Blocking the CC chemokine receptor 5 pathway by antisense peptide nucleic acid prolongs islet allograft survival

The commonness in immune infiltration of rheumatoid arthritis and atherosclerosis: Screening for central targets via microarray data analysis

Background

Although increasing evidence has reported an increased risk of atherosclerosis (AS) in rheumatoid arthritis (RA), the communal molecular mechanism of this phenomenon is still far from being fully elucidated. Hence, this article aimed to explore the pathogenesis of RA complicated with AS.

Methods

Based on the strict inclusion/exclusion criteria, four gene datasets were downloaded from the Gene Expression Omnibus (GEO) database. After identifying the communal differentially expressed genes (DEGs) and hub genes, comprehensive bioinformatics analysis, including functional annotation, co-expression analysis, expression validation, drug-gene prediction, and TF-mRNA-miRNA regulatory network construction, was conducted. Moreover, the immune infiltration of RA and AS was analyzed and compared based on the CIBERSORT algorithm, and the correlation between hub genes and infiltrating immune cells was evaluated in RA and AS respectively.

Results

A total of 54 upregulated and 12 downregulated communal DEGs were screened between GSE100927 and GSE55457, and functional analysis of these genes indicated that the potential pathogenesis lies in immune terms. After the protein-protein interaction (PPI) network construction, a total of six hub genes (CCR5, CCR7, IL7R, PTPRC, CD2, and CD3D) were determined as hub genes, and the subsequent comprehensive bioinformatics analysis of the hub genes re-emphasized the importance of the immune system in RA and AS. Additionally, three overlapping infiltrating immune cells were found between RA and AS based on the CIBERSORT algorithm, including upregulated memory B cells, follicular helper T cells and γδT cells.

Conclusions

Our study uncover the communal central genes and commonness in immune infiltration between RA and AS, and the analysis of six hub genes and three immune cells profile might provide new insights into potential pathogenesis therapeutic direction of RA complicated with AS.

Targeted antisense radiotherapy and dose fractionation using a (177)Lu-labeled anti-bcl-2 peptide nucleic acid-peptide conjugate

INTRODUCTION

The overall goal of these studies was to test the hypothesis that simultaneous down-regulation of a tumor survival gene and delivery of internally emitted cytotoxic radiation will be more effective than either treatment modality alone. The objectives were to evaluate the therapeutic efficacy of a (177)Lu-labeled anti-bcl-2-PNA-Tyr(3)-octreotate antisense conjugate in a mouse model bearing human non-Hodgkin's lymphoma (NHL) tumor xenografts and to optimize targeted antisense radiotherapy by dose fractionation.

METHODS

In the initial therapy studies, tumor-bearing mice were given saline, nonradioactive DOTA-anti-bcl-2-PNA-Tyr(3)-octreotate, (177)Lu-DOTA-Tyr(3)-octreotate, (177)Lu-DOTA-PNA-peptide alone, or (177)Lu-DOTA-PNA-peptide followed by a chase dose of nonradioactive PNA-peptide. The MTD of (177)Lu-DOTA-anti-bcl-2-PNA-Tyr(3)-octreotate was then determined. Subsequently single dose MTD and four weekly fractionated doses were directly compared, followed by histopathologic evaluation.

RESULTS

Antisense radiotherapy using 4.44 MBq of the (177)Lu-DOTA-PNA-peptide followed by nonradioactive PNA-peptide was significantly more effective than other low dose treatment regimens. A dose of 18.5 MBq of (177)Lu-DOTA-PNA-peptide was determined to be the approximate maximum tolerated dose (MTD). The median times to progression to a 1cm(3) tumor volume were 32 and 49 days for single dose MTD and fractionated dose (4 × 4.63 MBq) groups, respectively. Histopathology revealed metastases in the single dose groups, but not in the dose fractionation group.

CONCLUSIONS

Targeted antisense radiotherapy using (177)Lu-DOTA-anti-bcl-2-PNA-Tyr(3)-octreotate and DOTA-PNA-peptide conjugate effectively inhibited tumor progression in a mouse model of NHL. Furthermore, a dose fractionation regimen had a significant advantage over a single high dose, in terms of tumor growth inhibition and prevention of metastasis.

ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE

Down-regulating bcl-2, an anti-apoptotic proto-oncogene, is a mechanism to reverse chemotherapy resistance or failure in humans with NHL. We have developed a (177)Lu-DOTA-anti-bcl-2-PNA-Tyr(3)-octreotate conjugate for targeted antisense radiotherapy, in which down-regulation of bcl-2 and delivery of cytotoxic radiation occur simultaneously. Our previous studies have shown highly specific inhibition of bcl-2 protein, additive in vitro cytotoxic effects on human lymphoma cells, and favorable biodistribution and dosimetric properties. Lutetium-177 targeted antisense radiotherapy demonstrates a significant advantage over conventional (177)Lu-peptide receptor radionuclide therapy in a mouse model of NHL. Our preclinical studies identified an effective combination of antisense and radionuclide therapy, with the goal of future clinical trials in patients.

Mechanisms and mediators of inflammation: potential models for skin rejection and targeted therapy in vascularized composite allotransplantation

Vascularized composite allotransplantation (VCA) is an effective treatment option for patients suffering from limb loss or severe disfigurement. However, postoperative courses of VCA recipients have been complicated by skin rejection, and long-term immunosuppression remains a necessity for allograft survival. To widen the scope of this quality-of-life improving procedure minimization of immunosuppression in order to limit risks and side effects is needed. In some aspects, the molecular mechanisms and dynamics of skin allograft rejection seem similar to inflammatory skin conditions. T cells are key players in skin rejection and are recruited to the skin via activation of adhesion molecules, cytokines, and chemokines. Blocking these molecules has not only shown success in the treatment of inflammatory dermatoses, but also prolonged graft survival in various models of solid organ transplantation. In addition to T cell recruitment, ectopic lymphoid structures within the allograft associated with chronic rejection in solid organ transplantation might contribute to the strong alloimmune response towards the skin. Selectively targeting the molecules involved offers exciting novel therapeutic options in the prevention and treatment of skin rejection after VCA.

Dual targeting of CCR2 and CCR5: therapeutic potential for immunologic and cardiovascular diseases

A cardinal feature of inflammation is the tissue recruitment of leukocytes, a process that is mediated predominantly by chemokines via their receptors on migrating cells. CCR2 and CCR5, two CC chemokine receptors, are important players in the trafficking of monocytes/macrophages and in the functions of other cell types relevant to disease pathogenesis. This review provides a brief overview of the biological actions of CCR2 and CCR5 and a comprehensive summary of published data that demonstrate the involvement of both receptors in the pathogenesis of immunologic diseases (RA, CD, and transplant rejection) and cardiovascular diseases (atherosclerosis and AIH). In light of the potential for functional redundancy of chemokine receptors in mediating leukocyte trafficking and the consequent concern over insufficient efficacy offered by pharmacologically inhibiting one receptor, this review presents evidence supporting dual targeting of CCR2 and CCR5 as a more efficacious strategy than targeting either receptor alone. It also examines potential safety issues associated with such dual targeting.

Innate immunity and heat shock response in islet transplantation

Islet transplantation is an extremely effective therapy for patients with type I diabetes, providing tight control of blood glucose and persistent insulin release. Islet grafts struggle with various stress responses and immunity attacks, which contribute to loss of islet grafts in the long term. In this review we focus upon the innate immunity and heat shock responses, which are closely relevant to the outcome of islet grafts. Potential strategies provided by more comprehensive interventions to control innate immunity and by selective induction of heat shock proteins may ameliorate the outcome of islet transplantation.

New peptide nucleic acid analogues: synthesis and applications

Peptide nucleic acids are oligonucleotide mimics characterised by high chemical and enzymatic stability, high specificity and affinity toward complementary DNA/RNA. The lack of charge and polar groups in the backbone decrease their solubility in aqueous environment and their ability to cross cell membranes, reducing their performance in in vivo applications. To improve solubility, increase affinity and specificity of binding and to control recognition between nucleic acids, several analogues bearing modifications on the nucleobase, nucleobase-backbone linker and on the backbone were synthesised. This paper describes the synthesis and applications of Peptide nucleic acid analogues and discusses the potential of analogues for which no application is reported.