Immunologic aspects of characteristics, diagnosis, and treatment of coronavirus disease 2019 (COVID-19).

On March 11, 2020, the World Health Organization declared the worldwide spread of the infectious disease COVID-19, caused by a new strain of coronavirus, SARS-CoV-2, as a pandemic. Like in all other infectious diseases, the host immune system plays a key role in our defense against SARS-CoV-2 infection. However, viruses are able to evade the immune attack and proliferate and, in susceptible individuals, cause severe inflammatory response known as cytokine storm, particularly in the lungs. The advancement in our understanding of the mechanisms underlying the host immune responses promises to facilitate the development of approaches for prevention or treatment of diseases. Components of immune system, such as antibodies, can also be used to develop sensitive and specific diagnostic methods as well as novel therapeutic agents. In this review, we summarize our knowledge about how the host mounts immune responses to infection by SARS-CoV-2. We also describe the diagnostic methods being used for COVID-19 identification and summarize the current status of various therapeutic strategies, including vaccination, being considered for treatment of the disease.

Modulation of Glucagon-like Peptide-1 (GLP-1) Potency by Endocannabinoid-like Lipids Represents a Novel Mode of Regulating GLP-1 Receptor Signaling.

Glucagon-like peptide-1 (GLP-1) analogs are approved for treatment of type 2 diabetes and are in clinical trials for disorders including neurodegenerative diseases. GLP-1 receptor (GLP-1R) is expressed in many peripheral and neuronal tissues and is activated by circulating GLP-1. Other than food intake, little is known about factors regulating GLP-1 secretion. Given a normally basal circulating level of GLP-1, knowledge of mechanisms regulating GLP-1R signaling, which has diverse functions in extrapancreatic tissues, remains elusive. In this study, we found that the potency of GLP-1, not exendin 4, is specifically enhanced by the endocannabinoid-like lipids oleoylethanolamide (OEA) and 2-oleoylglycerol but not by stearoylethanolamide (SEA) or palmitoylethanolamide. 9.2 µM OEA enhances the potency of GLP-1 in stimulating cAMP production by 10-fold but does not affect its receptor binding affinity. OEA and 2-oleoylglycerol, but not SEA, bind to GLP-1 in a dose-dependent and saturable manner. OEA but not SEA promoted GLP-1(7-36) amide to trypsin inactivation in a dose-dependent and saturable manner. Susceptibility of GLP-1(7-36) amide to trypsin inactivation is increased 40-fold upon binding to OEA but not to SEA. Our findings indicate that OEA binds to GLP-1(7-36) amide and enhances the potency that may result from a conformational change of the peptide. In conclusion, modulating potency of GLP-1 by physiologically regulated endocannabinoid-like lipids allows GLP-1R signaling to be regulated spatiotemporally at a constant basal GLP-1 level.

Annexin II binds to capsid protein VP1 of enterovirus 71 and enhances viral infectivity.

Enterovirus type 71 (EV71) causes hand, foot, and mouth disease (HFMD), which is mostly self-limited but may be complicated with a severe to fatal neurological syndrome in some children. Understanding the molecular basis of virus-host interactions might help clarify the largely unknown neuropathogenic mechanisms of EV71. In this study, we showed that human annexin II (Anx2) protein could bind to the EV71 virion via the capsid protein VP1. Either pretreatment of EV71 with soluble recombinant Anx2 or pretreatment of host cells with an anti-Anx2 antibody could result in reduced viral attachment to the cell surface and a reduction of the subsequent virus yield in vitro. HepG2 cells, which do not express Anx2, remained permissive to EV71 infection, though the virus yield was lower than that for a cognate lineage expressing Anx2. Stable transfection of plasmids expressing Anx2 protein into HepG2 cells (HepG2-Anx2 cells) could enhance EV71 infectivity, with an increased virus yield, especially at a low infective dose, and the enhanced infectivity could be reversed by pretreating HepG2-Anx2 cells with an anti-Anx2 antibody. The Anx2-interacting domain was mapped by yeast two-hybrid analysis to VP1 amino acids 40 to 100, a region different from the known receptor binding domain on the surface of the picornavirus virion. Our data suggest that binding of EV71 to Anx2 on the cell surface can enhance viral entry and infectivity, especially at a low infective dose.

Impact of prior infection and repeated vaccination on post-vaccination antibody titers of the influenza A(H1N1)pdm09 strain in Taiwan schoolchildren: Implications for public health.

BACKGROUND: The objective of this study was to evaluate the effects of prior-infection and repeated vaccination on post-vaccination antibody titers. METHODS: A(H1N1)pdm09 strain was included in 2009 pandemic monovalent, 2010-2011, and 2011-2012 trivalent influenza vaccines (MIVpdm09, TIV10/11, TIV11/12) in Taiwan. During the 2011-2012 influenza season, we conducted a prospective sero-epidemiological cohort study among schoolchildren from grades 1 - 6 in the two elementary schools in Taipei with documented A(H1N1)pdm09 vaccination records since 2009. Serum samples were collected at pre-vaccination, 1-month, and 4-months post-vaccination (T1, T2, T3). Anti-A(H1N1)pdm09 hemagglutination inhibition titers (HI-Ab-titers) were examined. We also investigated the impact of four vaccination histories [(1) no previous vaccination (None), (2) vaccinated in 2009-2010 season (09v), (3) vaccinated in 2010-2011 season (10v), and (4) vaccinated consecutively in 2009-2010 and 2010-2011 seasons (09v + 10v)] and pre-vaccination HI-Ab levels on post-vaccination HI-Ab responses as well as adjusted vaccine effectiveness (aVE) against serologically-defined infection from T2 to T3. RESULTS: TIV11/12 had zero serious adverse events reported. A(H1N1)pdm09 strain in TIV11/12 elicited seroprotective Ab-titers in 98% of children and showed promising protection (aVE: 70.3% [95% confidence interval (CI): 51.0-82.1%]). Previously unvaccinated but infected children had a 3.96 times higher T2 geometric mean titer (T2-GMT) of HI-Ab than those naïve to A(H1N1)pdm09 (GMT [95% CI]: 1039.7[585.3-1845.9] vs. 262.5[65.9-1045], p = 0.046). Previously vaccinated children with seroprotective T1-Ab-titers had a higher T2-GMT and a greater aVE than those with non-seroprotective T1-Ab-titers. Repeatedly vaccinated children had lower T2-GMT than those receiving primary doses of TIV11/12. However, after controlling prior infection and T1-Ab-titers, differences in T2-GMT among the four vaccination histories became insignificant (p = 0.16). CONCLUSION: This study supports the implementation of annual mass-vaccination with A(H1N1)pdm09 in schoolchildren for three consecutive influenza seasons when vaccine and circulating strains were well matched, and found that prior infection and pre-vaccination HI-Ab levels positively impacted post-vaccination HI-Ab responses.

Candidate genes associated with susceptibility for SARS-coronavirus.

Assuming that no human had any previously acquired immunoprotection against severe acute respiratory syndrome coronavirus (SARS-CoV) during the 2003 SARS outbreak, the biological bases for possible difference in individual susceptibility are intriguing. However, this issue has never been fully elucidated. Based on the premise that SARS patients belonging to a given genotype group having a significantly higher SARS infection rate than others would imply that genotype group being more susceptible, we make use of a compartmental model describing disease transmission dynamics and clinical and gene data of 100 laboratory confirmed SARS patients from Chinese Han population in Taiwan to estimate the infection rates of distinct candidate genotype groups among these SARS-infected individuals. The results show that CXCL10(-938AA) is always protective whenever it appears, but appears rarely and only jointly with either Fgl2(+158T/*) or HO-1(-497A/*), while (Fgl2)(+158T/*) is associated with higher susceptibility unless combined with CXCL10/IP-10(-938AA), when jointly is associated with lower susceptibility. The novel modeling approach proposed, which does not require sizable case and control gene datasets, could have important future public health implications in swiftly identifying potential high-risk groups associated with being highly susceptible to a particular infectious disease.

Heat shock protein A1B 1267 polymorphism is highly associated with risk and prognosis of hepatocellular carcinoma: a case-control study.

We conducted a case-control study to elucidate the role of heat shock protein A1B (HSPA1B) 1267 single nucleotide polymorphism (SNP) on the risk and prognosis of hepatocellular carcinoma (HCC). Subjects enrolled included 150 pairs of sex- and age-matched HCC patients and unrelated controls. Genomic DNA was typed for HSPA1B1267 SNP using polymerase chain reaction with restriction fragment length polymorphism. The frequencies of the HSPA1B P2/P2 genotype and the HSPA1B P2 allele in HCC patients were higher than in unrelated controls (each p = 0.0001). Multivariate analysis identified the following independent risk factors for HCC: HSPA1B P1/P2 genotype (odds ratio [OR], 2.34; 95% confidence interval [CI], 1.07-5.11), HSPA1B P2/P2 genotype (OR, 12.06; 95% CI, 4.43-32.79), hepatitis B surface antigen (HBsAg) (OR, 25.95; 95% CI, 11.88-56.68), and antibodies to hepatitis C virus (anti-HCV) (OR, 70.43; 95% CI, 21.89-226.64). There was an additive interaction between HSPA1B P2 allele carriers and the presence of either HBsAg (synergy index = 2.48) or anti-HCV (synergy index = 1.52). However, as HSPA1B1267 SNP is a silent mutation, it is a surrogate genetic marker for increasing risk of HCC. Our findings indicate that patients with chronic hepatitis B/hepatitis C virus infection who harbor this SNP represent a high-risk group for HCC. They should receive more intensive surveillance for early detection of HCC. Moreover, patients with the HSPA1B P2 allele had significantly longer survival (p = 0.002).The limitations of this study include the unknown functional significance of the HSPA1B1267 polymorphism, the relatively small sample size, the fact that this was not a prospective study of cases and controls, and the questionable generalizability of the findings given the specific ethnic composition of the population studied.

Neuroprotective and mechanistic study of GJ-4 on okadaic acid-induced memory impairment in mice / 药学学报

GJ-4 is crocin enrichments extracted from Gardenia jasminoides J. Ellis, and our previous studies have shown that GJ-4 significantly improved learning and memory impairment induced by Aβ in mice. Herein, a memory deficit model was developed by injecting okadaic acid (OA) into the lateral ventricle of mice, and the neuroprotection and underlying mechanism of GJ-4 on neuronal injury caused by Tau hyperphosphorylation were investigated. The Animal Care & Welfare Committee, Institute of Materia Medica, CAMS & PUMC has approved all procedures (No.00000318). GJ-4 at different doses was intragastric administration to mice for 16 days. Step-down test and Morris water maze test showed that GJ-4 could significantly improve OA-induced memory impairment in mice, and reduced the loss of Nissl bodies in the hippocampus of mice. GJ-4 could also decrease the phosphorylation level of Tau protein at Ser396, Thr231 and Ser404 via increasing protein phosphatase 2A (PP2A) activity and inhibiting glycogen synthase kinase-3β (GSK-3β) activity. Besides, further researches indicated that GJ-4 could inhibit the level of oxidative stress in the brain of OA mice, reduce neuronal apoptosis and inhibit the neuroinflammation mediated by activation of astrocytes in the hippocampus of mice, and eventually achieve its effects in improving learning and memory impairment in mice. According to these findings, we anticipated that GJ-4 might be a potential therapeutic drug for Alzheimer's disease.

A Health Education Program for Home Emergency Management of Acute Complications of Diabetes in the Elderly / 中国医学科学院学报

Objective To establish a health education program for home emergency management of acute complications of diabetes in the elderly.Methods The program was drafted by literature review and panel discussion.The final draft was formed after two rounds of correspondence from 13 experts.Results The recovery rate of the two rounds of expert correspondence was 100%,and the expert authority coefficient was 0.98.The Kendall's harmony coefficients of the two rounds of correspondence were 0.263 and 0.212 respectively(both P<0.001).The established health education program included indicators of three categories:early stage of acute complications of diabetes at home(understanding the inducing factors),emergency warning(quick and early identification in case of emergency),and emergency treatment at home.Conclusion The contents of the health education program are systematic and reliable and meet the needs of health education for home emergency management of the elderly with diabetes.

Effects of Decitabine Combined with Anlotinib on Proliferation and Apoptosis of Multiple Myeloma Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the biological effects and its relative mechanism of decitabine combined with anlotinib on multiple myeloma cells.@*METHODS@#The human MM cell lines and primary cells were treated with different concentrations of decitabine, anlotinib, and decitabine+anlotinib, respectively. The cell viability was detected and combination effect was calculated by CCK-8 assay. The apoptosis rate was measured by flow cytometry and the level of c-Myc protein was determined by Western blot.@*RESULTS@#Both decitabine and anlotinib could effectively inhibit the proliferation and induce the apoptosis of MM cell lines NCI-H929 and RPMI-8226. The effect of combined treatment on the inhibition of cell proliferation and induction of apoptosis was stronger than that of single-drug treatment. The combination of the two drugs also showed strong cytotoxicity in primary MM cells. Decitabine and anlotinib could down-regulate the level of c-Myc protein in MM cells and the c-Myc level in the combination group was the lowest.@*CONCLUSION@#Decitabine combined with anlotinib can effectively inhibit the proliferation and induce apoptosis of MM cells, which provides a certain experimental basis for the treatment of human MM.

Challenges faced by hospital healthcare workers in using a syndrome-based surveillance system during the 2003 outbreak of severe acute respiratory syndrome in Taiwan.

Because the severe acute respiratory syndrome (SARS) outbreak in Taiwan in 2003 was worsened by hospital infections, we analyzed 229 questionnaires (84.8% of 270 sent) completed by surveyed healthcare workers who cared for patients with SARS in 3 types of hospitals, to identify surveillance problems. Atypical clinical presentation was the most often reported problem, regardless of hospital type, which strongly indicates that more timely syndromic surveillance was needed.

[Clinical study on "Jin's three-needling" in treatment of generalized anxiety disorder].

OBJECTIVE: To study the clinical effect of "Jin's three-needling" in the treatment of generalized anxiety disorder. METHODS: Fifty-eight patients with generalized anxiety were randomly assigned to two groups equally, the medication group treated with anti-anxiety drugs and the acupuncture group with "Jin's three-needling". The treatment course was 6 weeks. The clinical effects were evaluated with Hamilton anxiety scale (HAMA), clinical global impression (CGI), and treatment emergent symptom scale (TESS) before treatment and at the end of 2nd, 4th, 6th week of the treatment course. The concentration of 5-hydroxytryptamine (5-HT) in platelet, and plasma levels of corticosterone (CS) and adrenocorticotropic hormone (ACTH) were measured with high performance liquid chromatography-electrochemical detection (HPLC-ED) method before and after treatment. RESULTS: The clinical effects in the two groups were equivalent, while the adverse reaction found in the acupuncture group was less than that in the medication group (P < 0.05). The platelet concentration of 5-HT and plasma ACTH level decreased significantly in both groups after treatment with insignificant difference between the group (P < 0.05). The plasma CS level had no obvious change in the two groups after treatment as compared with that before treatment respectively. CONCLUSION: "Jin's three-needling" shows similar curative effect on generalized anxiety to routine Western medicine but with less adverse reaction, which may be realized through regulating the platelet 5-HT concentration and plasma ACTH level.

The Effects of Decitabine Combined with All-Trans Retinoic Acid on the Number of Immune Cells in Myeloid Neoplasms / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of decitabine (DEC) combined with all-trans retinoic acid (ATRA) on the number of immune cells, efficacy and adverse reactions in the treatment of myeloid neoplasms patients.@*METHODS@#Eighty-four patients with myeloid tumors, including AML, MDS-EB-1 or MDS-EB-2 treated by the regimen containing decitabine in our hospital from January 2009 to October 2019 were enrolled and retrospectively analyzed, among the patients, 21 patients treated with DEC alone, 24 patients treated with DEC combined with ATRA (DEC/ATRA) and 39 patients treated with DEC combined with G-CSF priming regimen (DEC/priming). The changes of peripheral blood immune cell levels before and after treatment of the patients between the three groups were compared, and the differences in clinical efficacy and adverse reactions of the patients between the three groups were also compared.@*RESULTS@#There was no statistical differences in the number of immune cells among the patients in the three groups before treatment (P>0.05). NK cell levels decreased significantly in the patients in DEC and DEC/ATRA group after treatment (P<0.05); After treatment, the levels of CD8+ and CD3+T cells in the patients treated by DEC /priming regimen significantly increased (P<0.05), while the levels of CD3-HLA-DR+ B cells significantly decreased (P<0.05). The overall response rate (ORR) of the patients in DEC/ATRA group (75%) and DEC/priming group (74.36%) was significantly higher than 42.86% in DEC monotherapy group, and the differences showed statistically significant (P<0.05), while the ORR between the patients in DEC/ATRA and DEC/priming group showed no statistic differences (P>0.05). There were no statistical differences in overall survival (OS) and incidence of bleeding between the patients in the three groups (P>0.05). The incidences of grade 3 to 4 bone marrow suppression and the infection rate of the patients in DEC monotherapy and DEC/ATRA group were significantly lower than that in DEC/priming regimen group after treatment (all P<0.05), however, there was no statistical difference between DEC monotherapy and the DEC/ATRA group.@*CONCLUSION@#The efficacy of DEC/ATRA on myeloid neoplasms is comparable to that of DEC/priming regimen, and the anti-myeloid tumor effect of DEC/ATRA regimen may be related to the regulation of NK cells and T cells.

Design of microarray probes for virus identification and detection of emerging viruses at the genus level.

BACKGROUND: Most virus detection methods are geared towards the detection of specific single viruses or just a few known targets, and lack the capability to uncover the novel viruses that cause emerging viral infections. To address this issue, we developed a computational method that identifies the conserved viral sequences at the genus level for all viral genomes available in GenBank, and established a virus probe library. The virus probes are used not only to identify known viruses but also for discerning the genera of emerging or uncharacterized ones. RESULTS: Using the microarray approach, the identity of the virus in a test sample is determined by the signals of both genus and species-specific probes. The genera of emerging and uncharacterized viruses are determined based on hybridization of the viral sequences to the conserved probes for the existing viral genera. A detection and classification procedure to determine the identity of a virus directly from detection signals results in the rapid identification of the virus. CONCLUSION: We have demonstrated the validity and feasibility of the above strategy with a small number of viral samples. The probe design algorithm can be applied to any publicly available viral sequence database. The strategy of using separate genus and species probe sets enables the use of a straightforward virus identity calculation directly based on the hybridization signals. Our virus identification strategy has great potential in the diagnosis of viral infections. The virus genus and specific probe database and the associated summary tables are available at http://genestamp.sinica.edu.tw/virus/index.htm.

Nasopharyngeal shedding of severe acute respiratory syndrome-associated coronavirus is associated with genetic polymorphisms.

BACKGROUND: A high initial or peak severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) load in nasopharyngeal specimens was shown to be associated with a high mortality rate. Because all infected individuals were devoid of preeexisting protective immunity against SARS-CoV, the biological basis for the variable virus burdens in different patients remains elusive. METHODS: The nationwide SARS database in Taiwan was analyzed, and genotyping of 281 single-nucleotide polymorphisms (SNPs) of 65 genes was performed for 94 patients with SARS, to identify SNPs for which distribution between patients with or without detectable nasopharyngeal shedding of SARS-CoV was biased. RESULTS: Titers of SARS-CoV shed in nasopharyngeal specimens varied widely, ranging from nondetectable to 10(8) SARS-CoV RNA copies/mL, and they were correlated positively with a high mortality rate (P<.0001, by trend test) and with early death (i.e., death occurring within 2 weeks of the onset of illness) (P=.0015, by trend test). Virus shedding was found to be higher among male patients (P=.0014, by multivariate logistic regression) and among older patients (P=.015, by multivariate logistic regression). Detectable nasopharyngeal shedding of SARS-CoV was associated with polymorphic alleles of interleukins 18 (P=.014) and 1A (P=.031) and a member of NF kappa B complex (reticuloendotheliosis viral oncogene homolog B [RelB]) (P=.034), all of which are proinflammatory in nature, as well as the procoagulation molecule fibrinogen-like protein 2 (P=.008). CONCLUSION: The SARS-CoV load is a determinant of clinical outcomes of SARS, and it is associated with polymorphisms of genes involved in innate immunity, which might be regulated in an age- and sex-dependent manner. The findings of the present study provided leads to genes involved in the host response to SARS-CoV infection; if substantiated with functional studies, these findings may be applicable to other newly emerged respiratory viruses (e.g., the influenza pandemic strain).

Study of IgG subclass profiles of anti-HBs in populations with different HBV infection status.

To study IgG-specific subclasses of hepatitis B virus (HBV) surface antigen (anti-HBs), in different populations in Taiwan, a comparison was made between 104 chronic carriers (60 male and 44 female) and 439 recovered individuals (247 male and 192 female). Biochemical analyses of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were also performed. Among the 104 chronic carriers, 21 patients had abnormal ALT and AST levels (> 25 IU/ml). When comparing the patients with abnormal ALT and AST levels to chronic carriers with normal ALT and AST levels, no statistical difference was observed for anti-HBs levels (p > 0.05). The IgG subclass pattern of the relative anti-HBs IgG subclass titers was IgG1 > IgG3 = IgG4 in both chronic carriers and recovered individuals (p < 0.05). IgG1 is the predominant anti-HBs antibody after HBV infection, in either chronic carriers or in HBV-cured individuals. This finding is partly inconsistent with data reported from other group who suggested in individuals naturally infected, the anti-HBs IgG consists mainly of IgG3 and IgG1. In contrast to that of our previous studies of anti-HBe and anti-HBc, the mean OD values of anti-HBs total IgG, and all IgG subclasses except for IgG2, of either males or females, were significantly higher in recovered individuals than in chronic carriers, while the mean OD values of anti-HBe and anti-HBc were significantly higher in chronic carriers than in recovered individuals (P < 0.05). The IgG subclass profile of anti-HBs in chronic carriers was not changed with liver inflammation and was independent of sex and age, except in individuals with abnormal ALT and AST for whom anti-HBs IgG1 was not significantly higher than IgG3 (p > 0.05), in spite of that whose mean O.D. value is higher.

Expression, purification and characterization of enterovirus-71 virus-like particles.

AIM: Enterovirus 71 (EV71) has been implicated as the etiological agent responsible for the recent outbreaks of hand, foot and mouth disease associated with severe neurological diseases in the Asia-Pacific region. METHODS: The assembly process was hypothesized to occur via an orchestrated proteolytic processing of the P1 precursor by the viral protease 3CD. To test this hypothesis, we constructed 3 recombinant baculoviruses: Bac-P1 expressing P1; Bac-3CD expressing 3CD; and Bac-P1-3CD co-expressing P1 and 3CD. RESULTS: Both single infection by Bac-P1-3CD and co-infection by Bac-P1 and Bac-3CD resulted in correct cleavage of P1 to yield individual proteins VP0, VP1 and VP3, while the former approach yielded higher VLP production. In the cells, the structural proteins self-assembled into clusters of virus-like particles (VLP) resembling the authentic EV71 particle aggregates. After ultracentrifugation purification, the dispersed VLPs were indistinguishable from the authentic virus in size, appearance, composition and surface epitopes, as determined by SDS-PAGE, Western blot, transmission electron microscopy and immunogold labeling. CONCLUSION: Our data, for the first time, suggest that in insect cells EV71 structural proteins adopt a processing and assembly pathway similar to poliovirus assembly. The preservation of particle morphology and composition suggest that the VLP may be a valuable vaccine candidate to prevent EV71 epidemics.

The lesson of supplementary treatment with Chinese medicine on severe laboratory-confirmed SARS patients.

Chinese medicine (CM) has been used to control infectious diseases for thousands of years. In 2003 outbreaks of severe acute respiratory syndrome (SARS) occurred in China, Hong Kong and Taiwan. In view of the possible beneficial effect of CM on SARS, we conducted this study to examine whether CM is of any benefit as a supplementary treatment of SARS. Four severe laboratory-confirmed SARS patients received routine western-medicine treatment plus different supplementary treatment: CM A, CM B and CM C (placebo control). We reported the course of the cases in terms of changes in chest radiographic scores. Case 1 treated as a placebo control passed away on the 9th day after onset of disease. The other three cases treated with CM A or CM B survived. The initial findings seemed to indicate a favorable effect of CM on management of SARS. The findings need to be verified with a larger sample. Using CM as a supplementary treatment of severe SARS seems to indicate that natural herbal medicine can be used against avian influenza. Hence, such related experience or clinical trials should be taken into consideration when facing the possible outbreak of avian influenza in the future.

The study of IgG subclass profiles of anti-hbc in populations with different status of HBV infection.

To study IgG subclasses for the hepatitis B virus (HBV) core antigen (anti-HBc) in different populations, a comparison was made between 104 chronic carriers (60 male and 44 female) and 434 recovered individuals (247 male and 192 female). Biochemistry analyses of AST (aspartate aminotransferase) and ALT (alanine aminotransferase) were also performed. Among the 104 chronic carriers, 21 patients were found to be ALT and AST abnormal (> 25 IU/ml). After comparing these ALT and AST abnormal patients with other ALT and AST normal chronic carriers, no statistical difference was observed in the OD values of the anti-HBe (p > 0.05). The ELISA results showed the anti-HBc IgG subclass pattern was IgG1 > IgG3 > IgG4 in chronic carriers and IgG3 > IgG1 > IgG4 in recovered individuals (p < 0.05). This result suggests the IgG1/IgG3 ratio may be related with HBV status. However, in spite of the different anti-HBc IgG1/IgG3 patterns demonstrated in different populations, both anti-HBc IgG1 and IgG3 concentrations were significantly higher in chronic carriers (p < 0.05). Therefore, both the anti-HBc IgG1/IgG3 ratio and their amounts differed. They may play a significant role in chronic carriers and recovered individuals. The anti-HBc IgG subclass profiles of chronic carriers were not changed regardless of liver inflammation, and were independent of sex and age.

Severe acute respiratory syndrome coronavirus on hospital surfaces.

BACKGROUND: Health care workers continued to contract severe acute respiratory syndrome (SARS), even after barrier precautions were widely implemented. METHODS: We explored the possible contribution of contaminated hospital surfaces to SARS transmission by swabbing surfaces in 2 hospitals and testing the swab samples by reverse-transcriptase polymerase chain reaction (RT-PCR) and viral culture. RESULTS: Twenty-six of 94 swab samples tested positive for viral RNA. Swab samples of respiratory secretions from each of the 4 patients examined tested positive by RT-PCR, as were 12 of 43 swabs from patient rooms and 10 of 47 swabs from other parts of the hospital, including the computer mouses at 2 nursing stations and the handrail of the public elevator. Specimens from areas with patients with SARS in the most infectious phase of illness (days 5-15 after onset) were more likely to be RNA positive than were swab specimens from elsewhere (24 of 63 samples vs. 2 of 31 samples; P=.001). All cultures showed no growth. CONCLUSIONS: Although the viruses identified may have been noninfectious, health care workers should be aware that SARS coronavirus can contaminate environmental surfaces in the hospital, and fomites should be considered to be a possible mode of transmission of SARS.