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1.
BMC Pulm Med ; 24(1): 172, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38600466

ABSTRACT

BACKGROUND: Bronchiectasis is a pulmonary disease characterized by irreversible dilation of the bronchi and recurring respiratory infections. Few studies have described the microbiology and prevalence of infections in large patient populations outside of specialized tertiary care centers. METHODS: We used the Cerner HealthFacts Electronic Health Record database to characterize the nature, burden, and frequency of pulmonary infections among persons with bronchiectasis. Chronic infections were defined based on organism-specific guidelines. RESULTS: We identified 7,749 patients who met our incident bronchiectasis case definition. In this study population, the organisms with the highest rates of isolate prevalence were Pseudomonas aeruginosa with 937 (12%) individuals, Staphylococcus aureus with 502 (6%), Mycobacterium avium complex (MAC) with 336 (4%), and Aspergillus sp. with 288 (4%). Among persons with at least one isolate of each respective pathogen, 219 (23%) met criteria for chronic P. aeruginosa colonization, 74 (15%) met criteria for S. aureus chronic colonization, 101 (30%) met criteria for MAC chronic infection, and 50 (17%) met criteria for Aspergillus sp. chronic infection. Of 5,795 persons with at least two years of observation, 1,860 (32%) had a bronchiectasis exacerbation and 3,462 (60%) were hospitalized within two years of bronchiectasis diagnoses. Among patients with chronic respiratory infections, the two-year occurrence of exacerbations was 53% and for hospitalizations was 82%. CONCLUSIONS: Patients with bronchiectasis experiencing chronic respiratory infections have high rates of hospitalization.


Subject(s)
Bronchiectasis , Pseudomonas Infections , Respiratory Tract Infections , Humans , United States/epidemiology , Anti-Bacterial Agents/therapeutic use , Persistent Infection , Staphylococcus aureus , Electronic Health Records , Bronchiectasis/epidemiology , Bronchiectasis/complications , Pseudomonas Infections/drug therapy , Respiratory Tract Infections/complications , Mycobacterium avium Complex , Pseudomonas aeruginosa
2.
Front Immunol ; 15: 1380049, 2024.
Article in English | MEDLINE | ID: mdl-38576607

ABSTRACT

Introduction: There is currently no vaccine against Chagas disease (ChD), and the medications available confer multiple side effects. Mycobacterium bovis Bacillus Calmette-Guérin (BCG) produces balanced Th1, Th2, and Th17 modulatory immune responses and has improved efficacy in controlling chronic infections through nonspecific immunity. We aimed to improve the response to infection by inducing a stronger immune response and greater protection against the parasite by trained immunity. Methods: BALB/c mice were immunized with BCG subcutaneously, and 60 days later, they were infected with Trypanosoma cruzi intraperitoneally. An evaluation of the progression of the disease from the acute to the chronic stage, analyzing various aspects such as parasitemia, survival, clinical status, and humoral and cellular immune response, as well as the appearance of visceral megas and the histopathological description of target organs, was performed. Results: Vaccination reduced parasitemia by 70%, and 100% survival was achieved in the acute stage; although the presentation of clinical signs was reduced, there was no increase in the antibody titer or in the differential production of the isotypes. Conclusion: Serum cytokine production indicated a proinflammatory response in infected animals, while in those who received BCG, the response was balanced by inducing Th1/Th2-type cytokines, with a better prognosis of the disease in the chronic stage.


Subject(s)
Chagas Disease , Mycobacterium bovis , Animals , Mice , BCG Vaccine , Parasitemia , Persistent Infection , Adjuvants, Immunologic
3.
Sci Rep ; 14(1): 8208, 2024 04 08.
Article in English | MEDLINE | ID: mdl-38589582

ABSTRACT

To investigate the effect of an exercise-based cardiac rehabilitation program on the quality of life (QoL) of patients with chronic Chagas cardiomyopathy (CCC). PEACH study was a single-center, superiority randomized clinical trial of exercise training versus no exercise (control). The sample comprised Chagas disease patients with CCC, left ventricular ejection fraction < 45%, without or with HF symptoms (CCC stages B2 or C, respectively). QoL was assessed at baseline, after three months, and at the end of six months of follow-up using the SF-36 questionnaire. Patients randomized for the exercise group (n = 15) performed exercise training (aerobic, strength and stretching exercises) for 60 min, three times a week, during six months. Patients in the control group (n = 15) were not provided with a formal exercise prescription. Both groups received identical nutritional and pharmaceutical counseling during the study. Longitudinal analysis of the effects of exercise training on QoL, considering the interaction term (group × time) to estimate the rate of changes between groups in the outcomes (represented as beta coefficient), was performed using linear mixed models. Models were fitted adjusting for each respective baseline QoL value. There were significant improvements in physical functioning (ß = + 10.7; p = 0.02), role limitations due to physical problems (ß = + 25.0; p = 0.01), and social functioning (ß = + 19.2; p < 0.01) scales during the first three months in the exercise compared to the control group. No significant differences were observed between groups after six months. Exercise-based cardiac rehabilitation provided short-term improvements in the physical and mental aspects of QoL of patients with CCC.Trial registration: ClinicalTrials.gov Identifier: NCT02517632; August 7, 2015.


Subject(s)
Cardiac Rehabilitation , Chagas Cardiomyopathy , Heart Failure , Humans , Cardiac Rehabilitation/methods , Quality of Life , Chagas Cardiomyopathy/therapy , Stroke Volume , Ventricular Function, Left , Exercise Therapy/methods , Exercise , Persistent Infection
4.
Autoimmunity ; 57(1): 2330394, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38497343

ABSTRACT

Soil-transmitted helminth (STH) among children aged 24-59 months is one cause of chronic infection that could lead to stunting. The association of 25(OH)D and immune responses during chronic infection in stunted populations has not yet been well established. An association study of case-control data was conducted in Bandung district from October 2019 to January 2023. Sociodemographic factors, stool samples, and serum levels of 25(OH)D, interleukin-4 (IL-4), interleukin-5 (IL-5), and interleukin-13 (IL-13) were assessed. Statistical analysis was performed to evaluate the prevalence and association of 25(OH)D, IL-4, IL-5, and IL-13 with the burden of STH infection in stunted children. In total, 401 stunted children were recruited. A higher burden of STH infection was found for lower levels of IL-5 (r = -0.477; p = 0.004) and IL-13 (r = -0.433; p = 0.028). Thus, 25(OH)D, IL-4, IL-5, and IL-13 play a role in the burden of STH infection.


Subject(s)
Helminthiasis , Helminths , Animals , Child , Humans , Helminthiasis/epidemiology , Helminthiasis/complications , Interleukin-13 , Interleukin-4 , Interleukin-5 , Persistent Infection , Soil
5.
Int J Mol Sci ; 25(6)2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38542493

ABSTRACT

Borna disease virus (BoDV-1) is a bornavirus that infects the central nervous systems of various animal species, including humans, and causes fatal encephalitis. BoDV-1 also establishes persistent infection in neuronal cells and causes neurobehavioral abnormalities. Once neuronal cells or normal neural networks are lost by BoDV-1 infection, it is difficult to regenerate damaged neural networks. Therefore, the development of efficient anti-BoDV-1 treatments is important to improve the outcomes of the infection. Recently, one of the clustered regularly interspaced short palindromic repeats (CRISPRs) and CRISPR-associated (Cas) systems, CRISPR/Cas13, has been utilized as antiviral tools. However, it is still unrevealed whether the CRISPR/Cas13 system can suppress RNA viruses in persistently infected cells. In this study, we addressed this question using persistently BoDV-1-infected cells. The CRISPR/Cas13 system targeting viral mRNAs efficiently decreased the levels of target viral mRNAs and genomic RNA (gRNA) in persistently infected cells. Furthermore, the CRISPR/Cas13 system targeting viral mRNAs also suppressed BoDV-1 infection if the system was introduced prior to the infection. Collectively, we demonstrated that the CRISPR/Cas13 system can suppress BoDV-1 in both acute and persistent infections. Our findings will open the avenue to treat prolonged infection with RNA viruses using the CRISPR/Cas13 system.


Subject(s)
Borna Disease , Borna disease virus , RNA Viruses , Animals , Humans , Borna disease virus/genetics , Persistent Infection , RNA, Guide, CRISPR-Cas Systems , RNA Viruses/genetics , Genome , CRISPR-Cas Systems/genetics , Borna Disease/genetics , Virus Replication/genetics
6.
Nat Commun ; 15(1): 2717, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38548737

ABSTRACT

Mycobacterium abscessus is an opportunistic, extensively drug-resistant non-tuberculous mycobacterium. Few genomic studies consider its diversity in persistent infections. Our aim was to characterize microevolution/reinfection events in persistent infections. Fifty-three sequential isolates from 14 patients were sequenced to determine SNV-based distances, assign resistance mutations and characterize plasmids. Genomic analysis revealed 12 persistent cases (0-13 differential SNVs), one reinfection (15,956 SNVs) and one very complex case (23 sequential isolates over 192 months), in which a first period of persistence (58 months) involving the same genotype 1 was followed by identification of a genotype 2 (76 SNVs) in 6 additional alternating isolates; additionally, ten transient genotypes (88-243 SNVs) were found. A macrolide resistance mutation was identified from the second isolate. Despite high diversity, the genotypes shared a common phylogenetic ancestor and some coexisted in the same specimens. Genomic analysis is required to access the true intra-patient complexity behind persistent infections involving M. abscessus.


Subject(s)
Mycobacterium Infections, Nontuberculous , Mycobacterium abscessus , Humans , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Mycobacterium Infections, Nontuberculous/microbiology , Macrolides , Phylogeny , Persistent Infection , Reinfection , Drug Resistance, Bacterial/genetics , Genomics , Microbial Sensitivity Tests
7.
BMC Prim Care ; 25(1): 86, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38486181

ABSTRACT

BACKGROUND: Early detection of long-term, often asymptomatic, middle ear infection in young Aboriginal and Torres Strait Islander children is more likely to be achieved when ear health and hearing checks are routinely undertaken in primary healthcare. Evidence consistently demonstrates the adverse impacts of this condition on the development and wellbeing of children and their families. We aimed to develop feasible, evidence- and consensus-based primary healthcare recommendations addressing the components and timing of ear health and hearing checks for Aboriginal and Torres Strait Islander children aged under 6 years, not already known to have, nor being actively managed for, ear and hearing problems. METHODS: A 22-person working group comprising Aboriginal and Torres Strait Islander and non-Indigenous members from the primary healthcare, ear, hearing, and research sectors provided guidance of the project. A systematic scoping review addressed research questions relating to primary health ear health and hearing checks for Aboriginal and Torres Strait Islander and other populations at increased risk of persistent ear health problems. Twelve primary studies and eleven guidelines published between 1998 and 2020 were identified and reviewed. Quality and certainty of evidence and risk of bias ratings were completed for studies and guidelines. In the absence of certain and direct evidence, findings and draft recommendations were presented for consensus input to a 79-member expert panel using a modified e-Delphi process. Recommendations were finalised in consultation with working group members and presented to expert panel members for input on considerations relating to implementation. RESULTS: Overall, the quality, certainty, and directness of evidence in the studies and guidelines reviewed was low. However, the findings provided a basis and structure for the draft recommendations presented during the consensus-building process. After two e-Delphi rounds, seven goals and eight recommendations on the components and timing of Ear Health and Hearing Checks in primary healthcare for young Aboriginal and Torres Strait Islander children were developed. CONCLUSIONS: The systematic scoping review and consensus-building process provided a pragmatic approach for producing strong recommendations within a reasonably short timeframe, despite the low quality and certainty of evidence, and paucity of studies pertaining to primary healthcare settings.


Subject(s)
Australian Aboriginal and Torres Strait Islander Peoples , Deafness , Child , Humans , Hearing , Consensus , Persistent Infection , Primary Health Care
8.
PLoS One ; 19(3): e0299904, 2024.
Article in English | MEDLINE | ID: mdl-38489252

ABSTRACT

BACKGROUND: Integrated health care is an approach characterized by a high degree of collaboration and communication among health professionals. Integration of HIV/NCD is recommended to enhance the quality of healthcare services being provided. Duplication of limited resources is minimized, and a holistic care approach is promoted by shifting from acute and reactive care to care that embraces patient-centredness that includes promotive health and disease surveillance. The high burden of HIV disease in sub-Saharan Africa (SSA) combined with the increasing prevalence of chronic non-communicable diseases (NCDs) necessitates a review of how health systems has been doing to deliver quality integrated care for people living with HIV (PLWH) and comorbid chronic NCDs. METHODS: A scoping review was conducted to identify and describe all publications on integrated chronic care management models at the primary care level in the SSA context, particularly those that addressed the care of PLHIV with co-morbid chronic NCDs. The inclusion and exclusion criteria were applied, and duplicates were removed. RESULTS: A total of twenty-one articles were included in the final review. Integrated healthcare systems were reported in only eight SSA countries-(South Africa, Uganda, Kenya, the United Republic of Tanzania, Zambia, Malawi, Zimbabwe and Swaziland). Integrated care systems adopted one of three health models. These included added-on NCD services to previously dedicated HIV care facilities, expansion of primary care facilities to include HIV care and establishment of integrated care services. Short-term benefits included staff capacitation, improved retention of patients and improved screening and detection of NCDs. However, the expansion of existing services resulted in an increased workload with no additional staff. A significant positive change noted by communities was that there was less or no stigmatisation of people living with HIV when attending dedicated HIV clinics. CONCLUSION: Evidence of integrated healthcare services for PLWH and co-morbid of NCDs in SSA is scanty. Data on some short-term benefits of integrated care was available, but evidence was absent on the long-term outcomes. Randomized clinical trials with clearly defined comparator groups and standardized measures of HIV and NCD outcomes are needed to demonstrate non-inferiority of integrated against non-integrated care.


Subject(s)
Delivery of Health Care, Integrated , HIV Infections , Noncommunicable Diseases , Humans , Noncommunicable Diseases/therapy , Noncommunicable Diseases/prevention & control , HIV Infections/complications , HIV Infections/epidemiology , HIV Infections/therapy , Comorbidity , Persistent Infection , South Africa
9.
Proc Natl Acad Sci U S A ; 121(11): e2318599121, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38446856

ABSTRACT

T cells help orchestrate immune responses to pathogens, and their aberrant regulation can trigger autoimmunity. Recent studies highlight that a threshold number of T cells (a quorum) must be activated in a tissue to mount a functional immune response. These collective effects allow the T cell repertoire to respond to pathogens while suppressing autoimmunity due to circulating autoreactive T cells. Our computational studies show that increasing numbers of pathogenic peptides targeted by T cells during persistent or severe viral infections increase the probability of activating T cells that are weakly reactive to self-antigens (molecular mimicry). These T cells are easily re-activated by the self-antigens and contribute to exceeding the quorum threshold required to mount autoimmune responses. Rare peptides that activate many T cells are sampled more readily during severe/persistent infections than in acute infections, which amplifies these effects. Experiments in mice to test predictions from these mechanistic insights are suggested.


Subject(s)
Autoimmune Diseases , Persistent Infection , Animals , Mice , Peripheral Tolerance , T-Lymphocytes , Autoantigens , Peptides
10.
BMC Genom Data ; 25(1): 27, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38443836

ABSTRACT

OBJECTIVES: The black rhinoceros (Diceros bicornis) is an endangered mammal for which a captive breeding program is part of the conservation effort. Black rhinos in zoo's often suffer from chronic infections and heamochromatosis. Furthermore, breeding is hampered by low male fertility. To aid a research project studying these topics, we sequenced and assembled the genome of a captive male black rhino using ONT sequencing data only. DATA DESCRIPTION: This work produced over 100 Gb whole genome sequencing reads from whole blood. These were assembled into a 2.47 Gb draft genome consisting of 834 contigs with an N50 of 29.53 Mb. The genome annotation was lifted over from an available genome annotation for black rhino, which resulted in the retrieval of over 99% of gene features. This new genome assembly will be a valuable resource in for conservation genetic research in this species.


Subject(s)
Genetic Research , Nose , Male , Animals , Perissodactyla/genetics , Persistent Infection , Research Design
11.
Sci Rep ; 14(1): 7536, 2024 03 29.
Article in English | MEDLINE | ID: mdl-38553516

ABSTRACT

The stool antigen test (SAT) and the serum Helicobacter pylori (H. pylori) IgG antibody assays exhibit significant utility in the clinical diagnosis of H. pylori infection and in distinguishing between acute and chronic infections. The main objective of the current study was to identify the diagnostic value of serum H. pylori IgG antibody and SAT in the detection of H. pylori infections among chronic H. pylori-infected patients residing in Ibb Governorate, Yemen. 200 patients with H. pylori infection, confirmed through positive results in the serum immunochromatographic antibody test, were selected for H. pylori infection confirmation using serum H. pylori IgG antibodies and SAT across diverse hospitals, gastroenterology, and Hepatology clinics in Ibb Governorate. After the selection of patients, blood and stool specimens were obtained from all participants and underwent analysis via the Statistical Package for the Social Sciences (SPSS). The prevalence of H. pylori infection demonstrated variability based on the confirmatory tests, with rates of 54% for SAT and 78.5% for serum H. pylori IgG antibody, contrasting with a 100% prevalence observed in the screening serum immunochromatographic antibody test. Clinically, the study categorized H. pylori infections into four stages, whereby a significant proportion of patients (40.5%) exhibited positivity for both serum H. pylori IgG antibody and SAT, indicative of active chronic infections. The majority of positive cases only manifested serum H. pylori IgG antibody presence (chronic infections) at 38%, whereas 13.5% exclusively tested positive for SAT, corresponding to acute infections. Moreover, 88% of patients did not have either serum H. pylori IgG antibody or SAT (absence of infections) during confirmatory tests. Noteworthy is the study's approach employing multiple tests for H. pylori infection detection, focusing predominantly on chronic infections-prevailing types caused by H. pylori. The results revealed a significant association between serum levels of H. pylori IgG antibody and SAT results with the presence of diverse gastrointestinal symptoms among patients, which increased with long H. pylori infection durations.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Humans , Helicobacter Infections/diagnosis , Helicobacter Infections/epidemiology , Immunoglobulin G , Yemen/epidemiology , Persistent Infection , Serologic Tests , Antibodies, Bacterial , Antigens, Bacterial/analysis , Sensitivity and Specificity
12.
Front Immunol ; 15: 1341600, 2024.
Article in English | MEDLINE | ID: mdl-38482000

ABSTRACT

The COVID-19 pandemic continues to cause severe global disruption, resulting in significant excess mortality, overwhelming healthcare systems, and imposing substantial social and economic burdens on nations. While most of the attention and therapeutic efforts have concentrated on the acute phase of the disease, a notable proportion of survivors experience persistent symptoms post-infection clearance. This diverse set of symptoms, loosely categorized as long COVID, presents a potential additional public health crisis. It is estimated that 1 in 5 COVID-19 survivors exhibit clinical manifestations consistent with long COVID. Despite this prevalence, the mechanisms and pathophysiology of long COVID remain poorly understood. Alarmingly, evidence suggests that a significant proportion of cases within this clinical condition develop debilitating or disabling symptoms. Hence, urgent priority should be given to further studies on this condition to equip global public health systems for its management. This review provides an overview of available information on this emerging clinical condition, focusing on the affected individuals' epidemiology, pathophysiological mechanisms, and immunological and inflammatory profiles.


Subject(s)
COVID-19 , Post-Acute COVID-19 Syndrome , Humans , Pandemics , Kinetics , Persistent Infection
13.
Int Immunopharmacol ; 131: 111821, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38484664

ABSTRACT

Chlamydia trachomatis (C.tr), an obligate intracellular pathogen, causes asymptomatic genital infections in women and is a leading cause of preventable blindness. We have developed in vivo mouse models of acute and chronic C. trachomatis genital infection to explore the significance of macrophage-directed response in mediating immune activation/suppression. Our findings reveal that during chronic and repeated C. trachomatis infections, Th1 response is abated while Treg response is enhanced. Additionally, an increase in exhaustion (PD1, CTLA4) and anergic (Klrg3, Tim3) T cell markers is observed during chronic infection. We have also observed that M2 macrophages with low CD40 expression promote Th2 and Treg differentiation leading to sustained C. trachomatis genital infection. Macrophages infected with C. trachomatis or treated with supernatant of infected epithelial cells drive them to an M2 phenotype. C. trachomatis infection prevents the increase in CD40 expression as observed in western blots and flow cytometric analysis. Insufficient IFNγ, as observed during chronic infection, leads to incomplete clearance of bacteria and poor immune activation. C. trachomatis decapacitates IFNγ responsiveness in macrophages via hampering IFNγRI and IFNγRII expression which can be correlated with poor expression of MHC-II, CD40, iNOS and NO release even following IFNγ supplementation. M2 macrophages during C. trachomatis infection express low CD40 rendering immunosuppressive, Th2 and Treg differentiation which could not be reverted even by IFNγ supplementation. The alternative macrophages also harbour high bacterial load and are poor responders to IFNγ, thus promoting immunosuppression. In summary, C. trachomatis modulates the innate immune cells, attenuating the anti-chlamydial functions of T cells in a manner that involves decreased CD40 expression on macrophages.


Subject(s)
CD40 Antigens , Chlamydia Infections , Chlamydia trachomatis , Interferon-gamma , Macrophages , Animals , Female , Humans , Mice , CD40 Antigens/metabolism , Chlamydia Infections/immunology , Chlamydia Infections/microbiology , Chlamydia trachomatis/physiology , Epithelial Cells , Lymphocyte Activation , Macrophages/metabolism , Persistent Infection , Interferon-gamma/immunology , Interferon-gamma/metabolism
14.
Front Immunol ; 15: 1334762, 2024.
Article in English | MEDLINE | ID: mdl-38533492

ABSTRACT

Salmonella enterica serovar Typhi (S. Typhi), a human-restricted pathogen, invades the host through the gut to cause typhoid fever. Recent calculations of the typhoid fever burden estimated that more than 10 million new typhoid fever cases occur in low and middle-income countries, resulting in 65,400-187,700 deaths yearly. Interestingly, if not antibiotic-treated, upon the resolution of acute disease, 1%-5% of patients become asymptomatic chronic carriers. Chronically infected hosts are not only critical reservoirs of infection that transmit the disease to naive individuals but are also predisposed to developing gallbladder carcinoma. Nevertheless, the molecular mechanisms involved in the early interactions between gallbladder epithelial cells and S. Typhi remain largely unknown. Based on our previous studies showing that closely related S. Typhi strains elicit distinct innate immune responses, we hypothesized that host molecular pathways activated by S. Typhi strains derived from acutely and chronically infected patients would differ. To test this hypothesis, we used a novel human organoid-derived polarized gallbladder monolayer model, and S. Typhi strains derived from acutely and chronically infected patients. We found that S. Typhi strains derived from acutely and chronically infected patients differentially regulate host mitogen-activated protein kinase (MAPK) and S6 transcription factors. These variations might be attributed to differential cytokine signaling, predominantly via TNF-α and IL-6 production and appear to be influenced by the duration the isolate was subjected to selective pressures in the gallbladder. These findings represent a significant leap in understanding the complexities behind chronic S. Typhi infections in the gallbladder and may uncover potential intervention targets.


Subject(s)
Salmonella typhi , Typhoid Fever , Humans , Gallbladder/pathology , Persistent Infection , Immunity
15.
Microbiol Immunol ; 68(5): 179-184, 2024 May.
Article in English | MEDLINE | ID: mdl-38433377

ABSTRACT

BK polyomavirus (BKPyV) was the first human polyomavirus to be isolated from an immunosuppressed kidney transplant recipient in 1971. BKPyV reactivation causes BKPyV-associated nephropathy and hemorrhagic cystitis. However, the mechanisms underlying BKPyV replication remain unclear. In the present study, we performed the long-term cultivation of COS-7 cells transfected with archetype KOM-5 DNA, which were designated as COS-BK cells. BKPyV derived from COS-BK cells was characterized by analyzing the amount of the virus based on hemagglutination, viral replication, and the production of viral protein 1 (VP1). Immunostaining showed that VP1-positive cells accounted for a small percentage of COS-BK cells. The nucleotide sequences encompassing the origin of the DNA replication of BKPyV derived from COS-BK cells were generated from KOM-5 by the deletion of an 8-bp sequence, which did not involve T antigen binding sites. BKPyV replicated most efficiently in COS-BK cells in DMEM containing 2% fetal bovine serum. These results indicate that COS-BK cells are a suitable culture system for studying the persistent infection of archetype BKPyV.


Subject(s)
BK Virus , Polyomavirus Infections , Virus Replication , BK Virus/physiology , BK Virus/genetics , Animals , Chlorocebus aethiops , COS Cells , Polyomavirus Infections/virology , Humans , Capsid Proteins/genetics , DNA, Viral/genetics , Persistent Infection/virology , Antigens, Viral, Tumor/genetics , Tumor Virus Infections/virology
16.
J Virol ; 98(3): e0169823, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38358288

ABSTRACT

Crimean-Congo hemorrhagic fever virus (CCHFV), a tick-borne virus of the Orthonairovirus genus, persistently infects tick cells. It has been reported to establish persistent infection in non-human primates, but virological analysis has not yet been performed in human cells. Here, we investigated whether and how nairoviruses persistently infect human cells using Hazara orthonairovirus (HAZV), a surrogate model for CCHFV. We established a human cell line that was persistently infected with HAZV. Surprisingly, virions of persistently infected HAZV (HAZVpi) were not observed in the culture supernatants. There were five mutations (mut1, mut2, mut3, mut4, and mut5) in L protein of HAZVpi. Mutations in L protein of HAZVpi contribute to non-detection of virion in the supernatants. Lmut4 was found to cause low viral growth rate, despite its high polymerase activity. The low growth rate was restored by Lmut2, Lmut3, and Lmut5. The polymerase activity of Lmut1 was extremely low, and recombinant HAZV carrying Lmut1 (rHAZV/Lmut1) was not released into the supernatants. However, genomes of rHAZV/Lmut1 were retained in the infected cells. All mutations (Lmut1-5) found in L protein of HAZVpi were required for experimental reproduction of HAZVpi, and only Lmut1 and Lmut4 were insufficient. We demonstrated that point mutations in viral polymerase contribute to the establishment of persistent HAZV infection. Furthermore, innate immunity was found to be suppressed in HAZVpi-infected cells, which also potentially contributes to viral persistence. This is the first presentation of a possible mechanism behind how nairoviruses establish persistent infection in human cells. IMPORTANCE: We investigated whether and how nairoviruses persistently infect human cells, using Hazara orthonairovirus (HAZV), a surrogate model for Crimean-Congo hemorrhagic fever virus. We established a human cell line that was persistently infected with HAZV. Five mutations were found in L protein of persistently infected HAZV (HAZVpi): mut1, mut2, mut3, mut4, and mut5. Among them, Lmut1 and Lmut4 restricted viral growth by low polymerase activity and low growth rate, respectively, leading to inhibition of viral overgrowth. The restriction of viral growth caused by Lmut1 and Lmut4 was compensated by other mutations, including Lmut2, Lmut3, and Lmut5. Each of the mutations found in L protein of HAZVpi was concluded to cooperatively modulate viral growth, which facilitates the establishment of persistent infection. Suppression of innate immunity also potentially contributes to virus persistence. This is the first presentation of a possible mechanism behind how nairoviruses establish persistent infection in human cells.


Subject(s)
Bunyaviridae Infections , Nairovirus , Animals , Humans , Cell Line , Hemorrhagic Fever Virus, Crimean-Congo/physiology , Hemorrhagic Fever, Crimean/virology , Mutation , Nairovirus/genetics , Persistent Infection , Bunyaviridae Infections/virology
17.
Nat Commun ; 15(1): 1615, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38388565

ABSTRACT

The ability of Mycobacterium tuberculosis (Mtb) to persist in the host complicates and prolongs tuberculosis (TB) patient chemotherapy. Here we demonstrate that a neglected two-component system (TCS) of Mtb, TcrXY, is an autoregulated acid-sensing TCS that controls a functionally diverse 70-gene regulon required for bacterial persistence. Characterisation of two representatives of this regulon, Rv3706c and Rv3705A, implicate these genes as key determinants for the survival of Mtb in vivo by serving as important effectors to mitigate redox stress at acidic pH. We show that genetic silencing of the response regulator tcrX using CRISPR interference attenuates the persistence of Mtb during chronic mouse infection and improves treatment with the two front-line anti-TB drugs, rifampicin and isoniazid. We propose that targeting TcrXY signal transduction blocks the ability of Mtb to sense and respond to acid stress, resulting in a disordered program of persistence to render the organism vulnerable to existing TB chemotherapy.


Subject(s)
Genes, Bacterial , Mycobacterium tuberculosis , Animals , Humans , Mice , Antitubercular Agents/chemistry , Genes, Bacterial/physiology , Isoniazid , Mycobacterium tuberculosis/genetics , Persistent Infection , Rifampin
18.
Arch Microbiol ; 206(3): 95, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38349529

ABSTRACT

Candida albicans is a commensal fungus that infects the humans and becomes an opportunistic pathogen particularly in immuno-compromised patients. Among the Candida genus, yeast C. albicans is the most frequently incriminated species and is responsible for nearly 50-90% of human candidiasis, with vulvovaginal candidiasis alone, affecting about 75% of the women worldwide. One of the significant virulence traits in C. albicans is its tendency to alternate between the yeast and hyphae morphotypes, accounting for the development of multi-drug resistance in them. Thus, a thorough comprehension of the decision points and genes controlling this transition is necessary, to understand the pathogenicity of this, naturally occurring, pernicious fungus. Additionally, the formation of C. albicans biofilm is yet another pathogenesis trait and a paramount cause of invasive candidiasis. Since 1980 and in 90 s, wide spread use of immune-suppressing therapies and over prescription of fluconazole, a drug used to treat chronic fungal infections, triggered the emergence of novel anti-fungal drug development. Thus, this review thoroughly elucidates the diseases associated with C. albicans infection as well as the anti-fungal resistance mechanism associated with them and identifies the emerging therapeutic agents, along with a rigorous discussion regarding the future strategies that can possibly be adopted for the cure of this deleterious pathogen.


Subject(s)
Candida albicans , Candidiasis , Humans , Female , Candida albicans/genetics , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Candidiasis/drug therapy , Candida , Drug Resistance, Fungal , Persistent Infection
19.
PLoS One ; 19(2): e0297622, 2024.
Article in English | MEDLINE | ID: mdl-38394315

ABSTRACT

INTRODUCTION: Non-communicable diseases (NCDs) currently cause more deaths than all other causes of deaths. Cardiovascular disease, diabetes, cancer, and chronic respiratory diseases-threaten the health and economies of individuals and populations worldwide. This study aimed to assess the availability and readiness of health facilities for chronic non-communicable diseases (NCDs) and describe the changes of service availability for common NCDs in Ethiopia. Methods We used data from the 2014 Ethiopia Service Provision Assessment Plus (ESPA +) and 2016 and 2018 Service Availability and Readiness Assessment (SARA) surveys, which were cross-sectional health facility-based studies. A total of 873 health facilities in 2014, 547 in 2016, 632 in 2018 were included in the analysis. (ESPA+) and SARA surveys are conducted as a census or a nationally/sub-nationally representative sample of health facilities. Proportion of facilities that offered the service for diabetes, cardiovascular disease, chronic respiratory disease, cancer diseases, mental illness, and chronic renal diseases was calculated to measure health service availability. The health facility service readiness was measured using the mean availably of tracer items that are required to offer the service. Thus, 13 tracer items for diabetes disease, 12 for cardiovascular disease, 11 for chronic respiratory disease and 11 cervical cancer services were used. RESULTS: The services available for diagnosis and management did not show improvement between 2014, 2016 and 2018 for diabetes (59%, 22% and 36%); for cardiovascular diseases (73%, 41% and 49%); chronic respiratory diseases (76%, 45% and 53%). Similarly, at the national level, the mean availability of tracer items between 2014, 2016 and 2018 for diabetes (37%, 53% and 48%); cardiovascular diseases (36%, 41% and 42%); chronic respiratory diseases (26%, 27% and 27%); and cancer diseases (6%, 72% and 51%). However, in 2014 survey year, the mean availability of tracer items was 7% each for mental illness and chronic renal diseases, respectively. CONCLUSIONS: The majority of the health facilities have low and gradual decrement in the availability to provide NCDs services in Ethiopia. There is a need to increase NCD service availability and readiness at primary hospitals and health centers, and private and rural health facilities where majority of the population need the services.


Subject(s)
Cardiovascular Diseases , Diabetes Mellitus , Neoplasms , Noncommunicable Diseases , Renal Insufficiency, Chronic , Respiration Disorders , Humans , Cardiovascular Diseases/epidemiology , Noncommunicable Diseases/epidemiology , Health Services Accessibility , Health Facilities , Persistent Infection , Neoplasms/diagnosis , Neoplasms/epidemiology , Diabetes Mellitus/epidemiology , Diabetes Mellitus/therapy , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/epidemiology , Renal Insufficiency, Chronic/therapy
20.
Sci Immunol ; 9(93): eadj4748, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38330097

ABSTRACT

CD11c+ atypical B cells (ABCs) are an alternative memory B cell lineage associated with immunization, infection, and autoimmunity. However, the factors that drive the transcriptional program of ABCs have not been identified, and the function of this population remains incompletely understood. Here, we identified candidate transcription factors associated with the ABC population based on a human tonsillar B cell single-cell dataset. We identified CD11c+ B cells in mice with a similar transcriptomic signature to human ABCs, and using an optimized CRISPR-Cas9 knockdown screen, we observed that loss of zinc finger E-box binding homeobox 2 (Zeb2) impaired ABC formation. Furthermore, ZEB2 haplo-insufficient Mowat-Wilson syndrome (MWS) patients have decreased circulating ABCs in the blood. In Cd23Cre/+Zeb2fl/fl mice with impaired ABC formation, ABCs were dispensable for efficient humoral responses after Plasmodium sporozoite immunization but were required to control recrudescent blood-stage malaria. Immune phenotyping revealed that ABCs drive optimal T follicular helper (TFH) cell formation and germinal center (GC) responses and they reside at the red/white pulp border, likely permitting better access to pathogen antigens for presentation. Collectively, our study shows that ABC formation is dependent on Zeb2, and these cells can limit recrudescent infection by sustaining GC reactions.


Subject(s)
Germinal Center , Persistent Infection , Animals , Humans , Mice , Immunization , Vaccination , Zinc Finger E-box Binding Homeobox 2/genetics
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