Different Sensitivity of Lamina Propria T-Cell Subsets to Nitric Oxide-Induced Apoptosis Explains Immunomodulatory Activity of a Nitric Oxide--Releasing Derivative of Mesalamine in Rodent Colitis

2005 ◽  
Vol 128 (5) ◽  
pp. 1243-1257 ◽  
Author(s):  
Luca Santucci ◽  
John Wallace ◽  
Andrea Mencarelli ◽  
Silvana Farneti ◽  
Antonio Morelli ◽  
...  
Blood ◽  
2000 ◽  
Vol 96 (1) ◽  
pp. 195-202 ◽  
Author(s):  
Masaki Tateyama ◽  
Naoki Oyaizu ◽  
Thomas W. McCloskey ◽  
Soe Than ◽  
Savita Pahwa

CD4 molecules serve as coreceptors for the T-cell receptor (TCR)/CD3 complex that are engaged coordinately with TCR and facilitate antigen-specific T-cell activation leading to interleukin 2 (IL-2) production and proliferation. However, cross-ligation of CD4 molecules prior to TCR stimulation has been shown to prime CD4 T cells to undergo apoptosis. Although in vivo and in vitro experiments have implicated the involvement of Fas/FasL interaction in this CD4 cross-linking (CD4XL)-induced apoptosis, detailed mechanisms to account for cell death induction have not been elucidated. In the present study, we demonstrate that CD4XL in purified T cells not only led to Fas up-regulation but also primed CD4 T cells to express FasL upon CD3 stimulation and rendered the T cells susceptible to Fas-mediated apoptosis. Notably, in addition to CD4+ T cells, CD4XL-induced sensitization for apoptosis was observed in CD8+ T cells as well and was associated with Bcl-x down-modulation. Both CD4 and CD8 T-cell subsets underwent apoptosis following cell–cell contact with FasL+ CD4 T cells. CD28 costimulation abrogated CD4XL/CD3-induced apoptosis with restoration of IL-2 production and prevented Bcl-x down-modulation. As CD4 molecules are the primary receptors for human immunodeficiency virus 1 (HIV-1), we conclude that HIV-1 envelope mediated CD4XL can lead to the generation of FasL-expressing CD4+ T cells that can lead to apoptosis of CD4 as well as CD8 T cells. These findings implicate a novel mechanism for CD8 T-cell depletion in HIV disease.


2010 ◽  
Vol 1 (4) ◽  
pp. 317-326 ◽  
Author(s):  
M. Meijerink ◽  
J. Wells

Over the past decade it has become clear that probiotic and commensal interactions with mucosal dendritic cells in the lamina propria or epithelial cells lining the mucosa can modulate specific functions of the mucosal immune system. Innate pattern-recognition receptors such as TLRs, NLRs and CLRs play a crucial role in the host recognition of probiotics and other microorganism. Signalling via these receptors directly influences the chemokine and cytokine response of dendritic cells as well as the crosstalk between the epithelium and the immune cells in the lamina propria. This can influence the population of effector and regulatory T cell subsets in the mucosa. Immune assays with probiotics have shown that the in vitro immune response is both species and strain-specific. Such assays may be useful for the selection of probiotic strains that have beneficial effects on the regulation of intestinal inflammation but more comparative studies are needed to confirm recent findings. A better understanding of the molecular mechanisms of probiotics, the effect of dose, and frequency of administration on microbial sampling by mucosal APC will also help to clarify the value of immune assays as selection criteria for probiotics.


Blood ◽  
1995 ◽  
Vol 86 (11) ◽  
pp. 4199-4205 ◽  
Author(s):  
M Brunetti ◽  
N Martelli ◽  
A Colasante ◽  
M Piantelli ◽  
P Musiani ◽  
...  

Glucocorticoid (GC)-induced apoptosis is a well-recognized physiologic regulator of murine T-cell number and function. We have analyzed its mechanisms in human mature T cells, which have been thought to be insensitive until recently. Peripheral blood T cells showed sensitivity to GC-induced apoptosis soon after the proliferative response to a mitogenic stimulation, and were also sensitive to spontaneous (ie, growth factor deprivation-dependent) apoptosis. CD8+ T cells were more sensitive to both forms than CD4+ T cells. Acquisition of sensitivity to GC-induced apoptosis was not associated with any change in number or affinity of GC receptors. Both spontaneous and GC-induced apoptosis were increased by the macromolecular synthesis inhibitors, cycloheximide (CHX) and puromycin. A positive correlation between the degree of protein synthesis inhibition and the extent of apoptosis was observed. Interleukin-2 (IL-2) IL-4, and IL-10 protected (IL-2 > IL-10 > IL-4) T cells from both forms of apoptosis in a dose-dependent manner. Our data suggest that spontaneous and GC-induced apoptosis regulate the human mature T-cell repertoire by acting early after the immune response and differentially affecting T-cell subsets.


2002 ◽  
Vol 195 (1) ◽  
pp. 135-141 ◽  
Author(s):  
Daniel J. Campbell ◽  
Eugene C. Butcher

Effector and memory T cells can be subdivided based on their ability to traffic through peripheral tissues such as inflamed skin and intestinal lamina propria, a property controlled by expression of ‘tissue-specific’ adhesion and chemoattractant receptors. However, little is known about the development of these selectively homing T cell subsets, and it is unclear whether activation in cutaneous versus intestinal lymphoid organs directly results in effector/memory T cells that differentially express adhesion and chemoattracant receptors targeting them to the corresponding nonlymphoid site. We define two murine CD4+ effector/memory T cell subsets that preferentially localize in cutaneous or intestinal lymphoid organs by their reciprocal expression of the adhesion molecules P-selectin ligand (P-lig) and α4β7, respectively. We show that within 2 d of systemic immunization CD4+ T cells activated in cutaneous lymph nodes upregulate P-lig, and downregulate α4β7, while those responding to antigen in intestinal lymph nodes selectively express high levels of α4β7 and acquire responsiveness to the intestinal chemokine thymus-expressed chemokine (TECK). Thus, during an immune response, local microenvironments within cutaneous and intestinal secondary lymphoid organs differentially direct T cell expression of these adhesion and chemoattractant receptors, targeting the resulting effector T cells to the inflamed skin or intestinal lamina propria.


Blood ◽  
2000 ◽  
Vol 96 (1) ◽  
pp. 195-202 ◽  
Author(s):  
Masaki Tateyama ◽  
Naoki Oyaizu ◽  
Thomas W. McCloskey ◽  
Soe Than ◽  
Savita Pahwa

Abstract CD4 molecules serve as coreceptors for the T-cell receptor (TCR)/CD3 complex that are engaged coordinately with TCR and facilitate antigen-specific T-cell activation leading to interleukin 2 (IL-2) production and proliferation. However, cross-ligation of CD4 molecules prior to TCR stimulation has been shown to prime CD4 T cells to undergo apoptosis. Although in vivo and in vitro experiments have implicated the involvement of Fas/FasL interaction in this CD4 cross-linking (CD4XL)-induced apoptosis, detailed mechanisms to account for cell death induction have not been elucidated. In the present study, we demonstrate that CD4XL in purified T cells not only led to Fas up-regulation but also primed CD4 T cells to express FasL upon CD3 stimulation and rendered the T cells susceptible to Fas-mediated apoptosis. Notably, in addition to CD4+ T cells, CD4XL-induced sensitization for apoptosis was observed in CD8+ T cells as well and was associated with Bcl-x down-modulation. Both CD4 and CD8 T-cell subsets underwent apoptosis following cell–cell contact with FasL+ CD4 T cells. CD28 costimulation abrogated CD4XL/CD3-induced apoptosis with restoration of IL-2 production and prevented Bcl-x down-modulation. As CD4 molecules are the primary receptors for human immunodeficiency virus 1 (HIV-1), we conclude that HIV-1 envelope mediated CD4XL can lead to the generation of FasL-expressing CD4+ T cells that can lead to apoptosis of CD4 as well as CD8 T cells. These findings implicate a novel mechanism for CD8 T-cell depletion in HIV disease.


2020 ◽  
Vol 8 (1) ◽  
pp. e000958 ◽  
Author(s):  
Yousef Badran ◽  
Angela Shih ◽  
Donna Leet ◽  
Meghan J Mooradian ◽  
Alexandra Coromilas ◽  
...  

BackgroundRare cases of immune checkpoint inhibitor (ICI)-associated celiac disease (ICI-CeD) have been reported, suggesting that disruption of tolerance mechanisms by ICIs can unmask celiac disease (CeD). This study aims to characterize the clinicopathological and immunophenotypic features of ICI-CeD in comparison to ICI-associated duodenitis (ICI-Duo) and usual CeD.MethodsA medical and pathological records search between 2015 and 2019 identified eight cases of ICI-CeD, confirmed by tTG-IgA. Nine cases of ICI-Duo, 28 cases of moderate CeD, as well as 5 normal controls were used as comparison groups. Clinical information was collected from the electronic medical records. Immunohistochemistry for CD3, CD8, T-cell receptor gamma/delta (γδ), programmed death ligand 1 (PD-L1), and programmed death 1 (PD-1) were performed, with quantification of intraepithelial lymphocyte (IEL) subsets in three well-oriented villi. CD68, PD-L1, and PD-1 were assessed as a percentage of lamina propria surface area infiltrated by positive cells. Statistical significance was calculated by the Student’s t-test and Fisher’s exact test.ResultsThe eight patients with ICI-CeD (F:M=1:3) and nine patients with ICI-Duo (F:M=5:4) presented similarly with diarrhea (13/17) and abdominal pain (11/17) after a median of 1.6 months on ICI therapy. In patients with ICI-CeD, tTG-IgA ranged from 104 to >300 IU/mL. Histological findings in ICI-CeD and ICI-Duo were similar and included expansion of the lamina propria, active neutrophilic duodenitis, variably increased IELs, and villous blunting. Immunohistochemistry showed that the average number of IELs per 100 enterocytes is comparable between ICI-CeD and ICI-Duo, with increased CD3+ CD8+ T cells compared with normal duodenum but decreased γδ T cells compared with CeD. Average PD-L1 percentage was 9% in ICI-CeD and 18% in ICI-Duo, in comparison to <1% in CeD and normal duodenum; average PD-1 percentage was very low to absent in all cases (<3%). On follow-up, five patients with ICI-CeD improved on a gluten-free diet (GFD) as the sole therapeutic intervention (with down-trending tTG-IgA) while the other three required immunosuppression. All patients who developed ICI-Duo received immunosuppression with variable improvement in symptoms.ConclusionsICI-CeD resembles ICI-Duo clinically and histologically but shares the serological features and response to gluten withdrawal with classic CeD. Immunophenotyping of IELs in ICI-CeD and ICI-Duo also shows similar CD3, CD8, γδ T cell subsets, and PD-L1 populations, all of which differed quantitatively from usual CeD. We conclude that ICI-CeD is biologically similar to ICI-Duo and is likely a variant of ICI-Duo, but treatment strategies differ, with ICI-CeD often improving with GFD alone, whereas ICI-Duo requires systemic immunosuppression.


2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S182-S183
Author(s):  
B Roosenboom ◽  
C Horjus Talabur Horje ◽  
C Smids ◽  
J W Leeuwis ◽  
E Van Koolwijk ◽  
...  

Abstract Background Immunotherapy-related colitis is a frequent adverse event in patients with malignancies, treated with inhibitors targeting programmed death-1 (PD-1). This treatment leads to enhancement of lymphocyte activity, thereby generating antitumor T-cell activity. The role of PD-1+ T cells in the pathophysiology of different types of colitis is unclear. Therefore, we aimed to study the presence of PD-1+ T cells in inflammatory bowel disease (IBD), infectious colitis and healthy controls compared with anti-PD-1-related colitis. Methods We performed a prospective cohort study. Newly diagnosed patients with ulcerative colitis (UC, n = 51), Crohn’s disease (CD, n = 29), infectious colitis (n = 4), anti-PD-1-related colitis (n = 5) and healthy controls (n = 6) were included. Baseline colonic biopsy specimens were collected for immunohistochemistry identifying PD-1+ and PD-L1+ lymphocytes in the epithelium and lamina propria separately and for immunophenotyping by flow cytometry identifying PD-1+ T-cell subsets. Results Using immunohistochemistry, PD-1 was not present on lymphocytes in the epithelium of patients with any type of colitis, nor in healthy controls. Of all lymphocytes in the lamina propria, % PD-1 expression was 40% in UC, 5% in infectious colitis, 3% in anti-PD-1-related colitis and 0% in healthy controls. PD-L1 was expressed on lymphocytes in the epithelium and lamina propria of UC patients (12.5% and 40%) and in infectious colitis (1% and 30%), whereas in anti-PD-1-related colitis (0% and 15%) and healthy controls (0% and 15%) no PD-L1+ lymphocytes were demonstrated in the epithelium. Flowcytometry showed higher percentages of PD-1+ T cells in biopsy specimens of UC patients (25.2% (IQR 17.9–35.6)) compared with all other groups; CD patients (13.5% (5.0–25.3), p = 0.001), infectious colitis (9.8% (4.7–17.4), p = 0.005), anti-PD-1-related colitis (1.5% (1.1–2.1), p = 0.001) and healthy controls (14.3% (4.9–28.2), p = 0.08). In IBD and infectious colitis, the majority of PD-1+ T cells were CD4+ (84.8% (76.5–90.5), while in anti-PD-1-related colitis the majority of PD-1+ T cells were CD8+ (76.2% (68.5–82.1)). PD-1+ T cells in all patient groups were mainly effector T cells (CD45Ro+). Conclusion In patients with different types of colitis and in healthy controls, PD-1 was only expressed on T cells in the lamina propria and not in the epithelium. The percentage of PD-1+ T cells was significantly higher in patients with UC compared with patients with CD or infectious colitis and healthy controls. As expected PD-1+ T cells were nearly absent in patients with anti-PD-1-related colitis.


Parasitology ◽  
2017 ◽  
Vol 145 (3) ◽  
pp. 292-306 ◽  
Author(s):  
MANISH K. SINGH ◽  
FAUZIA JAMAL ◽  
AMIT K. DUBEY ◽  
PUSHKAR SHIVAM ◽  
SARITA KUMARI ◽  
...  

SUMMARYImmunoactivation depends upon the antigen potential to modulate T-cell repertoires. The present study has enumerated the effect of 61 kDa recombinant Leishmania donovani co-factor-independent phosphoglycerate mutase (rLd-iPGAM) on mononuclear cells of healthy and treated visceral leishmaniasis subjects as well as on THP-1 cell line. rLd-iPGAM stimulation induced higher expression of interleukin-1β (IL-1β) in the phagocytic cell, its receptor and CD69 on T-cell subsets. These cellular activations resulted in upregulation of host-protective cytokines IL-2, IL-12, IL-17, tumour necrosis factor-α and interferon-γ, and downregulation of IL-4, IL-10 and tumour growth factor-β. This immune polarization was also evidenced by upregulation of nuclear factor-κ light-chain enhancer of activated B cells p50 and regulated expression of suppressor of mother against decapentaplegic protein-4. rLd-iPGAM stimulation also promoted lymphocyte proliferation and boosted the leishmaniacidal activity of macrophages by upregulating reactive oxygen species. It also induced 1·8-fold higher release of nitric oxide (NO) by promoting the transcription of inducible nitric oxide synthase gene. Besides, in silico analysis suggested the presence of major histocompatibility complex class I and II restricted epitopes, which can proficiently trigger CD8+ and CD4+ cells, respectively. This study reports rLd-iPGAM as an effective immunoprophylactic agent, which can be used in future vaccine design.


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