Functional Exhaustion Limits CD4+ and CD8+ T-Cell Responses to Congenital Cytomegalovirus Infection.

BACKGROUND: Cytomegalovirus (CMV) infection during fetal life causes severe symptoms and is associated with prolonged viral excretion. Previous studies reported low CD4(+) T-cell responses to CMV infection in early life, contrasting with large responses of effector CD8(+) T cells. The mechanisms underlying the defective CD4(+) T-cell responses and the possible dissociation with CD8(+) T-cell responses have not been clarified. METHODS: The magnitude and the quality of the fetal CD8(+) and CD4(+) T-cell responses to CMV infection were compared to those of adults with primary or chronic infection. RESULTS: In utero CMV infection induced oligoclonal expansions of fetal CD4(+) and CD8(+) T lymphocytes expressing a T-helper type 1 or Tc1 effector phenotype similar to that of adult CMV-specific cells. However, the effector cytokine responses and the polyfunctionality of newborn CD4(+) and CD8(+) T cells were markedly lower than those of adult cells. This reduced functionality was associated with a higher expression of the programmed death 1 inhibitory receptor, and blockade of this receptor increased newborn T-cell responses. CONCLUSIONS: Functional exhaustion limits effector CD4(+) and CD8(+) T-lymphocyte responses to CMV during fetal life.

Primary human cytomegalovirus infection induces the expansion of virus-specific activated and atypical memory B cells.

BACKGROUND: Although neutralizing antibodies play a central role in the control of cytomegalovirus (CMV) dissemination, little is known about the response of B lymphocytes to primary human CMV infection. METHODS: The proportion, phenotype, specificity, and functionality of B-cell subsets were studied in a cohort of pregnant women with primary CMV infection. CMV-seronegative pregnant women, as well as CMV-seronegative and CMV-seropositive healthy adults, were included as controls. RESULTS: Primary CMV infection was associated with a sustained expansion of activated (CD27(+)CD20(+)CD21(low)) and atypical (CD27(-)CD20(+)CD21(low)) memory B cells (MBCs). Both subsets expressed an effector phenotype, and their proportions were correlated with viremia. Activated MBCs expressed high levels of activation markers and included high frequencies of tumor necrosis α (TNF-α)-producing cells, whereas atypical MBCs expressed high levels of inhibitory receptors and had low TNF-α responses. Fluorescent-labeled antigen experiments indicated that activated and atypical MBCs were enriched in CMV-specific cells. CONCLUSIONS: Primary CMV infection mobilizes a large pool of memory B cells that includes activated and atypical MBCs. The functional regulation of CMV-specific MBCs may limit the production of antibodies and the control of viral dissemination.

Functional exhaustion of CD4+ T lymphocytes during primary cytomegalovirus infection.

Human CMV establishes lifelong persistence after primary infection. Chronic CMV infection is associated with intermittent viral reactivation inducing high frequencies of CD4+ T lymphocytes with potent antiviral and helper properties. Primary CMV infection is characterized by an intense viral replication lasting for several months. The impact of this prolonged exposure to high Ag loads on the functionality of CD4+ T cells remains incompletely understood. In pregnant women with primary CMV infection, we observed that CMV-specific CD4+ T lymphocytes had a decreased capacity to proliferate and to produce IL-2. A very large proportion of CMV-specific CD4+ T cells had downregulated the expression of CD28, a costimulatory molecule centrally involved in the production of IL-2. Unexpectedly, both CD28+ and CD28+ CD4+ T cells produced low levels of IL-2. This defective production of IL-2 was part of a larger downregulation of cytokine production. Indeed, CMV-specific CD4+ T cells produced lower amounts of IFN-γ and TNF-α and showed lower functional avidity during primary as compared with chronic infection. Increased programmed death-1 expression was observed in CD28+ CMV-specific CD4+ T cells, and programmed death-1 inhibition increased proliferative responses. These results indicate that primary CMV infection is associated with the exhaustion of CMV-specific CD4+ T cells displaying low functional avidity for viral Ags.

Human cytomegalovirus elicits fetal gammadelta T cell responses in utero.

The fetus and infant are highly susceptible to viral infections. Several viruses, including human cytomegalovirus (CMV), cause more severe disease in early life compared with later life. It is generally accepted that this is a result of the immaturity of the immune system. gammadelta T cells are unconventional T cells that can react rapidly upon activation and show major histocompatibility complex-unrestricted activity. We show that upon CMV infection in utero, fetal gammadelta T cells expand and become differentiated. The expansion was restricted to Vgamma9-negative gammadelta T cells, irrespective of their Vdelta chain expression. Differentiated gammadelta T cells expressed high levels of IFN-gamma, transcription factors T-bet and eomes, natural killer receptors, and cytotoxic mediators. CMV infection induced a striking enrichment of a public Vgamma8Vdelta1-TCR, containing the germline-encoded complementary-determining-region-3 (CDR3) delta1-CALGELGDDKLIF/CDR3gamma8-CATWDTTGWFKIF. Public Vgamma8Vdelta1-TCR-expressing cell clones produced IFN-gamma upon coincubation with CMV-infected target cells in a TCR/CD3-dependent manner and showed antiviral activity. Differentiated gammadelta T cells and public Vgamma8Vdelta1-TCR were detected as early as after 21 wk of gestation. Our results indicate that functional fetal gammadelta T cell responses can be generated during development in utero and suggest that this T cell subset could participate in antiviral defense in early life.

Human cytomegalovirus seroprevalence and risk of seroconversion in a fertility clinic population.

OBJECTIVE: To retrospectively evaluate factors influencing human cytomegalovirus serologic status of couples consulting our fertility clinic. METHODS: Human cytomegalovirus individual serologic status of 3,227 women and 2,565 men was studied according to age, serologic status of the sexual partner, and presence of children in the family at entry in the clinic. Among 1,906 initially seronegative individuals, human cytomegalovirus seroconversions during follow-up were recorded and correlated to age, serologic status of the sexual partner, and presence of children aged younger than 3 years in the family. RESULTS: Human cytomegalovirus status at entry in the fertility clinic depended on age, but women were more frequently seropositive (54%) than men (43%), although they were younger (mean age 33 years for women and 37 years for men). The probability of seroconversion of women and men was significantly associated with the presence of children aged younger than 3 years; 35 of 217 women (16%) and 17 of 130 men (13%) living with children aged younger than 3 years seroconverted compared with 37 of 1,066 women (3.4%) and 16 of 493 men (3.2%) without children. Moreover, women's seroconversion was significantly associated with the seropositivity of the sex partner; 13 of 96 (13.5%) women with a cytomegalovirus seropositive partner seroconverted compared with 33 of 452 (7.3%) of those without such a partner. CONCLUSION: Our results suggest that human cytomegalovirus is sexually transmitted among couples in our fertility clinic. Safe sex practices should be included in hygiene precaution advice given to pregnant women to avoid human cytomegalovirus contamination. LEVEL OF EVIDENCE: II.

Development and evaluation of single sperm washing for risk reduction in artificial reproductive technology (ART) for extreme oligospermic HIV positive patients.

The serodiscordant couples, where the male is HIV-positive, are treated in fertility clinics, using the sperm washing technique by gradient centrifugation. This protocol cannot be carried out in oligo-azoospermic patients, where spermatozoa retrieval from the epididymis and testis must be performed. We developed a single sperm washing technique, where the spermatozoa, after the retrieval, are washed with the aid of a micromanipulator, to obtain virus decontamination and then used for the intracytoplasmic sperm injection (ICSI). The experiment was performed by using sperm samples containing three different viral loads. After one hour of incubation, spermatozoa were taken one by one from the HIV loaded drop and washed in four different microdrops. Before each passage into the next washing drop, the pipette was emptied in a first waste drop and then loaded with new washing medium from a second separate loading drop. After transferring of 10 spermatozoa in these four successive drops, the washing medium and the virus-loaded drops were tested for the HIV RNA presence by the nested RT-PCR technique. The presence of the virus was detected in the waste drop of all three viral loads. The four washing microdrops were each time negative for the presence of HIV-1 RNA, tested by the nested RT-PCR technique. The results show that by rinsing the spermatozoa four times, we are able to diminish the viral load to an undetectable level. Our data demonstrate that single sperm washing can be performed in the cases of extreme male sterility in HIV-positive men. From now on the couples, where the male is oligoazoospermic and HIV positive, could be included in our ICSI program, respecting the usual viral safety level of the ART techniques for the embryo.

Prevalence and epidemiology of HIV type 1 drug resistance among newly diagnosed therapy-naive patients in Belgium from 2003 to 2006.

This study is the first prospective study to assess the prevalence, epidemiology, and risk factors of HIV-1 drug resistance in newly diagnosed HIV-infected patients in Belgium. In January 2003 it was initiated as part of the pan-European SPREAD program, and continued thereafter for four inclusion rounds until December 2006. Epidemiological, clinical, and behavioral data were collected using a standardized questionnaire and genotypic resistance testing was done on a sample taken within 6 months of diagnosis. Two hundred and eighty-five patients were included. The overall prevalence of transmitted HIV-1 drug resistance in Belgium was 9.5% (27/285, 95% CI: 6.6-13.4). Being infected in Belgium, which largely coincided with harboring a subtype B virus, was found to be significantly associated with transmission of drug resistance. The relatively high rate of baseline resistance might jeopardize the success of first line treatment as more than 1 out of 10 (30/285, 10.5%) viruses did not score as fully susceptible to one of the recommended first-line regimens, i.e., zidovudine, lamivudine, and efavirenz. Our results support the implementation of genotypic resistance testing as a standard of care in all treatment-naive patients in Belgium.

Impaired ovarian stimulation during in vitro fertilization in women who are seropositive for hepatitis C virus and seronegative for human immunodeficiency virus.

OBJECTIVE: To analyze the impact of seropositivity with hepatitis C virus (HCV) on in vitro fertilization (IVF) outcomes. DESIGN: Retrospective, case-controlled study. SETTING: Fertility clinic of academic hospital. PATIENT(S): 42 IVF/intracytoplasmic sperm injection cycles in HCV-seropositive women and 84 matched control cycles. INTERVENTION(S): IVF/intracytoplasmic sperm injection treatment for infertility. MAIN OUTCOME MEASURE(S): Ovarian response to stimulation, laboratory findings, and implantation and pregnancy rates. RESULT(S): Absence of ovarian response was statistically significantly higher for HCV-seropositive women compared with controls (10/42 vs 5/84 cycles, respectively). For cycles with oocyte retrieval, HCV-seropositive women required more gonadotropin units compared with controls. The maximum estradiol levels and number of collected oocytes were similar, but HCV-seropositive women had statistically significantly fewer embryos available compared with controls. Embryo morphologic features, number of transferred embryos, and rates of implantation and pregnancy were similar for HCV-seropositive women and controls. CONCLUSION(S): When compared with matched uninfected controls, HCV-seropositive women display a decreased ovarian response.

Development and evaluation of a qualitative reverse-transcriptase nested polymerase chain reaction protocol for same-day viral validation of human immunodeficiency virus type 1 ribonucleic acid in processed semen.

OBJECTIVE: To develop a method for same-day validation of processed semen in the setting of assisted reproductive techniques (ART) with patients who are seropositive for human immunodeficiency virus, type 1 (HIV-1). DESIGN: Laboratory experiments. SETTING: University hospital. PATIENT(S): Volunteers who are HIV-1 seronegative and seropositive. INTERVENTION(S): Evaluation of the sensitivity of a reverse-transcriptase (RT)-nested polymerase chain reaction (PCR) in HIV-1 RNA-positive blood plasma, in artificially infected blood plasma and semen, and in 85 semen samples of 29 HIV-1-seropositive volunteers. Semen was submitted to gradient separation, followed by swim-up. MAIN OUTCOME MEASURE(S): Qualitative detection of HIV-1 RNA in blood plasma and in different parts of semen preparation by using RT-nested PCR, PCR inhibition control by dilution of samples, and an internal control. RESULT(S): The detection limit of our PCR was 20 HIV-1 RNA copies per milliliter. Among seropositive patients, RNA was detected in 25% of fresh semen, 36.5% of seminal plasma, 27.5% of gradient supernatants, and 7.1% of final preparations before the migration-sedimentation stage. Positive final preparations were observed in patients who had blood viral loads of >/=20,000 HIV-1 RNA copies per milliliter. Inhibition was present in 17.6% of seminal plasma and in 20% gradient supernatants and in 2 final preparations among 69 tested. Among 25 preparations tested after the migration-sedimentation stage, 2 were positive (1 patient; 70,000 HIV-1 RNA copies per milliliter). CONCLUSION(S): The RT-nested PCR detects low viral load and allows the validation of semen preparations of HIV-1-seropositive patients for ART on the day of sampling. For this purpose, the validation is performed on spermatozoa that are obtained after gradient separation before swim-up. Inhibition of the PCR must be controlled by using an internal control that is well-designed to explore the detection limit of the method.

Laboratory safety during assisted reproduction in patients with blood-borne viruses.

For couples where one or both partners are infected with human immunodeficiency virus or hepatitis C, the doors to receiving fertility care are opening as a result of better antiviral medication, better long-term prognosis and consequent changes in attitude. In line with this, fertility centres electing to treat couples with blood-borne viral (BBV) infection need to re-examine their policies and procedures to ensure the safety of their staff and both non-infected and infected patients during assisted reproduction treatments. At a time when the European Tissue Directive aims to introduce quality standards for assisted reproduction throughout Europe, we highlight the risks involved when treating patients with known BBV infections and argue that safety cannot be met with any certainty unless samples from such patients are handled within a separate high security laboratory or laboratory area, technically adapted to ensure minimal cross-contamination risk to uninfected gametes and embryos.

Quantitative TaqMan PCR for detection of Pneumocystis jiroveci.

We developed a quantitative real-time PCR assay for detection and quantification of Pneumocystis jiroveci in bronchoalveolar lavage (BAL) specimens based on primers and probe targeting the gene encoding beta-tubulin. The assay was able to detect 50 DNA copies per ml of a standard plasmid containing the target sequence. The intra- and interassay coefficients of variation were 0.46%-4.27% and 0.05-2.00% over 5 log(10) values. Fifty-seven controls of human, viruses, bacteria and fungi DNA samples were amplified and found negative. Fifty-three BAL samples sent to the laboratory for diagnosis of pneumocystosis were prospectively investigated by real-time PCR and direct microscopic examinations (DME) using Giemsa stain and direct immunofluorescence. All PCR negative samples were negative by microscopy. Among the 24 (45%) BAL found PCR positive, 8 were positive by microscopy (35%). The copy numbers of the target gene were between 4.4 x 10(3) and 2.8 x 10(6) per ml for the microscopically positive samples and between 8 and 9.2 x 10(3) per ml for the microscopically negative samples. In conclusion, we developed a rapid, sensitive and specific real time PCR for the diagnosis and quantification of Pneumocystis jiroveci in BAL samples.

Epidemiology, pathogenesis and prevention of congenital cytomegalovirus infection.

Cytomegalovirus is the most common cause of congenital infection. Congenital cytomegalovirus infection can follow both primary and recurrent maternal infections. It is associated with a significant burden of disease and death. The determinants of mother-to-child transmission and the pathogenesis of symptomatic fetal infection remain poorly understood. For a long time, congenital cytomegalovirus infection has been a neglected disease. Recently, the Institute of Medicine has recognized that the development of a vaccine against congenital cytomegalovirus infection is a public health priority, which should stimulate research in this area. The development of antiviral therapies to prevent symptoms in infected newborns also represents an important area of research.

Clinical characteristics of acute HSV-2 retinal necrosis.

PURPOSE: To report the clinical features and evaluate the visual outcome of eleven cases of herpes simplex virus-2 (HSV-2) related acute retinal necrosis syndrome (ARN). DESIGN: Retrospective interventional case series. METHODS: Twelve eyes of eleven patients from two European centers, diagnosed with HSV-2 related acute retinal necrosis syndrome were retrospectively reviewed. Herpes simplex virus-2 DNA was detected by polymerase chain reaction in intraocular fluids (aqueous and/or vitreous). Findings at initial examination, clinical evolution with antiviral therapy, complications and final visual acuity were evaluated. RESULTS: Herpes simplex virus-2 DNA was detected in all cases. No sample was positive for more than one virus. The mean age of disease in the first eye was 36 years (ranged from 10 to 57 years). Five patients were women and six were men. All patients were immunocompetent. Previous medical history included neonatal herpes (n = 1), previous ARN (n = 3), trauma (n = 1) and systemic corticosteroid administration before occurrence of ARN (n = 3). Preexisting pigmented chorioretinal scars were found in three cases. Patients were treated with high dose intravenous acyclovir or foscarnet +/- intravitreal ganciclovir +/- interferon. The mean follow-up was 14.5 months (from 5 to 22 months). At the end of the follow-up period, five eyes (41.7%) showed improvement of visual acuity of two or more lines. Final visual acuity was 20/60 or better in four eyes (33.3%), 20/400 or better in four eyes (33.3%) and less than 20/400 in four eyes. CONCLUSION: History of neonatal herpes, triggering events such as neurosurgery, periocular trauma, high-dose corticosteroids, and chorioretinal scars suggest that HSV-2 retinitis reflects reactivation of HSV-2 infection.

Medically assisted reproduction in the presence of chronic viral diseases.

Teams practising medically assisted reproduction techniques try to avoid viruses as much as possible. Attitudes towards chronic carriers of viruses are rapidly changing, especially for human immunodeficiency virus (HIV) patients. We focus our attention on the legitimacy of systematic screening before assisted reproductive techniques and the need for specialized approaches including an adapted laboratory for viral hazards as well as the need for a multidisciplinary team. Specificities of HIV, hepatitis C virus (HCV), hepatitis B virus (HBV) carriers and the hypothesis of a reduced fertility potential are discussed. Are male HIV carriers a new indication for assisted reproductive techniques in order to prevent virus transmission? It is largely proven that sperm gradient preparation techniques efficiently decrease viral loads and therefore have a protective effect on contamination risk during assisted reproductive techniques. Although a few thousand assisted reproductive technique cycles were performed in the world for this indication without contamination, it is still too early to demonstrate that this technology is fully safe. Two examples of contaminations during insemination are examined. Many questions remain unresolved, such as the lack of standardized techniques for semen preparation or virus detection or the relative merits of intrauterine insemination or ICSI to prevent HIV contamination during assisted reproductive techniques. The authors plead for well-structured, separate programmes of care linked to research objectives.

Lower-limb hypoplasia due to intrauterine infection with herpes simplex virus type 2: possible confusion with intrauterine varicella-zoster syndrome.

A neonate with lower-limb hypoplasia, cutaneous scars, bilateral chorioretinitis, and multiple brain abnormalities is presented. Intrauterine herpes simplex virus type 2 (HSV-2) infection was established on the basis of serological testing of the mother and viral cultures of the child's cutaneous lesions, obtained soon after birth. This is, to the best of our knowledge, the first case of a patient with in utero-acquired HSV-2 infection presenting with a limb hypoplasia. It illustrates that, in addition to congenital varicella-zoster syndrome, HSV-2 infection should also be considered in patients presenting with limb hypoplasia.

Mature CD8(+) T lymphocyte response to viral infection during fetal life.

Immunization of newborns against viral infections may be hampered by ineffective CD8(+) T cell responses. To characterize the function of CD8(+) T lymphocytes in early life, we studied newborns with congenital human cytomegalovirus (HCMV) infection. We demonstrate that HCMV infection in utero leads to the expansion and the differentiation of mature HCMV-specific CD8(+) T cells, which have similar characteristics to those detected in adults. High frequencies of HCMV-specific CD8(+) T cells were detected by ex vivo tetramer staining as early as after 28 weeks of gestation. During the acute phase of infection, these cells had an early differentiation phenotype (CD28(-)CD27(+)CD45RO(+), perforin(low)), and they acquired a late differentiation phenotype (CD28(-)CD27(-)CD45RA(+), perforin(high)) during the course of the infection. The differentiated cells showed potent perforin-dependent cytolytic activity and produced antiviral cytokines. The finding of a mature and functional CD8(+) T cell response to HCMV suggests that the machinery required to prime such responses is in place during fetal life and could be used to immunize newborns against viral pathogens.

Human herpesvirus-6 infection after lung and heart-lung transplantation: a prospective longitudinal study.

BACKGROUND: Although human herpesvirus (HHV)-6 is now recognized as a frequent pathogen after transplantation, the real impact of this infection in patients undergoing transplantation remains unclear. METHODS: During 27 months, 30 consecutive heart-lung- and lung-transplant recipients were included on the day of transplantation and prospectively followed during 100 days for HHV-6 infection. RESULTS: HHV-6 infection occurred in 20 (66%) patients after a median delay of 18 days after transplantation. The virus was detected by polymerase chain reaction or culture, or both, in 15.7 % of blood specimens, in 14.5% of bronchoalveolar lavage fluids, and in many organs at postmortem examination; it was found by culture in eight patients. No clinical manifestations could clearly be associated with HHV-6 alone. However, patients with HHV-6 infection had a higher mortality rate than patients without HHV-6 infection (7 of 20 vs. 0 of 10; P=0.04), and all the deceased patients died during periods of HHV-6 infection. We did not observe higher incidence of infectious or graft-rejection episodes in HHV-6-positive patients. However, eight of nine viral or fungal infections occurred during HHV-6 infection and three were directly responsible for death. CONCLUSION: Although frequently detected after transplantation, HHV-6 was not associated with any specific clinical manifestation. The higher mortality rate observed in patients with HHV-6 infection was not related to a higher incidence of bacterial infections or graft rejection but might be associated with more viral and fungal infections.

Transient cerebral arteriopathy in infancy associated with enteroviral infection.

We report the case of an 18-month-old boy who presented aphasia and right hemiplegia of acute onset. The neurological deficit completely resolved after a few hours, but identical transient neurological deficits and seizures occurred during the following days. Imaging showed proximal stenosis of the medial cerebral artery and deep ischaemic lesions in the territory of this artery. Analysis of the cerebrospinal fluid showed pleocytosis and an active enteroviral infection with positive RNA detection. The evolution was consistent with transient cerebral arteriopathy of childhood as magnetic resonance angiography showed normalization of the arterial lesions. This is the first report of an enteroviral infection associated with this entity. We want to stress the importance of performing a cerebrospinal fluid analysis when an ischaemic stroke of unclear aetiology occurs in a child.

Atypical recurrent varicella in 4 patients with hemopathies.

Relapsing varicella may occur in children with HIV infection and more rarely in younger adults. Our aim was to report unusual clinical, histologic, and virologic aspects of 4 elderly patients with malignant hemopathies who had an unusual form of recurrent varicella develop. Conventional microscopy, immunohistochemistry, and in situ hybridization were applied to smears and skin biopsy specimens. The patients presented a few dozen, scattered, large, papulovesicular lesions with central crusting. No zoster-associated pain or dermatomal distribution of the lesions was noted. Conventional microscopy revealed vascular changes and epidermal alterations typical for alpha-herpes virus infection. The varicella zoster virus major viral envelope glycoproteins gE and gB, and the immediate-early varicella zoster virus IE63 protein and the corresponding genome sequence for gE were detected on Tzanck smears; they were localized in endothelial cells and keratinocytes on skin biopsy specimens. The varicella zoster virus infection in endothelial cells, the vascular involvement, and the widespread distribution of the lesions suggest that the reported eruptions are vascular rather than neural in origin. These findings invalidate the diagnosis of herpes zoster but strongly support the diagnosis of recurrent varicella in an indolent and yet unreported presentation. Furthermore, these eruptions differ from relapsing varicella in children and young adults by the age of the patients, the paucity of clinical lesions, the larger diameter of the lesions and their peculiar clinical aspect, the significantly longer time interval between primary varicella and the recurrence, the prolonged healing time of the lesions, their mild disease course, and the fact that all the lesions are in the same stage of development.

Use of polymerase chain reaction for diagnosis of disseminated adenovirus infection.

We report a fatal case of disseminated adenovirus infection with fulminant hepatic failure in an 8-month-old child after peripheral blood stem cell transplantation. The virus was identified in blood, urine, respiratory aspirate and stool samples and was typed as adenovirus type 2 through PCR and sequencing of part of the hexon gene, with the use of degenerated consensus primers.