Isolation of Tonsillar Mononuclear Cells to Study Ex Vivo Innate Immune Responses in a Human Mucosal Lymphoid Tissue

AbstractThe CXCR3 chemokine CXCL10 or IFN-γ inducible protein 10 (IP-10) has been identified as an important biomarker of cerebral malaria (CM) mortality in children. Studies in mouse malaria infection models have shown that CXCL10 blockade alleviates brain intravascular inflammation and protects infected mice from CM. Despite the key role that CXCL10 plays in the development of CM, the leucocytic sources of CXCL10 in response to human malaria are not known. Here we investigated CXCL10 responses to Plasmodium falciparum in peripheral blood mononuclear cells (PBMCs). We found that PBMCs from malaria-unexposed donors produce CXCL10 in response to P. falciparum and that this response is IFN-γ-dependent. Moreover, CD14+ monocytes were identified as the main leucocytic sources of CXCL10 in peripheral blood, suggesting an important role for innate immune responses in the activation of this pathway involved in the development of symptomatic malaria.

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Environment impacts innate immune ontogeny

Innate Immunity ◽

10.1177/1753425916671018 ◽

2016 ◽

Vol 23 (1) ◽

pp. 3-10 ◽

Cited By ~ 3

Author(s):

Mathieu Garand ◽

Bing Cai ◽

Tobias R Kollmann

Keyword(s):

Immune Responses ◽

Immune Modulation ◽

Mononuclear Cells ◽

Innate Immune ◽

Racial Groups ◽

Innate Immune Responses ◽

Susceptibility To Infection ◽

Cytokine Responses ◽

Underlying Mechanisms ◽

The Relationship

Susceptibility to infection and response to vaccination differ between populations and as a function of age. The underlying mechanisms for this age- and population-dependent variation are not known. Specifically, it is unclear if these variations are due to differences in genetically encoded host programs or driven by environmental influences or a combination of both. To address the relationship between gene and environment regarding immune ontogeny, we determined the innate cytokine responses following PRR stimulation of blood mononuclear cells at birth, 1, and 2 yr of age in infants from Caucasian vs . Asian parents and were raised in the same city. At birth, we found that innate cytokine responses were significantly elevated in Asian compared with Caucasian infants. However, these differences waned and responses became more similar over the course of 1–2 yr of living in a similar environment. Our observations that innate response differences present at birth subsequently equalized rather than diverged suggest a key role for environmental effects common to both racial groups in shaping the innate immune responses early in life. Delineating the underlying environmental factors that modulate innate immune responses early in life could provide avenues for targeted beneficial immune modulation.

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Early Clearance of Mycobacterium tuberculosis Is Associated With Increased Innate Immune Responses

The Journal of Infectious Diseases ◽

10.1093/infdis/jiz147 ◽

2019 ◽

Cited By ~ 12

Author(s):

Ayesha J Verrall ◽

Marion Schneider ◽

Bachti Alisjahbana ◽

Lika Apriani ◽

Arjan van Laarhoven ◽

...

Keyword(s):

Flow Cytometry ◽

Mycobacterium Tuberculosis ◽

Immune Responses ◽

Cellular Response ◽

Ex Vivo ◽

Interferon Γ ◽

Innate Immune ◽

Innate Immune Responses ◽

Cytokine Responses ◽

Protection Against Infection

AbstractBackgroundA proportion of tuberculosis (TB) case contacts do not become infected, even when heavily exposed. We studied the innate immune responses of TB case contacts to understand their role in protection against infection with Mycobacterium tuberculosis, termed “early clearance.”MethodsIndonesian household contacts of TB cases were tested for interferon-γ release assay (IGRA) conversion between baseline and 14 weeks post recruitment. Blood cell populations and ex vivo innate whole blood cytokine responses were measured at baseline and, in a subgroup, flow cytometry was performed at weeks 2 and 14. Immunological characteristics were measured for early clearers, defined as a persistently negative IGRA at 3 months, and converters, whose IGRA converted from negative to positive.ResultsAmong 1347 case contacts, 317 were early clearers and 116 were converters. Flow cytometry showed a resolving innate cellular response from 2 to 14 weeks in persistently IGRA-negative contacts but not converters. There were no differences in cytokine responses to mycobacterial stimuli, but compared to converters, persistently IGRA-negative contacts produced more proinflammatory cytokines following heterologous stimulation with Escherichia coli and Streptococcus pneumoniae.ConclusionsEarly clearance of M. tuberculosis is associated with enhanced heterologous innate immune responses similar to those activated during induction of trained immunity.

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Technical note: Determination of preanalysis storage temperature and time allowances for ex vivo innate immune responses

Journal of Dairy Science ◽

10.3168/jds.2012-5750 ◽

2013 ◽

Vol 96 (1) ◽

pp. 384-389 ◽

Cited By ~ 7

Author(s):

M.D. Sellers ◽

L.E. Hulbert ◽

M.A. Ballou

Keyword(s):

Immune Responses ◽

Storage Temperature ◽

Ex Vivo ◽

Technical Note ◽

Innate Immune ◽

Innate Immune Responses

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Tropism, replication competence, and innate immune responses of influenza virus: an analysis of human airway organoids and ex-vivo bronchus cultures

The Lancet Respiratory Medicine ◽

10.1016/s2213-2600(18)30236-4 ◽

2018 ◽

Vol 6 (11) ◽

pp. 846-854 ◽

Cited By ~ 28

Author(s):

Kenrie P Y Hui ◽

Rachel H H Ching ◽

Stan K H Chan ◽

John M Nicholls ◽

Norman Sachs ◽

...

Keyword(s):

Influenza Virus ◽

Immune Responses ◽

Ex Vivo ◽

Innate Immune ◽

Innate Immune Responses ◽

Human Airway

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Innate immune responses after stimulation with Toll-like receptor agonists in ex vivo microglial cultures and an in vivo model using mice with reduced microglia

Journal of Neuroinflammation ◽

10.1186/s12974-021-02240-w ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

James A. Carroll ◽

Brent Race ◽

Katie Williams ◽

James F. Striebel ◽

Bruce Chesebro

Keyword(s):

Gene Expression ◽

Immune Responses ◽

Ex Vivo ◽

Innate Immune ◽

Cpg Odn ◽

Innate Immune Responses ◽

Tlr Signaling ◽

Tlr Agonists ◽

Tlr7 Agonist

Abstract Background Past experiments studying innate immunity in the central nervous system (CNS) utilized microglia obtained from neonatal mouse brain, which differ developmentally from adult microglia. These differences might impact our current understanding of the role of microglia in CNS development, function, and disease. Methods Cytokine protein secretion was compared in ex vivo P3 and adult microglial cultures after exposure to agonists for three different toll-like receptors (TLR4, lipopolysaccharide [LPS]; TLR7, imiquimod [IMQ]; and TLR9, CpG Oligodeoxynucleotide [CpG-ODN] 1585). In addition, changes in inflammatory gene expression in ex vivo adult microglia in response to the TLR agonists was assessed. Furthermore, in vivo experiments evaluated changes in gene expression associated with inflammation and TLR signaling in brains of mice with or without treatment with PLX5622 to reduce microglia. Results Ex vivo adult and P3 microglia increased cytokine secretion when exposed to TLR4 agonist LPS and to TLR7 agonist IMQ. However, adult microglia decreased expression of numerous genes after exposure to TLR 9 agonist CpG-ODN 1585. In contrast, in vivo studies indicated a core group of inflammatory and TLR signaling genes increased when each of the TLR agonists was introduced into the CNS. Reducing microglia in the brain led to decreased expression of various inflammatory and TLR signaling genes. Mice with reduced microglia showed extreme impairment in upregulation of genes after exposure to TLR7 agonist IMQ. Conclusions Cultured adult microglia were more reactive than P3 microglia to LPS or IMQ exposure. In vivo results indicated microglial influences on neuroinflammation were agonist specific, with responses to TLR7 agonist IMQ more dysregulated in mice with reduced microglia. Thus, TLR7-mediated innate immune responses in the CNS appeared more dependent on the presence of microglia. Furthermore, partial responses to TLR4 and TLR9 agonists in mice with reduced microglia suggested other cell types in the CNS can compensate for their absence.

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Host Transcriptional Response to Persistent Infection with a Live-Attenuated Porcine Reproductive and Respiratory Syndrome Virus Strain

Viruses ◽

10.3390/v12080817 ◽

2020 ◽

Vol 12 (8) ◽

pp. 817

Author(s):

Jayeshbhai Chaudhari ◽

Chia-Sin Liew ◽

Aspen M. Workman ◽

Jean-Jack M. Riethoven ◽

David Steffen ◽

...

Keyword(s):

T Cell ◽

Immune Responses ◽

Lymphoid Tissue ◽

Innate Immune ◽

Respiratory Syndrome Virus ◽

Lymphoid Tissues ◽

Innate Immune Responses ◽

Cell Homing ◽

T Cell Homing ◽

Prrsv Strain

Both virulent and live-attenuated porcine reproductive and respiratory syndrome virus (PRRSV) strains can establish persistent infection in lymphoid tissues of pigs. To investigate the mechanisms of PRRSV persistence, we performed a transcriptional analysis of inguinal lymphoid tissue collected from pigs experimentally infected with an attenuated PRRSV strain at 46 days post infection. A total of 6404 differentially expressed genes (DEGs) were detected of which 3960 DEGs were upregulated and 2444 DEGs were downregulated. Specifically, genes involved in innate immune responses and chemokines and receptors associated with T-cell homing to lymphoid tissues were down regulated. As a result, homing of virus-specific T-cells to lymphoid tissues seems to be ineffective, evidenced by the lower frequencies of virus-specific T-cell in lymphoid tissue than in peripheral blood. Genes associated with T-cell exhaustion were upregulated. Likewise, genes involved in the anti-apoptotic pathway were upregulated. Collectively, the data suggested that the live-attenuated PRRSV strain establishes a pro-survival microenvironment in lymphoid tissue by suppressing innate immune responses, T-cell homing, and preventing cell apoptosis.

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