Cellular therapy: Immune‐related complications

The advent of chimeric antigen receptor T (CAR‐T) and the burgeoning field of cellular therapy has revolutionized the treatment of relapsed/refractory leukemia and lymphoma. This personalized “living therapy” is highly effective against a number of malignancies, but this efficacy is tempered by side effects relatively unique to immunotherapies, including CAR‐T. The overwhelming release of cytokines and chemokines by activated CAR‐T and other secondarily activated immune effector cells can lead to cytokine release syndrome (CRS), which can have clinical and pathophysiology similarities to systemic inflammatory response syndrome and macrophage activating syndrome/hemophagocytic lymphohistiocytosis. Tocilizumab, an anti‐IL6 receptor antibody, was recently FDA approved for treatment of CRS after CAR‐T based on its ability to mitigate CRS in many patients. Unfortunately, some patients are refractory and additional therapies are needed. Patients treated with CAR‐T can also develop neurotoxicity and, as the biology is poorly understood, current therapeutic interventions are limited to supportive care. Nevertheless, a number of recent studies have shed new light on the pathophysiology of CAR‐T‐related neurotoxicity, which will hopefully lead to effective treatments. In this review we discuss some of the mechanistic contributions intrinsic to the CAR‐T construct, the tumor being treated, and the individual patient that impact the development and severity of CRS and neurotoxicity. As CAR‐T and cellular therapy have redefined the concept of personalized medicine, so too will personalization be necessary in managing the unique side effects of these therapies.     

Immune‐ and Ribosome‐Related Genes were Associated with Systemic Vasculitis

This study aimed to investigate the molecular mechanism of systemic vasculitis via bioinformatics analysis. Gene express profile of E‐GEOD‐16945 (13 Takayasu arteritis samples and 13 control samples) was downloaded from European Bioinformatics Institute (EBI) database. Differentially expressed genes (DEGs) were screened between Takayasu arteritis and normal controls (|log FC| > 1). Basic local alignment search tool (BLASTX) was used for the Clusters of Orthologous Groups (COG) classification of DEGs. Gene ontology analysis was performed for the DEGs (P < 0.05). A gene expression network was built with DEGs. Mcode in Cytoscape software was used to extract modules from the network (degree ≥ 2, K‐core ≥ 2 and adjusted P‐value < 0.05) followed by pathway analysis using GenMAPP (false discovery rate < 0.05). A total of 747 DEGs were identified. There were 16 significant GO function terms enriched with DEGs, of which immune and defence response was the most significant GO term. Totally, three modules were extracted from gene expression network, including one module constituted with upregulated genes and two modules constituted with downregulated genes. Furthermore, human leucocyte antigen (HLA)‐DRB1, HLA‐DPA1, HLA‐DPB1, HLA‐DOA and HLA‐DRA in the downregulated modules were significantly linked to immune‐related pathways (intestinal immune network for IgA production and systemic lupus erythematosus pathways), while ribosomal protein L 31 (RPL31), RPS3A and RPL9 in the upregulated module were enriched in ribosome pathway. The immune‐related pathways, ribosome pathway, immune‐related genes including (HLA‐DRB1, HLA‐DPA1, HLA‐DPB1, HLA‐DOA and HLA‐DRA) and ribosome‐related genes (RPL31, RPS3A and RPL9) might be involved in systemic vasculitis.     

Immune‐mediated diseases and microbial exposure in early life

The non‐communicable disease pandemic includes immune‐mediated diseases such as asthma and allergy, which are likely originating in early life where the immature immune system is prone to alterations caused by the exposome. The timing of exposure seems critical for the developing immune system, and certain exposures may have detrimental effects in the earliest life, but no or even beneficial effects later. The human microbiome and infections are candidates as intermediary in the interaction between the host and the environment. The evidence seems inconsistent as infections as well as particular colonization patterns in neonates drive both short‐term and long‐term asthma symptoms, while, on the other hand, the composition of the microbiome in early life may protect against asthma and allergy in later life. This apparent contradiction may be explained by a deeper disease heterogeneity than we are currently able to discriminate, and in particular, the indiscriminate lumping together of different diseases into one atopic disease category. Also, the microbiome needs a differentiated understanding, considering balance between microbial groups, diversity and microbial genetic capability. Furthermore, the effects of the microbial exposure may only affect individuals with certain susceptibility genes. Few of the observations have been replicated, and publication bias is likely. Therefore, we are still far from understanding, or having proved, causal effects of the human microbiome. Still, the microbiome–gene interaction is a fascinating paradigm that fosters exiting research and promises a breakthrough in the understanding of the mechanisms driving asthma, allergy and eczema, and potentially also other immune‐mediated non‐communicable diseases.     

Nitroxide‐Mediated Radical Polymerization of N‐tert‐Butylacrylamide

The nitroxide‐mediated polymerization of N‐tert‐butylacrylamide (TBAM) in DMF at 120 °C using SG1/DEPN and AIBN has been investigated. Linear growth in number‐average molecular weight ( ) versus conversion and narrow molecular weight distributions (MWDs) with high livingness were obtained up to ≈8 000 g · mol^?1. For higher molecular weights, the MWDs gradually became broader with low molecular weight tailing, and deviated downwards from theoretical values. Quantitative analyses of MWDs, along with specifically designed conventional radical polymerizations at 120 °C, were consistent with chain transfer to monomer limiting the attainable . This finding can be equally applied to existing literature polymerizations of TBAM.

     

Xanthate‐Mediated Controlled Radical Polymerization of N‐Vinylcarbazole

Summary: Well‐defined poly(N‐vinylcarbazole) [poly(NVC)] was synthesized by macromolecular design via interchange of the xanthates (MADIX)/reversible addition‐fragmentation chain transfer (RAFT) polymerization. The homopolymers with controlled molecular weights ( = 3 000–48 000) and low polydispersities indices ( = 1.15–1.20) were obtained by the polymerization of NVC with AIBN in the presence of O‐ethyl‐S‐(1‐phenylethyl) dithiocarbonate as a xanthate‐type chain transfer agent (CTA). Good control of the polymerization was confirmed by the linear first‐order kinetic plot, the molecular weight controlled by the monomer/CTA molar ratio, linear increase in the molecular weight with the conversion, and the ability to extend the chains by the second addition of the monomer.

Radical polymerization of NVC in the presence of CTA and plot of number‐average molecular weight (circles) and polydispersity (squares) as a function of conversion.     

Immune‐monitoring in Kawasaki disease patients treated with infliximab and intravenous immunoglobulin

The expansion of regulatory T cells (T_reg) controls inflammation in children with acute Kawasaki disease (KD). Blockade of tumour necrosis factor (TNF)-α is an emerging therapy for KD patients with refractory inflammation, but there is concern that this therapy could impede the host immune regulation. To define the effect of TNF-α blockade, we conducted ex-vivo immune-monitoring in KD subjects who participated in a randomized, double-blind, placebo-controlled clinical trial of the addition of infliximab to standard intravenous immunoglobulin (IVIG) therapy. We enumerated circulating myeloid and plasmocytoid dendritic cells (DC), regulatory T cells (T_reg) and memory T cells (T_mem) in 14 consecutive, unselected KD patients (seven treated with IVIG, seven with IVIG + infliximab) at three time-points: (i) acute phase prior to treatment, (ii) subacute phase and (iii) convalescent phase. Myeloid DC (mDC), but not plasmacytoid DC (pDC), were numerous in the peripheral blood in acute KD subjects and decreased in the subacute phase in both IVIG⁻ and IVIG ⁺ infliximab-treated groups. The co-stimulatory molecule for antigen presentation to T cells and CD86 decreased in mDC from acute to subacute time-points in both treatment groups, but not in the single patient who developed coronary artery aneurysms. We also defined tolerogenic mDC that expand in the subacute phase of KD not impaired by infliximab treatment. T_reg and T_mem expanded after treatment with no significant differences between the two groups. Treatment of KD patients with infliximab does not adversely affect generation of tolerogenic mDC or the development of T cell regulation and memory.     

N‐Hydroxyphthalimide‐Mediated Oxidation of Styrene by Molecular Oxygen

In this work, the N‐hydroxyphthalimide (NHPI) is used for the oxidative polymerization of styrene at 25–100 psi oxygen pressure at 35–55 °C to obtain a faster rate of polymerization than in 2,2′‐azobisisobutyronitrile (AIBN)‐initiated polymerizations. The rates for oxidative polymerization are determined from the oxygen consumption (Δp) against time plots and NHPI shows a reaction rate increased several fold compared with AIBN. The kinetics of the oxidative polymerization reactions are studied at various concentrations of oxygen, NHPI, AIBN, and monomer. The polymerization rate of styrene is almost the same when the NHPI analogue, N‐hydroxysuccinimide (NHSI), is employed. A mechanism of oxidative polymerization in the presence of NHPI is suggested on the basis of the kinetic data and characterization results of poly(styrene peroxide) (PSP). The NHPI is efficient in initiation of the oxidative radical polymerization of styrene.

     

Hydrogen Abstraction Followed by Nitroxide‐Mediated Polymerization: Synthesis of 2,7‐Dibromofluorene‐Labeled Polystyrene

Chromophore end‐labeled polystyrene is synthesized using nitroxide‐mediated polymerization (NMP) by decomposing 2‐2′‐azoisobutyronitrile (AIBN) or benzoyl peroxide (BPO) in the presence of fluorene or fluorene derivatives. End‐labeling is dependent on the thermally produced radical species selectively abstracting a hydrogen atom from the 9‐position of the fluorene species prior to initiation of styrene. From gel permeation chromatography (GPC) data and UV–Vis analysis, it is found that AIBN initiation, compared to BPO, leads to a more controlled polymerization system, producing polymers with predictable molecular weights, narrower polydispersity index (PDI) values (<1.3), and higher amounts of fluorene end‐labeling. In terms of the reaction parameters, no consistent trend is observed as a function of the timing of styrene's addition or the temperature at which the hydrogen abstraction phase is performed. Analysis of the chromophore content by UV–Vis spectroscopy demonstrated that the presence of bromine atoms on the 2‐ and 7‐position of the fluorene species leads to higher percent labeling of the chromophore species, presumably due to a more facile abstraction of the hydrogen at the 9‐position.     

The Role of MicroRNAs in Autoimmune Diseases with Skin Involvement

MicroRNAs (miRNAs) are small non‐coding RNA molecules that negatively modulate gene expression by binding to the 3′ untranslated region (UTR) of target messenger RNAs (mRNAs), which leads to the degradation or translational repression of their target mRNAs. Previous research on miRNAs has revealed a new paradigm of gene regulations and pathways involved in the pathogenesis of autoimmune disorders and malignant diseases. The roles of miRNAs in cellular processes, including cell differentiation, proliferation, apoptosis and immune functions, are not clearly understood. MiRNAs are easily detected in a variety of sources, including tissues, serum and other body fluids, and this make them a good biological sample for pathogenic studies and disease biomarker development. This review encompasses the current understanding of the roles of miRNAs in autoimmunity and the cellular and molecular mechanisms of miRNAs in various autoimmune diseases (AIMDs). Specifically, we focus on the target genes of miRNAs and the biological processes associated with autoimmune diseases with skin involvement, including systemic lupus erythematosus, psoriasis, systemic sclerosis, Behcet's disease and dermatomyositis. In addition, the diagnostic and therapeutic relevance of miRNAs that are involved in autoimmunity are elucidated to provide information for clinical implications.     

Kinetics of Dithiobenzoate‐Mediated Methyl Methacrylate Polymerization

The equilibrium constant, K_eq, of the reversible addition–fragmentation chain transfer (RAFT) model system methyl methacryl dithiobenzoate (MMADB) and of methyl methacrylate (MMA) polymerization mediated by MMADB is studied via electron paramagnetic resonance (EPR) spectroscopy in the range 70 to 110 °C and at ?40 °C, respectively. The measured difference in activation energy of the addition and fragmentation steps is: E_a(k_ad) – E_a(k_frag) ≈ ?36.6 kJ mol^?1. Significant amounts of “missing step” products from reaction of the cross‐termination product with a methyl methacrylyl radical are found. The fast “missing step” reaction and low K_eq, due to slow k_ad, are responsible for rate retardation being absent in dithiobenzoate‐mediated MMA polymerization.

     

Anti‐tumour immune response in GL261 glioblastoma generated by Temozolomide Immune‐Enhancing Metronomic Schedule monitored with MRSI‐based nosological images

Glioblastomas (GB) are brain tumours with poor prognosis even after aggressive therapy. Improvements in both therapeutic and follow‐up strategies are urgently needed. In previous work we described an oscillatory pattern of response to Temozolomide (TMZ) using a standard administration protocol, detected through MRSI‐based machine learning approaches. In the present work, we have introduced the Immune‐Enhancing Metronomic Schedule (IMS) with an every 6‐d TMZ administration at 60 mg/kg and investigated the consistence of such oscillatory behaviour. A total of n = 17 GL261 GB tumour‐bearing C57BL/6j mice were studied with MRI/MRSI every 2 d, and the oscillatory behaviour (6.2 ± 1.5 d period from the TMZ administration day) was confirmed during response. Furthermore, IMS‐TMZ produced significant improvement in mice survival (22.5 ± 3.0 d for controls vs 135.8 ± 78.2 for TMZ‐treated), outperforming standard TMZ treatment. Histopathological correlation was investigated in selected tumour samples (n = 6) analyzing control and responding fields. Significant differences were found for CD3+ cells (lymphocytes, 3.3 ± 2.5 vs 4.8 ± 2.9, respectively) and Iba‐1 immunostained area (microglia/macrophages, 16.8% ± 9.7% and 21.9% ± 11.4%, respectively). Unexpectedly, during IMS‐TMZ treatment, tumours from some mice (n = 6) fully regressed and remained undetectable without further treatment for 1 mo. These animals were considered “cured” and a GL261 re‐challenge experiment performed, with no tumour reappearance in five out of six cases. Heterogeneous therapy response outcomes were detected in tumour‐bearing mice, and a selected group was investigated (n = 3 non‐responders, n = 6 relapsing tumours, n = 3 controls). PD‐L1 content was found ca. 3‐fold increased in the relapsing group when comparing with control and non‐responding groups, suggesting that increased lymphocyte inhibition could be associated to IMS‐TMZ failure. Overall, data suggest that host immune response has a relevant role in therapy response/escape in GL261 tumours under IMS‐TMZ therapy. This is associated to changes in the metabolomics pattern, oscillating every 6 d, in agreement with immune cycle length, which is being sampled by MRSI‐derived nosological images.     

Organometallic‐Mediated Radical Polymerization: Developing Well‐Defined Complexes for Reversible Transition Metal‐Alkyl Bond Homolysis

Organometallic‐mediated radical polymerization (OMRP) has emerged as a powerful new class of living controlled radical polymerization. In order to fulfill its potential in the polymerization of vinyl acetate (VOAc) and other challenging monomers, the effects of ancillary ligands on the metal‐alkyl bond dissociation energy in OMRP reagents must be thoroughly explored. Recent results investigating structure‐activity relationships in well‐defined cobalt, iron and chromium complexes will be discussed. The involvement of radical intermediates in oxidative addition of secondary alkyls for catalytic cross‐coupling reactions catalyzed by first row transition metals will also be examined for relevant design concepts.

     

PEG‐Based Microgels Formed by Visible‐Light‐Mediated Thiol‐Ene Photo‐Click Reactions

Step‐growth PEG‐based microgels are produced via three liquid–liquid two‐phase suspension polymerization systems: i) hexane with surfactants Span80/Tween80; ii) mineral oil with surfactant Pluronic F‐68; and iii) surfactant‐free dextran‐rich aqueous solution. Following short vortexing to create monomer droplets, microgels are polymerized by a visible‐light‐initiated thiol‐ene photo‐click reaction using eosin‐Y as the only photoinitiator. The use of hexane as the organic phase and Span‐80/Tween‐80 as the surfactants leads to PEG microgels with entrapped solvent droplets that dissolve rapidly with time. Microgels polymerized in mineral oil with surfactant Pluronic F‐68 contain no entrapped droplets and are more uniform with smaller sizes. Visible‐light‐cured step‐growth thiol‐ene microgels can also be photo­polymerized in a surfactant‐free aqueous two‐phase system. The sizes of the microgels formed in aqueous phase are one order of magnitude smaller than those formed in organic solvent. Dual‐layer microgels are also prepared using two‐step thiol‐ene reactions.