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PubMed1994

Laboratory diagnosis of human hepatitis viruses.

Conventional serologic methods of antigen or antibody detection are now widely applied for diagnosis of hepatitis viruses A, B, C, and D. Nucleic acid quantitation has become very useful for monitoring response to antiviral therapy in cases of hepatitis B and C. Special confirmatory testing of HCV serologies can be quite specific, but overall serologies for HCV lack sensitivity for early diagnosis. Thus HCV RNA detection may ultimately be the preferred method for HCV diagnosis and for screening blood donors. Unfortunately, HEV diagnosis may rest on the efforts of research laboratories for electron microscopy, Western blot, or nucleic acid detection.

Hepatitis A↗
PubMed1995

Therapy of hepatitis C.

In acute hepatitis C, the efficacy of alpha interferon has not been definitively demonstrated. However, several small trials have suggested that interferon may decrease the chronicity rate of acute hepatitis C. In view of the high rate of chronic infection resulting from acute hepatitis C, it is warranted to treat patients during the acute phase of illness if they continue to have HCV RNA detectable in serum for 1 month after the onset of symptoms. The regimen of alpha interferon therapy should be 3 mu three times weekly for 24 weeks. In chronic hepatitis C, therapy with 3-5 mu of alpha interferon three times weekly for 24-48 weeks will induce a temporary remission in disease with loss of HCV RNA from serum, fall of aminotransferases into the normal range, and improvement in liver histology in 50% of patients, and a sustained remission persisting after therapy is stopped in 15% to 20% of patients. Younger patients with a short duration of disease, without cirrhosis, and with lower levels of HCV RNA in serum are the most likely to respond. Unfortunately, there are no completely reliable means of predicting which patients will derive long-term benefits from the use of interferon. Interferon remains the only approved therapy for chronic hepatitis C, although the low rate of sustained remissions and the incidence of side effects mandate a search for ways to improve the efficacy of interferon, as well as to find new, more potent agents for the treatment of this disease.

Acute Disease↗
PubMed2004

Blinded laboratory comparison of the in situ enzyme immunoassay, the VecTest wicking assay, and a reverse transcription-polymerase chain reaction assay to detect mosquitoes infected with West Nile and St. Louis encephalitis viruses.

A blinded laboratory evaluation compared the accuracy, sensitivity, and specificity of an in situ enzyme immunoassay (EIA), VecTest wicking assay, and reverse transcription-polymerase chain reaction (RT-PCR) to detect and distinguish West Nile (WN) and St. Louis encephalitis (SLE) viruses in pools of 50 mosquitoes. Adult female Culex tarsalis Coquillett were inoculated with either WN or SLE viruses, held for 0-11 d at 28 degrees C, killed by freezing, and then were added to 49 or 48 uninfected mosquitoes to make up 14 pools positive for WN virus, 14 positive for SLE virus, 14 positive for both WN and SLE viruses, and 14 negative for virus. Pools were number coded and tested blindly. Virus was not detected in known negative pools. VecTest and RT-PCR assays were comparably sensitive and accurate, detecting virus in pools containing females held for 3 d postinoculation; only RT-PCR detected SLE virus in pools on days 0-1. The VecTest and RT-PCR produced a single false-positive result for WN and SLE, respectively. RT-PCR detected RNA in samples positive by the VecTest, indicating that the detergent in the wicking buffer did not prevent RT-PCR from confirming VecTest results. Detector antibodies used in the in situ EIA cross-reacted between SLE and WN viruses, reducing accuracy. Both the VecTest and RT-PCR provided rapid and specific results, but they detected only those viruses known to be present. Plaque assay on Vero cells was comparably sensitive and had the added benefit of detecting newly emerging viruses, but this method required virus culture followed by identification, thereby delaying reporting.

Animals↗
PubMed1985

Androgen regulation of MAK mRNAs in mouse kidney.

Androgen-regulated changes in the abundance of two mRNAs in mouse kidney have been studied with the aid of a cDNA clone. The clone was isolated from a library prepared using poly(A+) RNA from kidneys of androgen-induced mice and is designated MAK-I. Unique DNA sequence from MAK-I hybridizes to multiple RNAs which are approximately 1600 and 2200 nucleotides long, and Southern blot analysis of genomic DNA suggests that there is a single gene from which the RNAs are transcribed. When the MAK RNAs are isolated by hybrid selection and translated in a cell-free system, one polypeptide of 42,000 daltons is obtained. The transcripts, in combination, comprise approximately 0.2% of poly(A+) RNA in the kidneys of male mice. Following treatment with testosterone, this level increases 3-fold. The uninduced level of MAK mRNA in female kidneys is half of that exhibited by males and is increased 8-fold by testosterone. The mRNAs are also present and their abundance is hormonally controlled in the liver. Levels of MAK RNA detected in submaxillary gland, heart, brain, muscle, and testes are unaffected by testosterone treatment. Differences in the relative amounts of the different sized mRNAs are observed for several tissues. In addition, brain and muscle contain an intermediate sized mRNA instead of the smaller one seen in other tissues. Functional androgen receptor is required for expression of MAK RNA in kidney as shown by reduced levels in Tfm mice. Hormones produced by or controlled by the pituitary gland do not appear to be involved in the regulation of MAK RNA levels.

Animals↗
PubMed1994

Synthesis and localization of C-type natriuretic peptide in mammalian kidney.

We have previously demonstrated the synthesis of atrial natriuretic factor (ANF) in the distal cortical nephron of the rat kidney. We now report the synthesis of C-type natriuretic peptide (CNP) in the rat, mouse, and human nephron. CNP mRNA was initially detected in the rat and mouse kidney, as well as in three transformed cell lines isolated from the proximal and distal nephron, using reverse transcription-polymerase chain reaction (RT-PCR). Confirmation of the kidney PCR product was performed by nucleotide sequence analysis and Southern hybridization. Northern hybridization of rat brain CNP cDNA to human kidney polyadenylated RNA detected a 1.4-kb gene transcript. Rat nephron segments were microdissected and subjected to RT-PCR to localize CNP mRNA. CNP mRNA was detected in the proximal convoluted tubule, cortical collecting duct, medullary thick limbs, and inner medullary collecting ducts. CNP, as detected by immunohistochemistry, was found to colocalize with CNP mRNA.

Animals↗
PubMed2004

Contribution of hepatitis C virus and Helicobacter Pylori co-infection as possible predisposing factors in the occurrence of gastric mucosal dysplasia.

BACKGROUND AND PURPOSE: Current views on B-cell lymphoma genesis suggest that several exogenous factors, acting in a multistep fashion upon a predisposing condition, may be involved in B-cell clonal expansion, a potentially prelymphomatous stage. This study was done to investigate the extrahepatic localization of Hepatitis C virus (HCV)in the gastric mucosa and the possibility of its involvement besides Helicobacter pylori (H. pylori) as possible predisposing factors that might play a role in the occurrence of gastric dysplasia or lymphoproliferation following gastritis and may end in carcinogenesis. PATIENTS AND METHODS: A well characterized series of 45 patients with chronic liver disease complaining of gastric dyspepsia were subjected to Upper Gastrointestinal Endoscopy and histological examination of gastric biopsy with studying the prevalence of serologic and molecular markers of HCV and H. pylori in the patients' serum and their gastric tissue. HCV-RNA detection in gastric tissue was done only for those who showed gastric dysplasia. RESULTS: Histopathological examination of the gastric biopsies revealed that 20 patients (44.4%) had chronic active gastritis, 15 patients (33.4%) had chronic gastritis and 10 patients (22.2%) had gastric dysplasia with chronic gastritis. As for hepatitis C virus, 38 patients (84.4%) were reactive for serum antibodies (HCV-Abs) and 18 patients (40%) showed Polymerase Chain Reaction (PCR) positivity. Helicobacter pylori antibody reactivity was detected in 37 patients (82.2%) while PCR positivity was detected in 24 patients (53.3%) both in their serum as well as in gastric tissues. Seventeen out of twenty cases showing chronic active gastritis were serologically positive for both H. pylori and HCV. Patients who showed dysplasia on pathological examination (n=10) were all HCV-Abs positive (p-value = 0.32), seven patients were serum HCV-RNA positive (p-value = 0.083) and 3 of them showed HCV-RNA positivity in their gastric tissue. Nine out of the patients with gastric dysplastic changes proved positive for H. pylori DNA both in serum (p-value= 0.027) and tissue (p-value= 0.029). CONCLUSIONS: We suggest that Hepatitis C virus may be considered, in addition to Helicobacter pylori, as another potential infectious co-factor in the occurrence of gastric mucosal dysplasia and thus might be associated in the multistep hypothesis of carcinogenesis.

Journal Article↗
PubMed2004

Peroxisome proliferator-activated receptor and farnesoid X receptor ligands differentially regulate sebaceous differentiation in human sebaceous gland organ cultures in vitro.

BACKGROUND: Nuclear hormone receptors are important in the regulation of epidermal differentiation and have been implicated in lipid metabolism. In particular, there is evidence suggesting that the activation of peroxisome proliferator-activated receptors (PPARs) is an important factor in the regulation of sebocyte lipogenesis. OBJECTIVES: To determine the role of PPARs, farnesoid X receptor (FXR) and other orphan nuclear hormone receptors in sebaceous gland function in vitro by investigating the biochemical effects of appropriate ligands, and by establishing the RNA and protein expression patterns of a number of nuclear receptors in sebaceous glands ex vivo. METHODS: Human chest sebaceous glands were maintained in vitro as freshly isolated and as 7-day cultured whole organs. We then studied the effects of appropriate ligands on the glandular rates of lipogenesis and DNA synthesis, as well as determining the mRNA (reverse transcription-polymerase chain reaction) and protein expression patterns (immunohistochemistry/immunoblotting) of the nuclear hormone receptors of interest. RESULTS: PPAR ligands, but not FXR ligands, inhibited sebaceous lipogenesis, in particular the PPARalpha ligands LY 171883 and WY 14643, and the PPARgamma ligands BRL 49653 and 15-deoxy-Delta-12,14-prostaglandin J(2). We detected RNA expression of PPARalpha, PPARbeta, PPARgamma, retinoid X receptor alpha, liver X receptor alpha (LXRalpha) and pregnane X receptor but not FXR in freshly isolated and 7-day maintained sebaceous glands. PPARalpha, PPARbeta, PPARgamma and LXRalpha protein were detected in nuclear extracts of sebaceous glands. CONCLUSIONS: We conclude that activation of nuclear hormone receptors, in particular activation of PPARalpha and PPARgamma, can regulate lipogenesis in human sebaceous glands. As suppression of sebum secretion is associated with reduced acne activity, the nuclear hormone receptors involved may open new avenues in the development of novel acne treatments.

Cell Differentiation↗
PubMed1996

Molecular neuroanatomy of human monoamine oxidases A and B revealed by quantitative enzyme radioautography and in situ hybridization histochemistry.

Monoamine oxidases are key enzymes in the metabolism of amine neurotransmitters and neuromodulators and are targets for drug therapy in depression, Parkinson's and Alzheimer's diseases. Knowledge of their distribution in the brain is essential to understand their physiological role. To study the regional distribution and abundance of monoamine oxidases A and B in human brain, pituitary and superior cervical ganglion, we used quantitative enzyme radioautography with radioligands [3H]Ro41-1049 and [3H]lazabemide, respectively. Furthermore, 35S-labelled oligonucleotides complementary to isoenzyme messengerRNAs were used to map the cellular location of the respective transcripts in adjacent sections by in situ hybridization histochemistry. A markedly different pattern of distribution of the isoenzymes was observed. Highest levels of monoamine oxidase A were measured in the superior cervical ganglion, locus coeruleus, interpeduncular nucleus and ventromedial hypothalamic nucleus. The corresponding messengerRNA was detected only in the noradrenergic neurons of the superior cervical ganglion and locus coeruleus. In contrast to rat brain, monoamine oxidase B was much more abundant in most human brain regions investigated. Highest levels were measured in the ependyma of ventricles, stria terminalis and in individual hypothalamic neurons. Monoamine oxidase B transcripts were detected in serotoninergic raphe neurons, histaminergic hypothalamic neurons and in dentate gyrus granule cells of the hippocampal formation. We conclude that [3H]Ro41-1049 and [3H]azabemide are extremely useful radioligands for high-resolution analyses of the abundance and distribution of catalytic sites of monoamine oxidases A and B, respectively, in human brain sections. From levels of messenger RNA detected, the cellular sites of synthesis of the isoenzymes are the noradrenergic neurons of the locus coeruleus (for monoamine oxidase A) and the serotoninergic and histaminergic neurons of the raphe and posterior hypothalamus, respectively (for monoamine oxidase B). The combination of quantitative enzyme radioautography with in situ hybridization histochemistry is a useful approach to study, with high resolution, both the physiology and pathophysiology of monoamine oxidases in human brain.

Aged↗
PubMed2003

Differential helix stabilities and sites pre-organized for tertiary interactions revealed by monitoring local nucleotide flexibility in the bI5 group I intron RNA.

The local environment at adenosine residues in the bI5 group I intron RNA was monitored as a function of Mg(2+) using both the traditional method of dimethyl sulfate (DMS) N1 methylation and a new approach, selective acylation of 2'-amine substituted nucleotides. These probes yield complementary structural information because N1 methylation reports accessibility at the base pairing face, whereas 2'-amine acylation scores overall residue flexibility. 2'-Amine acylation robustly detects RNA secondary structure and is sensitive to higher order interactions not monitored by DMS. Disruption of RNA structure due to the 2'-amine substitution is rare and can be compensated by stabilizing folding conditions. Peripheral helices that do not interact with other parts of the RNA are more stable than both base paired helices and tertiary interactions in the conserved catalytic core. The equilibrium state of the bI5 intron RNA, prior to assembly with its protein cofactor, thus features a relatively loosely packed core anchored by more stable external stem-loop structures. Adenosine residues in J4/5 and P9.0 form structures in which the nucleotide is constrained but the N1 position is accessible, consistent with pre-organization to form long-range interactions with the 5' and 3' splice sites.

Acylation↗
PubMed1997

Antiviral therapy of hepatitis C.

BACKGROUND: Chronic hepatitis C can be treated with interferon therapy, but persistent viral clearance is only achieved in 20% of patients. Which patients have a high chance of viral clearance and what other treatment might enhance the effectivity of interferon therapy are reviewed. METHODS: Data from published randomized trials on interferon mono-therapy, ribavirin mono-therapy and combination therapy of interferon-ribavirin and interferon-ursodeoxycholic acid are analysed separately and in a meta-analysis of individual data. RESULTS: Interferon mono-therapy leads to viral clearance in only 10% of patients with genotype 1 and in less than 10% in cirrhosis; patients with plasma HCV RNA detectable at 4 weeks of therapy have only 2% chance of viral clearance. Prolongation of therapy reduces relapse in treatment responders. Interferon-ribavirin combination therapy appears to enhance the efficacy 2-3 fold without increasing toxicity. CONCLUSIONS: The benefit-risk/cost ratio of interferon mono-therapy can be improved by selection of patients, monitoring plasma HCV RNA at 4 weeks, and prolonging therapy to 12 months in responders with genotype 1. Interferon-ribavirin combination is promising for its enhanced efficacy.

Antiviral Agents↗
PubMed1983

Evidence for the biochemical role of an internal sequence in yeast nuclear mRNA introns: implications for U1 RNA and metazoan mRNA splicing.

Sequence comparison of the introns of two yeast genes (rp51A and rp51B) coding for the same ribosomal protein shows homology only in the last 50 bases of the intron. This region of the intron contains an internal conserved sequence (ICS) present near the 3' end of all sequenced yeast nuclear mRNA introns. Removal of a 29 bp sequence containing the ICS prevents splicing of an intron-containing hybrid gene. In cells containing the wild-type gene, we have detected RNA molecules that we suggest are normal splicing intermediates, generated by an endonucleolytic cut in the primary transcript at the ICS. The homology of the ICS with a sequence near the 5' end of U1 snRNA suggests a model in which an interaction in cis between the ICS and the 5' splice junction in yeast is the counterpart of the interaction in trans between U1 and 5' splice junctions in higher eucaryotes.

Base Sequence↗
PubMed2002

Distribution of hantavirus foci in Belgium.

During 1999 and 2000, we performed rodent captures on 15 sites all over Belgium to evaluate the presence of hantaviruses in local rodent populations. Viral antibody and RNA detection was performed by ELISA/focus reduction neutralisation test and RT-PCR, respectively. We found hantavirus-positive rodents on 13 out of 15 trapping sites and 3 rodent species were found positive for hantavirus infection. Apart from Puumala virus that was carried by Clethrionomys glareolus, 2 additional rodent species, Microtus arvalis and Apodemus sylvaticus, were found antibody- and/or RNA-positive.

Animals↗
PubMed2001

Persistent infection is a rare sequel following infection of pigs with swine vesicular disease virus.

Nine isolates from pigs persistently infected with a recent Italian isolate of swine vesicular disease (SVD) virus, ITL/9/93, were collected sequentially over 121 days and were characterized antigenically and biochemically. There was an accumulation of amino acid (aa) substitutions in the capsid proteins throughout the carrier state that could be correlated with alterations in antigenicity in virus isolates collected late stage in infection. The aa substitutions detected mainly occurred in VPI and antigenic changes were detected in late isolates both at antigenic site 1, resulting in loss of binding of Mab 4GO7, and at a closely located site which has not yet been named, recognized by Mab C29. In further experiments groups of pigs were exposed to a range of SVD viruses, but no virus was isolated beyond 16 days post infection (dpi) nor viral RNA detected beyond 42 dpi. Attempts to transfer infection to sentinel pigs introduced some time after initial infection of the original pigs were largely unsuccessful. The carrier state was established in only one out of five experimental infections of pigs with SVD virus and can therefore be considered a rare sequel toinfection with SVD virus and is of limited significance in the epidemiology of the disease.

Amino Acid Sequence↗
PubMed2003

New reverse transcription-PCR assay for rapid and sensitive detection of enterovirus genomes in cerebrospinal fluid specimens of patients with aseptic meningitis.

Enterovirus (EV) detection by a new commercially available reverse transcription (RT)-PCR assay (Penter RT-PCR test) was compared with EV isolation from cell cultures and with EV detection by an in-house RT-PCR assay. Of the 54 cerebrospinal fluid specimens collected during a summer outbreak of aseptic meningitis, 52% were positive by cell culture versus 76% by in-house RT-PCR assay and 80% by the new RT-PCR test (52 versus 76 versus 80%; P = 0.003). This new reliable EV RNA detection test is suitable for clinical diagnosis of EV-related meningitis and may improve the management of EV-related neurological syndromes.

Cerebrospinal Fluid↗
PubMed1997

Determination of HCV RNA concentration by direct quantitation of the products from a single RT-PCR.

A novel method for the estimation of HCV RNA levels in vivo was developed, based on competitive RT-PCR. The use of the Tth DNA polymerase and 5' 32P-labeled antisense primer respectively reduced cross-contamination and permitted the direct quantification of viral loads by the analysis of the radioactivity of PCR products derived from a clinical sample and a competitive deleted template, separated previously on a polyacrilamide gel. A HCV fragment (H) and a competitive (deltaH) RNA templates were synthesized for optimizing the method. The minimal starting RNA detectable by RT-PCR was 40 copies. RT-PCR performed with ratios deltaH/H ranging from 1/1 to 1/20 revealed different relative percentages of both H and deltaH products, changing from 90% of deltaH product when the ratio was 1/1 to 5%, when it was 1/20. Regression analysis was adjusted to a linear model and served to further estimate HCV RNA loads from clinical samples. HCV RNA quantitation was carried out in 19 patients. Higher viral loads were related to type 1b infection and persistence of HCV RNA after interferon therapy. This method is simple, reproducible and useful for rapid estimation of HCV RNA load in vivo.

Antiviral Agents↗
PubMed1999

Detection of spring viremia of carp virus isolates by hybridization with non-radioactive probes and amplification by polymerase chain reaction.

For detection of spring viremia of carp virus (SVCV) DNA probes have been constructed using the reverse transcription-polymerase chain reaction (RT-PCR) amplification technique and cDNA cloning in plasmid and phage vectors. The specific primers for amplification of SVCV M and G genes were chosen and synthesized. Studies were carried out to establish the sensitivity and specificity of viral RNA detection in infected cell culture and pathogenic material from fish by the use of non-radioactive probes and RT-PCR. The efficiency of amplification with primers, complementary to the genome of the reference Fijan strain, was estimated in RT-PCR experiments with two SVCV strains. Under the same conditions, the quantity of PCR products amplified from the M2 strain was less than that from the ZL4 strain, which implies that the latter is more similar to the reference European SVCV Fijan isolate. Using DNA probes and dot-blot hybridization, SVCV was tested in samples taken from different organs of artificially infected carp with clinical signs of acute disease. The virus could be detected most reliably in fish brain. In most cases the hybridization signal was positive with samples having a viral titer of not less than 10(5) TCID50/g.

Animals↗
PubMed2003

Experimental infection of California birds with western equine encephalomyelitis and St. Louis encephalitis viruses.

A total of 27 bird species from the San Joaquin and Coachella valleys of California were inoculated subcutaneously with sympatric strains of western equine encephalomyelitis (WEE) and St. Louis encephalitis (SLE) viruses. Overall, 133 of 164 birds inoculated with WEE virus developed a viremia detected by plaque assay; significantly greater than 72 of 163 birds inoculated with SLE virus. Host competence was calculated as the average number of days that each avian species had a viremia > or = 2 log10 plaque-forming units per 0.1 ml, the threshold for infecting susceptible Culex tarsalis Coquillett, the primary vector of these viruses in California. Eleven of 20 species inoculated with WEE virus had a value > or = 1 and were considered to be competent hosts, whereas only six of 22 species inoculated with SLE virus had a value > or = 1. Overall, 133 of 164 birds inoculated with WEE virus and 105 of 163 inoculated with SLE virus produced antibody detectable by enzyme immunoassay and/or plaque reduction neutralization test. Six birds infected with WEE virus (one house finch, three mourning doves, one Brewer's sparrow, and one white-crowned sparrow) and nine birds infected with SLE virus (two house finches, three white-crowned sparrows, one song sparrow, two Western scrub-jays, and one orange crowned warbler) contained viral RNA detected by reverse transcription-polymerase chain reaction at necropsy > 6 wk postinoculation; infectious WEE and SLE viruses were only recovered from three mourning doves and an orange-crowned warbler, respectively, after blind passage in mosquito cells. Our study indicated that birds with elevated field antibody prevalence rates may not be the most competent hosts for encephalitis viruses and that relatively few birds developed chronic infections that could be important in virus persistence and dispersal.

Animals↗
PubMed1992

Regulation of the expression of ICAM-1 on human monocytes and monocytic tumor cell lines.

In this study we investigated the mechanisms regulating expression of ICAM-1 that plays an important role for Ag presentation, on peripheral blood monocytes, and three myelomonocytic cell lines representing different stages of monocyte maturation. ICAM-1 expression on freshly isolated monocytes was low in all donors tested. After 16- to 20-h incubation, about a 20-fold increase was observed, whereas ICAM-1 expression on lymphocytes did not change. This marked increase in Ag expression was specific for ICAM-1, because expression of other monocyte Ag remained unchanged (alpha-chain of lymphocyte function-associated Ag-1) or decreased (ICAM-2, alpha-chains of CR3 and CR4, their common beta-chain and Fc gamma RI) during overnight incubation; only HLA-DR showed a slight increase. Enhanced expression of ICAM-1 was not caused by adherence; it was also not due to trace amounts of IFN-gamma possibly present under our culture conditions. Endotoxin contamination of the medium was excluded as a cause for the enhanced expression, and neither LPS nor its antagonist polymyxin B were able to alter ICAM-1 expression. Whole blood culture almost completely prevented up-regulation of ICAM-1 expression, thus apparently mimicking the in vivo situation. Culture of monocytes together with other PBMC had no significant influence on monocyte ICAM-1 levels. From 12 different cytokines tested for their ability to modulate "spontaneous" up-regulation of ICAM-1 in culture, only IFN-gamma was found to increase expression about twofold. This effect was also observed in whole blood culture. All other cytokines had no significant effect. In contrast, ICAM-1 expression on two of the three cell lines (KG1 and HL60) was inducible by TNF-alpha to a much higher degree than by IFN-gamma, whereas the results with U937 were comparable with those obtained for normal monocytes. The protein- and RNA-synthesis inhibitors cycloheximide and actinomycin D prevented expression of ICAM-1 in a dose-dependent fashion. In Northern blot experiments no difference in the amounts of mRNA was observed between freshly isolated and cultured monocytes, indicating that "spontaneous" induction of ICAM-1 is regulated at a posttranscriptional level. In contrast, stimulation with IFN-gamma caused a significant increase of detectable RNA comparable to that observed for Ag expression. These results disclose a very special regulation of ICAM-1 expression on monocytes which could be consistent with the view that ICAM-1 is actively down-regulated in vivo until the monocyte leaves the circulation.

Antigens, CD↗