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Background Antimicrobial resistance is a global challenging issue in children and adults. Finding the extent of resistance is the first step in finding an appropriate way to combat it. This study aimed to assess the antibiotic resistance patterns of different bacterial isolates in urine specimens from children and adults. Methods This retrospective cross-sectional study was done from January 1, 2014, to December 30, 2018, and used data from bacterial cultures collected and processed at the Centre Universitaire de Diagnostic au Graben (CUDG), located in Butembo in the Eastern part of the Democratic Republic of Congo. Conventional standard urine culture followed by bacteria identification based on conventional methods (colony morphology, Gram stain, and biochemical tests) were performed. Standard disc diffusion drug susceptibility testing was performed using CLSI M 100-S22 guidelines. Findings Of 1620 urine specimens collected, 1041 (64.3%) showed positive microorganism growth. The three most isolated bacterial microorganisms were S. aureus (561 [53.9%]), E. coli (124 [11.9%]), and Streptococcus spp (74 [7.1%]). Resistance of S. aureus was as follows: amoxicillin/clavulanic acid 50.3% (234 of 465 isolated tested), gentamicin 37.9% (167/441), ceftriaxone (329/469), ciprofloxacin (207/509), doxycycline (232/524), nalidixic acid (73/92) and meropenem (64/88). The resistance profile of E. coli was as follows: amoxicillin/clavulanic acid 77.8% (70/90), gentamicin % (44/95), ceftriaxone (45/108), ciprofloxacin (55/113), doxycycline (78/108), nalidixic acid (56/73) and meropenem (33/55). Resistance of Streptococci spp was amoxicillin/clavulanic acid 34.9% (23/66), gentamicin % (26/56), ceftriaxone (28/62), ciprofloxacin (28/66), doxycycline (28/64), nalidixic acid (14/17) and meropenem (7/8). Among the isolated bacteria, 66.8% (695/1041) were multidrug-resistant. Conclusion Antimicrobial resistance is prevalent among isolated uropathogenic bacteria, especially to first-line and second-line antibiotics. Continued surveillance and a tracking system for multidrug-resistant bacteria are needed. Judicious and rational antibiotic usage is recommended.

Radical new possibilities of improved treatment of cancer are on offer from an advanced medical technology already demonstrating its significance: next-generation sequencing (NGS). This refined testing provides unprecedentedly precise diagnoses and permits the use of focused and highly personalized treatments. However, across regions globally, many cancer patients will continue to be denied the benefits of NGS as long as some of the yawning gaps in its implementation remain unattended. The challenges at the regional and national levels are linked because putting the solutions into effect is highly dependent on cooperation between regional- and national-level cooperation, which could be hindered by shortfalls in interpretation or understanding. The aim of the paper was to define and explore the necessary conditions for NGS and make recommendations for effective implementation based on extensive exchanges with policy makers and stakeholders. As a result, the European Alliance for Personalised Medicine (EAPM) developed a maturity framework structured around demand-side and supply-side issues to enable interested stakeholders in different countries to self-evaluate according to a common matrix. A questionnaire was designed to identify the current status of NGS implementation, and it was submitted to different experts in different institutions globally. This revealed significant variability in the different aspects of NGS uptake. Within different regions globally, to ensure those conditions are right, this can be improved by linking efforts made at the national level, where patients have needs and where care is delivered, and at the global level, where major policy initiatives in the health field are underway or in preparation, many of which offer direct or indirect pathways for building those conditions. In addition, in a period when consensus is still incomplete and catching up is needed at a political level to ensure rational allocation of resources—even within individual countries—to enable the best ways to make the necessary provisions for NGS, a key recommendation is to examine where closer links between national and regional actions could complement, support, and mutually reinforce efforts to improve the situation for patients.

Background In December 2015, an outbreak of yellow fever virus (YFV) infection was reported in Angola, characterized by fever and jaundice, with at least one of the following symptoms: headache, asthenia, conjunctivitis, vomiting, with a different type of haemorrhage. Methods A total of 4,618 cases of yellow fever (YF) were referred to the national referral laboratory of the Instituto Nacional de Investigação em Saúde, from December 5, 2015 through December 23, 2016 that were analyzed using ELISA, and subsequently samples were confirmed using consensus primers for RT-PCR assay. Results We detected 884 (4%) cases that were positive on ELISA and RT-PCR assays. Patients were reported from 16 provinces of Angola. The incidence was approximately three times as high among male patients (10.88% per 100,000) than among female patients (2.65% per 100,000) in the 20 to 29 age group. Conclusions This study represents the transmission of YFV human-to-human via the bite of the infected vector. The re-emergence of YFV is a huge concern for a national public health system. Thus, laboratory and public health surveillance systems have to be strengthened to alleviate the risk of re-emerging human infections.

Objectives The introduction of Personalised Medicine (PM) into healthcare systems could benefit from a clearer understanding of the distinct national and regional frameworks around the world. Recent engagement by international regulators on maximising the use of real-world evidence (RWE) has highlighted the scope for improving the exploitation of the treasure-trove of health data that is currently largely neglected in many countries. The European Alliance for Personalised Medicine (EAPM) led an international study aimed at identifying the current status of conditions. Methods A literature review examined how far such frameworks exist, with a view to identifying conducive factors – and crucial gaps. This extensive review of key factors across 22 countries and 5 regions revealed a wide variety of attitudes, approaches, provisions and conditions, and permitted the construction of a comprehensive overview of the current status of PM. Based on seven key pillars identified from the literature review and expert panels, the data was quantified, and on the basis of further analysis, an index was developed to allow comparison country by country and region by region. Results The results show that United States of America is leading according to overall outcome whereas Kenya scored the least in the overall outcome. Conclusions Still, common approaches exist that could help accelerate take-up of opportunities even in the less prosperous parts of the world.

Background SARS-CoV-2 infection is a global public health concern. Several aspects related to the pattern of infection remain unclear. Herein, we investigated the blood pressure pattern among blood donors exposed to SARS-CoV-2 in Luanda, the capital city of Angola, a sub-Saharan African country. Methods We performed a retrospective analysis containing 343 blood donors from December 2019 to September 2020. Parametric tests compared means while Chi-square and logistic regression checked features associated with high blood pressure and were considered significant when p 0.05). A statistically significant link was observed, between the Rhesus factor and blood pressure status (p = 0.032). Conclusions We showed important variations in blood pressure indices of the Angolan population exposed to SARS-CoV-2. Older age and non-O blood groups appear to be important biological factors for SARS-CoV-2 infection, as well as the risk of developing cardiovascular disease after or during SARS-CoV-2 exposure. Further studies assessing the impact on cardiovascular functions with ongoing or long-term SARS-CoV-2 exposure in individuals from resource-limited countries should be considered.

Sandip Patil,1– 3 Hongyu Chen,4 Chunna Guo,4 Xiaoli Zhang,3 Pei-Gen Ren,1 Ngiambudulu M Francisco,5 Feiqiu Wen2,3 1Shenzhen Institute of Advanced Technology, Shenzhen University Town, Shenzhen, Guangdong Province, People’s Republic of China; 2Department of Haematology and Oncology, Shenzhen Children’s Hospital, Shenzhen, Guangdong Province, People’s Republic of China; 3Paediatric Research Institute, Shenzhen Children’s Hospital, Shenzhen, Guangdong Province, People’s Republic of China; 4Department of Laboratory Medicine, Shenzhen Children’s Hospital, Shenzhen, Guangdong Province, People’s Republic of China; 5Grupo de Investigação Microbiana e Imunológica, Instituto Nacional de Investigação em Saúde (National Institute for Health Research), Luanda, AngolaCorrespondence: Feiqiu WenDepartment of Haematology and Oncology, Shenzhen Children’s Hospital, Shenzhen, Guangdong Province, People’s Republic of ChinaTel +86 18938690333Fax +86-755 83009888Email fwen62@163.comAim: We investigated the clonal diversity of carbapenemase-producing Klebsiella pneumoniae isolates from the Shenzhen Children’s Hospital, China, and drew conclusions on the clinical and public health impact of these isolates as multidrug-resistant.Methods: From January 2014 to December 2018, a total number of 36 unique carbapenemase-producing clinical isolates of Klebsiella pneumoniae were collected out of 900 clinical isolates in paediatric patients from the Shenzhen Children’s Hospital, China. After carbapenemase production confirmation, antimicrobial susceptibility, resistance determinants and phylogenetic relationship were determined.Results: The isolates showed resistance to ceftazidime, ertapenem, ampicillin, cefazolin, ceftriaxone, cefotetan, ticarcillin, cefaclor, cefpodoxime, azlocillin, cefcapene, mezlocillin and ampicillin-sulbactam. Of the 36 Klebsiella pneumoniae carbapenemase genes coding isolates, blaNDM was the mostly detected 50% (n=18) followed by blaKPC and blaIMP 19% (n=7), blaVIM 17% (n=6), blaOXA-48-like 8% (n=3) and blaSME 5% (n=2), whereas extended-spectrum β-lactamase (blaSHV) was predominantly detected 92% (n=33) followed by blaCTX-M 53% (n=19) and blaCMY 28% (n=10). Pulsed-field gel electrophoresis typing showed eight different patterns, and twenty-five distinct sequences types were observed with ST307 being predominantly identified 11% (n=4), followed by ST2407 8% (n=3). Plasmid replicon typing results indicated that IncFIS, IncHI2, IncFIC and IncFIA plasmids carry blaCTX-M, blaSHV and blaNDM genes.Conclusion: This study reports on the occurrence and spread of carbapenemase and extended-spectrum β-lactamase encoding genes co-existence in sporadic Klebsiella pneumoniae ST307 in paediatric patients from the Shenzhen Children’s Hospital, China.Keywords: Klebsiella pneumoniae, carbapenemase, ESBLs, antimicrobial susceptibility, molecular characterization

Objective(s): This study aimed to explore the contribution of tumor necrosis factor (TNF) in the recruitment of B-cell and secretion of immunoglobulins (Igs) during cerebral tuberculosis (TB).Materials and Methods: In this work, the contributing role of TNF in regulating Ig secretions was investigated by comparing wild type TNF (TNFf/f), B-cell-derived TNF (BTNF-/-), and complete TNF ablation (TNF-/-) in a mouse cerebral Mycobacterium tuberculosis infection. Using flow cytometry and ELISA, we were able to examine the recruitment of B-cell subsets, and the production of Igs; also assessed the expression of surface markers on B cell subsets. Results: Here, we found that TNF-/- mice showed defective expression of IgA, IgG, and IgM antibodies compared with TNFf/f and BTNF-/- mice, which was significantly decreased in the expression of surface markers and co-stimulatory molecules. Moreover, mice that produced low antibody levels were not able to control infection, therefore progressed to disease; providing direct evidence for the TNF gene-regulating humoral immunity during central nervous system (CNS) M. tuberculosis infection. In contrast, BTNF-/- mice controlled the infection and had levels of IgA, IgG, and IgM comparable to TNFf/f mice.Conclusion: Together, our results demonstrate that TNF may serve as an essential regulator of antibody-mediated immune responses in CNS TB. However, the protective level exhibited by TNF-producing B cells could be defined as baseline protection that could be used in the development of new therapeutic targets or designing new vaccines.

Sandip Patil,1,2 Xiaorong Liu,2 Hongyu Chen,3 Ngiambudulu M Francisco,4 Feiqiu Wen,1,2 Yixin Chen5,6 1Department of Haematology and Oncology, Shenzhen Children’s Hospital, Shenzhen, Guangdong, 518038, People’s Republic of China; 2Paediatric Research Institute, Shenzhen Children’s Hospital, Shenzhen, Guangdong, 518038, People’s Republic of China; 3Department of Laboratory Medicine, Shenzhen Children’s Hospital, Shenzhen, Guangdong, 518038, People’s Republic of China; 4Grupo de Investigação Microbiana e Imunológica, Instituto Nacional de Investigação em Saúde (National Institute for Health Research), Luanda, 3635, Angola; 5Department of Oncology, Shenzhen People’s Hospital, The Second Clinical Medical College, Jinan University, Shenzhen, Guangdong, 518000, People’s Republic of China; 6Department of Oncology, The First Affiliated Hospital, Southern University of Sciences and Technology, Shenzhen, Guangdong, 518000, People’s Republic of ChinaCorrespondence: Yixin Chen, Department of Oncology, Shenzhen People’s Hospital, The Second Clinical Medical College, Jinan University, Guangdong, 518000, People’s Republic of China, Fax +86 755-22942763 Email yixinchen2013@126.comBackground: Since 2015, plasmid-borne mcr-1 has been reported in various bacterial strains in the clinical setting globally. However, the transmission mechanisms of this gene in Salmonella are not well defined. This study aimed to characterize the genomic features of a Salmonella enterica ST34 isolate, which carried a mcr-1, mapped to a carbapenemase and extended spectrum β-lactamase encoding gene located on the IncX4 plasmid.Methods: Salmonella enterica was recovered from a diarrheal paediatric patient in Shenzhen, China. Antimicrobial susceptibility testing was performed by using the VITEK 2 system. Drug resistance genes were identified using targeted primers and Sanger sequencing. The transferability and genome location of mcr-1 was determined by performing conjugation, S1-PFGE and Southern blot hybridization analysis. WGS was performed by Illumina MiSeq sequencing and was assembled using the A5-Miseq pipeline, and gene annotation was performed using RAST 2.0. The database Centre for Genomic Epidemiology’s website was used to identify resistance genes and sequence types (STs).Results: We found that the isolate was extensively drug resistant and belonging to ST34, carrying an IncX4 plasmid with mcr-1, blaKPC-2 and blaCTX-M-15. We also noticed that genes blaPAO, fosA, catB, the mutation in oprD and mexT (MexEF-OprN efflux regulator), and exotoxin-encoding genes (exoS, exoY and exoT) were associated with resistance and virulence in the genome. In addition, heavy metal resistance genes as silP and silE were determined.Conclusion: This study highlights the potential risk of ST34 of Salmonella enterica serotype Typhimurium carrying multiple drug resistance encoding genes in a single IncX4 plasmid.Keywords: Salmonella enterica, MCR-1, KPC-1, CTX-M-15, paediatric patient

An important driving force for precision and individualized medicine is the provision of tailor-made care for patients on an individual basis, in accordance with best evidence practice. Liquid biopsy(LB) has emerged as a critical tool for the early diagnosis of cancer and for treatment monitoring, but its clinical utility for oral squamous cell carcinoma (OSCC) requires more research and validation. Hence, in this review, we have discussed the current applications of LB and the practicality of its routine use in Africa; the potential advantages of LB over the conventional “gold-standard” of tissue biopsy; and finally, practical considerations were discussed in three parts: pre-analytic, analytic processing, and the statistical quality and postprocessing phases. Although it is imperative to establish clinically validated and standardized working guidelines for various aspects of LB sample collection, processing, and analysis for optimal and reliable use, manpower and technological infrastructures may also be an important factor to consider for the routine clinical application of LB for OSCC. LB is poised as a non-invasive precision tool for personalized oral cancer medicine, particularly for OSCC in Africa, when fully embraced. The promising application of different LB approaches using various downstream analyses such as released circulating tumor cells (CTCs), cell free DNA (cfDNA), microRNA (miRNA), messenger RNA (mRNA), and salivary exosomes were discussed. A better understanding of the diagnostic and therapeutic biomarkers of OSCC, using LB applications, would significantly reduce the cost, provide an opportunity for prompt detection and early treatment, and a method to adequately monitor the effectiveness of the therapy for OSCC, which typically presents with ominous prognosis.

Tuberculosis (TB) is a major cause of illness and public health concern, especially in resource-limited countries. This study analyzed the characteristics related to anti-TB drug resistance. Moreover, we examined the evidence-based indications for the treatment of active TB in Angola. This study evaluated the medical records of 176 patients screened for TB from January to September 2016 in Luanda, the capital city of Angola. Approximately 66.5% of the patients were newly diagnosed with active TB. The residence area showed a significant relationship with TB (P = 0.025), whereas age group (P = 0.272), gender (P = 0.853), and HIV status (P = 0.284) did not showed any relationship with TB. Overall, 72.4% of TB patients had resistance to at least one of the anti-TB drugs. The risk of anti-TB drug resistance was higher in males (odds ratio [OR]: 1.22; 95% confidence interval [CI]: 0.42–3.58, P = 0.685] and in TB-HIV coinfected patients [OR: 1.39; (95% CI: 0.26–7.28), P = 0.700], whereas it was lower in patients aged 30 years or older (OR: 0.56; 95% CI: 0.18–1.69) P = 0.303) and in patients living in urbanized areas (OR: 0.74; 95% CI: 0.17–3.25; P = 0.685). Our findings showed that drug-resistant TB is emerging in Angola. Further studies on factors related to anti-TB drug resistance are urgently needed to ascertain the magnitude of the problem and to proffer strategies toward TB control in Angola.

Background Despite the guidelines provided by the World Health Organization for the treatment of malaria, treatment failure occurs in many hospitalized patients. Objective Evaluate whether blood cell count parameters may serve as predictors for malaria treatment. Methodology A cross-sectional study with a quantitative approach. Results Of the 219 patients, 21.5% showed failure to antimalarial treatment, Patient with 21 and 40 years (72.6%), male (53.4%), from peri-urban area (47.5%), with high parasitemia (59.8%), treated with Arthemeter (90.9%) and the mortality were 5.9%. Significant associations were observed between occupation, level of parasitemia and outcome with resistance to antimalarial treatment (p Conclusion The importance of blood cell count parameters in monitoring malaria therapy necessitates the urgent need to re-evaluate Artemether-based therapy. Future studies involving more participants in different settings are needed to provide further evidence.

Since 2015, plasmid-borneWe found that the isolate was extensively drug resistant and belonging to ST34, carrying an IncX4 plasmid withThis study highlights the potential risk of ST34 of

Tackling cancer is a major challenge right on the global level. Europe is only the tip of an iceberg of cancer around the world. Prosperous developed countries share the same problems besetting Europe–and the countries and regions with fewer resources and less propitious conditions are in many cases struggling often heroically against a growing tide of disease. This paper offers a view on these geographically wider, but essentially similar, challenges, and on the prospects for and barriers to better results in this ceaseless battle. A series of panels have been organized by the European Alliance for Personalised Medicine (EAPM) to identify different aspects of cancer care around the globe. There is significant diversity in key issues such as NGS, RWE, molecular diagnostics, and reimbursement in different regions. In all, it leads to disparities in access and diagnostics, patients’ engagement, and efforts for a better understanding of cancer.

Chimeric antigen receptor T cell (CAR-T cell) therapy is a novel adoptive immunotherapy where T lymphocytes are engineered with synthetic receptors known as chimeric antigen receptors (CAR). The CAR-T cell is an effector T cell that recognizes and eliminates specific cancer cells, independent of major histocompatibility complex molecules. The whole procedure of CAR-T cell production is not well understood. The CAR-T cell has been used predominantly in the treatment of hematological malignancies, including acute lymphoblastic leukemia, chronic lymphocytic leukemia, lymphoma, and multiple myeloma. Solid tumors including melanoma, breast cancer and sarcoma offer great promise in CAR-T cell research and development. CD19 CAR-T cell is most commonly used, and other targets, including CD20, CD30, CD38 and CD138 are being studied. Although this novel therapy is promising, there are several disadvantages. In this review we discuss the applications of CAR-T cells in different hematological malignancies, and pave a way for future improvement on the effectiveness and persistence of these adoptive cell therapies., Graphical abstract Chimeric antigen receptor T cells (CAR-T cells) are effector T cells processed from natural T cells by replacing the T cell receptor (TCR) part to CAR part which can recognize and eliminate tumor cells specifically. Their application has been made great progress in hematological malignancies, whereas various difficulties should be overcame in treating solid tumors. This review mainly focuses on the applications of CAR-T cells in different hematological malignancies.fx1

Triggering receptor expressed on myeloid cells 1 (TREM-1) is a receptor mainly expressed on myeloid cells, and it plays an important role in modulating immune response against infectious agents. The function of TREM-1 on nonmyeloid cells such as Vδ2 T cells has not been characterized, and their role in pulmonary tuberculosis (TB) remains unclear. To assess the expression of TREM-1 on blood Vδ2 T cells from pulmonary TB patients and investigate its mechanism of induction, we exploited flow cytometry analysis to study the expression of TREM-1 on Vδ2 T cells from active pulmonary TB patients and control subjects. In this study we demonstrate that TREM-1 (TREM-1+) is highly expressed on Vδ2 T cells of patients with active pulmonary TB. Unlike TREM-1−–expressing Vδ2 T cells, TREM-1+–producing Vδ2 T cells display APC-like phenotypes. Surprisingly, TREM-1+ signaling promotes the Ag-presenting capability of Vδ2 T cells to induce the CD4+ T cell response. TREM-1+Vδ2 T cells induced the proliferation and differentiation of naive CD4+ T cells, as well as the elimination of intracellular mycobacteria. We identified TREM-1+ (but not TREM-1−) as an Ag-presentation amplifier on human blood Vδ2 T cells, and data shed new light on the regulation of Vδ2 T cells in the phase of innate and adaptive immune responses against Mycobacterium tuberculosis infection. Targeting TREM-1+Vδ2 T cells may be a promising approach for TB therapy.

Beta-defensins 2 and 3 (BD2 and BD3) are inducible peptides present at the sites of infection, and they are well characterized for their antimicrobial activities and immune-regulatory functions. However, no study has thoroughly investigated their immunomodulatory effects on macrophage-mediated immune responses against Pseudomonas aeruginosa (PA). Here, we use THP-1 and RAW264.7 cell lines and demonstrate that BD2 and BD3 suppressed macrophage autophagy but enhanced the engulfment of PA and Zymosan bioparticles as well as the formation of phagolysosomes, using immunofluorescence staining and confocal microscopy. Plate count assay showed that macrophage-mediated phagocytosis and intracellular killing of PA were promoted by BD2 and BD3. Furthermore, microarray and real-time PCR showed that the expression of two genes, early growth response gene-1 (EGR1) and c-FOS, was attenuated by BD2 and BD3. Western blot revealed that BD2 and BD3 inhibited the expression and nuclear translocation of EGR1 and c-FOS. Knockdown of EGR1 and c-FOS by siRNA transfection suppressed macrophage autophagy before and after PA infection; while overexpression of these two transcription factors enhanced autophagy but reversed the role of BD2 and BD3 on macrophage-mediated PA eradication. Together, these results demonstrate a novel immune defense activity of BD2 and BD3, which promotes clearance of PA by inhibiting macrophage autophagy through downregulation of EGR1 and c-FOS.

Triggering receptor expressed on myeloid cells 1 (TREM-1) is a receptor mainly expressed on myeloid cells, and it plays an important role in modulating immune response against infectious agents. The function of TREM-1 on nonmyeloid cells such as Vδ2 T cells has not been characterized, and their role in pulmonary tuberculosis (TB) remains unclear. To assess the expression of TREM-1 on blood Vδ2 T cells from pulmonary TB patients and investigate its mechanism of induction, we exploited flow cytometry analysis to study the expression of TREM-1 on Vδ2 T cells from active pulmonary TB patients and control subjects. In this study we demonstrate that TREM-1 (TREM-1

Summary Objective We validated the accuracy of host selected signature gene set using unstimulated whole blood (WB), and peripheral blood mononuclear cells (PBMC) in the diagnosis of tuberculosis (TB). Methods The unstimulated WB and PBMC from 1417 individuals with active pulmonary TB patients, other lung diseases and healthy participants were analyzed using real time polymerase chain reaction (RT-PCR). Results The WB cohort test demonstrates that the combination of GBP5 and KLF2 can differentiate active TB versus HC with sensitivity and specificity of 77.8% and 87.1%, respectively; but most importantly active TB versus OD with sensitivity and specificity of 96.1% and 85.2%, respectively. Again during treatment course, the TB score of GBP5 and KLF2 , analytes secretion and clinical parameters were found to be associated in disease progression. In the PBMC cohort test, we found that the only and best discriminatory combination was GBP5 , DUSP3 and KLF2 inthe active TB versus HC with a sensitivity and specificity of 76.4% and 85.9%, respectively. Conclusions Our study reveals that GBP5 and KLF2 may be useful as a diagnostic tool for active TB, also the two-gene set may serve as surrogate biomarkers for monitoring TB therapy.

Tuberculosis of the central nervous system (CNS-TB) is a devastating complication of tuberculosis, and tumor necrosis factor (TNF) is crucial for innate immunity and controlling the infection. TNF is produced by many cell types upon activation, in particularly the myeloid and T cells during neuroinflammation. Here we used mice with TNF ablation targeted to myeloid and T cell (MT-TNF−/−) to assess the contribution of myeloid and T cell-derived TNF in immune responses during CNS-TB. These mice exhibited impaired innate immunity and high susceptibility to cerebral Mycobacterium tuberculosis infection, a similar phenotype to complete TNF-deficient mice. Further, MT-TNF−/− mice were not able to control T cell responses and cytokine/chemokine production. Thus, our data suggested that collective TNF production by both myeloid and T cells are required to provide overall protective immunity against CNS-TB infection.

Mycobacterium tuberculosis infection of the central nervous system is thought to be initiated once the bacilli have breached the blood brain barrier and are phagocytosed, primarily by microglial cells. In this study, the interactions of M. tuberculosis with neurons in vitro and in vivo were investigated. The data obtained demonstrate that neurons can act as host cells for M. tuberculosis . M. tuberculosis bacilli were internalized by murine neuronal cultured cells in a time-dependent manner after exposure, with superior uptake by HT22 cells compared to Neuro-2a cells (17.7% versus 9.8%). Internalization of M. tuberculosis bacilli by human SK-N-SH cultured neurons suggested the clinical relevance of the findings. Moreover, primary murine hippocampus-derived neuronal cultures could similarly internalize M. tuberculosis . Internalized M. tuberculosis bacilli represented a productive infection with retention of bacterial viability and replicative potential, increasing 2- to 4-fold within 48 h. M. tuberculosis bacillus infection of neurons was confirmed in vivo in the brains of C57BL/6 mice after intracerebral challenge. This study, therefore, demonstrates neurons as potential new target cells for M. tuberculosis within the central nervous system.