Tuberculosis (TB) infection, caused by the airborne pathogen Mycobacterium tuberculosis ( M . tb ), resulted in almost 1.4 million deaths in 2019 and the number of deaths is predicted to increase by 20% over the next 5 years due to the COVID-19 pandemic. Upon reaching the alveolar space, M . tb comes in close contact with the lung mucosa before and after its encounter with host alveolar compartment cells. Our previous studies show that homeostatic innate soluble components of the alveolar lining fluid (ALF) can quickly alter the cell envelope surface of M . tb upon contact, defining subsequent M . tb -host cell interactions and infection outcomes in vitro and in vivo . We also demonstrated that ALF from 60+ year old elders (E-ALF) vs . healthy 18- to 45-year-old adults (A-ALF) is dysfunctional with loss of homeostatic capacity and impaired innate soluble responses linked to high local oxidative stress. In this study, a targeted transcriptional assay demonstrates that M . tb exposure to human ALF alters the expression of its cell envelope genes. Specifically, our results indicate that A-ALF-exposed M . tb upregulates cell envelope genes associated with lipid, carbohydrate, and amino acid metabolism, as well as genes associated with redox homeostasis and transcriptional regulators. Conversely, M . tb exposure to E-ALF shows lesser transcriptional response, with most of the M . tb genes unchanged or downregulated. Overall, this study indicates that M . tb responds and adapts to the lung alveolar environment upon contact, and that the host ALF status determined by factors such as age might play an important role in determining infection outcome.

The Mexican state of Tamaulipas serves as a migration waypoint into the US. Here, we determined the contribution of immigrants to TB burden in Tamaulipas. TB surveillance data from Tamaulipas (2006-2013) was used to conduct a cross-sectional characterization of TB immigrants (born outside Tamaulipas) and identify their association with TB treatment outcomes. Immigrants comprised 30.8% of TB patients, with > 99% originating from internal Mexican migration. Most migration was from South to North, with cities adjacent to the US border as destinations. Immigrants had higher odds of risk factors for TB [older age (≥ 65 year old, OR 2.4, 95% CI 2.1, 2.8), low education (OR 1.3, 95% CI 1.2, 1.4), diabetes (OR 1.2, 95% CI 1.1, 1.4)], or abandoning treatment (adjusted OR 1.2, 95% CI 1.0, 1.5). There is a need to identify strategies to prevent TB more effectively in Tamaulipas, a Mexican migration waypoint.

The Mycobacterium bovis Bacillus Calmette et Guérin (BCG) vaccine was generated in 1921 with the efforts of a team of investigators, Albert Calmette and Camille Guérin, dedicated to the determination to develop a vaccine against active tuberculosis (TB) disease. Since then, BCG vaccination is used globally for protection against childhood and disseminated TB; however, its efficacy at protecting against pulmonary TB in adult and aging populations is highly variable. Due to the BCG generated immunity, this vaccine later proved to have an antitumor activity; though the standing mechanisms behind are still unclear. Recent studies indicate that both innate and adaptive cell responses may play an important role in BCG eradication and prevention of bladder cancer. Thus, cells such as natural killer (NK) cells, macrophages, dendritic cells, neutrophils but also MHC-restricted CD4 and CD8 T cells and γδ T cells may play an important role and can be one the main effectors in BCG therapy. Here, we discuss the role of BCG therapy in bladder cancer and other cancers, including current strategies and their impact on the generation and sustainability of protective antitumor immunity against bladder cancer.

BACKGROUND: The coronavirus disease 2019 pandemic is predicted to have a net negative effect on tuberculosis control, with an estimated excess of 6.3 million tuberculosis cases and 1.4 million deaths by 2025. Programmatic issues such as the lockdown of tuberculosis services affect all patients, while biosocial factors have a differential impact on an individual's risk for tuberculosis or adverse tuberculosis outcomes.

CASE PRESENTATION: We report three Hispanic cases of incident tuberculosis (two males, 43 and 44 years old; one female, 49 years old) after resolution of coronavirus disease episodes. Coincidentally, all cases shared a common risk factor: a chronic history poorly controlled diabetes.

CONCLUSIONS: Our findings alert to the threat posed by the synergy between coronavirus disease and diabetes, on tuberculosis reactivation. In medium- to high-risk settings for tuberculosis, we recommend implementation of routine screening for latent tuberculosis infection in these cases, and preventive tuberculosis treatment in those who are positive.

Bovine tuberculosis (BTB) testing in cattle requires a significant investment of time, equipment, and labor. Novel, rapid, cheaper and accurate methods are needed. The Alere Determine TB lipoarabinomannan antigen (LAM-test) is a World Health Organization-endorsed point-of-care urine test designed to detect active TB disease in humans. The Lionex Animal TB Rapid Test (Lionex-test) is a novel animal specific TB diagnostic blood test. An animal level analysis was performed using urine (n = 141) and milk (n = 63) samples from depopulated BTB-suspected cattle to test the accuracy of the LAM-test when compared to results of positive TB detection by any routine BTB tests (BOVIGAM, necropsy, histology, culture, PCR) that are regularly performed by the United States Department of Agriculture (USDA). The agreement between the urine LAM-test and USDA standard tests were poor at varying testing time points. The same milk samples did not elicit statistically significant agreement with the Lionex-test, although positive trends were present. Hence, we cannot recommend the LAM-test as a valid BTB diagnostic test in cattle using either urine or milk. The Lionex-test's production of positive trends using milk samples suggests larger sample sizes may validate the Lionex-test in accurately diagnosing BTB in cattle using milk samples, potentially providing a quick and reliable field test for BTB.

Aberrant NLRP3 inflammasome activation contributes to the development of endotoxemia. The importance of negative regulation of NLRP3 inflammasomes remains poorly understood. Here, we show that the E3 ubiquitin ligase Cbl-b is essential for preventing endotoxemia induced by a sub-lethal dose of LPS via a caspase-11/NLRP3-dependent manner. Further studies show that NLRP3 undergoes both K63- and K48-linked polyubiquitination. Cbl-b binds to the K63-ubiquitin chains attached to the NLRP3 leucine-rich repeat domain (LRR) via its ubiquitin-associated region (UBA) and then targets NLRP3 at K496 for K48-linked ubiquitination and proteasome-mediated degradation. We also identify RNF125 as an additional E3 ubiquitin ligase that initiates K63-linked ubiquitination of the NLRP3 LRR domain. Therefore, NLRP3 is sequentially ubiquitinated by K63- and K48-linked ubiquitination, thus keeping the NLRP3 inflammasomes in check and restraining endotoxemia.

BACKGROUND: Appropriate technology tests are needed for Mycobacterium tuberculosis drug-susceptibility testing (DST) in resource-constrained settings. This study was performed to evaluate the MDR/XDR-TB Colour Test (a colour platethin-layer agar test; TB-CX) for M. tuberculosis DST by directly testing sputum at University of Gondar Hospital.

METHODS: Sputum samples were each divided into two aliquots. One aliquot was mixed with disinfectant and applied directly to the TB-CX quadrant petri-plate containing culture medium with and without isoniazid, rifampicin, or ciprofloxacin. Concurrently, the other aliquot was decontaminated with sodium hydroxide, centrifuged, and cultured on Lӧwenstein-Jensen medium; the stored M. tuberculosis isolates were then sub-cultured in BACTEC Mycobacteria Growth Indicator Tube (MGIT) 960 for reference DST.

RESULTS: The TB-CX test yielded DST results for 94% (123/131) of positive samples. For paired DST results, the median number of days from sputum processing to DST was 12 for TB-CX versus 35 for LJ-MGIT (p<0.001). Compared with LJ-MGIT for isoniazid, rifampicin, and multidrug-resistant tuberculosis, TB-CX had 59%, 96%, and 95% sensitivity; 96%, 94%, and 98% specificity; and 85%, 94%, and 98% agreement, respectively. All ciprofloxacin DST results were susceptible by both methods.

CONCLUSION: The TB-CX test was simple and rapid for M. tuberculosis DST. Discordant DST results may have resulted from sub-optimal storage and different isoniazid concentrations used in TB-CX versus the reference standard test.

Mycobacterium tuberculosis (Mtb) is the causative agent of the infectious disease tuberculosis (TB), which is a leading cause of death worldwide. Approximately one fourth of the world's population is infected with Mtb. A major unresolved question is delineating the inducers of protective long-lasting immune response without inducing overt, lung inflammation. Previous studies have shown that the presence of inducible Bronchus-Associated Lymphoid Tissue (iBALT) correlate with protection from Mtb infection. In this study, we hypothesized that specific Mtb factors could influence the formation of iBALT, thus skewing the outcome of TB disease. We infected non-human primates (NHPs) with a transposon mutant library of Mtb, and identified specific Mtb mutants that were over-represented within iBALT-containing granulomas. A major pathway reflected in these mutants was Mtb cell wall lipid transport and metabolism. We mechanistically addressed the function of one such Mtb mutant lacking mycobacteria membrane protein large 7 (MmpL7), which transports phthiocerol dimycocerosate (PDIM) to the mycobacterial outer membrane (MOM). Accordingly, murine aerosol infection with the Mtb mutant Δmmpl7 correlated with increased iBALT-containing granulomas. Our studies showed that the Δmmpl7 mutant lacking PDIMs on the surface overexpressed diacyl trehaloses (DATs) in the cell wall, which altered the cytokine/chemokine production of epithelial and myeloid cells, thus leading to a dampened inflammatory response. Thus, this study describes an Mtb specific factor that participates in the induction of iBALT formation during TB by directly modulating cytokine and chemokine production in host cells.

Vaccine and antiviral development against SARS-CoV-2 infection or COVID-19 disease would benefit from validated small animal models. Here, we show that transgenic mice expressing human angiotensin-converting enzyme 2 (hACE2) by the human cytokeratin 18 promoter (K18 hACE2) represent a susceptible rodent model. K18 hACE2 transgenic mice succumbed to SARS-CoV-2 infection by day 6, with virus detected in lung airway epithelium and brain. K18 ACE2 transgenic mice produced a modest TH1/2/17 cytokine storm in the lung and spleen that peaked by day 2, and an extended chemokine storm that was detected in both lungs and brain. This chemokine storm was also detected in the brain at day 6. K18 hACE2 transgenic mice are, therefore, highly susceptible to SARS-CoV-2 infection and represent a suitable animal model for the study of viral pathogenesis, and for identification and characterization of vaccines (prophylactic) and antivirals (therapeutics) for SARS-CoV-2 infection and associated severe COVID-19 disease.