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Lazzarotto T, Varani S, Gabrielli L, Pignatelli S, Landini MP. The tegument protein ppUL25 of human cytomegalovirus (CMV) is a major target antigen for the anti-CMV antibody response. J Gen Virol 2001; 82:335-338. [PMID: 11161271 DOI: 10.1099/0022-1317-82-2-335] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A viral protein of approximately 82 kDa is the only structural protein of human cytomegalovirus (CMV) that is strongly immunogenic during natural infection and the corresponding gene of which is still unknown. In this work, strong evidence is presented that this protein is the product of UL25.
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Genser B, Truschnig-Wilders M, Stünzner D, Landini MP, Halwachs-Baumann G. Evaluation of five commercial enzyme immunoassays for the detection of human cytomegalovirus-specific IgM antibodies in the absence of a commercially available gold standard. Clin Chem Lab Med 2001; 39:62-70. [PMID: 11256803 DOI: 10.1515/cclm.2001.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In the recent years the number of commercially available immunoassays for the detection of human cytomegalovirus (HCMV)-specific immunoglobulin M (IgM) antibodies has rapidly increased. The aim of the present study was to evaluate five commercial immunoassays for the serological diagnosis of HCMV-infection. These methods, namely the IMx CMV IgM assay, the AxSYM CMV IgM assay (both Abbott), the Gull CMV IgM, the CMV-IgM-ELA test PCS Medac and the Biotest Anti-HCMV recombinant IgM ELISA, were compared for their diagnostic effectiveness and interference with substances eventually producing cross-reactions with HCMV-IgM (Epstein-Barr-virus (EBV)-IgM, rheumatoid factor (RF)). In addition, repeated measurements on samples from kidney and heart transplant recipients with active HCMV infection were examined to compare the temporal development of the HCMV-IgM measured with the five assay systems. Since there is no commercially available gold standard, it was assumed that the true classification, of whether the patient sample is HCMV-IgM positive or negative, was unknown. Hence sensitivity and specificity were assessed based on a maximum likelihood approach using a "latent class" model. The cross-reactions were quantified by a Bayesian statistical model using prior information for the expected prevalences in the EBV-IgM and rheumatoid factor sample groups. The results of the study demonstrated that there are great differences in sensitivity and specificity as well as in cross-reactions with EBV-IgM and RF between the tested ELISAs.
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128
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Dal Monte P, Pignatelli S, Mach M, Landini MP. The product of human cytomegalovirus UL73 is a new polymorphic structural glycoprotein (gpUL73). JOURNAL OF HUMAN VIROLOGY 2001; 4:26-34. [PMID: 11213930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVES This work focuses on human cytomegalovirus (HCMV) UL73, which encodes for a putative transmembrane glycoprotein that is highly conserved among herpesviruses. STUDY DESIGN pUL73 expression was analyzed both in transiently transfected and in HCMV-infected cells using a pUL73-specific antiserum by immunoblot and immunofluorescence. Sequencing analysis from several clinical isolates and laboratory-adapted strains was also performed. RESULTS pUL73 expressed in transiently transfected cells consists in a polypeptide of the expected size (15-18 kd) with cytoplasmic localization. In infected cells, pUL73 is expressed with true-late kinetics and localizes both in perinuclear granular formations and on the cell surface. A broad band (39-53 kd), sensitive to O-glycosidase digestion was detected in purified virus. In addition, sequence analysis showed that the N-terminal portion of pUL73 from clinical isolates is highly polymorphic. CONCLUSIONS UL73 encodes for a new structural glycoprotein (gpUL73) expressed on the cell surface of infected cells and highly polymorphic among clinical isolates.
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Lazzarotto T, Galli C, Pulvirenti R, Rescaldani R, Vezzo R, La Gioia A, Martinelli C, La Rocca S, Agresti G, Grillner L, Nordin M, van Ranst M, Combs B, Maine GT, Landini MP. Evaluation of the Abbott AxSYM cytomegalovirus (CMV) immunoglobulin M (IgM) assay in conjunction with other CMV IgM tests and a CMV IgG avidity assay. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2001; 8:196-8. [PMID: 11139220 PMCID: PMC96035 DOI: 10.1128/cdli.8.1.196-198.2001] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The measurement of the avidity of cytomegalovirus (CMV) immunoglobulin G (IgG) antibodies has been shown by several investigators to be useful in identifying and excluding primary CMV infections in pregnant women. In this work, we examined the diagnostic utility of reflex testing of CMV IgM-positive specimens from pregnant women by using a CMV IgG avidity assay. The utility of this approach was directly dependent on the sensitivity of the CMV IgM assay employed during the initial screen. The higher initial reactivity rate of the AxSYM CMV IgM assay was necessary in order to detect CMV IgM in specimens containing low-avidity CMV IgG antibodies, indicative of a primary CMV infection, which other CMV IgM assays (Behring, Vidas, Captia, and Eurogenetics) fail to detect in some cases. The use of the AxSYM CMV IgM assay, followed by an avidity test, should result in more accurate diagnosis of CMV infection in pregnant women.
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Emery VC, Cope AV, Sabin CA, Burroughs AK, Rolles K, Lazzarotto T, Landini MP, Brojanac S, Wise J, Maine GT. Relationship between IgM antibody to human cytomegalovirus, virus load, donor and recipient serostatus, and administration of methylprednisolone as risk factors for cytomegalovirus disease after liver transplantation. J Infect Dis 2000; 182:1610-5. [PMID: 11069231 DOI: 10.1086/317636] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/1999] [Revised: 07/07/2000] [Indexed: 11/03/2022] Open
Abstract
A retrospective study was performed on a selected cohort of 40 liver transplant recipients derived from the previous prospective follow-up of 162 liver transplant patients. The criterion for selection of this cohort was the presence of human cytomegalovirus (HCMV) DNAemia after transplantation, as determined by qualitative polymerase chain reaction (PCR). These 40 patients were followed longitudinally by quantitative PCR and by the new recombinant antigen-based AxSYM immunoassay for IgM to HCMV. The detection of IgM to CMV after transplantation was significantly associated with the development of HCMV disease in patients who had evidence of active HCMV replication in the blood by PCR (P=.01). On the basis of multivariate logistic regression analyses, the maximum titer of IgM detected after transplantation was a risk factor that was independent of augmented methylprednisolone and donor seropositivity. However, in multivariate analyses, elevated virus load continued to be the predominant risk factor for progression to HCMV disease.
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Vivarelli M, De Ruvo N, Lazzarotto T, Bellusci R, Landini MP, Varani S, Cavallari A. Abstension from treatment of low-level pp65 cytomegalovirus antigenemia after liver transplantation: a prospective study. Transplantation 2000; 70:1183-7. [PMID: 11063338 DOI: 10.1097/00007890-200010270-00010] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Ganciclovir is a highly effective and relatively safe drug to treat cytomegalovirus (CMV) infection in liver transplant patients; CMV resistance to ganciclovir is progressively emerging due to the extensive use of the drug in transplant and AIDS patients; CMV pp65 antigenemia allows early diagnosis of CMV infection and quantitation of the viral load; preemptive antigenemia-guided therapy of CMV infection can prevent CMV disease but the threshold of antigenemia value above which treatment has to be instituted is unclear. METHODS To demonstrate the safety of abstention from preemptive treatment in the presence of low levels of antigenemia 77 consecutive liver transplant recipients were prospectively evaluated. Antigenemia was tested twice a week from transplantation until discharge, then once a week until the third postoperative month. In absence of risk factors for CMV disease, namely donor positive/recipient negative CMV serology, treatment with antibodies to lymphocytes and retransplantation, only patients with antigenemia of more than 50 or symptoms possibly related to CMV infection had preemptive treatment. RESULTS A total of 32 patients had at least one positive antigenemia test with a value less than 50; 22 (68.7%) spontaneously cleared the virus, 3 were treated with i.v. ganciclovir for the presence of fever, and the other 7 (21,8%) progressed to values of antigenemia of more than 50 and were treated even if asymptomatic. No CMV disease was observed in these patients. CONCLUSION CMV antigenemia less than 50 in liver transplant recipients with low and intermediate risk for CMV disease does not mandate preemptive ganciclovir treatment. Close surveillance with repeated determination of antigenemia until its negativization and careful clinical and laboratory monitoring is advisable.
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Varani S, Lazzarotto T, Margotti M, Masi L, Gramantieri L, Bolondi L, Landini MP. Laboratory signs of acute or recent cytomegalovirus infection are common in cirrhosis of the liver. J Med Virol 2000. [PMID: 10935984 DOI: 10.1002/1096-9071(200009)62:1<25::aid-jmv4>3.0.co;2-e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Human cytomegalovirus (CMV) is an ubiquitous pathogen that can cause severe and often fatal infections in immunocompromised patients. Patients with cirrhosis often show various degrees of impaired cellular immunity that could lead to acute CMV reactivation. The aim of the present study was to determine whether laboratory findings of active CMV infections are common in patients with cirrhosis. Fifty-five patients with cirrhosis were studied for acute CMV infection by virological (antigenemia and quantitative polymerase chain reaction in polymorphonuclear leukocytes) and serological (detection of anti-CMV IgM by immunoblot) methods. The same tests were carried out on 50 blood donors and on 20 chronic hepatitis patients, considered as control populations. Acute or recent CMV infection had occurred in 31 (56%) of 55 patients with cirrhosis, whereas only 1 out of 20 (5%) patients with chronic non-cirrhotic liver disease and none of the 50 blood donors had laboratory signs of active CMV infection. The difference between patients with cirrhosis and the control groups was significant (P < 0.001, chi(2) test). CMV in patients with cirrhosis was not related to age, gender, hepatitis C virus infection or hepatocellular carcinoma. There was no significant correlation between impairment of liver function and the presence of active CMV infection. Patients with cirrhosis should be considered at risk for CMV infection, that seems to be mild and asymptomatic.
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Varani S, Lazzarotto T, Margotti M, Masi L, Gramantieri L, Bolondi L, Landini MP. Laboratory signs of acute or recent cytomegalovirus infection are common in cirrhosis of the liver. J Med Virol 2000; 62:25-8. [PMID: 10935984 DOI: 10.1002/1096-9071(200009)62:1<25::aid-jmv4>3.0.co;2-e] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Human cytomegalovirus (CMV) is an ubiquitous pathogen that can cause severe and often fatal infections in immunocompromised patients. Patients with cirrhosis often show various degrees of impaired cellular immunity that could lead to acute CMV reactivation. The aim of the present study was to determine whether laboratory findings of active CMV infections are common in patients with cirrhosis. Fifty-five patients with cirrhosis were studied for acute CMV infection by virological (antigenemia and quantitative polymerase chain reaction in polymorphonuclear leukocytes) and serological (detection of anti-CMV IgM by immunoblot) methods. The same tests were carried out on 50 blood donors and on 20 chronic hepatitis patients, considered as control populations. Acute or recent CMV infection had occurred in 31 (56%) of 55 patients with cirrhosis, whereas only 1 out of 20 (5%) patients with chronic non-cirrhotic liver disease and none of the 50 blood donors had laboratory signs of active CMV infection. The difference between patients with cirrhosis and the control groups was significant (P < 0.001, chi(2) test). CMV in patients with cirrhosis was not related to age, gender, hepatitis C virus infection or hepatocellular carcinoma. There was no significant correlation between impairment of liver function and the presence of active CMV infection. Patients with cirrhosis should be considered at risk for CMV infection, that seems to be mild and asymptomatic.
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Lazzarotto T, Spezzacatena P, Pradelli P, Abate DA, Gabrielli L, Varani S, Landini MP. Cytomegalovirus infection in pregnancy: a still complicated diagnostic problem. Intervirology 2000; 41:149-57. [PMID: 10213889 DOI: 10.1159/000024929] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The diagnostic problems linked to human cytomegalovirus (HCMV) in pregnancy are many and not all have been fully defined. In long-term seropositive women there is a tacit agreement that no laboratory testing for HCMV should be carried out. In seronegative women a test for HCMV-specific IgG should be performed at least twice during the first 4 months of pregnancy, and if the seronegativity persists, further follow-up might be stopped. On the other hand, if a seropositivity appears the diagnosis of a primary HCMV infection is established and prenatal diagnosis should be offered to the mother. Finally, in the case of a pregnant woman with unknown serological status, the diagnosis of HCMV infection is a complex problem and several different questions need to be addressed. In our opinion they should be screened with a reliable IgM test (confirmed by blot if necessary) followed, in the case of positivity, by an avidity assay. Pregnant women undergoing a primary HCMV infection should be encouraged to seek prenatal diagnosis to be performed by PCR and virus isolation from amniotic fluid at the 21st to 23rd week of gestation.
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Guerra B, Lazzarotto T, Quarta S, Lanari M, Bovicelli L, Nicolosi A, Landini MP. Prenatal diagnosis of symptomatic congenital cytomegalovirus infection. Am J Obstet Gynecol 2000; 183:476-82. [PMID: 10942490 DOI: 10.1067/mob.2000.106347] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate whether the amniotic viral load of mothers with primary cytomegalovirus infection correlate with fetal or neonatal outcomes. STUDY DESIGN Sixty-eight of 138 pregnant women with primary infection defined by immunoglobulin G seroconversion or the presence of immunoglobulin M with low immunoglobulin G avidity accepted amniocentesis. Polymerase chain reaction and quantitative polymerase chain reaction were used to detect amniotic fluid cytomegalovirus. Cytomegalovirus infection in neonates was determined by means of urinary viral isolation during the first week after birth or the histologic examination of tissue from aborted fetuses. RESULTS Cytomegalovirus infection was found in 16 fetuses and neonates (23%), 5 of whom had symptoms. Quantitative polymerase chain reaction showed that the presence of >/=10(3) genome equivalents predicted mother-child infection with 100% probability; >/=10(5) genome equivalents predicted the development of a symptomatic infection. CONCLUSION Fewer than expected cytomegalovirus-infected fetuses are at risk for development of cytomegaloviral disease, and this fact may be useful in counseling pregnant women with primary cytomegalovirus infection.
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Zini N, Santi S, Riccio M, Landini MP, Battista MC, Maraldi NM. pUL25 immunolocalization in human cytomegalovirus-infected and gene-transfected cells. Arch Virol 2000; 145:795-803. [PMID: 10893157 DOI: 10.1007/s007050050672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
By means of confocal and electron microscope immunocytochemistry we have studied the localization of a recently described structural protein (pUL25) of human cytomegalovirus, in both infected cells and in cells transiently transfected with UL25. pUL25 localization in infected cells was observed in typical cytoplasmic structures characterized by a very electrondense texture previously reported to accumulate other tegument proteins. At the virion level pUL25 seems to localize at the interface between the tegument and the capsid of both intracytoplasmic and extracellular virions. In UL-25-transfected cells, pUL25 has been found in characteristic para-crystalline cytoplasmic aggregates, suggesting its intrinsic ability to aggregate in a regular subunit pattern.
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Arcangeletti MC, Pinardi F, Medici MC, Pilotti E, De Conto F, Ferraglia F, Landini MP, Chezzi C, Dettori G. Cytoskeleton involvement during human cytomegalovirus replicative cycle in human embryo fibroblasts. THE NEW MICROBIOLOGICA 2000; 23:241-56. [PMID: 10939039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Several studies indicate that viruses can induce different cytoskeletal modifications. The present investigation examines the possible involvement of human embryo fibroblast cytoskeleton in the replication of human cytomegalovirus (HCMV). Significant cytoskeletal modifications occur in infected cells; specifically, microfilament depolymerization is observed very early during the HCMV replicative cycle, whilst microtubules and intermediate filaments do not undergo any change for longer times after infection. Our data focus, in particular, on microfilament depolymerization, which starts within the first hour of the replicative cycle, and on the significance of this event, as a CMV-induced mechanism to modify the post-transcriptional regulation of cellular gene expression for its own benefit. Among the possible mechanisms exploited by HCMV to induce microfilament modifications, one might involve the cellular ADP-ribosylation activity, which is increased by HCMV very early in the infectious cycle. Experiments carried out on HCMV-infected cells, in the presence of ADP-ribosylation inhibitors, seem to confirm this hypothesis.
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Lazzarotto T, Varani S, Guerra B, Nicolosi A, Lanari M, Landini MP. Prenatal indicators of congenital cytomegalovirus infection. J Pediatr 2000; 137:90-5. [PMID: 10891828 DOI: 10.1067/mpd.2000.107110] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To assess the validity of a diagnostic protocol designed to predict the outcome of newborns of mothers suspected to have primary cytomegalovirus (CMV) infection during the first 4 months of pregnancy. STUDY DESIGN Anti-CMV immunoglobulin (Ig) M detection by enzyme immunoassay and immunoblot together with the determination of anti-CMV IgG avidity allowed us to classify 456 women as (1) uninfected, (2) undergoing either a primary or a recurrent infection, or (3) having an undefined serologic condition. Prenatal diagnosis was carried out at 21 to 23 weeks' gestation for women. The presence of the virus in the amniotic fluid was determined by culture, polymerase chain reaction, and quantitative polymerase chain reaction. Macroscopic and histologic examinations were undertaken on tissue from aborted fetuses, whereas for newborns culture was performed on urine sampled during the first week of life. RESULTS Congenital infections were found exclusively among women undergoing a primary infection. The quantitative determination of CMV DNA in the amniotic fluid of at least 10(3) genome equivalents gave a 100% certainty of detecting an infected fetus. Higher viral loads were associated with fetuses or newborns with symptoms. CONCLUSIONS IgM tests and the IgG avidity determination can identify all women at risk of transmitting CMV. Furthermore, a high CMV DNA load in amniotic fluid could be an indicator of symptomatic congenital infection at a relatively early stage of pregnancy.
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Landini MP, Lazzarotto T, Xu J, Geballe AP, Mocarski ES. Humoral immune response to proteins of human cytomegalovirus latency-associated transcripts. Biol Blood Marrow Transplant 2000; 6:100-8. [PMID: 10741618 DOI: 10.1016/s1083-8791(00)70072-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Latent human cytomegalovirus (CMV) infection of hematopoietic progenitor cells is associated with the presence of latency-associated transcripts that may express 6 proteins larger than 44 amino acids in size (open reading frame [ORF] 55, ORF45, ORF94, ORF59, ORF154, ORF152/UL124). The serologic response to these proteins was evaluated in healthy seropositive individuals as well as in individuals undergoing active CMV infection. Individual recombinant GST-fusion proteins, prepared from bacteria, were found by enzyme-linked immunosorbent assay to be recognized by between 8% and 44% long-term healthy seropositive individuals, with ORF94 and ORF55 being the most broadly and significantly recognized. Although nearly all of serum samples (85%) recognized at least 1 of these proteins, none reacted with all 6. Patterns of antibody prevalence to these proteins in long-term seropositive individuals were similar to many antigens expressed during productive replication (IE1, ppUL57, ppUL83/pp65), but none were broadly detected by a majority of individuals, a characteristic of only a few productive-phase antigens, including ppUL44/ICP36 and ppUL32/pp150. Consistent with prevalence in long-term seropositive individuals, commercial preparations of pooled human gamma globulin were also found to recognize latency-associated proteins. Serologic reactivity to latency-associated proteins was slow to develop following primary infection, in a pattern distinct from any of the characterized replication-phase proteins tested here, and was boosted late after secondary infection or reactivation in solid-organ transplant recipients without showing a correlation with viremia or disease. These results provide evidence that proteins expressed from the latent region during natural infection exhibit immunogenicity comparable with most other characterized viral antigens, although the narrow response to individual latency-associated proteins likely precludes their use in serologic assays to investigate clinical correlates or outcome in transplant recipients.
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140
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Lazzarotto T, Varani S, Spezzacatena P, Gabrielli L, Pradelli P, Guerra B, Landini MP. Maternal IgG avidity and IgM detected by blot as diagnostic tools to identify pregnant women at risk of transmitting cytomegalovirus. Viral Immunol 2000; 13:137-41. [PMID: 10733175 DOI: 10.1089/vim.2000.13.137] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In this study, we determined the avidity index (AI) of anticytomegalovirus (CMV) immunoglobulin G (IgG) and the anti-CMV immunoglobulin M (IgM) profile in 124 pregnant women, 87 of whom were considered at risk of transmitting CMV infection to their offspring and 37 of whom were at no risk. IgG avidity and blot for IgM were performed on two serum samples from each woman, at 6-18 weeks' gestation and at 20-23 weeks' gestation. Pregnancy outcomes were monitored. The results obtained showed that the determination of anti-CMV IgG avidity at 6-18 weeks' gestation can identify all women who would have an infected fetus/newborn (100% sensitivity), whereas IgM detected by blot had poorer results (69% sensitivity). Interestingly, at 20-23 weeks' gestation, the sensitivity of IgM detection by blot was higher than that obtained by avidity (75 % and 63%, respectively) and the combination of IgG avidity and IgM by blot yielded the best results (81% sensitivity).
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141
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Lazzarotto T, Varani S, Gabrielli L, Spezzacatena P, Landini MP. New advances in the diagnosis of congenital cytomegalovirus infection. Intervirology 2000; 42:390-7. [PMID: 10702722 DOI: 10.1159/000053976] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
With the advances in anticytomegalovirus (anti-CMV) serology, the new recombinant IgM tests seem likely to become the screening tests for pregnant women whose prepregnancy serological status for CMV is unknown. When a woman is found to be IgM-positive, further diagnostic evaluation focused on determining whether this is due to a primary infection should be carried out. Maternal primary infections that were difficult to determine until a few years ago unless documented by seroconversion can now be readily diagnosed from the presence of low-avidity anti-CMV antibody which persists for approximately 20 weeks after primary infection. In primarily infected mothers prenatal diagnosis can be performed between 21 and 23 weeks of gestation, and the amniotic fluid (AF) represents the pathological material of choice to determine intrauterine virus transmission. In AF, the virus can be detected by culture and/or PCR. Both procedures differentiate uninfected from infected fetuses, but cannot predict fetal outcome. The determination of the viral load in AF carried out by quantitative PCR is more promising and could represent an important starting point for preemptive fetal therapy.
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142
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Varani S, Spezzacatena P, Manfredi R, Chiodo F, Mastroianni A, Ballarini P, Boschini A, Lazzarotto T, Landini MP. The incidence of cytomegalovirus (CMV) antigenemia and CMV disease is reduced by highly active antiretroviral therapy. Eur J Epidemiol 2000; 16:433-7. [PMID: 10997830 DOI: 10.1023/a:1007619323939] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Cytomegalovirus (CMV) infection was one of the most common opportunistic infections in AIDS patients, leading to blindness or life-threatening disease in about 40% of patients in the later stages of AIDS before highly active antiretroviral therapy (HAART). In a retrospective multicenter study we investigated the incidence of CMV retinitis and organ involvement in Northern Italy before (1995 and 1996) and after the introduction of HAART (1997 and 1998) as well as the data regarding CMV antigenemia. We found a sharp drop in the incidence of CMV disease in AIDS patients as well as a decline in the incidence of relapses of CMV-disease after the widespread introduction of HAART. Moreover, there was a decrease in the incidence of antigenemia-positive cases in AIDS patients in the era of HAART and the median CMV viral load was significantly higher in patients who didn't receive HAART than in patients who received HAART (p = 0.001, t test).
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Maine GT, Stricker R, Schuler M, Spesard J, Brojanac S, Iriarte B, Herwig K, Gramins T, Combs B, Wise J, Simmons H, Gram T, Lonze J, Ruzicki D, Byrne B, Clifton JD, Chovan LE, Wachta D, Holas C, Wang D, Wilson T, Tomazic-Allen S, Clements MA, Wright GL, Lazzarotto T, Ripalti A, Landini MP. Development and clinical evaluation of a recombinant-antigen-based cytomegalovirus immunoglobulin M automated immunoassay using the Abbott AxSYM analyzer. J Clin Microbiol 2000; 38:1476-81. [PMID: 10747129 PMCID: PMC86469 DOI: 10.1128/jcm.38.4.1476-1481.2000] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/1999] [Accepted: 01/24/2000] [Indexed: 11/20/2022] Open
Abstract
A new microparticle enzyme immunoassay (MEIA), the Cytomegalovirus (CMV) Immunoglobulin M (IgM) test, was developed on the Abbott AxSYM analyzer. This test uses recombinant CMV antigens derived from portions of four structural and nonstructural proteins of CMV: pUL32 (pp150), pUL44 (pp52), pUL83 (pp65), and pUL80a (pp38). A total of 1, 608 specimens from random volunteer blood donors (n = 300), pregnant women (n = 1,118), transplant recipients (n = 6), and patients with various clinical conditions and disease states (n = 184) were tested during development and evaluation of this new assay. In a preliminary clinical evaluation we tested specimens collected prospectively from pregnant women (n = 799) and selected CMV IgM-positive archived specimens from pregnant women (n = 39). The results from the new CMV IgM immunoassay were compared to the results of a consensus interpretation of the results obtained with three commercial CMV IgM immunoassays. The results for specimens with discordant results were resolved by a CMV IgM immunoblot assay. The relative sensitivity, specificity, and agreement for the AxSYM CMV IgM assay were 94.29, 96.28, and 96.19%, respectively, and the resolved sensitivity, specificity, and agreement were 95.83, 97.47, and 97.37%, respectively. We also tested serial specimens from women who experienced seroconversion or a recent CMV infection during gestation (n = 17) and potentially cross-reactive specimens negative for CMV IgM antibody by the consensus tests (n = 184). The AxSYM CMV IgM assay was very sensitive for the detection of CMV IgM during primary CMV infection, as shown by the detection of CMV IgM at the same time as or just prior to the detection of CMV IgG. Specimens from individuals with lupus (n = 16) or parvovirus B19 infection (n = 6) or specimens containing hyper IgM (n = 9), hyper IgG (n = 8), or rheumatoid factor (n = 55) did not cross-react with the AxSYM assay. One specimen each from individuals infected with Epstein-Barr virus (n = 26), measles virus (n = 10), herpes simplex virus (n = 12), or varicella-zoster virus (n = 13) infection, one specimen from an influenza vaccinee (n = 14), and one specimen containing antinuclear antibody cross-reacted with the assay. The overall rate of cross-reactivity of the specimens with the assay was 3.3% (6 of 184). The AxSYM CMV IgM assay is a sensitive and specific assay for the detection of CMV-specific IgM.
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144
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Muratori L, Parola M, Ripalti A, Robino G, Muratori P, Bellomo G, Carini R, Lenzi M, Landini MP, Albano E, Bianchi FB. Liver/kidney microsomal antibody type 1 targets CYP2D6 on hepatocyte plasma membrane. Gut 2000; 46:553-61. [PMID: 10716687 PMCID: PMC1727874 DOI: 10.1136/gut.46.4.553] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Liver/kidney microsomal antibody type 1 (LKM1) is the marker of type 2 autoimmune hepatitis (AIH) and is detected in up to 6% of patients with hepatitis C virus (HCV) infection. It recognises linear and conformational epitopes of cytochrome P450IID6 (CYP2D6) and may have liver damaging activity, provided that CYP2D6 is accessible to effector mechanisms of autoimmune attack. METHODS The presence of LKM1 in the plasma membrane was investigated by indirect immunofluorescence and confocal laser microscopy of isolated rat hepatocytes probed with 10 LKM1 positive sera (five from patients with AIH and five from patients with chronic HCV infection) and a rabbit polyclonal anti-CYP2D6 serum. RESULTS Serum from both types of patient stained the plasma membrane of non-permeabilised cells, where the fluorescent signal could be visualised as discrete clumps. Conversely, permeabilised hepatocytes showed diffuse submembranous/cytoplasmic staining. Adsorption with recombinant CYP2D6 substantially reduced plasma membrane staining and LKM1 immunoblot reactivity. Plasma membrane staining of LKM1 colocalised with that of anti-CYP2D6. Immunoprecipitation experiments showed that a single 50 kDa protein recognised by anti-CYP2D6 can be isolated from the plasma membrane of intact hepatocytes. CONCLUSIONS AIH and HCV related LKM1 recognise CYP2D6 exposed on the plasma membrane of isolated hepatocytes. This observation supports the notion that anti-CYP2D6 autoreactivity may be involved in the pathogenesis of liver damage.
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145
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Landini MP, Jahn G. [The eclectic cellular tropism of cytomegalovirus]. Pathologica 2000; 92:51-7. [PMID: 10838868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
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146
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Reschke M, Revello MG, Percivalle E, Radsak K, Landini MP. Constitutive expression of human cytomegalovirus (HCMV) glycoprotein gpUL75 (gH) in astrocytoma cells: a study of the specific humoral immune response. Viral Immunol 1999; 12:249-62. [PMID: 10532653 DOI: 10.1089/vim.1999.12.249] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The humoral immune response to gpUL75 (gH) was determined in different groups of human cytomegalovirus (HCMV) infected subjects using a full-length glycoprotein constitutively expressed in an astrocytoma cell line. The recombinant molecule consisted of two distinct isoforms resembling the authentic protein of infected cells. Separated from the interactions of other viral gene products gH failed to form an oligomeric complex, thus exhibiting exclusively epitopes present on the monomer. Ninety five percent of serum samples from latently-infected healthy adults revealed the presence of gH-specific IgG. Moreover, examination of sequential sera from immunocompromised and immunocompetent individuals undergoing active HCMV infection demonstrated that antibodies to gH occurred in most cases simultaneously with those to the abundant surface antigen gpUL55 (gB) and at similar titres. Appearance of this response was correlated with a considerable increase of the virus-neutralizing activity and most likely associated with restriction of viral dissemination during subsequent viremic episodes. Together, these results suggest that glycoprotein H of HCMV is like gB, a highly immunogenic component of the infectious particle.
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147
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Zini N, Battista MC, Santi S, Riccio M, Bergamini G, Landini MP, Maraldi NM. The novel structural protein of human cytomegalovirus, pUL25, is localized in the viral tegument. J Virol 1999; 73:6073-5. [PMID: 10364360 PMCID: PMC112669 DOI: 10.1128/jvi.73.7.6073-6075.1999] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human cytomegalovirus UL25 codes for a structural phosphoprotein of 85 kDa (C. J. Baldick and T. Shenk, J. Virol. 70:6097-6105, 1996; M. C. Battista et al., J. Virol. 73:3800-3809, 1999). In this study we analyzed the intracellular and intraviral localization of pUL25 by confocal and immunoelectron microscopy and found that pUL25 is a component of the viral tegument and the dense body matrix, acquired during the late cytoplasmic phase of virus maturation.
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148
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Battista MC, Bergamini G, Boccuni MC, Campanini F, Ripalti A, Landini MP. Expression and characterization of a novel structural protein of human cytomegalovirus, pUL25. J Virol 1999; 73:3800-9. [PMID: 10196274 PMCID: PMC104157 DOI: 10.1128/jvi.73.5.3800-3809.1999] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human cytomegalovirus (HCMV) UL25 has recently been found to encode a new structural protein that is present in both virion and defective viral particles (C. J. Baldick and T. Shenk, J. Virol. 70:6097-6105, 1996). In the present work a polyclonal antibody was raised against a prokaryotic pUL25 fusion protein in order to investigate the biosynthesis and localization of the UL25 product (pUL25) during HCMV replication in human fibroblasts. Furthermore, pUL25 was transiently expressed in its native form and fused to the FLAG epitope, in COS7 and U373MG cells, in order to compare the properties of the isolated protein and that produced during infection. Immunoblotting analysis revealed a group of polypeptides, ranging from 80 to 100 kDa, in both transfected and infected cells; in vivo labeling experiments with infected cells demonstrated they are posttranslationally modified by phosphorylation. The transcriptional analysis of the UL25 open reading frame combined with the study of pUL25 biosynthesis showed true late kinetics for this protein in infected human fibroblasts. By indirect immunofluorescence both recombinant and viral pUL25 were detected exclusively in the cytoplasm of transfected or infected cells. Interestingly, pUL25 was shown to localize in typical condensed structures in the perinuclear region as already observed for other HCMV tegument proteins. Colocalization of ppUL99 in the same vacuoles suggests that these structure are endosomal cisternae, which are proposed to be a preferential site of viral particle envelopment. Our data suggest that pUL25 is most likely a novel tegument protein and possibly plays a key role in the process of envelopment.
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Landini MP. Characterization of a novel tegument protein of HCMV: pUL25. J Clin Virol 1999. [DOI: 10.1016/s1386-6532(99)90438-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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150
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Dal Monte P, Varani S, Lazzarotto T, Pignatelli S, Landini MP. Prokaryotic expression of human cytomegalovirus pUS22 and its reactivity with human antibody. Arch Virol 1999; 143:2413-9. [PMID: 9930196 DOI: 10.1007/s007050050470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This work demonstrates that antibodies to the product of the recombinant pUS22 of human cytomegalovirus (HCMV) are present in human sera during natural infection. US22 gene product has been identified as a member of the US22 family which may be secreted from infected cells. It is an early protein of 593 amino acids, 76 Kd in molecular weight. US22 seems to be an antigen which stimulates a good IgG response. In fact specific IgGs were found in approximately 40% of the CMV positive sera irrespective of their anti-CMV IgG titer. Specific IgM antibodies to pUS22 were observed exclusively during primary infection and in the sera with a high anti-CMV IgM titer. pUS22 could be considered for inclusion in a cocktail of CMV recombinant proteins to determine seropositivity to CMV and also to diagnose an active CMV infection.
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