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OBJECTIVES: There is conflicting data regarding the response of older people with HIV (PWH) to antiretroviral therapy (ART). The objective of this study was to evaluate the long-term immunological and virological responses, changes in regimen, and adverse drug reactions (ADRs) in older participants (50+ years) compared with younger (18-34âyears) and middle-aged (35-49âyears) PWH. METHODS: A retrospective review of medical records was conducted on 1622 participants who received ART in Yunnan Province, China, from 2010 to 2019. The study compared CD4+ T-cell counts, CD4+/CD8+ ratio, and relative numbers between different groups using the Kruskal-Wallis test. Cox proportional hazards regression models were used to identify variables associated with the occurrence of immune reconstitution insufficiency. The rates of immune reconstitution, incidence of ADRs, and rates of treatment change were analyzed using the chi-squared test or Fisher's exact test. RESULTS: Over 95% achieved viral load 200âcopies/ml or less, with no age-related difference. However, older participants exhibited significantly lower CD4+ T-cell counts and CD4+/CD8+ recovery post-ART (Pâ<â0.001), with only 32.21% achieving immune reconstitution (compared with young: 52.16%, middle-aged: 39.29%, Pâ<â0.001) at the end of follow-up. Middle-aged and elderly participants changed ART regimens more because of ADRs, especially bone marrow suppression and renal dysfunction. CONCLUSION: Although the virological response was consistent across age groups, older individuals showed poorer immune responses and higher susceptibility to side effects. This underscores the need for tailored interventions and comprehensive management for older patients with HIV.
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Fármacos Anti-HIV , Infecções por HIV , Pessoa de Meia-Idade , Idoso , Humanos , Infecções por HIV/tratamento farmacológico , Fármacos Anti-HIV/efeitos adversos , China , Resultado do Tratamento , Contagem de Linfócito CD4 , Carga ViralRESUMO
HIV-1CRF08_BC is the most prevalent epidemic subtype among heterosexual (HET) and intravenous drug users (IDUs) in Kunming, Yunnan. Using the pol region of gene sequences derived from molecular epidemiological surveys, we developed a molecular transmission network for the purpose of analyzing its epidemiological characteristics, assessing its epidemiological trends, identifying its potential transmission relationships, and developing targeted interventions. HyPhy 2.2.4 was used to calculate pairwise genetic distances between sequences; GraphPad-Prism 8.0 was employed to determine the standard genetic distance; and Cytoscope 3.7.2 was applied to visualize the network. We used the network analysis tools to investigate network characteristics and the Molecular Complex Detection (MCODE) tool to observe the growth of the network. We utilized a logistic regression model to examine the factors influencing clustering and a zero-inflated Poisson model to investigate the factors influencing potential transmission links. At the standard genetic distance threshold of 0.008, 406 out of 858 study participants were clustered in 132 dissemination networks with a total network linkage of 868, and the number of links per sequence ranged from 1 to 19. The MCODE analysis identified three significant modular clusters in the networks, with network scores ranging from 4.9 to 7. In models of logistic regression, HET, middle-aged and elderly individuals, and residents of northern and southeastern Kunming were more likely to enter the transmission network. According to the zero-inflated Poisson model, age, transmission category, sampling year, marital status, and CD4+ T level had a significant effect on the size of links. The molecular clusters in Kunming's molecular transmission network are specific and aggregate to a certain extent. HIV-1 molecular network analysis provided information on local transmission characteristics, and these findings helped to determine the priority of transmission-reduction interventions.
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In China, most SARS-CoV-2-infected individuals had been vaccinated with inactivated vaccines. However, little is known about their immune resistances to the previous variants of concerns (VOCs) and the current Omicron sublineages. Here, we collected convalescent serum samples from SARS-CoV-2-infected individuals during the ancestral, Delta, and Omicron BA.1 waves, and evaluated their cross-neutralizing antibodies (nAbs) against the previous VOCs and the current Omicron sublineages using VSV-based pseudoviruses. In the convalescents who had been unvaccinated and vaccinated with two doses of inactivated vaccines, we found infections from either the ancestral or the Delta strain elicited moderate cross-nAbs to previous VOCs, but very few cross-nAbs to the Omicron sublineages, including BA.1, BA.2, BA.3, and BA.4/5. The individuals who had been vaccinated with two doses of inactivated vaccines before Omicron BA.1 infection had moderate nAbs to Omicron BA.1, but weak cross-nAbs to the other Omicron sublineages. While three doses of inactivated vaccines followed Omicron BA.1 infection induced elevated and still weak cross-nAbs to other Omicron sublineages. Our results indicate that the Omicron sublineages show significant immune escape in the previously SARS-CoV-2-infected individuals and thus highlights the importance of vaccine boosters in this population.
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COVID-19 , SARS-CoV-2 , Humanos , Vacinas de Produtos Inativados , Soroterapia para COVID-19 , Anticorpos Neutralizantes , Anticorpos AntiviraisRESUMO
The emerging SARS-CoV-2 variants, commonly with many mutations in S1 subunit of spike (S) protein are weakening the efficacy of the current vaccines and antibody therapeutics. This calls for the variant-proof SARS-CoV-2 vaccines targeting the more conserved regions in S protein. Here, we designed a recombinant subunit vaccine, HR121, targeting the conserved HR1 domain in S2 subunit of S protein. HR121 consisting of HR1-linker1-HR2-linker2-HR1, is conformationally and functionally analogous to the HR1 domain present in the fusion intermediate conformation of S2 subunit. Immunization with HR121 in rabbits and rhesus macaques elicited highly potent cross-neutralizing antibodies against SARS-CoV-2 and its variants, particularly Omicron sublineages. Vaccination with HR121 achieved near-full protections against prototype SARS-CoV-2 infection in hACE2 transgenic mice, Syrian golden hamsters and rhesus macaques, and effective protection against Omicron BA.2 infection in Syrian golden hamsters. This study demonstrates that HR121 is a promising candidate of variant-proof SARS-CoV-2 vaccine with a novel conserved target in the S2 subunit for application against current and future SARS-CoV-2 variants.
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Vacinas contra COVID-19 , COVID-19 , Animais , Cricetinae , Camundongos , Humanos , Coelhos , SARS-CoV-2 , Macaca mulatta , Mesocricetus , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Camundongos Transgênicos , Anticorpos AntiviraisRESUMO
The continuously arising of SARS-CoV-2 variants has been posting a great threat to public health safety globally, from B.1.17 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.617.2 (Delta) to B.1.1.529 (Omicron). The emerging or re-emerging of the SARS-CoV-2 variants of concern is calling for the constant monitoring of their epidemics, pathogenicity and immune escape. In this study, we aimed to characterize replication and pathogenicity of the Alpha and Delta variant strains isolated from patients infected in Laos. The amino acid mutations within the spike fragment of the isolates were determined via sequencing. The more efficient replication of the Alpha and Delta isolates was documented than the prototyped SARS-CoV-2 in Calu-3 and Caco-2 âcells, while such features were not observed in Huh-7, Vero E6 and HPA-3 âcells. We utilized both animal models of human ACE2 (hACE2) transgenic mice and hamsters to evaluate the pathogenesis of the isolates. The Alpha and Delta can replicate well in multiple organs and cause moderate to severe lung pathology in these animals. In conclusion, the spike protein of the isolated Alpha and Delta variant strains was characterized, and the replication and pathogenicity of the strains in the cells and animal models were also evaluated.
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COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2 , Células CACO-2 , COVID-19/virologia , Camundongos Transgênicos , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus , VirulênciaRESUMO
Background: HIV viral load (VL) is an important indicator to monitor treatment response in antiretroviral therapy (ART). Patients on ART may experience viral blips, with low-level elevations of VL between 50 and 999 copies/mL known as low-level viraemia (LLV), but not reaching the threshold for virological failure (≥1,000 copies/mL) defined by WHO guidelines. The objective was to investigate the long-term impact of LLV on virological failure. Methods: We analyzed adults who were ART naïve at baseline. LLV was defined as having an VL of 51-999 copies/mL at least once. The subjects with LLV were grouped into three categories: 51-199, 200-399, and 400-999 copies/mL. Patients with multiple episodes of LLV were classified based on the highest VL result. The subjects with LLV were also grouped by the frequency of LLV, i.e., a single episode, two consecutive episodes, two intermittent episodes, more than two consecutive episodes, and more than two intermittent episodes. Multivariable Cox models were used to predict the association of LLV with virological failure. Results: A total of 93,944 subjects were included. The median number of VL tests performed was 3. There were 21,203 LLV cases, with an overall incidence of 22.6%. Most of the LLV cases were found in subjects with LVs of 50-199 copies/mL, followed by 400-999 and 200-399 copies/mL. Most of the LLV cases experienced single episodes, and the numbers of LLV with two consecutive episodes, two intermittent episodes, more than two consecutive episodes and more than two intermittent episodes were decreased successively. The risk factors associated with virological failure include: intermediate-level (200-399 copies/mL) and high-level (400-999 copies/mL) LLV, single episodes of LLV and two or more than two consecutive episodes of LLV, which may put the subjects at a 1.28-2.26-fold higher risk for virological failure. Conclusion: Strengthened immediate medical attention should be placed on patients with VL of 200-999 copies/mL. The patients having experienced LLV once should be targeted for case management and repeat VL testing within 24 weeks to determine persistent LLV and monitor virological failure.
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Infecções por HIV , HIV-1 , China , Genoma Viral , Genótipo , HIV-1/genética , Heterossexualidade , Humanos , Filogenia , Recombinação Genética , Análise de Sequência de DNARESUMO
Latent reservoir persistence remains a major obstacle for curing human immunodeficiency virus type 1 (HIV-1) infection. Thus, strategies for the elimination of latent HIV-1 are urgently needed. As a bromodomain and extra-terminal (BET) inhibitor, BMS-986158 has been used in clinical trials for advanced solid tumors and hematological malignancies. Here, we found that BMS-986158 reactivated latent HIV-1 in three types of HIV-1 latency cells in vitro, and in combination antiretroviral therapy (cART)-treated patient-derived peripheral blood mononuclear cells ex vivo, without influencing global immune cell activation. BMS-986158 reactivated latent HIV-1 by increasing phosphorylation of CDK9 at Thr186 and promoting recruitment of CDK9 and RNA polymerase II to the HIV-1 long terminal repeat in J-Lat cells. Furthermore, BMS-986158 exerted strong synergism in reactivating latent HIV-1 when combined with prostratin and vorinostat and enhanced the antiviral activity of anti-HIV-1 drugs. Finally, BMS-986158 showed antiviral activity in an HIV-1 acute infection model, possibly by arresting the cell cycle in infected cells. Thus, these results suggest that BMS-986158 is a potential candidate for AIDS/HIV-1 therapy.
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BACKGROUND: Yunnan has the highest rates of HIV in China. Other treatable sexually transmitted infections (STIs) are associated with accelerated HIV transmission and poor ART outcomes, but are only diagnosed by syndromic algorithms. METHODS: We recruited 406 HIV-positive participants for a cross-sectional study (204 ART-naive and 202 receiving ART). Blood samples and first-voided urine samples were collected. Real-time polymerase chain reaction methods were used for diagnosing Chlamydia trachomatis (CT), Neisseria gonorrhea (NG) and Mycoplasma genitalium (MG). Syphilis and herpes simplex virus type 2 (HSV-2) tests were also performed. RESULTS: Among the 406 participants, the overall prevalence of STIs was 47.0% and 45.1% in ART-naive individuals and 49.0% in individuals receiving ART, respectively. The testing frequencies were 11.6% (11.8% vs. 11.4%), 33.2% (29.4% vs. 37.1%), 3.2% (3.4% vs. 3.0%), 2.0% (3.4% vs. 0.5%) and 4.7% (6.4% vs. 3.0%) for active syphilis, HSV-2, CT, NG and MG, respectively. The percentage of multiple infections in both groups was 10.8% (22/204) in ART-naive participants and 9.9% (20/202) in participants receiving ART. Female sex, an age between 18 and 35 years, ever injecting drugs, homosexual or bisexual status, HIV/HBV coinfection, and not receiving ART were identified as risk factors. Self-reported asymptomatic patients were not eliminated from having a laboratory-diagnosed STI. CONCLUSIONS: The STI prevalence was 47.0% (45.1% vs. 49.0%), and HSV-2, syphilis and MG were the most common STIs in HIV-infected individuals. We found a high prevalence (6.4%) of MG in ART-naive individuals. HIV-positive individuals tend to neglect or hide their genital tract discomfort; thus, we suggest strengthening STI joint screening and treatment services among HIV-infected individuals regardless of whether they describe genital tract discomfort.
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Infecções por HIV/epidemiologia , Programas de Rastreamento/métodos , Medição de Risco/métodos , Infecções Sexualmente Transmissíveis/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
The succinate-acetate permease (SatP) is an anion channel with six transmembrane domains. It forms different oligomers, especially hexamers in the detergent as well as in the membrane. Solid-state NMR studies of SatP were carried out successfully on SatP complexes by reconstructing the protein into liposomes or retaining the protein in the native membrane of E. coli., where it was expressed. The comparison of 13C-13C 2D correlation spectra between the two samples showed great similarity, opening the possibility to further study the acetate transport mechanism of SatP in its native membrane environment. Solid-state NMR studies also revealed small chemical shift differences of SatP in the two different membrane systems, indicating the importance of the lipid environment in determining the membrane protein structures and dynamics. Combining different 2D SSNMR spectra, chemical shift assignments were made on some sites, consistent with the helical structures in the transmembrane domains. In the end, we pointed out the limitation in the sensitivity for membrane proteins with such a size, and also indicated possible ways to overcome it.
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New human immunodeficiency virus (HIV)-1 circulating recombinant forms (CRFs) have recently emerged and disseminated rapidly in China; in total 38 CRFs have been identified thus far. Yunnan province shares its border with Myanmar, and is regarded as a "hotspot" for the occurrence of new HIV-1 recombinations; more than half of novel CRFs reported in China have been first documented in Yunnan province. In the present study, based on the information available on four existing near-full-length genome (NFLG) sequences, combined with data on four other closely related sequences obtained via Basic Local Alignment Search Tool (BLAST) analysis, NFLG/subregion phylogenetic, bootscanning, and time to the most recent common ancestor (TMRCA) analyses were performed. Phylogenetic analysis revealed that the eight strains demonstrated the formation of a distinct monophyletic branch with a bootstrap value of 100%. Strains in this branch were distantly related to all known HIV-1 CRFs; it was temporarily named CRF111_01C. Bootscanning analysis revealed that CRF111_01C consisted of a CRF01_AE backbone and four inserted subtype C segments. Remarkably, CRF111_01C shared six mosaic fragment identities with the previously identified CRF100_01C. Furthermore, CRF111_01C may be deemed a potential second-generation CRF consisting of CRF100_01C and C. Coalescent Bayesian analyses revealed that the TMRCA of CRF111_01C was approximately the period 1999-2002. The emergence of such second-generation recombinants highlights that continuous molecular screening is necessary to carefully monitor the evolutionary dynamics of HIV-1 epidemics.
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Genoma Viral , HIV-1/genética , Recombinação Genética , China , Infecções por HIV/virologia , HIV-1/classificação , FilogeniaRESUMO
Because of the relatively limited understanding of coronavirus disease 2019 (COVID-19) pathogenesis, immunological analysis for vaccine development is needed. Mice and macaques were immunized with an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine prepared by two inactivators. Various immunological indexes were tested, and viral challenges were performed on day 7 or 150 after booster immunization in monkeys. This inactivated SARS-CoV-2 vaccine was produced by sequential inactivation with formaldehyde followed by propiolactone. The various antibody responses and specific T cell responses to different viral antigens elicited in immunized animals were maintained for longer than 150 days. This comprehensive immune response could effectively protect vaccinated macaques by inhibiting viral replication in macaques and substantially alleviating immunopathological damage, and no clinical manifestation of immunopathogenicity was observed in immunized individuals during viral challenge. This candidate inactivated vaccine was identified as being effective against SARS-CoV-2 challenge in rhesus macaques.
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BACKGROUND: Injecting drugs is associated with a high risk of HIV infection, alongside the risk of a drug overdose and mental health problems. OBJECTIVE: To evaluate the effect of methadone maintenance treatment (MMT) combined with rilpivirine (RPV)-based regimens on drug use of HIV individuals. METHODS: This study was a prospective, open-label, controlled, drug-drug interaction trial at a single center for 24 weeks. Participants on stable MMT were randomly divided into two groups administered RPV/TDF/3TC (RPV group) and EFV/TDF/3TC (EFV group), respectively. Adjustment doses of methadone were monitored for 12 weeks. HIV-1 RNA was used to evaluate the effects of antiretroviral therapy at week 24. Acute opioid withdrawal-, drug craving questionnaire- and MOSHIV scales were used to assess study outcomes. RESULTS: 22 and 18 cases of HIV-infected drug users were recruited in the RPV and EFV groups, respectively. Thirty-one cases had completed monitoring and clinical evaluation at week 24. In the RPV and EFV groups, 32% and 56% of the participants had methadone dose adjustment, respectively, indicating a significantly lower rate in the RPV group. The rates of individuals with HIV RNA levels from 50-500 copies/ml were 94% (RPV group) and 90% (EFV group). The drug craving questionnaire scale scores decreased in both groups. After one week of treatments, acute opioid withdrawal scale scores increased in both groups, with no significant difference between them. CONCLUSION: Concomitant administration of RPV does not significantly affect methadone and could decrease withdrawal symptoms. An RPV-based regimen may be used as first-line treatment in IDUs with HIV infection.
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Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Alcinos , Fármacos Anti-HIV/uso terapêutico , Benzoxazinas , Ciclopropanos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Metadona/uso terapêutico , Estudos Prospectivos , Rilpivirina/uso terapêutico , Carga ViralRESUMO
Human immunodeficiency virus (HIV) infection is associated with an increased risk of aggressive lymphoma, especially diffuse large B cell lymphoma (DLBCL). There are few data regarding HIV-associated DLBCL in China. Therefore, we analyzed the characteristics and outcomes of patients with HIV-associated DLBCL from our center. We retrospectively studied HIV-infected patients with DLBCL from 2011 to 2019. Data on HIV infection and lymphoma characteristics, treatments and outcomes were retrieved and analyzed. In 78 patients with HIV-associated DLBCL, most had poor performance status (PS) (74%), elevated lactate dehydrogenase (LDH) levels (95%), B symptoms (74%), advanced Ann Arbor stages (81%), bulky diseases (64%) and extranodal involvement (70%) at diagnosis. The median CD4+ T cell count was 162/µl, and 26 patients were already on combination antiretroviral therapy (cART) treatment at diagnosis of DLBCL. Elevated whole blood EBV DNA copy number was detected in 38 patients (66%, 38/58). Of the 45 patients evaluated at the end of treatment, 26 (58%) achieved CR, 6 (13%) achieved PR and 6 (13%) experienced progressive disease. The 2-year progression-free survival (PFS) and overall survival (OS) rates were 56.4% and 62.7%, respectively. Factors associated with decreased PFS and OS in univariate analysis were unfavorable PS and high international prognostic index. Elevated EBV DNA copy number was inclined to be associated with worse outcome. We did not observe a significant difference in survival between R-EPOCH and R-CHOP regimens. In our population, patients with HIV-associated DLBCL presented with aggressive characteristics and exhibited poor survival outcomes, even in the modern cART era.
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Receptor-interacting protein kinases 3 (RIPK3), a central node in necroptosis, polymerizes in response to the upstream signals and then activates its downstream mediator to induce cell death. The active polymeric form of RIPK3 has been indicated as the form of amyloid fibrils assembled via its RIP homotypic interaction motif (RHIM). In this study, we combine cryogenic electron microscopy and solid-state NMR to determine the amyloid fibril structure of RIPK3 RHIM-containing C-terminal domain (CTD). The structure reveals a single protofilament composed of the RHIM domain. RHIM forms three ß-strands (referred to as strands 1 through 3) folding into an S shape, a distinct fold from that in complex with RIPK1. The consensus tetrapeptide VQVG of RHIM forms strand 2, which zips up strands 1 and 3 via heterozipper-like interfaces. Notably, the RIPK3-CTD fibril, as a physiological fibril, exhibits distinctive assembly compared with pathological fibrils. It has an exceptionally small fibril core and twists in both handedness with the smallest pitch known so far. These traits may contribute to a favorable spatial arrangement of RIPK3 kinase domain for efficient phosphorylation.
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Amiloide/química , Proteína Serina-Treonina Quinases de Interação com Receptores/química , Motivos de Aminoácidos , Amiloide/metabolismo , Microscopia Crioeletrônica , Humanos , Necroptose , Fosforilação , Domínios Proteicos , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismoRESUMO
RIPK3 amyloid complex plays crucial roles during TNF-induced necroptosis and in response to immune defense in both human and mouse. Here, we have structurally characterized mouse RIPK3 homogeneous self-assembly using solid-state NMR, revealing a well-ordered N-shaped amyloid core structure featured with 3 parallel in-register ß-sheets. This structure differs from previously published human RIPK1/RIPK3 hetero-amyloid complex structure, which adopted a serpentine fold. Functional studies indicate both RIPK1-RIPK3 binding and RIPK3 amyloid formation are essential but not sufficient for TNF-induced necroptosis. The structural integrity of RIPK3 fibril with three ß-strands is necessary for signaling. Molecular dynamics simulations with a mouse RIPK1/RIPK3 model indicate that the hetero-amyloid is less stable when adopting the RIPK3 fibril conformation, suggesting a structural transformation of RIPK3 from RIPK1-RIPK3 binding to RIPK3 amyloid formation. This structural transformation would provide the missing link connecting RIPK1-RIPK3 binding to RIPK3 homo-oligomer formation in the signal transduction.
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Amiloide/metabolismo , Amiloide/ultraestrutura , Necroptose/fisiologia , Proteína Serina-Treonina Quinases de Interação com Receptores/química , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Benzotiazóis , Sobrevivência Celular , Drosophila , Herpesviridae , Humanos , Camundongos , Simulação de Dinâmica Molecular , Necroptose/genética , Conformação Proteica , Ratos , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Alinhamento de Sequência , Análise de Sequência de Proteína , Transdução de SinaisRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19) continue to impact countries worldwide. At present, inadequate diagnosis and unreliable evaluation systems hinder the implementation and development of effective prevention and treatment strategies. Here, we conducted a horizontal and longitudinal study comparing the detection rates of SARS-CoV-2 nucleic acid in different types of samples collected from COVID-19 patients and SARS-CoV-2-infected monkeys. We also detected anti-SARS-CoV-2 antibodies in the above clinical and animal model samples to identify a reliable approach for the accurate diagnosis of SARS-CoV-2 infection. Results showed that, regardless of clinical symptoms, the highest detection levels of viral nucleic acid were found in sputum and tracheal brush samples, resulting in a high and stable diagnosis rate. Anti-SARS-CoV-2 immunoglobulin M (IgM) and G (IgG) antibodies were not detected in 6.90% of COVID-19 patients. Furthermore, integration of nucleic acid detection results from the various sample types did not improve the diagnosis rate. Moreover, dynamic changes in SARS-CoV-2 viral load were more obvious in sputum and tracheal brushes than in nasal and throat swabs. Thus, SARS-CoV-2 nucleic acid detection in sputum and tracheal brushes was the least affected by infection route, disease progression, and individual differences. Therefore, SARS-CoV-2 nucleic acid detection using lower respiratory tract samples alone is reliable for COVID-19 diagnosis and study.