MiR-155 Impacts T Cell Migration in Acute Graft-Versus-Host Disease (aGVHD)

Abstract Introduction: We reported that microRNA-155 (miR-155) expression is upregulated in donor T cells during aGVHD and mice receiving miR-155 knock-out (KO) donor splenocytes do not exhibit lethal GVHD and have improved survival as compared to mice receiving wild type (WT) splenocytes.1 While we showed that miR-155 does not affect the allo-reactive proliferative potential of T cells, a significant decrease in the expression of the homing receptors CCR5, CXCR4, and S1P1 was found on miR-155-KO T cells, suggesting that the loss of miR-155 could impair the migration of donor T cells to aGVHD target organs resulting in less lethality. Here, we further investigate the impact of miR-155 expression in T cell migration. Materials and Methods: Lethally irradiated BALB/c or B6D2F1 recipients were infused with T cell depleted WT bone marrow (BM) cells (5x10^6) and GFP expressing miR-155 KO or GFP-B6 WT T cells (1x10^6). Recipients were sacrificed at day 7, 14 and 21 post-transplant, organs harvested and donor T cell infiltration evaluated via confocal microscopy. Transwell migration assays towards CCR5 ligands macrophage inflammatory protein-1a (MIP-1a) (100ng/mL) and RANTES (100ng/mL) was performed utilizing WT or miR-155-KO T cells activated using irradiated BALB/c splenocytes as allogeneic stimulators at a stimulator: responder ratio of 1:5. Lower chambers with medium only served as a control for spontaneous migration. CCR5 ligand-dependent migration was calculated according to the formula: Migration Index (MI) = number of cells CCR5 ligands / number of cells medium only. Results: On days 7, 14 and 21 post transplant, recipient mice were sacrificed, and tissues harvested in order to study the kinetics of miR-155 KO T cell migration following allogeneic hematopoietic stem cell transplant. There was a dramatic decrease in T cell infiltration of peripheral organs (PeyerÕs patches, liver, lung and skin) in recipients of miR-155-KO T cells as compared to WT T cells as evidenced by confocal microscopy of GFP labeled donor cells, Figure 1. We reasoned that these effects could be due to the modulation of CCR5 and other chemokine receptors by miR-155. There was a significant decrease in CCR5 mRNA and protein expression in miR-155-KO versus WT donor T cells obtained from recipient mice at the time of aGVHD. To demonstrate the functional significance of decreased CCR5 expression in miR-155 KO donor T cells, we performed in vitro transwell migration assays to CCR5 ligands RANTES and MIP-1a. To our knowledge, we are the first to show that allo-activated miR-155 KO T cells show significantly reduced migration towards CCR5 ligands, as demonstrated by the average MI of 1.08, when compared to the average MI of WT T cells of 4.79, p=0.004, Figure 2. There were lower percentages of CCR5 positive T cells and decreased mean fluorescent intensity in the miR-155 KO T cells after allogeneic stimulation when compared to WT T cells, both in the CD4+ and CD8+ populations, confirming lower CCR5 expression in miR-155 KO T cells after in vitro allogeneic stimulation. To further elucidate the mechanism of miR-155 mediated modulation of CCR5 expression, we focused on long non-coding RNA (lncRNA) LincR-Ccr2-5′AS located in the vicinity of several chemokine receptor encoding genes including CCR1, CCR2 and CCR5, known to be important for migration of Th2 cells. We found that LincR-Ccr2-5′AS has 3 potential miR-155 binding sites and so set out to determine if miR-155 negatively regulates the expression of this lncRNA, thereby influencing chemokine receptor expression as well as T cell migration. We isolated T cells from B6D2F1 recipients 21 days post-transplant, and showed a significant decrease in CCR5 mRNA expression in miR-155 KO versus WT donor T cells but no significant difference in the levels of LincR-Ccr2-5′AS. However, this result does not exclude the possibility that miR-155 might influence the activity rather than the levels of LincR-Ccr2-5′AS, which we hope to determine in future experiments. Conclusion: Our data suggest that miR-155 may exert its modulating effects in aGVHD by affecting T cell migration. Experiments are currently underway to determine the role of miR-155 in modulating T cell migration through other chemokine receptors such as CXCR4, as well as S1P1 and ATP receptor P2X7R. Reference 1. Ranganathan P, Heaphy CE, Costinean S, et al. Regulation of acute graft-versus-host disease by microRNA-155. Blood. 2012 May 17;119(20):4786-97. Disclosures No relevant conflicts of interest to declare.

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Form and pattern of MUC1 expression on T cells activated in vivo or in vitro suggests a function in T-cell migration

Immunology ◽

10.1046/j.1365-2567.2003.01562.x ◽

2003 ◽

Vol 108 (1) ◽

pp. 32-41 ◽

Cited By ~ 46

Author(s):

Isabel Correa ◽

Tim Plunkett ◽

Anda Vlad ◽

Arron Mungul ◽

Jessica Candelora-Kettel ◽

...

Keyword(s):

T Cells ◽

Cell Migration ◽

T Cell ◽

Muc1 Expression ◽

T Cell Migration

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Definition of a Diagnostic Window Prior to the Onset of Clinically Apparent Acute Graft-Versus-Host Disease.

Blood ◽

10.1182/blood.v116.21.3746.3746 ◽

2010 ◽

Vol 116 (21) ◽

pp. 3746-3746

Author(s):

Carina A Bäuerlein ◽

Simone S Riedel ◽

Brede Christian ◽

Ana-Laura Jordán Garrote ◽

Agnes Birner ◽

...

Keyword(s):

T Cells ◽

Cell Migration ◽

T Cell ◽

Cd8 T Cells ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Critical Time ◽

Time Points ◽

T Cell Migration ◽

Donor T Cells

Abstract Abstract 3746 Acute graft-versus-host disease (aGvHD) is an immune syndrome after allogeneic hematopoietic cell transplantation (allo-HCT) caused by alloreactive donor T cells that attack the gastrointestinal tract, liver and skin. Thus, early T cell migration patterns to these organs could provide first cues for the onset of aGvHD. Hence, a unique surface marker profile of donor T cells at early time points after allo-HCT may be an indicator for patients at risk of aGVHD. Therefore, we analyzed the course of donor T cell activation, proliferation and homing in a clinical relevant murine MHC minor mismatch (miHAg) allo-HCT model to define critical time points and marker profiles for the detection of alloreactive T cells. Luciferase-labeled C57Bl/6 (H-2b) T cells plus bone marrow cells were transplanted into conditioned (8 Gy) MHC major mismatched Balb/c (H-2d) or miHAg Balb/b (H-2b) recipients. Donor T cell migration was visualized by in vivo bioluminescence imaging (BLI) and cells were characterized by multiparameter flow cytometry for 30 consecutive days after allo-HCT. GVHD scoring was performed by histopathology. Donor T cells proliferated exclusively in secondary lymphoid organs until day+3 (initiation phase) before migrating via the peripheral blood into target organs (effector phase). This occured in both models, MHC major mismatch and miHAg allo-HCT, which resulted in hyper-acute (starting at day+6) or acute GVHD (starting at day+21), respectively. In the hyper-acute scenario one wave of T cell migration starting at day+4 sufficed to cause lethal aGVHD. We detected a 4000-fold increase in CD4 and a 1500-fold increase in CD8 donor T cell numbers in the peripheral blood between day+3 and day+6 in this model. In contrast, in the more clinical relevant miHAg allo-HCT model we found 3 waves of T cell migration with peaks at days +6, +11 and +15 after allo-HCT. In the peripheral blood CD4 T cells increased 20-fold, CD8 T cells 50-fold between day+3 and day+6, but more than 40-fold (CD4) and 400-fold (CD8) between day+3 and day+11. After the third peak on day+15 a period followed when we could only detect very few migrating donor T cells in the peripheral blood before aGvHD became clinically apparent on day+21. Next, we asked whether we could identify alloreactive T cells by testing a large panel of surface markers at the defined migration peaks. Indeed, allogeneic T cells upregulated certain homing receptors at these peaks (e.g. at day+11: α4β7 integrin: 27% of CD4 T cells, 3.4×104/ml, 60% of CD8 T cells, 1.6×105/ml; P-selectin ligand: 28% of CD4 T cells, 3.5×104/ml, 35% of CD8 T cells, 9.1×104/ml). In contrast, syngeneic transplanted mice only showed a constant low expression level of those receptors (e.g. at day+11: α4β7 integrin: 20% of CD4 T cells, 9.6×103/ml, 5% of CD8 T cells, 3.1×103/ml; P-selectin ligand: 17% of CD4 T cells, 8.5×103/ml, 10% of CD8 T cells, 6.6×103/ml). However, other markers such as CD44 could be found on more than 80% of all donor T cells in allogeneic or syngeneic recipients. Our results in this clinical relevant mouse model show accelerating waves of T cell migration consistent with an enhancing feedback loop model of aGvHD pathogenesis. The homing receptor expression profile of donor T cells correlated with critical migration waves and clearly differed between mice with or without aGvHD. The assessment of critical time points frame a diagnostic window for a potential predictive test based on the dynamic change of the T cell homing receptor profile after allo-HCT. This preclinical study now awaits to be evaluated in patients undergoing allo-HCT. Disclosures: No relevant conflicts of interest to declare.

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Protein kinase C: a regulator of cytoskeleton remodelling and T-cell migration

Biochemical Society Transactions ◽

10.1042/bst20140204 ◽

2014 ◽

Vol 42 (6) ◽

pp. 1490-1497 ◽

Cited By ~ 7

Author(s):

Aideen Long ◽

Michael Freeley

Keyword(s):

T Cells ◽

Protein Kinase C ◽

Cell Migration ◽

T Cell ◽

Protein Kinase ◽

Immune Responses ◽

Chemokine Receptors ◽

T Cell Subsets ◽

T Cell Migration ◽

Kinase C

Protein kinase C (PKC) is a family of ten serine/threonine kinases that have diverse roles in the signalling pathways regulating cellular proliferation, differentiation, apoptosis and immune responses. Elucidating roles for individual PKC isoforms in the immune responses of T-cells have long been a challenging prospect, because these cells are known to express nine of these isoforms. A variety of approaches including the use of knockout mice, overexpression of kinase-inactive mutants, cell-permeable peptides, pharmacological inhibitors and siRNAs have shown that PKCs regulate the production of inflammatory cytokines and the cytotoxic responses of various T-cell subsets. Central to the T-cell immune response is a requirement to migrate to various organs and tissues in search of pathogens and micro-organisms. T-cell migration is guided by specific sets of chemokines and integrin ligands that activate their cognate chemokine receptors and integrins on T-cells, resulting in remodelling of the cytoskeleton and the dynamic protrusive/contractile forces necessary for cell adhesion and motility. In the present article, we review the role of PKC in T-cell migration, with an emphasis on studies that have defined their roles in cytoskeletal remodelling, cell polarity and intracellular trafficking downstream of chemokine receptors and integrins.

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Donor Plasmacytoid Dendritic Cells Regulate GvHD in a VIP Dependent Manner in Allogeneic BMT Recipients

Blood ◽

10.1182/blood-2021-152945 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 1687-1687

Author(s):

Jingru Zhu ◽

Pankoj Kumar Das ◽

Yitong Wang ◽

Jingxia Li ◽

Tamas Nagy ◽

...

Keyword(s):

Cell Proliferation ◽

T Cells ◽

Dendritic Cells ◽

T Cell ◽

Gene Expression Analysis ◽

T Cell Proliferation ◽

Post Transplant ◽

Donor T Cells ◽

Th1 Polarization

Abstract Introduction: Vasoactive intestinal peptide (VIP) is an anti-inflammatory neuropeptide known to induce differentiation of regulatory dendritic cells and regulatory T cells. Using allogeneic hematopoietic stem cell transplantation (allo-HSCT) models, we have shown that donor bone marrow (BM) plasmacytoid dendritic cells (pDCs) facilitate HSC engraftment and attenuate pathogenesis of graft vs. host disease (GvHD) through regulation of recipient T cells. However, the mechanism by which pDCs mitigate the GvHD activity of recipient T cells is not clearly understood. Here, we report that donor pDCs limit pathogenic T cell inflammation by VIP production. Methods: To study VIP production by pDCs, FACS-sorted pDCs from B6 mouse BM were cultured with or without PMA/ionomycin in-vitro. After activation and cytospin slide preparation, pDCs were labeled with anti-PDCA1 (pDC marker) and anti-VIP antibodies for confocal fluorescence microscopy. To investigate the effects of VIP production on T cell proliferation, an in-vitro co-culture assay was performed using R848 and CpG-activated WT or VIP-KO pDCs with anti-CD3-activated, CFSE-labeled syngeneic T cells. For GvHD experiments, irradiated B10.BR (H-2K k) mice received 5x10 3 HSCs, 5x10 4 pDCs and 1x10 6 T cells from WT B6 (H-2K b) or VIP-KO B6 (H-2K b) mice. H&E histology of intestine and colon was performed for GvHD scoring 7 days post-transplant. Graft vs. leukemia (GvL) effects were tested by inoculating recipient mice with 5x10 5 LBRM 33-5A4 cells in the same model. Recipient mice were monitored twice weekly using a 10-point GvHD scoring system. Gene expression analysis of FACS-sorted donor T-cells from recipient spleens was performed using the Nanostring Myeloid Innate Immunity Panel at days 8 and 15 post-transplant. Results: Confocal microscopic images of PMA/ionomycin stimulated or unstimulated sorted pDCs show that VIP is synthesized by pDCs (anti-VIP, green; anti-PCDA-1, red; DAPI counterstain, blue) (Fig 1). After in-vitro culture, VIP expression and frequencies of VIP + pDCs were similar in PMA/ionomycin treated or untreated cells (not shown). VIP-KO mice have significantly higher percentages of pDCs in BM compared to WT (Fig 2a). T cells co-cultured with VIP-KO pDCs showed higher proliferation than T cells co-cultured with WT pDCs, demonstrating that VIP secreted by pDCs reduces T cell proliferation (Fig 2b). Moreover, VIP-KO pDCs induce significantly greater proliferation of IFN-gamma + CD8 T cells compared to WT, indicating that pDCs lacking VIP promote Th1 polarization in-vitro (Fig 2c). The data are consistent with results from GvHD experiments showing increased frequencies of Th1 polarized T cells and fewer regulatory T cells in recipients of VIP-KO pDCs compared with recipients of WT pDCs. Intestinal GvHD scores and crypt apoptosis in the colon were higher in recipient groups transplanted without pDCs or with VIP-KO pDCs compared with recipients of WT pDCs (Fig 3a, b, c). These results indicate that VIP secreted from pDCs limits GvHD in the gut. In the GvL model, administration of pDCs lacking VIP did not alter the anti-tumor effect of donor T cells. Nanostring analysis of T cells recovered from VIP-KO pDC recipients had increased expression of the pro-inflammatory transcription factor Bhlhe40 during the first two weeks post-transplant, and higher transcription levels of the inflammatory mediator Cyclophilin A at day 15 post-transplant than T cells from recipients of WT pDCs. Conclusion: Data from in vitro and in vivo experiments suggest that VIP secreted by pDCs limits pathogenic T cell proliferation. In murine allo-BMT, increased gut GvHD scores and crypt apoptosis in recipients transplanted without pDCs or with VIP-KO pDCs indicates that VIP secreted by pDCs consolidates gut integrity without altering GvL. Gene expression analysis also supports a mechanism by which VIP-secreting donor pDCs reduce T cell inflammation through negative regulation of Bhlhe40. Our findings suggest paracrine VIP signaling is a novel immune checkpoint pathway by which donor pDCs limit T cell activation, Th1 polarization, and inflammation, and improve outcomes of allo-BMT by reducing GvHD activity. Figure 1 Figure 1. Disclosures Waller: Cambium Oncology: Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company; Verastem Oncology: Consultancy, Research Funding.

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T-Bet Is Critical for the Development of Acute Graft-Versus-Host Disease Through Controlling T Cell Differentiation and Function

Blood ◽

10.1182/blood.v120.21.452.452 ◽

2012 ◽

Vol 120 (21) ◽

pp. 452-452

Author(s):

Jianing Fu ◽

Dapeng Wang ◽

Yu Yu ◽

Kane Kaosaard ◽

Chen Liu ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd4 T Cells ◽

Th17 Cells ◽

Acute Gvhd ◽

T Cell Infiltration ◽

Target Organs ◽

Donor T Cells ◽

Ifn Γ

Abstract Abstract 452 Background: Allogeneic hematopoietic cell transplantation (HCT) offers great promise for the treatment of hematologic malignancies. However, HCT benefits are frequently offset by graft-versus-host disease (GVHD). Donor T cells can differentiate into Th1 or Th17 subset that contribute to GVHD. The T-box transcription factor T-bet is important for promoting the differentiation of naïve CD4+T cells into Th1 phenotype, while simultaneously inhibiting Th2 and Th17 lineage commitment. Published data indicate that donor T cells deficient for IFN-γ induce exacerbated GVHD. In contrast, our recent study showed that T cells deficient for T-bet were impaired in the induction of GVHD. Given T-bet is a master regulator for the differentiation into Th1 cells that produce IFN-γ, the underlining mechanisms accounted for the distinct outcomes caused by T-bet- versus IFN-γ-deficient donor T cells are not clear. Method: We evaluated the roles of T-bet and IFN-γ in acute GVHD induced by naïve CD4+ T cells or polarized Th17 cells using murine allogeneic bone marrow transplantation (allo-BMT) model. WT, T-bet knockout (KO) and IFN-γ KO mice on C57BL/6 (B6) background were used as donors, and lethally irradiated BALB/c mice were used as recipients. Pathologic analysis and serum cytokine detection were done 14 days after adoptive transfer of WT, T-bet–/–, and IFN-γ–/– CD4+ T cells. Using microarray technology, gene expression profile on donor T cells was analyzed 7 days after adoptive transfer by sorting donor-derived CD4+ T cells from the recipients of WT, T-bet–/– or IFN-γ–/– CD4+ T cells. Results: We compared the ability of WT, T-bet–/–, and IFN-γ–/– CD4 T cells in the induction of acute GVHD. In the comparison with WT cells, IFN-γ–/– CD4 T cells caused similar or even more severe GVHD as expected. In sharp contrast, T-bet–/– CD4 T cells induced much ameliorated GVHD, as significantly higher survival and less body weight loss were observed in the recipients of T-bet–/–T cells. Pathology study on GVHD target organs showed that recipients of T-bet–/– donor T cells had markedly reduced T cell infiltration and tissue damage in liver, gut, and skin, when compared with those of WT or IFN-γ–/– T cells. Reduced GVHD in the recipients of T-bet–/– T cells was consistent with significantly lower levels of pathogenic cytokines IFN-γ, TNF-α, and IL-2 but higher IL-10 (anti-inflammatory), IL-6 (Th17 related) and IL-4 (Th2 related) in serum as compared with those in the recipients of WT T cells. Mechanistic studies in vitro revealed that T-bet–/– CD4 T cells expressed significantly lower levels of IFN-γ, CXCR3 (Th1 specific chemokine receptor) and CD122 (T cell activation marker), but higher levels of IL-17 (Th17 cytokine) and CCR6 (Th17 specific chemokine receptor) compared with WT CD4 T cells, indicating that T-bet–/– T cells impaired in differentiating into Th1 cells and instead into Th17 cells. Given Th17 subset only is capable of causing GVHD and T-bet–/– T cells are prone to Th17-differentiation, we assessed the role of T-bet or IFN-γ in the development of GVHD by comparing the pathogenicity of in vitro polarized WT, T-bet–/– and IFN-γ–/– Th17 cells. While IFN-γ–/– Th17 cells had a comparable ability to cause GVHD compared with WT Th17 cells, T-bet–/– Th17 cells had reduced pathogenicity, and caused ameliorated GVHD. Furthermore, microarray analysis identified genes that are regulated by T-bet but independent of IFN-γ, including Cxcr3, Ccr5, Ccl3, Ccl4, Klrc1, Klrd1, Nkg7 and Pdcd1, which may explain the compromised ability of T-bet−/− not IFN-γ–/–T cells in the induction of GVHD. Conclusions: We conclude that T-bet is required for Th1 differentiation and optimal function of Th17 cells, and it can also control T cell infiltration into GVHD target organs by regulating chemokines and their receptors. Thus, failure in Th1 generation, migration and reduced activity of polarized Th17 cells are likely accounted for impaired ability of T-bet−/− CD4 T cells in the induction of acute GVHD. The current study suggests that targeting T-bet or regulating its downstream effectors independent of IFN-γ may be a promising strategy to control GVHD after allogeneic HCT in clinic. Disclosures: No relevant conflicts of interest to declare.

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CrkL is required for donor T cell migration to GvHD Target organs

10.1101/854042 ◽

2019 ◽

Author(s):

Nathan H. Roy ◽

Mahinbanu Mammadli ◽

Janis K. Burkhardt ◽

Mobin Karimi

Keyword(s):

T Cells ◽

Cell Migration ◽

T Cell ◽

Adaptor Protein ◽

Cell Transplant ◽

Hematopoietic Stem ◽

Peripheral Tissues ◽

T Cell Migration ◽

Related Family

ABSTRACTThe success of cancer therapies based on allogeneic hematopoietic stem cell transplant relies on the ability to separate graft-versus-host disease (GvHD) from graft-versus-tumor (GVT) responses. Controlling donor T cell migration into peripheral tissues is a viable option to limit unwanted tissue damage, but a lack of specific targets limits progress on this front. Here, we show that the adaptor protein CrkL, but not the closely related family members CrkI or CrkII, is a crucial regulator of T cell migration. In vitro, CrkL-deficient T cells fail to polymerize actin in response to the integrin ligand ICAM-1, resulting in defective migration. Using a mouse model of GvHD/GVT, we found that while CrkL-deficient T cells can efficiently eliminate hematopoietic tumors they are unable to migrate into inflamed organs, such as the liver and small intestine, and thus do not cause GvHD. These results suggest a specific role for CrkL in trafficking to peripheral organs but not the lymphatic system. In line with this, we found that although CrkL-deficient T cells could clear hematopoietic tumors, they failed to clear the same tumor growing subcutaneously, highlighting the role of CrkL in controlling T cell migration into peripheral tissues. Our results define a unique role for CrkL in controlling T cell migration, and suggest that CrkL function could be therapeutically targeted to enhance the efficacy of immunotherapies involving allogeneic donor cells.

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PLCβ Is Critical for T-Cell Chemotaxis In Vivo.

Blood ◽

10.1182/blood.v104.11.2650.2650 ◽

2004 ◽

Vol 104 (11) ◽

pp. 2650-2650

Author(s):

Tami L. Bach ◽

Qing-Min Chen ◽

Martha S. Jordan ◽

John K. Choi ◽

Dianqing Wu ◽

...

Keyword(s):

T Cells ◽

Cell Migration ◽

T Cell ◽

Chronic Inflammation ◽

Critical Role ◽

Neutrophil Chemotaxis ◽

Wild Type ◽

T Cell Migration

Abstract Chemokines acting through G-protein coupled receptors play an essential role in both the immune and inflammatory responses. Phosphatidylinositol 3-kinase (PI3K) and phospholipase C (PLC) are two distinct signaling molecules that have been proposed as potential candidates in the regulation of this process. Studies with knockout mice have demonstrated a critical role for PI3Kγ, but not PLCβ, in Gαi-coupled receptor-mediated neutrophil chemotaxis. We compared the chemotactic response of peripheral T-cells derived from wild type mice with mice containing loss-of-function mutations of either PI3Kγ, or both of the two predominant lymphocyte PLCβ isoforms (PLCβ2 and PLCβ3). In contrast to neutrophils, loss of PI3Kγ did not significantly impair T-cell migration in vitro, although PI3K pharmacologic inhibitor experiments suggest that another isoform of this enzyme might contribute to T-cell migration. However, loss of PLCβ2β3 decreased chemokine-stimulated T-cell migration in vitro. Chelation of intracellular calcium by BAPTA-AM and Quin-2 AM decreased the chemotactic response of wild type lymphocytes, but pharmacologic inhibition of PKC isoforms by GF109203x did not impair T-cell migration. This suggests that the T-cell migration defect seen in the PLCβ2β3-null T-cells may be due to an impaired ability to increase the cytoplasmic calcium concentration, while there appears to be little requirement for PKC activity. Indeed, SDF-1α-induced calcium efflux was not detected in the PLCβ2β3-null lymphocytes. Compared to fluorescently labeled wild type T-cells, labeled PLCβ2β3 knockout T-cells migrated less efficiently into secondary lymphoid organs of recipient mice. This demonstrates that PLCβ is also required for migration in vivo. PLCβ2β3-null mice develop spontaneous skin ulcers starting around 3 months of age. Histological examination of the lesions revealed a dense inflammatory infiltrate composed of neutrophils, macrophages, and plasma cells, consistent with acute and chronic inflammation. Remarkably, lymphocytes, typical of chronic inflammation, were rare to absent by histology and by paraffin immunohistochemistry for CD3, also consistent with an in vivo migratory defect of T-cells. These results show that phospholipid second messengers generated by PLCβ and isoforms of PI3K, other than PI3Kγ, play a critical role in lymphocyte chemotaxis. Collectively, our data demonstrate that although PLCβ-mediated signaling plays no role in neutrophil chemotaxis, it makes a substantial contribution to this process within T-lymphocytes.

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Biased agonists of the chemokine receptor CXCR3 differentially control chemotaxis and inflammation

Science Signaling ◽

10.1126/scisignal.aaq1075 ◽

2018 ◽

Vol 11 (555) ◽

pp. eaaq1075 ◽

Cited By ~ 12

Author(s):

Jeffrey S. Smith ◽

Lowell T. Nicholson ◽

Jutamas Suwanpradid ◽

Rachel A. Glenn ◽

Nicole M. Knape ◽

...

Keyword(s):

T Cells ◽

Cell Migration ◽

T Cell ◽

G Protein ◽

Chemokine Receptor ◽

Chemokine Receptors ◽

Physiological Responses ◽

T Cell Migration ◽

Biased Signaling ◽

Biased Agonist

The chemokine receptor CXCR3 plays a central role in inflammation by mediating effector/memory T cell migration in various diseases; however, drugs targeting CXCR3 and other chemokine receptors are largely ineffective in treating inflammation. Chemokines, the endogenous peptide ligands of chemokine receptors, can exhibit so-called biased agonism by selectively activating either G protein– or β-arrestin–mediated signaling after receptor binding. Biased agonists might be used as more targeted therapeutics to differentially regulate physiological responses, such as immune cell migration. To test whether CXCR3-mediated physiological responses could be segregated by G protein– and β-arrestin–mediated signaling, we identified and characterized small-molecule biased agonists of the receptor. In a mouse model of T cell–mediated allergic contact hypersensitivity (CHS), topical application of a β-arrestin–biased, but not a G protein–biased, agonist potentiated inflammation. T cell recruitment was increased by the β-arrestin–biased agonist, and biopsies of patients with allergic CHS demonstrated coexpression of CXCR3 and β-arrestin in T cells. In mouse and human T cells, the β-arrestin–biased agonist was the most efficient at stimulating chemotaxis. Analysis of phosphorylated proteins in human lymphocytes showed that β-arrestin–biased signaling activated the kinase Akt, which promoted T cell migration. This study demonstrates that biased agonists of CXCR3 produce distinct physiological effects, suggesting discrete roles for different endogenous CXCR3 ligands and providing evidence that biased signaling can affect the clinical utility of drugs targeting CXCR3 and other chemokine receptors.

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Critical roles for Rac GTPases in T-cell migration to and within lymph nodes

Blood ◽

10.1182/blood-2010-08-299438 ◽

2010 ◽

Vol 116 (25) ◽

pp. 5536-5547 ◽

Cited By ~ 54

Author(s):

Mustapha Faroudi ◽

Miroslav Hons ◽

Agnieszka Zachacz ◽

Celine Dumont ◽

Ruth Lyck ◽

...

Keyword(s):

T Cells ◽

Cell Migration ◽

T Cell ◽

Lymph Nodes ◽

Chemokine Receptors ◽

White Pulp ◽

Multiple Defects ◽

Rac Gtpases ◽

Sphingosine 1 Phosphate

Abstract Naive T cells continuously recirculate between secondary lymphoid tissue via the blood and lymphatic systems, a process that maximizes the chances of an encounter between a T cell and its cognate antigen. This recirculation depends on signals from chemokine receptors, integrins, and the sphingosine-1-phosphate receptor. The authors of previous studies in other cell types have shown that Rac GTPases transduce signals leading to cell migration and adhesion; however, their roles in T cells are unknown. By using both 3-dimensional intravital and in vitro approaches, we show that Rac1- and Rac2-deficient T cells have multiple defects in this recirculation process. Rac-deficient T cells home very inefficiently to lymph nodes and the white pulp of the spleen, show reduced interstitial migration within lymph node parenchyma, and are defective in egress from lymph nodes. These mutant T cells show defective chemokine-induced chemotaxis, chemokinesis, and adhesion to integrin ligands. They have reduced lateral motility on endothelial cells and transmigrate in-efficiently. These multiple defects stem from critical roles for Rac1 and Rac2 in transducing chemokine and sphingosine-1-phosphate receptor 1 signals leading to motility and adhesion.

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THE EFFECT OF GLUTAMATE ON THE MIGRATION OF T CELLS FROM HEALTHY DONORS AND PATIENTS WITH MULTIPLE SCLEROSIS IN VITRO

Medical academic journal ◽

10.17816/maj191s129-30 ◽

2019 ◽

Vol 19 (1S) ◽

pp. 29-30

Author(s):

M A Maksimova ◽

U Sh Kuzmina ◽

K Z Bakhtiyarova ◽

Yu V Vakhitova

Keyword(s):

Multiple Sclerosis ◽

T Cells ◽

Cell Migration ◽

T Cell ◽

Concentration Gradient ◽

Migration Activity ◽

T Cell Migration ◽

Healthy Donors ◽

Glutamate Receptor Agonists

Aim of study. To study chemotactic properties of glutamate and glutamate receptor agonists on T cells migration from healthy donors and patients with multiple sclerosis (MS) in vitro. Materials and methods. T cell migration of 15 patients with MS and 15 healthy donors was studied in vitro using transwells. Lymphocytes were activated with PMA (10 ng/mL). T cells were added to transwells with fibronectin (10 μg/mL) pretreated membrane. The lower chamber contained glutamate or AMPA or NMDA (100 μM for each) in complete RPMI medium. Migrated cells were collected and stained with antibodies to CD3-marker for subsequent analysis by cytofluorimetry. Results and conclusion. In presence of glutamate, there is a tendency to a decrease in migration activity in both groups of donors. T-cell chemotaxis of healthy donors, but not MS patients, decreased in concentration gradient of NMDA. The activation of lymphocytes with PMA leads to a decrease in the number of migrated cells by an average of 17% (p < 0.01). In MS patients there is a tendency to an increase in chemotaxis of activated cells in concentration gradient of glutamate, and a decrease with AMPA. Thus, glutamate and glutamate receptors agonists do not possess pronounced chemotactic properties, but rather enhance T-cell migration through synthesis of adhesion molecules on the surface of lymphocytes and endothelium.

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