scholarly journals In Vivo Interference with Skp1 Function Leads to Genetic Instability and Neoplastic Transformation

2002 ◽  
Vol 22 (23) ◽  
pp. 8375-8387 ◽  
Author(s):  
Roberto Piva ◽  
Jian Liu ◽  
Roberto Chiarle ◽  
Antonello Podda ◽  
Michele Pagano ◽  
...  

ABSTRACT Skp1 is involved in a variety of crucial cellular functions, among which the best understood is the formation together with Cul1 of Skp1-cullin-F-box protein ubiquitin ligases. To investigate the role of Skp1, we generated transgenic (Tg) mice expressing a Cul1 deletion mutant (Cul1-N252) able to sequestrate and inactivate Skp1. In vivo interference with Skp1 function through expression of the Cul1-N252 mutant into the T-cell lineage results in lymphoid organ hypoplasia and reduced proliferation. Nonetheless, after a period of latency, Cul1-N252 Tg mice succumb to T-cell lymphomas with high penetrance (>80%). Both T-cell depletion and the neoplastic phenotype of Cul1-N252 Tg mice are largely rescued in Cul1-N252, Skp1 double-Tg mice, indicating that the effects of Cul1-N252 are due to a sequestration of the endogenous Skp1. Analysis of Cul1-N252 lymphomas demonstrates striking karyotype heterogeneity associated with c-myc amplification and c-Myc overexpression. We show that the in vitro expression of the Cul1-N252 mutant causes a pleiotrophic phenotype, which includes the formation of multinucleated cells, centrosome and mitotic spindle abnormalities, and impaired chromosome segregation. Our findings support a crucial role for Skp1 in proper chromosomal segregation, which is required for the maintenance of euploidy and suppression of transformation.

2021 ◽  
Vol 9 (6) ◽  
pp. 1177
Author(s):  
Abdulaziz Alhazmi ◽  
Magloire Pandoua Nekoua ◽  
Hélène Michaux ◽  
Famara Sane ◽  
Aymen Halouani ◽  
...  

The thymus gland is a primary lymphoid organ for T-cell development. Various viral infections can result in disturbance of thymic functions. Medullary thymic epithelial cells (mTECs) are important for the negative selection of self-reactive T-cells to ensure central tolerance. Insulin-like growth factor 2 (IGF2) is the dominant self-peptide of the insulin family expressed in mTECs and plays a crucial role in the intra-thymic programing of central tolerance to insulin-secreting islet β-cells. Coxsackievirus B4 (CVB4) can infect and persist in the thymus of humans and mice, thus hampering the T-cell maturation and differentiation process. The modulation of IGF2 expression and protein synthesis during a CVB4 infection has been observed in vitro and in vivo in mouse models. The effect of CVB4 infections on human and mouse fetal thymus has been studied in vitro. Moreover, following the inoculation of CVB4 in pregnant mice, the thymic function in the fetus and offspring was disturbed. A defect in the intra-thymic expression of self-peptides by mTECs may be triggered by CVB4. The effects of viral infections, especially CVB4 infection, on thymic cells and functions and their possible role in the pathogenesis of type 1 diabetes (T1D) are presented.


Vaccines ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 631
Author(s):  
Jie Wang ◽  
Katarzyna Urbanska ◽  
Prannda Sharma ◽  
Reza Nejati ◽  
Lauren Shaw ◽  
...  

Peripheral T cell lymphomas (PTCLs) are generally chemotherapy resistant and have a poor prognosis. The lack of targeted immunotherapeutic approaches for T cell malignancies results in part from potential risks associated with targeting broadly expressed T cell markers, namely T cell depletion and clinically significant immune compromise. The knowledge that the T cell receptor (TCR) β chain in human α/β TCRs are grouped into Vβ families that can each be targeted by a monoclonal antibody can therefore be exploited for therapeutic purposes. Here, we develop a flexible approach for targeting TCR Vβ families by engineering T cells to express a chimeric CD64 protein that acts as a high affinity immune receptor (IR). We found that CD64 IR-modified T cells can be redirected with precision to T cell targets expressing selected Vβ families by combining CD64 IR-modified T cells with a monoclonal antibody directed toward a specific TCR Vβ family in vitro and in vivo. These findings provide proof of concept that TCR Vβ-family-specific T cell lysis can be achieved using this novel combination cell–antibody platform and illuminates a path toward high precision targeting of T cell malignancies without substantial immune compromise.


2003 ◽  
Vol 225 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Tazio Storni ◽  
Martin F. Bachmann
Keyword(s):  
T Cell ◽  

PLoS ONE ◽  
2013 ◽  
Vol 8 (6) ◽  
pp. e65308 ◽  
Author(s):  
Qingqing Cai ◽  
Huiqiang Huang ◽  
Dong Qian ◽  
Kailin Chen ◽  
Junhua Luo ◽  
...  

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 3063-3063 ◽  
Author(s):  
S. Whittaker ◽  
W. McCulloch ◽  
T. Robak ◽  
E. Baran

3063 Background: Depsipeptide, a unique bicyclic peptide histone deacetylase inhibitor (HDACi), has shown activity in a range of in vitro and in vivo tumor models and clinical activity in T-cell lymphomas and prostate cancer. This study seeks to confirm the CTCL activity previously reported by the NCI (Piekarz, et al., ASCO, 2004). Methods: Single-arm, open label study, in 25 centers in the UK, Germany, Poland and the US. Patients aged ≥18 years with biopsy-confirmed CTCL (centrally reviewed) who have failed at least one prior systemic treatment receive up to 6 cycles of depsipeptide as a 4-hour IV infusion on Days 1, 8 and 15 q 28 days. Eligibility criteria include: mycosis fungoides and Sézary syndrome plus variants, Stages IB - IVA, adequate organ function, ECOG PS ≤ 1. Patients with significant cardiovascular abnormalities are excluded in addition to those taking QTc-prolonging or CYP3A4-inhibiting drugs. The primary endpoint is overall reponse rate measured by a combination of imaging, circulating cell counts and a weighted skin average instrument, confirmed by standardized photography. A subset undergoes pharmacokinetic assessments. Correlative studies include acetylation status, apoptotic markers and proteomic analyses where possible. Target accrual is 76 to yield 64 evaluable patients. Results: 30 patients have received treatment with 17 evaluable for efficacy. Responses seen are 1 cCR, 4 PRs (duration 2+ to 6 months) 9 SD and 3 PD. 3 patients withdrew early for PD and 2 for other reasons. The remaining patients on study are too early to assess. Most frequent toxicities are: nausea/vomiting, fatigue, myelosuppression and asymptomatic ECG changes. No patient has withdrawn for toxicity and there have been no treatment-related deaths. Conclusions: The previously reported efficacy of depsipeptide in CTCL has also been seen in the present study. Duration of response is encouraging. Toxicity is manageable and the study continues to accrue. [Table: see text]


2005 ◽  
Vol 18 (1) ◽  
pp. 95-100 ◽  
Author(s):  
Thomas M. Bauer ◽  
Lucian P. Jiga ◽  
Jing-Jing Chuang ◽  
Marco Randazzo ◽  
Gerhard Opelz ◽  
...  

2010 ◽  
Vol 208 (1) ◽  
pp. 115-123 ◽  
Author(s):  
Jennifer H. Cox ◽  
Noelyn M. Kljavin ◽  
Nandhini Ramamoorthi ◽  
Lauri Diehl ◽  
Marcel Batten ◽  
...  

Interleukin-27 (IL-27) is a cytokine known to have both proinflammatory and immunoregulatory functions. The latter appear to dominate in vivo, where IL-27 suppresses TH17 responses and promotes the differentiation of Tr1 cells expressing interferon-γ and IL-10 and lacking forkhead box P3 (Foxp3). Accordingly, IL-27 receptor α (Il27ra)–deficient mice suffer from exacerbated immune pathology when infected with various parasites or challenged with autoantigens. Because the role of IL-27 in human and experimental mouse colitis is controversial, we studied the consequences of Il27ra deletion in the mouse T cell transfer model of colitis and unexpectedly discovered a proinflammatory role of IL-27. Absence of Il27ra on transferred T cells resulted in diminished weight loss and reduced colonic inflammation. A greater fraction of transferred T cells assumed a Foxp3+ phenotype in the absence of Il27ra, suggesting that IL-27 functions to restrain regulatory T cell (Treg) development. Indeed, IL-27 suppressed Foxp3 induction in vitro and in an ovalbumin-dependent tolerization model in vivo. Furthermore, effector cell proliferation and IFN-γ production were reduced in the absence of Il27ra. Collectively, we describe a proinflammatory role of IL-27 in T cell–dependent intestinal inflammation and provide a rationale for targeting this cytokine in pathological situations that result from a breakdown in peripheral immune tolerance.


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