Our findings reveal altered perivascular inflammatory cell infiltration in pulmonary vascular lesions of patients with idiopathic pulmonary arterial hypertension. Targeting attraction of inflammatory cells by blocking stromal-derived factor-1 may be a novel approach for treatment of PAH.

Spiegelmers are synthetic target-binding oligonucleotides built from non-natural l-nucleotides. Like aptamers, Spiegelmers fold into distinct shapes that bind the targets with high affinity and selectivity. Furthermore, the mirror-image configuration confers plasma stability and immunological passivity. Various Spiegelmers against pharmacologically attractive targets were shown to be efficacious in animal models. Three Spiegelmer candidates: emapticap pegol (NOX-E36; anti-CCL2), olaptesed pegol (NOX-A12; anti-CXCL12) and lexaptepid pegol (NOX-H94; anti-hepcidin), underwent regulatory safety studies, demonstrated good safety profiles in healthy volunteers and were taken into Phase IIa studies in patients. Proof-of-concept for emapticap pegol has recently been demonstrated in diabetic nephropathy patients. Furthermore, promising interim Phase IIa data of olaptesed pegol and lexapteptid pegol also suggest efficacy in the respective patient populations.

Disruption of the programmed cell death protein 1 (PD-1) pathway with immune checkpoint inhibitors represents a major breakthrough in the treatment of non-small cell lung cancer. We hypothesized that combined inhibition of C5a/C5aR1 and PD-1 signaling may have a synergistic antitumor effect. The RMP1-14 antibody was used to block PD-1, and an L-aptamer was used to inhibit signaling of complement C5a with its receptors. Using syngeneic models of lung cancer, we demonstrate that the combination of C5a and PD-1 blockade markedly reduces tumor growth and metastasis and leads to prolonged survival. This effect is accompanied by a negative association between the frequency of CD8 T cells and myeloid-derived suppressor cells within tumors, which may result in a more complete reversal of CD8 T-cell exhaustion. Our study provides support for the clinical evaluation of anti-PD-1 and anti-C5a drugs as a novel combination therapeutic strategy for lung cancer. Using a variety of preclinical models of lung cancer, we demonstrate that the blockade of C5a results in a substantial improvement in the efficacy of anti-PD-1 antibodies against lung cancer growth and metastasis. This study provides the preclinical rationale for the combined blockade of PD-1/PD-L1 and C5a to restore antitumor immune responses, inhibit tumor cell growth, and improve outcomes of patients with lung cancer. .

Increased microvascular dilatation and permeability is observed during allograft rejection. Because vascular integrity is an important indicator of transplant health, we have sought to limit injury to blood vessels by blocking complement activation. Although complement component 3 (C3) inhibition is known to be vasculoprotective in transplantation studies, we recently demonstrated the paradoxical finding that, early in rejection, C3 −/− transplant recipients actually exhibit worse microvascular injury than controls. In the genetic absence of C3, thrombin-mediated complement component 5 (C5) convertase activity leads to the generation of C5a (anaphylatoxin), a promoter of vasodilatation and permeability. In the current study, we demonstrated that microvessel thrombin deposition is significantly increased in C3 −/− recipients during acute rejection. Thrombin colocalization with microvessels is closely associated with remarkably elevated plasma levels of C5a, vasodilatation, and increased vascular permeability. Administration of NOX-D19, a specific C5a inhibitor, to C3 −/− recipients of airway transplants significantly improved tissue oxygenation, limited microvascular leakiness, and prevented airway ischemia, even in the absence of conventional T-cell–directed immunosuppression. As C3 inhibitors enter the clinics, the simultaneous targeting of this thrombin-mediated complement activation pathway and/or C5a itself may confer significant clinical benefit.

Heat sensitivity shows considerable functional variability in humans and laboratory animals, and is fundamental to inflammatory and possibly neuropathic pain. In the mouse, at least, much of this variability is genetic because inbred strains differ robustly in their behavioral sensitivity to noxious heat. These strain differences are shown here to reflect differential responsiveness of primary afferent thermal nociceptors to heat stimuli. We further present convergent behavioral and electrophysiological evidence that the variable responses to noxious heat are due to strain-dependence of CGRP expression and sensitivity. Strain differences in behavioral response to noxious heat could be abolished by peripheral injection of CGRP, blockade of cutaneous and spinal CGRP receptors, or long-term inactivation of CGRP with a CGRP-binding Spiegelmer. Linkage mapping supports the contention that the genetic variant determining variable heat pain sensitivity across mouse strains affects the expression of the Calca gene that codes for CGRP␣.calcitonin gene-related peptide ͉ genetic ͉ Calca ͉ nociceptors ͉ pain H umans display wide individual variability in sensitivity to pain.Although the relative importance of genes versus experience in human pain perception is unclear, recent studies have shown that mouse strains display large differences in behavioral pain sensitivity that are heritable (1). These same studies revealed genetic correlations between baseline thermal nociception and the hypersensitivity states associated with inflammatory and neuropathic pain (2). Of the strains examined, AKR and C57BL͞6 mice displayed the largest and most consistent differences in several different assays of thermal nociception, with AKR being much less sensitive than C57BL͞6. In contrast, AKR mice exhibit more robust heat hyperalgesia after inflammatory or nerve injury (1). Despite our considerable knowledge of the behavioral ''phenomics'' of baseline heat pain and hyperalgesia, there are almost no published data regarding the underlying cellular or molecular mechanisms. Here we show that the observed strain differences in response to thermal stimulation are caused by corresponding differences in the functioning of primary afferent nociceptors. The differences in nociceptor sensitivity, in turn, are caused by the presence of and sensitivity to the neuropeptide calcitonin gene-related polypeptide (CGRP). Finally, linkage mapping revealed a candidate gene likely responsible for the strain difference: Calca, the gene encoding CGRP␣.CGRP␣ is a secretory neuropeptide released from thin nerve fibers at their peripheral and central terminals, which is thought to contribute importantly to neurogenic inflammation in the skin and to central sensitization in the spinal cord (3-6). CGRP acts through a G s protein-coupled receptor complex to activate cAMPdependent protein kinase (PKA). PKA, via the transcription factor cAMP response element-binding protein, enhances expression of pronociceptive genes including the Calca gene itself (7-9). Moreover, many...

SUMMARY Bone marrow (BM) metastasis remains one of the main causes of death associated with solid tumors as well as with Multiple Myeloma (MM). Targeting the BM niche to prevent or modulate metastasis has not been successful to date. Here we show that stromal cell derived factor-1 (SDF-1/CXCL12) is highly expressed in active MM, as well as in BM sites of tumor metastasis, and report on the discovery of the high affinity anti-SDF-1 PEGylated mirror-image l-oligonucleotide (olaptesed-pegol). In vivo confocal imaging showed that SDF-1 levels are increased within MM cell-colonized BM areas. Using in vivo murine and xenograft mouse models, we document that in vivo SDF-1 neutralization within BM niches leads to a microenvironment that is less receptive for MM cells and reduces MM cell homing and growth, thereby inhibiting MM disease progression. Targeting of SDF-1 represents a valid strategy for preventing or disrupting colonization of the BM by MM cells.

We observed that sphingosine-1-phosphate (S1P) and ceramide-1-phosphate (C1P) strongly enhance in vitro motility and adhesion of human rhabdomyosarcoma (RMS) cells. This effect was observed at physiological concentrations of both bioactive lipids, which are present in biological fluids, and is much stronger than the effects observed in response to known RMS pro-metastatic factors such as stromal derived factors-1 (SDF-1) or hepatocyte growth factor/scatter factor (HGF/SF). We also present novel evidence that the levels of S1P and C1P increase in several organs after γ-irradiation or chemotherapy, which indicates induction of an unwanted pro-metastatic environment related to treatment. Most importantly, we found that the metastasis of RMS cells in response to S1P can be effectively inhibited in vivo with the S1P-specific binder NOX-S93 that is based on a high affinity Spiegelmer. We propose that bioactive lipids play a previously underappreciated role in dissemination of RMS and the unwanted side effects of radio/chemotherapy by creating a pro-metastatic microenvironment. Therefore, an anti-metastatic treatment with specific S1P-binding scavenger such as NOX-S93 could become a part of standard radio/chemotherapy.

We developed an integrated method to identify aptamers with only 10 fixed nucleotides through ligation and removal of primer binding sites within the systematic evolution of ligands by exponential enrichment (SELEX) process. This Tailored-SELEX approach was validated by identifying a Spiegelmer ('mirror-image aptamer') that inhibits the action of the migraine-associated target calcitonin gene-related peptide 1 (alpha-CGRP) with an IC50 of 3 nM at 37 degrees C in cell culture. Aptamers are oligonucleotide ligands that can be generated to bind to targets with high affinity and specificity. Stabilized aptamers and Spiegelmers have shown activity in vivo and may be used as therapeutics. Aptamers are isolated by in vitro selection from combinatorial nucleic acid libraries that are composed of a central randomized region and additional fixed primer binding sites with approximately 30-40 nt. The identified sequences are usually not short enough for efficient chemical Spiegelmer synthesis, post-SELEX stabilization of aptamers and economical production. If the terminal primer binding sites are part of the target recognizing domain, truncation of aptamers has proven difficult and laborious. Tailored-SELEX results in short sequences that can be tested more rapidly in biological systems. Currently, our identified CGRP binding Spiegelmer serves as a lead compound for in vivo studies.