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1.
Am J Drug Alcohol Abuse ; 49(3): 321-332, 2023 05 04.
Article in English | MEDLINE | ID: mdl-36206520

ABSTRACT

Background: Although alcohol and nicotine are often used together, the biological consequences of these substances are not well understood. Identifying shared targets will inform cessation pharmacotherapies and provide a deeper understanding of how co-use of alcohol and nicotine impacts health, including biomarkers of stress and inflammation.Objective: We examined the effects of nicotine exposure and withdrawal on alcohol self-administration (SA), stress and inflammatory biomarkers, and a G-protein coupled receptor subunit (Gß) in brain areas associated with drug use.Methods: Male rats were trained to SA alcohol and then received a nicotine pump (n = 7-8 per group). We assessed alcohol intake for 12 days during nicotine exposure and then following pump removal to elicit withdrawal. After the behavioral studies, we assessed plasma leptin, corticosterone, and interleukin-1ß (IL-1ß), and Gß protein expression in the amygdala, nucleus accumbens (NAc), and prefrontal cortex (PFC).Results: Nicotine exposure or withdrawal did not alter alcohol intake (p > .05). Alcohol and nicotine withdrawal elevated corticosterone levels (p = .015) and decreased Gß levels in the PFC (p = .004). In the absence of nicotine, alcohol SA suppressed IL-1ß levels (p = .039). Chronic exposure to nicotine or withdrawal during alcohol SA did not alter leptin levels or Gß expression in the amygdala or NAc (p's > .05).Conclusions: The combination of alcohol SA and nicotine withdrawal produced a persistent increase in stress biomarkers and a suppression in Gß expression in the PFC, providing an important first step toward understanding the common biological mechanisms of alcohol/nicotine misuse.


Subject(s)
Nicotine , Substance Withdrawal Syndrome , Rats , Male , Animals , Nicotine/adverse effects , Leptin/metabolism , Leptin/pharmacology , Leptin/therapeutic use , Corticosterone/metabolism , Corticosterone/pharmacology , Corticosterone/therapeutic use , Rats, Wistar , Substance Withdrawal Syndrome/drug therapy , Prefrontal Cortex , Ethanol/adverse effects
2.
Med Chem Res ; 29(1): 126-135, 2020.
Article in English | MEDLINE | ID: mdl-32435125

ABSTRACT

Inflammasomes are multiprotein assemblies that produce robust inflammatory responses upon stimulation with pathogen- and/or danger-associated molecular patterns. Uncontrolled inflammasome activation has been linked to the pathophysiology of a wide array of disorders including life-threatening pathogenic infections, e.g., Francisella tularensis. There has been a great deal of interest in the development of small molecule inflammasome inhibitors. Using computational modeling based on chalcone derivatives, we have developed novel tertiary sulfonylurea compounds as inhibitors of the NLRP3 inflammasome. The polar enone functional alert of chalcone was replaced with a sulfonylurea scaffold while maintaining the relative positions of the two aromatic rings. These compounds were evaluated for their ability to inhibit NLRP3 and AIM2 inflammasome activation triggered by Francisella tularensis infection.

3.
Infect Immun ; 84(2): 580-9, 2016 02.
Article in English | MEDLINE | ID: mdl-26644385

ABSTRACT

Numerous pathogens, including Mycobacterium tuberculosis, can activate human γ9δ2 T cells to proliferate and express effector mechanisms. γ9δ2 T cells can directly inhibit the growth of intracellular mycobacteria and may also act as antigen-presenting cells (APC). Despite evidence for γδ T cells having the capacity to function as APC, the mechanisms involved and importance of these effects on overall tuberculosis (TB) immunity are unknown. We prepared M. tuberculosis-specific γ9δ2 T cell lines to study their direct protective effects and APC functions for M. tuberculosis-specific αß T cells. The direct inhibitory effects on intracellular mycobacteria were measured, and the enhancing effects on proliferative and effector responses of αß T cells assessed. Furthermore, the importance of cell-to-cell contact and soluble products for γ9δ2 T cell effector responses and APC functions were investigated. We demonstrate, in addition to direct inhibitory effects on intracellular mycobacteria, the following: (i) γ9δ2 T cells enhance the expansion of M. tuberculosis-specific αß T cells and increase the ability of αß T cells to inhibit intracellular mycobacteria; (ii) although soluble mediators are critical for the direct inhibitory effects of γ9δ2 T cells, their APC functions do not require soluble mediators; (iii) the APC functions of γ9δ2 T cells involve cell-to-cell contact that is dependent on CD40-CD40 ligand (CD40L) interactions; and (iv) fully activated CD4(+) αß T cells and γ9δ2 T cells provide similar immune enhancing/APC functions for M. tuberculosis-specific T cells. These effector and helper effects of γ9δ2 T cells further indicate that these T cells should be considered important new targets for new TB vaccines.


Subject(s)
Antigen Presentation , CD40 Ligand/immunology , Mycobacterium tuberculosis/immunology , T-Lymphocyte Subsets/immunology , Tuberculosis/immunology , CD4-Positive T-Lymphocytes , CD40 Antigens/immunology , CD40 Antigens/metabolism , CD40 Ligand/metabolism , Cell Line , Dendritic Cells/immunology , Dendritic Cells/microbiology , Humans , Immunologic Memory , Leukocytes, Mononuclear/immunology , Lymphocyte Activation , Mycobacterium tuberculosis/growth & development
4.
Infect Immun ; 84(9): 2449-62, 2016 09.
Article in English | MEDLINE | ID: mdl-27297390

ABSTRACT

γ9δ2 T cells provide a natural bridge between innate and adaptive immunity, rapidly and potently respond to pathogen infection in mucosal tissues, and are prominently induced by both tuberculosis (TB) infection and bacillus Calmette Guérin (BCG) vaccination. Mycobacterium-expanded γ9δ2 T cells represent only a subset of the phosphoantigen {isopentenyl pyrophosphate [IPP] and (E)-4-hydroxy-3-methyl-but-2-enylpyrophosphate [HMBPP]}-responsive γ9δ2 T cells, expressing an oligoclonal set of T cell receptor (TCR) sequences which more efficiently recognize and inhibit intracellular Mycobacterium tuberculosis infection. Based on this premise, we have been searching for M. tuberculosis antigens specifically capable of inducing a unique subset of mycobacterium-protective γ9δ2 T cells. Our screening strategy includes the identification of M. tuberculosis fractions that expand γ9δ2 T cells with biological functions capable of inhibiting intracellular mycobacterial replication. Chemical treatments of M. tuberculosis whole-cell lysates (MtbWL) ruled out protein, nucleic acid, and nonpolar lipids as the M. tuberculosis antigens inducing protective γ9δ2 T cells. Mild acid hydrolysis, which transforms complex carbohydrate to monomeric residues, abrogated the specific activity of M. tuberculosis whole-cell lysates, suggesting that a polysaccharide was required for biological activity. Extraction of MtbWL with chloroform-methanol-water (10:10:3) resulted in a polar lipid fraction with highly enriched specific activity; this activity was further enriched by silica gel chromatography. A combination of mass spectrometry and nuclear magnetic resonance analysis of bioactive fractions indicated that 6-O-methylglucose-containing lipopolysaccharides (mGLP) are predominant components present in this active fraction. These results have important implications for the development of new immunotherapeutic approaches for prevention and treatment of TB.


Subject(s)
Glycolipids/immunology , Lymphocyte Activation/immunology , Mycobacterium tuberculosis/immunology , Receptors, Antigen, T-Cell, gamma-delta/immunology , T-Lymphocyte Subsets/immunology , Tuberculosis/immunology , Adaptive Immunity/immunology , Animals , Antigens, Bacterial/immunology , Hemiterpenes/immunology , Methylglucosides/immunology , Organophosphorus Compounds/immunology , Polysaccharides/immunology , T-Lymphocyte Subsets/microbiology , Tuberculosis/microbiology
5.
PLoS Pathog ; 9(1): e1003119, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23326234

ABSTRACT

Human γ(9)δ(2) T cells potently inhibit pathogenic microbes, including intracellular mycobacteria, but the key inhibitory mechanism(s) involved have not been identified. We report a novel mechanism involving the inhibition of intracellular mycobacteria by soluble granzyme A. γ(9)δ(2) T cells produced soluble factors that could pass through 0.45 µm membranes and inhibit intracellular mycobacteria in human monocytes cultured below transwell inserts. Neutralization of TNF-α in co-cultures of infected monocytes and γ(9)δ(2) T cells prevented inhibition, suggesting that TNF-α was the critical inhibitory factor produced by γ(9)δ(2) T cells. However, only siRNA- mediated knockdown of TNF-α in infected monocytes, but not in γ(9)δ(2) T cells, prevented mycobacterial growth inhibition. Investigations of other soluble factors produced by γ(9)δ(2) T cells identified a highly significant correlation between the levels of granzyme A produced and intracellular mycobacterial growth inhibition. Furthermore, purified granzyme A alone induced inhibition of intracellular mycobacteria, while knockdown of granzyme A in γ(9)δ(2) T cell clones blocked their inhibitory effects. The inhibitory mechanism was independent of autophagy, apoptosis, nitric oxide production, type I interferons, Fas/FasL and perforin. These results demonstrate a novel microbial defense mechanism involving granzyme A-mediated triggering of TNF-α production by monocytes leading to intracellular mycobacterial growth suppression. This pathway may provide a protective mechanism relevant for the development of new vaccines and/or immunotherapies for macrophage-resident chronic microbial infections.


Subject(s)
Granzymes/metabolism , Macrophages/enzymology , Monocytes/enzymology , Mycobacterium/physiology , T-Lymphocyte Subsets/enzymology , Cells, Cultured , Gene Expression Regulation, Bacterial , Gene Knockdown Techniques , Granzymes/genetics , Granzymes/pharmacology , Host-Pathogen Interactions , Humans , Macrophages/immunology , Macrophages/microbiology , Monocytes/immunology , Monocytes/microbiology , Mycobacterium/drug effects , Neutralization Tests , RNA, Small Interfering/genetics , Receptors, Antigen, T-Cell, gamma-delta/immunology , Receptors, Antigen, T-Cell, gamma-delta/metabolism , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/microbiology , Tumor Necrosis Factor-alpha/metabolism
6.
Eur J Immunol ; 43(5): 1162-72, 2013 May.
Article in English | MEDLINE | ID: mdl-23386199

ABSTRACT

It is generally assumed that the MHC class I antigen (Ag)-processing (CAP) machinery - which supplies peptides for presentation by class I molecules - plays no role in class II-restricted presentation of cytoplasmic Ags. In striking contrast to this assumption, we previously reported that proteasome inhibition, TAP deficiency or ERAAP deficiency led to dramatically altered T helper (Th)-cell responses to allograft (HY) and microbial (Listeria monocytogenes) Ags. Herein, we tested whether altered Ag processing and presentation, altered CD4(+) T-cell repertoire, or both underlay the above finding. We found that TAP deficiency and ERAAP deficiency dramatically altered the quality of class II-associated self peptides suggesting that the CAP machinery impacts class II-restricted Ag processing and presentation. Consistent with altered self peptidomes, the CD4(+) T-cell receptor repertoire of mice deficient in the CAP machinery substantially differed from that of WT animals resulting in altered CD4(+) T-cell Ag recognition patterns. These data suggest that TAP and ERAAP sculpt the class II-restricted peptidome, impacting the CD4(+) T-cell repertoire, and ultimately altering Th-cell responses. Together with our previous findings, these data suggest multiple CAP machinery components sequester or degrade MHC class II-restricted epitopes that would otherwise be capable of eliciting functional Th-cell responses.


Subject(s)
Antigen Presentation , Antigen-Presenting Cells/immunology , Histocompatibility Antigens Class II/immunology , Histocompatibility Antigens Class I/immunology , T-Lymphocytes, Helper-Inducer/immunology , Amino Acid Sequence , Animals , Antigen-Presenting Cells/cytology , Antigen-Presenting Cells/metabolism , Antigens, Ly/genetics , Antigens, Ly/immunology , Epitopes/chemistry , Epitopes/immunology , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class II/genetics , Leucyl Aminopeptidase/deficiency , Leucyl Aminopeptidase/genetics , Leucyl Aminopeptidase/immunology , Membrane Proteins/deficiency , Membrane Proteins/genetics , Membrane Proteins/immunology , Mice , Mice, Knockout , Molecular Sequence Data , Peptide Fragments/chemistry , Peptide Fragments/immunology , Proteomics , Sequence Analysis, Protein , T-Lymphocytes, Helper-Inducer/cytology , T-Lymphocytes, Helper-Inducer/metabolism , Tandem Mass Spectrometry
7.
Pathogens ; 13(10)2024 Oct 19.
Article in English | MEDLINE | ID: mdl-39452784

ABSTRACT

In response to the SARS-CoV-2 pandemic, the United States declared a state of emergency and implemented large-scale shutdowns and public health initiatives to prevent overwhelming public resources. The success of these prevention methods remains unresolved as restrictions and implementation varied from national, state, and local levels. Despite national and local regulations, individual adherence to preventative guidelines presented an additional layer of variability. Cases of COVID-19 continued to rise and fall over a two-year period on a national level, despite masking recommendations, ease of testing, and availability of vaccines. The Ysleta del Sur Pueblo is a Native American tribal community and sovereign nation located in El Paso, Texas. Speaking Rock Entertainment Center is a major business operated by the tribe, employing many tribal and non-tribal members from the El Paso area. Following nationwide re-openings of non-essential businesses, Speaking Rock implemented an infection control program with strict adherence to recommendations provided by the Center for Disease Control and Prevention (CDC) and additional disease control. This response would result in a fully vaccinated workforce within the wider community of El Paso, where the vaccination rate was less than 80%. Herein, we examine the efficacy of these measures and report on the success of the program resulting in zero hospitalizations or deaths compared with rates of 1 in 250 and 1 in 40, respectively, in the surrounding community.

8.
ArXiv ; 2024 Feb 28.
Article in English | MEDLINE | ID: mdl-37961741

ABSTRACT

Enumerated threat agent lists have long driven biodefense priorities. The global SARS-CoV-2 pandemic demonstrated the limitations of searching for known threat agents as compared to a more agnostic approach. Recent technological advances are enabling agent-agnostic biodefense, especially through the integration of multi-modal observations of host-pathogen interactions directed by a human immunological model. Although well-developed technical assays exist for many aspects of human-pathogen interaction, the analytic methods and pipelines to combine and holistically interpret the results of such assays are immature and require further investments to exploit new technologies. In this manuscript, we discuss potential immunologically based bioagent-agnostic approaches and the computational tool gaps the community should prioritize filling.

9.
J Immunol ; 187(12): 6335-45, 2011 Dec 15.
Article in English | MEDLINE | ID: mdl-22084435

ABSTRACT

Semi-invariant NKT cells are thymus-derived innate-like lymphocytes that modulate microbial and tumor immunity as well as autoimmune diseases. These immunoregulatory properties of NKT cells are acquired during their development. Much has been learned regarding the molecular and cellular cues that promote NKT cell development, yet how these cells are maintained in the thymus and the periphery and how they acquire functional competence are incompletely understood. We found that IL-15 induced several Bcl-2 family survival factors in thymic and splenic NKT cells in vitro. Yet, IL-15-mediated thymic and peripheral NKT cell survival critically depended on Bcl-x(L) expression. Additionally, IL-15 regulated thymic developmental stage 2 to stage 3 lineage progression and terminal NKT cell differentiation. Global gene expression analyses and validation revealed that IL-15 regulated Tbx21 (T-bet) expression in thymic NKT cells. The loss of IL-15 also resulted in poor expression of key effector molecules such as IFN-γ, granzyme A and C, as well as several NK cell receptors, which are also regulated by T-bet in NKT cells. Taken together, our findings reveal a critical role for IL-15 in NKT cell survival, which is mediated by Bcl-x(L), and effector differentiation, which is consistent with a role of T-bet in regulating terminal maturation.


Subject(s)
Cell Differentiation/immunology , Homeostasis/immunology , Interleukin-15/physiology , Natural Killer T-Cells/immunology , Natural Killer T-Cells/metabolism , Animals , Cell Differentiation/genetics , Cell Lineage/genetics , Cell Lineage/immunology , Cell Survival/genetics , Cell Survival/immunology , Homeostasis/genetics , Interleukin-15/deficiency , Interleukin-15/genetics , Liver/cytology , Liver/immunology , Liver/metabolism , Lymphocyte Count , Mice , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Natural Killer T-Cells/cytology , Spleen/cytology , Spleen/immunology , Spleen/metabolism , Thymus Gland/cytology , Thymus Gland/immunology , Thymus Gland/metabolism , bcl-X Protein/biosynthesis , bcl-X Protein/genetics , bcl-X Protein/metabolism
10.
Alcohol ; 112: 9-16, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37454744

ABSTRACT

BACKGROUND: Allostatic load (AL) is associated with a heightened predisposition to disease due to prolonged activation of biological stress-response systems. Alcohol use disorder (AUD) is known to activate these systems. The primary aim of the current study was to examine the relationship between AL and AUD. METHODS: Participants were males (100%) with DSM-IV Alcohol Dependence (n = 48) and healthy participants with no history of substance use disorder (n = 17). Participants with AUD were 4-6 weeks abstinent. The AL index used cortisol, interleukin-6 (IL-6), fibrinogen, tumor necrosis factor-alpha (TNFα), C-reactive protein (CRP), glucose, insulin, leptin, pulse, systolic blood pressure readings, diastolic blood pressure readings, and body mass index (BMI). Physiological dysregulation for each biological measure was determined based on values within the 25th or 75th percentiles; AL was calculated as the total number of physiologically dysregulated biological measures. RESULTS: No differences in mean AL scores between the cases and controls [t(63) = .48, p = .633] were observed. Among cases, AL was not associated with lifetime drinks per drinking day (F(2,42) = .42, p = .662), lifetime total drinks (F(2,42) = 0.48, p = .620), total drinks 6 months prior to participating in the study (F(2,43) = 0.58, p = .563), or drinks per drinking day at 3-month follow-up (F(2,35) = 1.93, p = .161). AL was negatively associated with drinks per drinking day 6 months prior to study participation (F(2,42) = 3.71, p = .033). CONCLUSIONS: The hypotheses were not supported. Given that alcohol is likely to lead to physiological dysregulation, the apparent absence of a relationship between biomarkers of cumulative stress as indicated by AL and drinking status was both unanticipated and remarkable. Based on the results, AL in the context of drinking status or drinking among males with AUD may not be applicable.

11.
J Infect Dis ; 204(6): 845-53, 2011 Sep 15.
Article in English | MEDLINE | ID: mdl-21846636

ABSTRACT

BACKGROUND: Two doses of either trivalent live attenuated or inactivated influenza vaccines (LAIV and TIV, respectively) are approved for young children (≥ 24 months old for LAIV and ≥ 6 months old for TIV) and induce protective antibody responses. However, whether combinations of LAIV and TIV are safe and equally immunogenic is unknown. Furthermore, LAIV is more protective than TIV in children for unclear reasons. METHODS: Children 6-35 months old were administered, 1 month apart, 2 doses of either TIV or LAIV, or combinations of LAIV and TIV in both prime/boost sequences. Influenza-specific antibodies were measured by hemagglutination inhibition (HAI), and T cells were studied in flow cytometric and functional assays. Highly conserved M1, M2, and NP peptides predicted to be presented by common HLA class I and II were used to stimulate interferon-γ enzyme-linked immunospot responses. RESULTS: All LAIV and/or TIV combinations were well tolerated and induced similar HAI responses. In contrast, only regimens containing LAIV induced influenza-specific CD4(+), CD8(+), and γδ T cells, including T cells specific for highly conserved influenza peptides. CONCLUSIONS: Prime/boost combinations of LAIV and TIV in young children were safe and induced similar protective antibodies. Only LAIV induced CD4(+), CD8(+), and γδ T cells relevant for broadly protective heterosubtypic immunity. CLINICAL TRIALS REGISTRATION: NCT00231907.


Subject(s)
Antibodies, Viral/blood , Influenza Vaccines/immunology , Influenza, Human/prevention & control , T-Lymphocytes/immunology , Child, Preschool , Enzyme-Linked Immunospot Assay , Female , Flow Cytometry , Hemagglutination Inhibition Tests , Humans , Immunization, Secondary/adverse effects , Immunization, Secondary/methods , Infant , Influenza Vaccines/administration & dosage , Influenza Vaccines/adverse effects , Male , Vaccination/adverse effects , Vaccination/methods , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/adverse effects , Vaccines, Attenuated/immunology , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/adverse effects , Vaccines, Inactivated/immunology
12.
Methods Mol Biol ; 2321: 75-100, 2021.
Article in English | MEDLINE | ID: mdl-34048009

ABSTRACT

Sepsis results from the dysregulated immune response to infection. While the stimulator and progression of the septic response is poorly understood, the systemic production of a storm of cytokines is common in all etiologies of sepsis. While the complexity of this uncontrolled cascade is difficult to replicate using single molecule agonist, for example, lipopolysaccharide (LPS), several whole organism models can stimulate this cytokine storm. Herein, we detail protocols developed to trigger and analyze the systemic septic response in mouse models using the bacterium Francisella tularensis.


Subject(s)
Francisella tularensis/immunology , Sepsis/immunology , Sepsis/microbiology , Tularemia/immunology , Tularemia/microbiology , Animals , Cytokines/immunology , Disease Models, Animal , Disease Progression , Lipopolysaccharides/immunology , Mice , Mice, Inbred C57BL
13.
J Immunol ; 181(7): 4471-84, 2008 Oct 01.
Article in English | MEDLINE | ID: mdl-18802050

ABSTRACT

Mycobacterium tuberculosis and Mycobacterium bovis bacillus Calmette-Guérin (BCG) induce potent expansions of human memory Vgamma(9)(+)Vdelta(2)(+) T cells capable of IFN-gamma production, cytolytic activity, and mycobacterial growth inhibition. Certain phosphoantigens expressed by mycobacteria can stimulate gamma(9)delta(2) T cell expansions, suggesting that purified or synthetic forms of these phosphoantigens may be useful alone or as components of new vaccines or immunotherapeutics. However, we show that while mycobacteria-activated gamma(9)delta(2) T cells potently inhibit intracellular mycobacterial growth, phosphoantigen-activated gamma(9)delta(2) T cells fail to inhibit mycobacteria, although both develop similar effector cytokine and cytolytic functional capacities. gamma(9)delta(2) T cells receiving TLR-mediated costimulation during phosphoantigen activation also failed to inhibit mycobacterial growth. We hypothesized that mycobacteria express Ags, other than the previously identified phosphoantigens, that induce protective subsets of gamma(9)delta(2) T cells. Testing this hypothesis, we compared the TCR sequence diversity of gamma(9)delta(2) T cells expanded with BCG-infected vs phosphoantigen-treated dendritic cells. BCG-stimulated gamma(9)delta(2) T cells displayed a more restricted TCR diversity than phosphoantigen-activated gamma(9)delta(2) T cells. In addition, only a subset of phosphoantigen-activated gamma(9)delta(2) T cells functionally responded to mycobacteria-infected dendritic cells. Furthermore, differential inhibitory functions of BCG- and phosphoantigen-activated gamma(9)delta(2) T cells were confirmed at the clonal level and were not due to differences in TCR avidity. Our results demonstrate that BCG infection can activate and expand protective subsets of phosphoantigen-responsive gamma(9)delta(2) T cells, and provide the first indication that gamma(9)delta(2) T cells can develop pathogen specificity similar to alphabeta T cells. Specific targeting of protective gamma(9)delta(2) T cell subsets will be important for future tuberculosis vaccines.


Subject(s)
Antigens, Bacterial/immunology , Hemiterpenes/immunology , Lymphocyte Activation/immunology , Mycobacterium bovis/immunology , Organophosphorus Compounds/immunology , Receptors, Antigen, T-Cell, gamma-delta/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/microbiology , Tuberculosis, Pulmonary/immunology , Amino Acid Sequence , Cell Line , Clone Cells , Humans , Immunity, Innate , Molecular Sequence Data , Mycobacterium bovis/growth & development , Receptors, Antigen, T-Cell, gamma-delta/biosynthesis , Receptors, Antigen, T-Cell, gamma-delta/genetics , T-Lymphocyte Subsets/metabolism , Tuberculosis, Pulmonary/microbiology
14.
Curr Opin Organ Transplant ; 15(4): 512-25, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20616723

ABSTRACT

PURPOSE OF REVIEW: There is ample evidence indicating a pathologic role for minor histocompatibility antigens in inciting graft-versus-host disease in major histocompatibility complex (MHC)-matched bone marrow transplantation and rejection of solid organ allografts. Here we review the current knowledge of the genetic and biochemical bases for the cause of minor histoincompatibility and the structural basis for the recognition of the resulting alloantigens by the T-cell receptor. RECENT FINDINGS: Recent evidence indicates that we as independently conceived individuals are genetically unique, thus, offering a mechanism for minor histoincompatibility between MHC-identical donor-recipient pairs. Furthermore, advances in delineating the mechanisms underlying antigen cross-presentation by MHC class I molecules and a critical role for autophagy in presenting cytoplasmic antigens by MHC class II molecules have been made. These new insights coupled with the X-ray crystallographic solution of several peptide/MHC-T-cell receptor structures have revealed mechanisms of histoincompatibility. SUMMARY: On the basis of these new insights, ways to test for allograft compatibility and concoction of immunotherapies are discussed.


Subject(s)
Graft Rejection/immunology , Graft Survival , Graft vs Host Disease/immunology , Isoantigens/immunology , Minor Histocompatibility Antigens/immunology , Receptors, Antigen, T-Cell/immunology , T-Lymphocytes/immunology , Transplantation Tolerance , Animals , Graft Rejection/prevention & control , Graft vs Host Disease/prevention & control , Humans , Immunosuppression Therapy/methods , Inflammation/immunology , Isoantigens/chemistry , Isoantigens/genetics , Ligands , Minor Histocompatibility Antigens/chemistry , Minor Histocompatibility Antigens/genetics , Models, Molecular , Protein Conformation , Structure-Activity Relationship , Transplantation, Homologous
15.
Int J Nanomedicine ; 15: 5097-5111, 2020.
Article in English | MEDLINE | ID: mdl-32764939

ABSTRACT

INTRODUCTION: In this in-vitro study, we designed a 3D printed composite of zinc oxide (ZnO) nanoparticles (NPs) with photocatalytic activities encapsulated within hydrogel (alginate) constructs, for antibacterial purposes applicable towards wound healing. We primarily sought to confirm the mechanical properties and cell compatibility of these ZnO NP infused scaffolds. METHODS: The antibacterial property of the ZnO NPs was confirmed by hydroxyl radical generation using ultraviolet (U.V.) photocatalysis. Titanium dioxide (TiO2), a well-known antibacterial compound, was used as a positive control (1% w/v) for the ZnO NP-based alginate constructs and their antibacterial efficacies compared. Among the ZnO group, 3D printed gels containing 0.5% and 1% w/v of ZnO were analyzed and compared with manually casted samples via SEM, swelling evaluation, and rheological analysis. Envisioning an in-vivo application for the 3D printed ZnO NP-based alginates, we studied their antibacterial properties by bacterial broth testing, cytocompatibility via live/dead assay, and moisture retention capabilities utilizing a humidity sensor. RESULTS: 3D printed constructs revealed significantly greater pore sizes and enhanced structural stability compared to manually casted samples. For all samples, the addition of ZnO or TiO2 resulted in significantly stiffer gels in comparison with the alginate control. Bacterial resistance testing on Staphylococcus epidermidis indicated the addition of ZnO NPs to the gels decreased bacterial growth when compared to the alginate only gels. Cell viability of STO-fibroblasts was not adversely affected by the addition of ZnO NPs to the alginate gels. Furthermore, the addition of increasing doses of ZnO NPs to the alginate demonstrated increased humidity retention in gels. DISCUSSION: The customization of 3D printed alginates containing antibacterial ZnO NPs leads to an alternative that allows accessible mobility of molecular exchange required for improving chronic wound healing. This scaffold can provide a cost-effective and durable antibacterial treatment option.


Subject(s)
Alginates/chemistry , Alginates/pharmacology , Hydrogels/chemistry , Nanoparticles/chemistry , Wound Healing/drug effects , Zinc Oxide/chemistry , Cell Survival/drug effects , Fibroblasts/cytology
16.
Neuropsychopharmacology ; 44(6): 1141-1151, 2019 05.
Article in English | MEDLINE | ID: mdl-30647447

ABSTRACT

This study examined whether the strong reinforcing effects of nicotine and changes in insulin biomarkers observed in diabetic rats are modulated via insulin. A model of diabetes was employed involving administration of streptozotocin (STZ), which produces hypoinsulinemia in rats. The present study included vehicle- or STZ-treated rats that received sham surgery or insulin pellets. Two weeks later, the rats were given extended access to intravenous self-administration (IVSA) of saline or nicotine. Concomitant changes in food intake, water responses, and body weight were assessed during 12 days of IVSA. After the last session, plasma levels of insulin, leptin, amylin, and glucagon-like peptide-1 (GLP-1) were assessed using Luminex® technology. In a separate cohort, phosphorylated insulin receptor substrate-2 (pIRS-2) and insulin growth factor-1 receptor ß (IGF-1Rß) were assessed in the nucleus accumbens (NAc) and ventral tegmental area (VTA) of vehicle- or STZ-treated rats that received sham surgery or an insulin pellet. STZ-treated rats displayed an increase in glucose levels, a decrease in body weight, and an increase in nicotine, food, and water intake relative to controls. STZ-treated rats also displayed a decrease in plasma insulin and leptin levels and an increase in amylin and GLP-1 levels relative to controls. Importantly, all of the STZ-induced changes in behavior and insulin biomarkers were prevented by insulin supplementation. STZ-treated rats also displayed a decrease in pIRS-2 and IGF-1Rß in the NAc (but not VTA), an effect that was also prevented by insulin. These data suggest that insulin systems in the NAc modulate the strong reinforcing effects of nicotine in male diabetic rats.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Glucagon-Like Peptide 1/blood , Insulin Receptor Substrate Proteins/metabolism , Insulin/blood , Islet Amyloid Polypeptide/blood , Leptin/blood , Nicotine/pharmacology , Nicotinic Agonists/pharmacology , Nucleus Accumbens/metabolism , Receptor, IGF Type 1/metabolism , Reinforcement, Psychology , Ventral Tegmental Area/metabolism , Animals , Behavior, Animal/drug effects , Biomarkers/blood , Body Weight/drug effects , Drinking Behavior/drug effects , Feeding Behavior/drug effects , Male , Nicotine/administration & dosage , Nicotinic Agonists/administration & dosage , Rats , Rats, Wistar , Self Administration , Water
18.
Biomed Res Int ; 2018: 3412732, 2018.
Article in English | MEDLINE | ID: mdl-30046592

ABSTRACT

Infection with Francisella tularensis, the causative agent of the human disease tularemia, results in the overproduction of inflammatory cytokines, termed the cytokine storm. Excess metabolic byproducts of obesity accumulate in obese individuals and activate the same inflammatory signaling pathways as F. tularensis infection. In addition, elevated levels of leptin in obese individuals also increase inflammation. Since leptin is produced by adipocytes, we hypothesized that increased fat of obese females may make them more susceptible to F. tularensis infection compared with lean individuals. Lean and obese female mice were infected with F. tularensis and the immunopathology and susceptibility monitored. Plasma and tissue cytokines were analyzed by multiplex ELISA and real-time RT-PCR, respectively. Obese mice were more sensitive to infection, developing a more intense cytokine storm, which was associated with increased death of obese mice compared with lean mice. This enhanced inflammatory response correlated with in vitro bacteria-infected macrophage cultures where addition of leptin led to increased production of inflammatory cytokines. We conclude that increased basal leptin expression in obese individuals causes a persistent low-level inflammatory response making them more susceptible to F. tularensis infection and heightening the generation of the immunopathological cytokine storm.


Subject(s)
Cytokines/metabolism , Francisella tularensis/pathogenicity , Obesity/complications , Tularemia/immunology , Animals , Female , Humans , Leptin/metabolism , Male , Mice , Mice, Inbred C57BL , Tularemia/mortality
19.
Article in English | MEDLINE | ID: mdl-16511324

ABSTRACT

The extracellular fibrinogen-binding protein (Efb) of Staphylococcus aureus is a multifunctional virulence factor capable of potent inhibition of complement component-3 (C3) activity in addition to its previously described fibrinogen-binding properties. A truncated recombinant form of Efb (Efb-C) that binds C3 has been overexpressed and purified and has been crystallized using the hanging-drop vapor-diffusion technique. Crystals of native Efb-C grew in the tetragonal space group P4(3) (unit-cell parameters a = b = 59.53, c = 46.63 A) with two molecules in the asymmetric unit and diffracted well beyond 1.25 A limiting Bragg spacing. To facilitate de novo phasing of the Efb-C crystals, two independent site-directed mutants were engineered in which either residue Ile112 or Val140 was replaced with methionine and crystals isomorphous to those of native Efb-C were reproduced using a seleno-L-methionine-labeled form of each mutant protein. Multiwavelength anomalous diffraction (MAD) data were collected on both mutants and analyzed for their phasing power toward solution and refinement of a high-resolution Efb-C crystal structure.


Subject(s)
Bacterial Proteins/chemistry , Complement C3/antagonists & inhibitors , Staphylococcus aureus/chemistry , Bacterial Proteins/genetics , Complement C3/metabolism , Crystallization/methods , Crystallography, X-Ray , Mutagenesis, Site-Directed , Protein Structure, Tertiary/genetics
20.
Proteomes ; 4(4)2016.
Article in English | MEDLINE | ID: mdl-27882306

ABSTRACT

Medical diagnostics and treatment has advanced from a one size fits all science to treatment of the patient as a unique individual. Currently, this is limited solely to genetic analysis. However, epigenetic, transcriptional, proteomic, posttranslational modifications, metabolic, and environmental factors influence a patient's response to disease and treatment. As more analytical and diagnostic techniques are incorporated into medical practice, the personalized medicine initiative transitions to precision medicine giving a holistic view of the patient's condition. The high accuracy and sensitivity of mass spectrometric analysis of proteomes is well suited for the incorporation of proteomics into precision medicine. This review begins with an overview of the advance to precision medicine and the current state of the art in technology and instrumentation for mass spectrometry analysis. Thereafter, it focuses on the benefits and potential uses for personalized proteomic analysis in the diagnostic and treatment of individual patients. In conclusion, it calls for a synthesis between basic science and clinical researchers with practicing clinicians to design proteomic studies to generate meaningful and applicable translational medicine. As clinical proteomics is just beginning to come out of its infancy, this overview is provided for the new initiate.

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