined genotype profile has greater predictive values for breast cancer than (CAG)n genotype alone (predictive positive value 57,1% versus 53,7% and predictive negative value 53% versus 23% respectively). Our results sustain a polygenic model of breast cancer with gene-gene interactions; combined effects of three low-risk polymorphisms conferred significant genetic predisposition. Genotyping hormonal receptor genes ERa, ERb and AR could be a useful genetic marker for defining disease risk.

S100A1 and KIT gene expressions in common subtypes of renal tumours.

AIM: The aim of this study is to evaluate the S100A1 and KIT as gene markers for the differentiation of common subtypes of renal tumours. METHODS: Fifty-five tissue samples (15 clear cell RCCs, 15 papillary RCCs, 7 chromophobe RCCs, 8 oncocytomas and 10 normal renal tissues) were studied The gene expressions of S100A1 and KIT were analysed by one-step RT-PCR by using the specific primers. RESULTS: S100A1 was expressed in 2/15 clear cell RCCs, 11/15 papillary RCCs, 7/8 oncocytomas and in 0/7 chromophobe RCCs. KIT gene was expressed in 6/7 chromophobe RCCs and 7/8 oncocytomas while 0/15 clear cell RCCs and 1/15 papillary RCCs expressed kit gene. Normal tissue expressed neither S100A1 nor KIT gene. CONCLUSION: S100A1 and KIT can be used as gene markers for the differentiation of common subtypes of renal tumours.

Differential downstream effects of CD40 ligation mediated by membrane or soluble CD40L and agonistic Ab: a study on purified human B cells.

With the addition of various cytokines, the CD40-CD40 ligand (CD40L) system can act as a T-helper cell surrogate to permit B lymphocytes to produce large amounts of polyclonal Ig. In the present study, we tested six CD40-CD40L stimulation models: (i, ii) soluble agonistic 89 and G28.5 mAbs ; (iii, iv) 89 and G28.5 bound via their Fc fragments on CDw32-transfected mouse fibroblasts; (v) purified, soluble, trimeric human CD40L molecules (sCD40L); and (vi) human CD40L expressed by a CD40L-transfected mouse fibroblastic cell line (LCD40L). Target B cells consisted of purified blood and tonsillar CD19+ lymphocytes cultured in the presence of CD40 stimuli and IL-2 and IL-10, added at the onset of each B cell culture. A) There was differential expression of CD69, CD80 and CD86 exposure to sCD40L and LCD40L was ensued by the strongest % MFI changes over control. B) In blood B cells, mAbs and sCD40L induced IgA, IgM and IgG production almost equally well; LCD40L proved less efficient. In contrast, in tonsil B cells, LCD40L induced significantly more IgA, IgG1, IgG3 and IgM production than other signals. Using certain CD40/CD40L stimuli to model in vitro Ig production, a system used regularly in many laboratories, may affect the interpretation based on the cell type and on the CD40/CD40L system used.

In vitro reconstructed mucosa-integrating Langerhans' cells.

All three-dimensional in vitro mucosal models constructed, thus far, have only been reconstituted by epithelial cells. We have developed a reconstructed oral and vaginal epithelium that integrates Langerhans' cells (LC), the dendritic cells (DC) of malpighian epithelia. The epithelium was composed of gingival or vaginal keratinocytes seeded on a de-epidermized dermis (DED) and grown in submerged culture for 2 weeks. LC precursors, obtained after differentiation of cord blood-derived CD34+ hematopoietic progenitor cells (CD34+HPC) by granulocyte macrophage-colony stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and Flt3-ligand (Flt3-L), were introduced after 6-8 days of culture into the reconstituted epithelium. The in vitro reconstituted mucosal epithelium formed a multilayered, well-differentiated epithelial structure, confirmed by the immunohistochemical expression of cytokeratins 4, 6, 10, 13, 14, 16 and involucrin. LC were identified in the basal and suprabasal epithelial layers by CD1a antigen, S100 protein and Langerin/CD207 expression, and by transmission electron microscopy. Type IV collagen was expressed at the chorio-epithelial junction, and most ultrastructural features of this junction were visualized by electron microscopy. This in vitro reconstructed gingiva or vagina integrating LC represents interesting models very similar to native tissues. Because LC play an important role in the mucosal immune system, our models could be useful for conducting studies on interactions with pathogenic agents (viruses, bacteria etc.), as well as in pharmacological, toxicological and clinical research.

HIV-gp160 modulates differentially the production in vitro of IgG, IgA and cytokines by blood and tonsil B lymphocytes from HIV-negative individuals.

HIV1-gp160 holds promises in anti-HIV vaccinal strategies. However, this molecule has been described to exhibit superantigenic activities. The present study aimed at examining the effect(s) of HIV1-gp160 on human B cells and in particular on B cells originating from HIV- donors. We purified human B cells of various origins, i.e. from blood and from tonsils (representing a mucosal-type origin), and we tested these cells (stimulated with a polyclonal B cell activator, interleukin (IL)-2 and IL-10 as cytokines, and recombinant HIV1-gp160) for the production of IgG and IgA in an in vitro model. Gp160 induced significantly less total IgG by blood - but not tonsil-originating - B cells and did not affect total IgA production. Further, HIV1-gp160 up-regulated IL-2-, IL-4- and IL-10-mRNA levels in stimulated blood B cells (these cytokines are known to be active on B cell activation and differentiation). Interestingly, HIV1-gp160 also up-regulated IL-1beta-, transforming growth factor (TGF)-beta-, interferon (IFN)-gamma- and IL-12-mRNA levels in stimulated mucosal-type, tonsil-originating, B cells. As these latter cytokines are involved in proinflammatory activities, HIV-gp160 delivery at the mucosal sites would be compatible with an adjuvant activity.

Flow cytometry versus histamine release analysis of in vitro basophil degranulation in allergy to Hymenoptera venom.

BACKGROUND: Flow cytometry (FCM) has been proposed for specific allergy in vitro testing. We investigated its biological significance for allergy to Hymenoptera venoms and compared it with the routinely performed basophil histamine release test (HRT). METHODS: Blood samples from 26 allergic and 8 nonallergic donors were incubated with venom at serial concentrations. Basophils were analyzed with anti-CD45-PE-Cyanin 5, Anti-IgE-FITC, and Anti-CD63-Phycoerythrine. HRT was measured by radioimmunoassay. RESULTS: FCM was as convenient as HRT for measuring basophil reactivity in at least 87% of allergic and 75% of nonallergic subjects. CD63 outer expression was specifically induced in 91% of releaser subjects (86% on HRT) and in 1 of 10 tests in nonallergic donors, or one of six tests (16% on HRT) in allergic patients tested with an irrelevant allergen. Both methods were concordant in 85.7% of the tests. The three discordant patients had low-grade reactions and borderline biological responses on FCM (n = 2) or HRT (n = 1). CONCLUSIONS: The dynamic, physiologic significance of CD63, the dose-response curve, and dependency on ethylene-diaminetetra acetic acid suggested that both tests reflect the same mechanism.

Experimental model of congenital toxoplasmosis in guinea-pigs: use of quantitative and qualitative PCR for the study of maternofetal transmission.

Maternofetal transmission of Toxoplasma gondii was assessed in pregnant guinea-pigs, with a gestational period of 65 +/- 5 days. A total of 56 female guinea pigs was infected by the intraperitoneal route (RH strain), by the oral or the intraperitoneal route (Prugniaud strain; PRU) or by the oral route (76K strain). Inoculation was performed 90 +/- 18 days or 30 +/- 9 days before the onset of gestation or 20 +/- 6 days or 40 +/- 6 days after. Gestational age was determined by a progesterone assay. Parasite loads (fetal brain and liver) were assessed by nested PCR and real-time PCR quantification on Light Cycler was performed with a SYBR Green I technique. The 76K strain appeared to be the most virulent in the model: the neonatal survival rate was 31%, in contrast to 53% and 68% for the PRU and RH strains, respectively. The percentage of survival of neonates for all strains taken together was lower after inoculation at 40 days' gestation (25%) than at 20 days' gestation (77%). Whatever the strain, maternofetal transmission determination was greater with nested PCR (54% for RH, 84% for PRU and 86% for 76K strains) than with real-time quantitative PCR (31% for RH, 66% for PRU and 76% for 76K strains). However, real-time quantitative PCR showed that neonatal parasite load was greater with the cystogenic strains (76K, PRU) and that high hepatic load (> 10000 parasites/g) was often associated with disease severity (11 of 12 cases). Therefore, this technique may provide an important element in understanding this congenital disease.

Detection of GB virus C/hepatitis G virus in semen and saliva of HIV type-1 infected men.

OBJECTIVE: To investigate the presence of the genome of GB virus C/hepatitis G virus (GBV-C/HGV) in semen and saliva from HIV-1-infected men. METHODS: Samples of blood from 33 men seropositive for HIV-1 were tested for the presence of GBV-C/HGV markers of infection, RNA by RT-PCR, and anti-E2 antibodies by ELISA, respectively. The cell-free fractions of seminal fluid and saliva samples of the patients with positive blood samples for GBV-C/HGV RNA or anti-E2 antibodies were then analyzed for the presence of the RNA of this virus. In addition, six semen samples and 11 saliva samples from GBV-C/HGV-negative men were tested. RESULTS: The GBV-C/HGV RNA tested by RT-PCR was recovered from blood in 11 patients of 33 (33.3%), and the antibodies to E2 envelope protein were detected in six patients (18.2%). Since no patient was positive for both markers, the overall prevalence of GBV-C/HGV infection was 51.5% in the studied population. Four-all belonging to the homosexual risk group-of the 17 men with markers to GBV-C/HGV in blood were found to be positive for GBV-C/HGV RNA in mucosal samples: two of them exhibited genomic RNA in both semen and saliva, and two others were positive for semen only. The absence of inhibitors of the PCR technique was confirmed in all mucosal fractions found negative for GBV-C/HGV RNA, except for one saliva sample and one seminal fluid sample. CONCLUSION: These results confirm the high prevalence of GBV-C/HGV infection in patients infected with HIV-1 by sexual exposure and the presence of GBV-C/HGV RNA in seminal fluid and saliva of men with markers of this virus in the blood, suggesting that mucosal fluids could be a potential source for the spread of the GBV-C/HGV infection.

Functional HIV CXCR4 coreceptor on human epithelial Langerhans cells and infection by HIV strain X4.

HIV can cross the intact epithelium of genital mucosae via Langerhans cells. Fresh Langerhans cells are known to express CD4 and CCR5. The presence of CXCR4 on the surface of cultured but not freshly isolated Langerhans cells has been described. In the present study, we demonstrate that CXCR4 was expressed by fresh Langerhans cells isolated and purified from epidermis. However, the percentage of Langerhans cells expressing CXCR4 or CCR5 increased during maturation of the cells in culture, especially in the presence of exogenous granulocyte-macrophage colony-stimulating factor. To determine whether CXCR4 was functional, freshly isolated Langerhans cells were infected with HIV LAI, a T-cell-tropic strain, and p24 protein production was measured in culture supernatants. p24 production was observed when infected Langerhans cells were cocultured with SupT1 cells. However, the presence of HIV provirus DNA was evidenced within the infected Langerhans cells by nested PCR. Ultrastructural studies confirmed the formation of syncytia when Langerhans cells were cocultured with SupT1 cells. Preincubation of Langerhans cells with azidothymidine or SDF-1-alpha, a natural ligand for CXCR4, prevented infection. These data demonstrated that CXCR4 is present on the surface of Langerhans cells freshly isolated from human skin epidermis and that this expression is functional.

The expression of G250/mn/CA9 antigen by flow cytometry: its possible implication for detection of micrometastatic renal cancer cells.

Monoclonal antibody (mAb) G250 is a well characterized and specific mAb to renal cell carcinoma (RCC). The gene G250 was recently cloned and was proved to be homologous to MN/CA9. The G250/MN/CA9 antigen was recently explored as a potential marker for RCC. Flow cytometry (FCM) allows quantitative analysis of cells. The present study describes a flow cytometric method to detect this antigen in human cell lines and in malignant and normal renal tissues. Twelve human carcinoma cell lines (HeLa, Colo205, HT29, BxPC3, OVCAR3, SKOV3, ACHN, A704, CAKI-2, SKRC-59, SKRC-10, and SKRC-52), 10 specimens of normal peripheral blood mononuclear cells, and 38 malignant and 36 adjacent normal renal tissues were studied. The malignant and normal renal tissues were disaggregated mechanically into a single-cell suspension, stained by mAb G250, and analyzed by FCM. All 22 of the clear cell carcinomas, 6 of 8 mixed cell carcinomas, and 3 of 6 granular cell carcinomas were positive for G250/MN/CA9 antigen. SKRC-52 and SKRC-10 were strongly positive for G250/ MN/CA9. The G250/MN/CA9 antigen could also be detected in HeLa, SKOV3, HT29, and A704 cells. One chromophobic, one chromophilic cell carcinoma, the normal renal tissues, and normal peripheral blood mononuclear cells were considered as negative. Our results further confirmed that the G250/MN/CA9 antigen was an ideal marker for RCC, especially for clear cell carcinomas, and that this antigen was present in several types of malignant cells. FCM may serve as a fast tool of immunocytochemical detection of renal cancer cells. Flow cytometric detection of renal cancer cells by using mAb G250 should be further explored.