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Influenza pandemic of the human lung was caused by the Influenza A (H1N1) over 100 years ago in 1918, but it recurred in pandemic fashion in 2009. Understanding the pathobiology of this infectious agent in the human lung could lead to adjuvant therapies that are relatively non-toxic and reduce the mortality of the human host. Overall, our objective was to apply morphoproteomics to pulmonary lung sections from an autopsied victim so that we may better define its biology from the perspective of its interaction with the host and provide options for therapeutic targets.Morphoproteomic analysis from a case study of this Influenza A (H1N1) pulmonary infection included immunohistochemical probes to detect the expressions of fatty acid synthase (FAS), CD163Representative sections of the Influenza A (H1N1) victim's lung showed: cytoplasmic expression of FAS in most of the sloughed and atypical alveolar pneumocytes; abundance of intra-alveolar and alveolar interstitial CD163Morphoproteomics and microanatomical features coincide with the etiopathogenic features of pulmonary Influenza A (H1N1) infection and the host response. This plus data mining of the medical literature suggests that adjunctive, targeted therapy such as metformin and vitamin D3 could address the biology of Influenza A (H1N1) pneumonia, enhance the host immune response, and prevent its progression to a life-threatening, ventilator-dependent clinical situation.

Rationale: Our current understanding of tuberculosis (TB) pathophysiology is limited by a reliance on animal models, the paucity of human TB lung tissue, and traditional histopathological analysis, a destructive two-dimensional approach that provides limited spatial insight. Determining the three-dimensional (3D) structure of the necrotic granuloma, a characteristic feature of TB, will more accurately inform preventive TB strategies. Objectives: To ascertain the 3D shape of the human tuberculous granuloma and its spatial relationship with airways and vasculature within large lung tissues. Methods: We characterized the 3D microanatomical environment of human tuberculous lungs by using micro computed tomography, histopathology, and immunohistochemistry. By using 3D segmentation software, we accurately reconstructed TB granulomas, vasculature, and airways in three dimensions and confirmed our findings by using histopathology and immunohistochemistry. Measurements and Main Results: We observed marked heterogeneity in the morphology, volume, and number of TB granulomas in human lung sections. Unlike depictions of granulomas as simple spherical structures, human necrotic granulomas exhibit complex, cylindrical, branched morphologies that are connected to the airways and shaped by the bronchi. The use of 3D imaging of human TB lung sections provides unanticipated insight into the spatial organization of TB granulomas in relation to the airways and vasculature. Conclusions: Our findings highlight the likelihood that a single, structurally complex lesion could be mistakenly viewed as multiple independent lesions when evaluated in two dimensions. In addition, the lack of vascularization within obstructed bronchi establishes a paradigm for antimycobacterial drug tolerance. Lastly, our results suggest that bronchogenic spread of Mycobacterium tuberculosis reseeds the lung.

Our current understanding of the spectrum of TB and COVID-19 lesions in the human lung is limited by a reliance on low-resolution imaging platforms that cannot provide accurate 3D representations of lesion types within the context of the whole lung. To characterize TB and COVID-19 lesions in 3D, we applied micro/nanocomputed tomography to surgically resected, postmortem, and paraffin-embedded human lung tissue. We define a spectrum of TB pathologies, including cavitary lesions, calcium deposits outside and inside necrotic granulomas and mycetomas, and vascular rearrangement. We identified an unusual spatial arrangement of vasculature within an entire COVID-19 lobe, and 3D segmentation of blood vessels revealed microangiopathy associated with hemorrhage. Notably, segmentation of pathological anomalies reveals hidden pathological structures that might otherwise be disregarded, demonstrating a powerful method to visualize pathologies in 3D in TB lung tissue and whole COVID-19 lobes. These findings provide unexpected new insight into the spatial organization of the spectrum of TB and COVID-19 lesions within the framework of the entire lung.

Tuberculosis (TB) in humans is characterized by formation of immune-rich granulomas in infected tissues, the architecture and composition of which are thought to affect disease outcome. However, our understanding of the spatial relationships that control human granulomas is limited. Here, we used multiplexed ion beam imaging by time of flight (MIBI-TOF) to image 37 proteins in tissues from patients with active TB. We constructed a comprehensive atlas that maps 19 cell subsets across 8 spatial microenvironments. This atlas shows an IFN-γ-depleted microenvironment enriched for TGF-β, regulatory T cells and IDO1+ PD-L1+ myeloid cells. In a further transcriptomic meta-analysis of peripheral blood from patients with TB, immunoregulatory trends mirror those identified by granuloma imaging. Notably, PD-L1 expression is associated with progression to active TB and treatment response. These data indicate that in TB granulomas, there are local spatially coordinated immunoregulatory programs with systemic manifestations that define active TB.

Mycobacterium bovis BCG is widely used as a vaccine against tuberculosis due to M. tuberculosis (Mtb), which kills millions of people each year. BCG variably protects children, but not adults against tuberculosis. BCG evades phagosome maturation, autophagy, and reduces MHC-II expression of antigen-presenting cells (APCs) affecting T-cell activation. To bypass these defects, an autophagy-inducing, TLR-2 activating C5 peptide from Mtb-derived CFP-10 protein was overexpressed in BCG in combination with Ag85B. Recombinant BCG85C5 induced a robust MHC-II-dependent antigen presentation to CD4 T cells in vitro, and elicited stronger TH1 cytokines (IL-12, IL-1β, and TNFα) from APCs of C57Bl/6 mice increasing phosphorylation of p38MAPK and ERK. BCG85C5 also enhanced MHC-II surface expression of MΦs by inhibiting MARCH1 ubiquitin ligase that degrades MHC-II. BCG85C5 infected APCs from MyD88 or TLR-2 knockout mice showed decreased antigen presentation. Furthermore, BCG85C5 induced LC3-dependent autophagy in macrophages increasing antigen presentation. Consistent with in vitro effects, BCG85C5 markedly expanded both effector and central memory T cells in C57Bl/6 mice protecting them against both primary aerosol infection with Mtb and reinfection, but was less effective among TLR-2 knockout mice. Thus, BCG85C5 induces stronger and longer lasting immunity, and is better than BCG against tuberculosis of mice., Tuberculosis: Recombinant BCG vaccine shows enhanced protection via more efficient presentation The BCG vaccine is widely used but has highly variable efficacy due at least in part to its inefficient processing by antigen-presenting cells (APC). Chinnaswamy Jagannath and colleagues at the University of Texas Health Sciences Center identify a peptide (C5) derived from the Mycobacterium tuberculosis (Mtb) virulence factor component CFP10 which can efficiently enhance BCG’s ability to activate APC function. C5’s activity in APCs is dependent on both Toll-like receptor 2 signaling and activation of autophagy which together enhances presentation of the Mtb protein Ag85B. A recombinant BCG vaccine over-expressing both Ag85B and C5 (BCG85C5) more strongly activates TH1-like responses which are known to be protective against Mtb infection. Mouse vaccination with BCG85C5 induces a qualitatively and quantitatively superior response to BCG—including greater expansion of Ag85B-specific T cells, more robust memory T cell formation and better control of Mtb in both lung and spleen.

Macrophages are the primary host cells for Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), during its intracellular survival in humans. The pathogen has a remarkable capacity to survive within the hostile environment of macrophages. However, primary infection does not result in active TB disease in most individuals. The majority of individuals remain latently infected, wherein the bacteria are held in check by the host immune response. Nevertheless, such individuals can develop active TB later upon the decline in their immune status. In contrast, in a small fraction of infected individuals, the host immune response fails to control the growth of M. tuberculosis bacilli, and granulomatous TB develops progressively. Elucidating the molecular and phenotypic events that govern the outcome of the infection within macrophages is fundamental to understanding the key features of these cells that could be equally critical in infection control. The molecular details of the M. tuberculosis-macrophage interaction continue to be discerned, and emerging evidence suggests that macrophage population that participate in infection is heterogeneous. While the local environment and developmental origin could influence the phenotypic heterogeneity and functional plasticity of macrophages, M. tuberculosis has also been demonstrated to modulate the polarization of macrophages. In this review, we draw on work investigating specialized macrophage populations and their interactions with M. tuberculosis with respect to pathogenesis and specific immune responses. Understanding the mechanisms that control the repertoire of macrophage phenotypes and behaviors during infection may provide prospects for novel TB control strategies through modulation of immunobiological functions of macrophages.

Combined chemotherapy with temozolomide (TMZ), bevacizumab (BEV) and irinotecan (IRI) [TBI] has been used in patients with recurrent or progressive high-grade gliomas. Patients tolerated the regimen well with increased frequency of reversible clinical myelosuppression (CM), hypertension and proteinuria. However, organ-specific toxicities have never been evaluated by post-mortem examination. From 2009 to 2019, post-mortem examinations were performed in seventy-six decedents, including gliomas (N=68, 44/M and 24/F, median age: 59, ranging 23–80 years old) and brain metastases (N=8, 5/M and 3/F, ranging 39–75 years old). Twenty-four glioma subjects were treated with 1–25 cycles TBI (median 5.5) at glioma recurrence. All subjects’ clinical information, treatment histories and adverse events were collected. Five (7.7%, 5/65) glioma decedents (excluding three glioma patients who never received TMZ) permanently discontinued TMZ due to severe CM during concurrent chemoradiation therapy. There is no significantly elevated severity of CM from TBI when compared to standard of care therapies, nor when comparing extended TMZ treatment to the standard 12 cycles of TMZ. However, exposure to IRI significantly increased the CM occurrence (p< 0.05). Among glioma decedents, the most common cause of death was tumor progression (63.2 %, N=43), followed by aspiration pneumonia (48.5%, N=33). No deaths were attributed to acute toxicity from TBI. An electromicroscopic (EM) examination was performed in addition to routine autopsy procedures to investigate the cause of hypertension and proteinuria frequently developing in patients received BEV therapy. Ultrastructural evidence of thrombotic microangiopathy was observed in the kidneys among BEV users; however, it is difficult to conclude such changes were related to BEV due to rapid autolytic changes and artifacts. CONCLUSION: IRI, not the extended use of TMZ, significantly increased the frequency of reversible CM in recurrent glioma patients. There are no unexpected adverse events or organ-specific toxicities detected among glioma decedents who received the TBI regimen.

Post-primary tuberculosis (TB) disease is characterized by paucibacillary necrosis of the early lesion, tuberculous pneumonia, in the adult human lung. The mechanism is speculated to be a strong localized delayed type hypersensitive response (DTH). However, up to this date, no one has been able to identify the source of the large accumulation of MTB antigens required for the DTH response. Although it is known and accepted that the pathogen

The COVID-19 pandemic has challenged the world economically and medically. Understanding and defining the biology of this specific coronavirus infection may lead to targeted therapies to lessen its virulence and expand the host resistance. This study's objective was to apply morphoproteomics to pulmonary lung sections from a forensic autopsy of an untreated COVID-19 victim, so that we may better define its biology from the perspective of its interaction with the host and provide options for therapeutic targets.Morphoproteomic analysis from a case study of this COVID-19 pulmonary infection included immunohistochemical probes to detect phosphorylated p-STAT3 (Tyr 705), as part of the interleukin (IL)-6 pathway; cyclooxygenase (COX)-2, CD8+ cytotoxic lymphocytes, Programmed Death (PD)-1 receptor+ lymphoid cells, CD56+ NK lymphoid cells, CD163+ (M2 polarized monocytes/macrophages), and programmed death-ligand 1 (PD-L1) expression as part of the host response to interaction with the COVID-19 virus.Representative sections of the COVID-19 victim's lung showed: nuclear expression of p-STAT3 (Tyr 705) in many of the alveolar pneumocytes and in occasional endothelial cells; COX-2 expression in the alveolar pneumocytes; a relative paucity of CD8+ cytotoxic lymphocytes; absence of CD56+ NK lymphoid cells; abundance of intra-alveolar and alveolar interstitial CD163+ macrophages/monocytes; PD-L1 expression on occasional macrophages, focally on collections of alveolar pneumocytes, and on cells in the alveolar interstitium; and rare PD-1+ lymphocytes in similar regions as CD8+ lymphocytes.Morphoproteomics and microanatomical features coincide with the etiopathogenic features of pulmonary coronavirus infection and the host response. This suggests that a targeted therapy could address the biology of COVID-19 pneumonia, enhance the host immune response and prevent its progression to a life-threatening, ventilator-dependent clinical situation.

Our current understanding of the pathophysiology of human pulmonary TB is limited by the paucity of human TB lung tissue for study and reliance on 2D analytical methods. Here, to overcome the limitations of conventional 2D histopathology, we used high-resolution 3D X-ray imaging (µCT/nCT) to characterize necrotic lesions within human tuberculous lung tissues in relation to the airways and vasculature. We observed marked heterogeneity in the 3D structure and volume of lesions. Also, 3D imaging of large human TB lung sections provides unanticipated new insight into the spatial organization of TB lesions in relation to airways and the vascular system. Contrary to the current dogma depicting granulomas as simple spherical structures, we show that TB lesions exhibit complex, cylindrical, branched-type morphologies, which are connected to, and shaped by, the small airways. Our results highlight the likelihood that a single structurally complex lesion could be wrongly viewed as multiple independent lesions when evaluated in 2D. These findings have strong implications for understanding the pathophysiology and evolution of TB disease and suggest that aerosolized drug delivery strategies for TB should be reconsidered.

Tuberculosis relapse following drug treatment of active disease is an important global public health problem due to the poorer clinical outcomes and increased risk of drug resistance development. Concurrent infection with HIV, including in those receiving anti-retroviral therapy (ART), is an important risk factor for relapse and expansion of drug resistant Mycobacterium tuberculosis (Mtb) isolates. A greater understanding of the HIV-associated factors driving TB relapse is important for development of interventions that support immune containment and complement drug therapy. We employed the humanized mouse to develop a new model of post-chemotherapy TB relapse in the setting of HIV infection. Paucibacillary TB infection was observed following treatment with Rifampin and Isoniazid and subsequent infection with HIV-1 was associated with increased Mtb burden in the post-drug phase. Organized granulomas were observed during development of acute TB and appeared to resolve following TB drug therapy. At relapse, granulomatous pathology in the lung was infrequent and mycobacteria were most often observed in the interstitium and at sites of diffuse inflammation. Compared to animals with HIV mono-infection, higher viral replication was observed in the lung and liver, but not in the periphery, of animals with post-drug TB relapse. The results demonstrate a potential role for the humanized mouse as an experimental model of TB relapse in the setting of HIV. Long term, the model could facilitate discovery of disease mechanisms and development of clinical interventions.

Mycobacterium tuberculosis (MTB) has long been known to persist in grossly normal tissues even in people with active lesions and granulomas in other parts of the body. We recently reported that post-primary TB begins as an asymptomatic infection that slowly progresses, accumulating materials for a massive necrotizing reaction that results in cavitation. This paper explores the possible roles of trehalose 6,6' dimycolate (TDM) or cord factor in the ability of MTB to persist in such lesions without producing inflammation. TDM is unique in that it has three distinct sets of biologic activities depending on its physical conformation. As a single molecule, TDM stimulates macrophage C-type lectin receptors including Mincle. TDM can also form three crystal like structures, cylindrical micelles, intercalated bilayer and monolayer, that have distinct non receptor driven activities that depend on modulation of interactions with water. In the monolayer form, TDM is highly toxic and destroys cells in minutes upon contact. The cylindrical micelles and an intercalated bilayer have surfaces composed entirely of trehalose which protect MTB from killing in macrophages. Here we review evidence that these trehalose surfaces bind water. We speculate that this immobilized water constituites of an "invisibility cloak" that facilitates the persistence of MTB in multiple cell types without producing inflammation, even in highly immune individuals.

Murine models of Mycobacterium tuberculosis (Mtb) infection demonstrate progression of M1-like (proinflammatory) and M2-like (anti-inflammatory) macrophage morphology following primary granuloma formation. The Mtb cell wall cording factor, trehalose 6,6′-dimycolate (TDM), is a physiologically relevant and useful molecule for modeling early macrophage-mediated events during establishment of the tuberculosis-induced granuloma pathogenesis. Here, it is shown that TDM is a major driver of the early M1-like macrophage response as seen during initiation of the granulomas of primary pathology. Proinflammatory cytokines tumor necrosis factor-α, IL-1β, IL-6, and IL-12p40 are produced in lung tissue after administration of TDM to mice. Furthermore, CD11b(+)CD45(+) macrophages with a high surface expression of the M1-like markers CD38 and CD86 were found present in regions of pathology in lungs of mice at 7 days post-TDM introduction. Conversely, only low phenotypic marker expression of M2-like markers CD206 and EGR-2 were present on macrophages. These findings suggest that TDM plays a role in establishment of the M1-like shift in the microenvironment during primary tuberculosis.

Understanding the biology of the tuberculosis pathogen during dormant asymptomatic infection, called latent tuberculosis is crucial to decipher a resilient therapeutic strategy for the disease. Recent discoveries exhibiting presence of pathogen’s DNA and bacilli in mesenchymal stem cells (MSCs) of human and mouse despite completion of antitubercular therapy, indicates that these specific cells could be one of the niches for dormant Mycobacterium tuberculosis in humans. To determine if in vitro infection of human MSCs could recapitulate the in vivo characteristics of dormant M. tuberculosis, we examined survival, phenotype, and drug susceptibility of the pathogen in MSCs. When a very low multiplicity of infection (1:1) was used, M. tuberculosis could survive in human bone marrow derived MSCs for more than 22 days without any growth. At this low level of infection, the pathogen did not cause any noticeable host cell death. During the later phase of infection, MSC-residing M. tuberculosis exhibited increased expression of HspX (a 16-kDa alpha-crystallin homolog) with a concurrent increase in tolerance to the frontline antitubercular drugs Rifampin and isoniazid. These results present a human MSC-based intracelllular model of M. tuberculosis infection to dissect the mechanisms through which the pathogen acquires and maintains dormancy in the host.

A vaccine that prevents transmission of infection is urgently needed in the fight against tuberculosis (TB). Results of clinical trials have been disappointing. Major problems include lack of biomarkers and understanding of the mechanisms of disease and protection. A more fundamental problem is that the scientific community seldom recognizes that primary and post-primary TB are distinct disease entities. Nearly all vaccine candidates have been designed and tested in models of primary TB, while transmission of infection is mediated by post-primary TB. Post-primary TB is seldom studied because no animal develop complete symptoms of the disease as it exists in humans. Nevertheless, mice, guinea pigs and rabbits all develop infections that at certain points appear to be models of human post-primary TB. Slowly progressive pulmonary TB in immunocompetent mice is an example. It is characterized by an alveolitis with infected foamy macrophages that have multiple characteristics of the human disease. We demonstrated that inclusion of an immune modulating agent, lactoferrin, with a BCG vaccine in this model induced a sustained reduction in lung pathology, but not numbers of organisms in tissue. Since the animals die of expanding pathology, this demonstrates the feasibility of using selected animal models for studies of vaccines against post-primary TB.

Objectives: Harris Health System (HHS) is a safety net system providing health care to the underserved of Harris County, Texas. There was a 6-month waiting period for a rheumatologist consult for patients with suspected systemic lupus erythematosus (SLE). The objective of the intervention was to improve access to specialty care. Methods: An algorithmic approach to testing for SLE was implemented initially through the HHS referral center. The algorithm was further offered as a “one-click” order for physicians, with automated reflex testing, interpretation, and case triaging by clinical pathology. Results: Data review revealed that prior to the intervention, 80% of patients did not have complete laboratory workups available at the first rheumatology visit. Implementation of algorithmic testing and triaging of referrals by pathologists resulted in decreasing the waiting time for a rheumatologist by 50%. Conclusions: Clinical pathology intervention and case triaging can improve access to care in a county health care system.

Human mesenchymal stem cells (MSCs) express scavenger receptors that internalize lipids, including oxidized low-density lipoprotein (oxLDL). We report that MSCs phagocytose Mycobacterium tuberculosis (Mtb) through two types of scavenger receptors (SRs; MARCO and SR-B1), as blockade of the receptors with antibodies or siRNA knockdown decreased the uptake of Mtb. MSCs also expressed mannose receptor (MR) that was found to endocytose rhodamine-labeled mannosylated BSA (rMBSA), though the receptor was not involved in the uptake of Mtb. Dil-oxLDL and rMBSA taken up into MSC endosomes colocalized with Mtb phagosomes, thus suggesting that the latter were fusion competent. Phagocytosed Mtb did not replicate within MSCs, thus suggesting an intrinsic control of bacterial growth. Indeed, MSCs exhibited intrinsic autophagy, which was up-regulated after activation with rapamycin. SiRNA knockdown of autophagy initiator beclin-1 enhanced Mtb survival, whereas rapamycin-induced autophagy increased intracellular killing of Mtb. In addition, MSCs secreted nitric oxide after Mtb infection, and inhibition of NO by N(G)-monomethyl-L-arginine enhanced intracellular survival of Mtb. MSCs can be grown in large numbers in vitro, and autologous MSCs transfused into tuberculosis patients have been found to be safe and improve lung immunity. Thus, MSCs are novel phagocytic cells with a potential for immunotherapy in treating multidrug-resistant tuberculosis.

Objective At our institution, our microbiologist, pharmacist, and infectious disease (ID) team meet to discuss ID patients, and this meeting is referred to as microbiology rounds. We hypothesized that our microbiology rounds reduce antibiotic costs. The study involved a review of 80 patients with an ID consultation order at each of the 3 hospitals: hospital A (HA) (only HA has microbiology rounds), hospital B (HB), and hospital C (HC). Of this population, we included patients with a positive blood culture. Thirty-six patients who met the above criteria were included in the study. The average antibiotic cost/patient/day at HA, HB, and HC were $66.0, $123, and $109, respectively. Also, we found that change in antibiotics was appropriate when compared to the final microbiology results in 90%, 44%, and 40% of the time at HA, HB, and HC, respectively. Herein, we found an association between conducting microbiology rounds and reduction of antibiotic cost.

In an effort to develop more effective therapy for tuberculosis (TB), research efforts are looking towards host directed therapy, reprogramming the body’s natural defenses to better control the infection. While significant progress is being made, the efforts are limited by lack of understanding of the pathology and pathogenesis of adult type TB disease. We have recently published evidence that the developing lesions in human lungs are focal endogenous lipid pneumonia that constitutes a region of local susceptibility in a person with strong systemic immunity. Since most such lesions regress spontaneously, the ability to study them directly with immunohistochemistry provides means to investigate why some progress to clinical disease while others asymptomatically regress. Furthermore, this should enable us to develop more effective host directed therapies. Morphoproteomics has proven to be an effective means of characterizing protein expression that can be used to identify metabolic pathways, which can lead to more effective therapies. The purpose of this perspective will argue that using morphoproteomics on human TB lung tissue is a particularly promising method to direct selection of host directed therapeutics.

Although it is accepted that the environment within the granuloma profoundly affects Mycobacterium tuberculosis (Mtb) and infection outcome, our ability to understand Mtb gene expression in these niches has been limited. We determined intragranulomatous gene expression in human-like lung lesions derived from nonhuman primates with both active tuberculosis (ATB) and latent TB infection (LTBI). We employed a non–laser-based approach to microdissect individual lung lesions and interrogate the global transcriptome of Mtb within granulomas. Mtb genes expressed in classical granulomas with central, caseous necrosis, as well as within the caseum itself, were identified and compared with other Mtb lesions in animals with ATB (n = 7) or LTBI (n = 7). Results were validated using both an oligonucleotide approach and RT-PCR on macaque samples and by using human TB samples. We detected approximately 2,900 and 1,850 statistically significant genes in ATB and LTBI lesions, respectively (linear models for microarray analysis, Bonferroni corrected, P

Tuberculosis (TB) remains a significant public health burden worldwide. Treatment of this disease requires a minimum of six months and there is no vaccine available for the most common form of the disease. Increasing evidence suggests that the mycobacterial glycolipid trehalose 6,6' dimycolate (TDM; cord factor) plays a key role in the pathogenesis of TB disease. TDM protects the TB bacilli from macrophage-mediated killing, inhibits effective antigen presentation, and reduces the formation of protective T-cell responses. TDM promotes initiation of granuloma formation and likely plays a role in caseation. Furthermore, TDM may contribute to the development of post primary disease. Receptors for TDM were recently described and are expected to contribute to our knowledge of the molecular pathogenesis of TB disease. In this manner, understanding TDM may prove promising towards development of targeted TB therapeutics to limit clinical pathologies.

Humans will again set foot on the moon. The moon is covered by a layer of fine dust, which can pose a respiratory hazard. We investigated the pulmonary toxicity of lunar dust in rats exposed to 0, 2.1, 6.8, 20.8 and 60.6 mg/m(3) of respirable-size lunar dust for 4 weeks (6 h/day, 5 days/week); the aerosols in the nose-only exposure chambers were generated from a jet-mill ground preparation of a lunar soil collected during the Apollo 14 mission. After 4 weeks of exposure to air or lunar dust, groups of five rats were euthanized 1 day, 1 week, 4 weeks or 13 weeks after the last exposure for assessment of pulmonary toxicity. Biomarkers of toxicity assessed in bronchoalveolar fluids showed concentration-dependent changes; biomarkers that showed treatment effects were total cell and neutrophil counts, total protein concentrations and cellular enzymes (lactate dehydrogenase, glutamyl transferase and aspartate transaminase). No statistically significant differences in these biomarkers were detected between rats exposed to air and those exposed to the two low concentrations of lunar dust. Dose-dependent histopathology, including inflammation, septal thickening, fibrosis and granulomas, in the lung was observed at the two higher exposure concentrations. No lesions were detected in rats exposed to ≤6.8 mg/m(3). This 4-week exposure study in rats showed that 6.8 mg/m(3) was the highest no-observable-adverse-effect level (NOAEL). These results will be useful for assessing the health risk to humans of exposure to lunar dust, establishing human exposure limits and guiding the design of dust mitigation systems in lunar landers or habitats.

Mesenchymal stem cells (MSCs) are non-hematopoietic cells that occur in almost all human tissues and can be cultured and expanded to large numbers in vitro. They secrete growth factors, cytokines, and chemokines and express Toll-like receptors on their surface, although multiple cell biological mechanisms remain unclear. MSCs are multi-potent and can differentiate into many cell types including adipocytes, neuronal cells and osteoclasts. Despite gaps in cell biology, because of their immunomodulatory and regenerative capacity, several hundred clinical trials have used MSCs for therapy of cancer, autoimmune diseases and control of inflammation during organ transplantation. MSCs secrete immune-modulatory factors and are able to skew T cell responses and shift M1 to M2 differentiation of macrophages. We review the emerging role of MSCs to act as phagocytes for Mycobacterium tuberculosis and its role during the persistence of M. tuberculosis and spread of infection. Paradoxically, MSCs use innate defense mechanisms of autophagy and nitric oxide to inhibit the growth of intracellular M. tuberculosis. In addition, transplantation with autologous MSCs improved the clinical condition of patients with multi-drug resistant tuberculosis. Thus, in addition to the well-known immune defense played by macrophages, DCs, classical T cells and non-classical immune cells, MSCs have emerged as a fifth element capable of regulating immune responses during tuberculosis. We discuss their immunomodulatory properties and innate defense mechanisms in the context of developing immunotherapeutic strategies for tuberculosis.

Trehalose 6,6'dimycolate (TDM) is a glycolipid found in nearly pure form on the surface of virulent Mycobacterium tuberculosis (MTB). This manuscript investigated the production of TDM, growth rate and colony morphology of multiple strains of MTB, each of which had been isolated from both pulmonary (sputum) and extrapulmonary sites of multiple patients. Since sputum contains MTB primarily from cavities and extrapulmonary biopsies are typically granulomas, this provided an opportunity to compare the behavior of single strains of MTB that had been isolated from cavities and granulomas. The results demonstrated that MTB isolated from pulmonary sites produced more TDM (3.23 ± 1.75 μg TDM/mg MTB), grew more rapidly as thin spreading pellicles, demonstrated early cording, and climbed culture well walls. In contrast, extrapulmonary isolates produced less TDM (1.42 ± 0.58 μg TDM/mg MTB) (p

Cavernous angioma is one of several vascular malformations whose presentation is usually seizures, headaches, or neurological deficits. The frequency of such malformations is controversial and appears to be more common than once thought because of the availability of magnetic resonance imaging (MRI). A 16-year-old presented to an emergency department with the complaint of headaches and oral numbness. She was found to have mild dysarthria and right-sided hemiparesis. Computed tomography (CT) scan of the head revealed a large hemorrhage present in the left posterior frontal region with two smaller lesions in the vertebral hemispheres. MRI later confirmed the lesions to be compatible with cavernous angioma. The mother also complained of having a long history of headaches with numbness in her hands but had a negative CT scan. This raises the question of familial pattern, which has been well documented in the literature. A review of the literature looking at etiology, differential diagnosis, and management options is included.

The purpose of this study was to determine whether the influence of environmental, economic, and insurance barriers affect the immunization process for adolescents. The study attempted to determine whether physician knowledge was positively associated with the implementation of vaccinations to adolescent patients. This study used a mixed methods through the gathering of data via a survey that included both qualitative and quantitative components. Study respondents were recruited from a generated list of primary care physicians obtained through the Ohio Osteopathic Association; 232 physicians participated in this study. The survey questions assessed current practices and beliefs regarding immunizations as well as their attitude toward vaccination. Data measured included frequency of response; the categorical variables were compared using a chi-square method of statistical analysis. Statistical significance was set at p

Summary Healthcare is a critical issue in our nation. This information was presented to the United States Senate on July 14, 2009. This is a study of the literature concerning Health ER. Barriers and incentives are explored and represented in charts and graphs to indicate the cost of the essential technology to improve record keeping and healthcare. Barriers and incentives are explored and represented in charts and graphs to indicate the cost of the essential technology which will improve record keeping and healthcare. This must be cost effective for the provider and allow records to be accessed in a manner that will not jeopardize patient confidentiality.

The immune system responds to tuberculosis (TB) infection by forming granulomas. However, subsequent immune-mediated destruction of lung tissue is a cause of significant morbidity and contributes to disease transmission. Lactoferrin, an iron-binding glycoprotein, has demonstrated immunomodulatory properties that decrease tissue destruction and promote T(H)1 immune responses, both of which are essential for controlling TB infection. The cord factor trehalose 6,6'-dimycolate (TDM) model of granuloma formation mimics many aspects of TB infection with a similar histopathology accompanied by proinflammatory cytokine production. C57BL/6 mice were injected intravenously with TDM. A subset of mice was given 1 mg of bovine lactoferrin 24 h post-TDM challenge. Lung tissue was analyzed for histological response and for the production of proinflammatory mediators. C57BL/6 mice demonstrated a granuloma formation that correlated with an increased production of interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α,) IL-12p40, interferon-gamma (IFN-γ), and IL-10 protein. Mice treated with lactoferrin postchallenge had significantly fewer and smaller granulomas compared with those given TDM alone. Proinflammatory and T(H)1 cytokines essential to the control of mycobacterial infections, such as TNF-α and IFN-γ, were not significantly different in mice treated with lactoferrin. Furthermore, the anti-inflammatory cytokines IL-10 and transforming growth factor-β were increased. A potential mechanism for decreased tissue damage observed in the lactoferrin-treated mice is proposed. Because of its influence to modulate immune responses, lactoferrin may be a useful adjunct in the treatment of granulomatous inflammation occurring during mycobacterial infection.

Human Adenovirus (HAdv) vectors expressing Mycobacterium tuberculosis (Mtb) derived antigens, have been tested as candidate boosters for BCG vaccine in animal models and Phase I human studies but failed to provide significant additional protection. Presumably, pre-existing immunity to HAdv among humans has been suggested to limit their efficacy as vectors. We earlier reported that novel bovine adenovirus (BAdv)-vectors induced robust T cell mediated immunity in mice and carried less risk of interference by human innate immunity. Thus, we evaluated BAdv vectors expressing Mtb derived antigen 85B and a novel TLR-2 activating peptide as booster vaccines for BCG in vitro and in mouse model for tuberculosis. Both mouse and human APCs (macrophages and dendritic cells) infected with BAdv-85B showed robust presentation of p25 epitope to T cells within 18 hrs of infection. BAdv-Ag85B-TLR2 was better than BAdv-85B in inducing antigen presentation. Antigen presentation by both BAdv-Ag85B and BAdv-Ag85B-TLR2 peptide were significantly decreased when DCs were derived from atg7 knockout mice or when 3-methyladenine was used for blockade, indicating that autophagy played a role during adenovirus-induced antigen presentation. Consistent with in vitro data, BAdv-Ag85B-TLR-2 and BAdv-Ag85B vaccinated mice exhibited reduced lung CFUs of Mtb by 1.5 log and 1.7 log respectively whereas BCG vaccinated mice could reduce CFUs by 0.95 log as compared to unvaccinated mice. In addition, the BAdv vaccines also protected spleens better than BCG suggesting improved protection against disseminated tuberculosis. Since BAdv can be given through mucosal route, we propose that they offer a novel mean to enhance lung and systemic immunity against tuberculosis.

Tuberculosis remains a major threat as drug resistance continues to increase. Pulmonary tuberculosis in adults is responsible for 80% of clinical cases and nearly 100% of transmission of infection. Unfortunately, since we have no animal models of adult type pulmonary tuberculosis, the most important type of disease remains largely out of reach of modern science and many fundamental questions remain unanswered. This paper reviews research dating back to the 1950’s providing compelling evidence that cord factor (trehalose 6,6′ dimycolate [TDM]) is essential for understanding tuberculosis. However, the original papers by Bloch and Noll were too far ahead of their time to have immediate impact. We can now recognize that the physical and biologic properties of cord factor are unprecedented in science, especially its ability to switch between two sets of biologic activities with changes in conformation. While TDM remains on organisms, it protects them from killing within macrophages, reduces antibiotic effectiveness and inhibits the stimulation of protective immune responses. If it comes off organisms and associates with lipid, TDM becomes a driver of tissue damage and necrosis. Studies emanating from cord factor research have produced (1) a rationale for improving vaccines, (2) an approach to new drugs that overcome natural resistance to antibiotics, (3) models of caseating granulomas that reproduce multiple manifestations of human tuberculosis. (4) evidence that TDM is a key T cell antigen in destructive lesions of tuberculosis, and (5) a new understanding of the pathology and pathogenesis of postprimary tuberculosis that can guide more informative studies of long standing mysteries of tuberculosis.

The variable efficacy of Bacille Calmette Guerin (BCG) vaccination against tuberculosis has prompted efforts to improve the vaccine. In this study, we used autophagy to enhance vaccine efficacy against tuberculosis in a mouse model. We examined the effect of autophagy on the processing of the immunodominant mycobacterial antigen Ag85B by antigen presenting cells (APCs), macrophages and dendritic cells (DCs). We found that rapamycin-induced autophagy enhanced Ag85B presentation by APCs infected with wild-type Mycobacterium tuberculosis H37Rv, H37Rv-derived DeltafbpA attenuated candidate vaccine or BCG. Furthermore, rapamycin enhanced localization of mycobacteria with autophagosomes and lysosomes. Rapamycin-enhanced antigen presentation was attenuated when autophagy was suppressed by 3-methyladenine or by small interfering RNA against beclin-1. Notably, mice immunized with rapamycin-treated DCs infected with either DeltafbpA or BCG showed enhanced T helper type 1-mediated protection when challenged with virulent Mycobacterium tuberculosis. Finally, overexpression of Ag85B in BCG induced autophagy in APCs and enhanced immunogenicity in mice, suggesting that vaccine efficacy can be enhanced by augmenting autophagy-mediated antigen presentation.

Objective: Tuberculosis has a staggering influence on world health, resulting in nearly 2 million deaths per year. The influence of glucocorticoids during Mycobacterium tuberculosis infection has been under investigation for decades; however, the identity of mycobacterial factors and the mechanism by which glucocorticoids are tissue specifically regulated to influence immune function during acute granuloma formation are unknown. Methods: One factor implicated in initiating immunopathology during M. tuberculosis infection is trehalose-6,6′-dimycolate (TDM), a glycolipid component of the mycobacterial cell wall. Intravenous administration of TDM causes inflammatory responses in lungs of mice similar to M. tuberculosis infection and has been used as a successful model to examine proinflammatory regulation and early events involved in the manifestation of pathology. Results and Conclusion: IL-6, IL-1α and TNF-α mRNA and protein peaked during the initiation of granuloma formation. Pulmonary corticosterone levels were elevated when the proinflammatory response was greatest, dropping to half of that upon the establishment of granuloma pathology on day 7. It is hypothesized that once corticosterone reaches the site of inflammation, the enzymes 11β-hydroxysteroid dehydrogenases (11βHSDs) can influence bioavailability by interconverting corticosterone and the inert metabolite 11-dehydrocorticosterone. RT-PCR demonstrated that pulmonary 11βHSD type 1 mRNA decreased 4-fold and 11βHSD type 2 (11βHSD2) mRNA expression increased 2.5-fold on day 3 after injection, suggesting that corticosterone regulation in the lung, specifically the reduction of active corticosterone by 11βHSD2, may influence the progression of granuloma formation in response to the mycobacterial glycolipid.

Background Poloxamer 188 (P188), a nonionic block copolymer chemical surfactant known to have cytoprotective, rheologic, anti-inflammatory, and anti-thrombotic activity, has shown promise in the management of selected trauma patients. We studied human PMN oxidative burst and adhesion molecule expression when exposed to P188. Methods After RBC lysis of whole blood samples, white blood cell components were primed with phosphotidylcholine, primed and activated with fMLP, primed and activated with PMA, or left unstimulated. Each group was treated with vehicle or P188 (0.005–15 mg/ml concentrations). Flow cytometry quantified: (1) PMN superoxide anion production and (2) PMN marker expression of CD11b and L-selectin. Results Among non-PMA activated PMNs, P188 increased superoxide anion production. PMA-activated PMNs decreased superoxide anion production, proportional to P188 dose. Among fMLP-activated PMNs, the highest P188 dose increased the expression of CD11b. Among PMA-activated PMNs, decreased CD11b expression was seen for the mid-range doses. Conclusions PMNs altered their oxidative burst and marker expression after exposure to P188. When used at lower doses, P188 may increase the oxidative burst response and, when used at very high doses, increase CD11b expression. However, if PMNs are in a maximally activated state, a higher dose of P188 may decrease the oxidative burst response and decrease CD11b expression.

Trehalose 6,6'-dimycolate (TDM) is a glycolipid component of the mycobacterial cell wall that causes immune responses in mice similar to Mycobacterium tuberculosis (MTB) infection, including granuloma formation with production of proinflammatory cytokines. The precise roles of tumour necrosis factor (TNF)-alpha, complement C5 and interleukin (IL)-6 in the molecular events that lead to the initiation and maintenance of the granulomatous response to TDM have not been fully elucidated. Macrophage proinflammatory responses from wild-type and complement-deficient mice after infection with MTB were assessed, and compared to responses from organisms in which surface TDM had been removed. Removal of TDM abolished proinflammatory responses, markedly so in the complement-deficient macrophages. Mice deficient in TNF-alpha, C5a and IL-6, along with wild-type C57BL/6 controls, were intravenously injected with TDM in a water-in-oil emulsion, and analysed for histological response and cytokine production in lungs. Wild-type C57BL/6 mice formed granulomas with increased production of IL-1beta, IL-6, TNF-alpha, macrophage inflammatory protein-1alpha (MIP-1alpha), IL-12p40, interferon-gamma (IFN-gamma), and IL-10 protein and mRNA. TNF-alpha-deficient mice failed to produce a histological response to TDM, with no increases in cytokine production following TDM administration. While C5a-deficient mice exhibited inflammation, they did not form structured granulomas and initially had decreased production of proinflammatory mediators. IL-6-deficient mice initiated granuloma formation, but failed to maintain the granulomas through day 7 and demonstrated decreased early production of proinflammatory mediators in comparison to wild-type mice. These data suggest that TNF-alpha is critical for initiation of the granulomatous response, C5a is necessary for formation of cohesive granulomas, and IL-6 plays a key role in the granuloma maintenance response to mycobacterial TDM.