Oncolytic therapy with recombinant vaccinia viruses targeting the interleukin-15 pathway elicits a synergistic response

We developed recombinant variants of oncolytic vaccinia virus LIVP strain expressing interleukin-15 (IL-15) or its receptor subunit alpha (IL-15Rα) to stimulate IL-15-dependent immune cells. We evaluated their oncolytic activity either alone or in combination with each other in vitro and in vivo using the murine CT26 colon carcinoma and 4T1 breast carcinoma models. We demonstrated that the admixture of these recombinant variants could promote the generation of the IL-15/IL-15Rα complex. In vitro studies indicated that 4T1 breast cancer cells were more susceptible to the developed recombinant viruses. In vivo studies showed significant survival benefits and tumor regression in 4T1 breast cancer syngeneic mice that received a combination of LIVP-IL15-RFP with LIVP-IL15Ra-RFP. Histological analysis showed recruited lymphocytes at the tumor region, while no harmful effects to the liver or spleen of the animals were detected. Evaluating tumor-infiltrated lymphocytes represented profound activation of cytotoxic T cells and macrophages in mice receiving combination therapy. Thus, our experiments showed superior oncolytic effectiveness of simultaneous injection of LIVP-IL15-RFP and LIVP-IL15Ra-RFP in breast cancer-bearing mice. The combined therapy by these recombinant variants represents a potent and versatile approach for developing new immunotherapies for breast cancer.

[Injected non-absorbable fillers in large volumes]

AIM

To present treatment strategy for large volumes of injectable non-absorbable 'shell-less' soft tissue fillers (vaseline, synthol, silicone etc.).

MATERIAL AND METHODS

The authors present an experience of surgical treatment of 8 patients who underwent injections of medical vaseline (breast augmentation, n=5) and synthol (muscles enlargement, n=3) and review of the current literature devoted to this problem.

RESULTS

Injection of large amounts (over 50 ml) of non-absorbable fillers into soft tissues is unacceptable and leads to numerous complications. Oil-based 'shell-less' fillers cannot be removed by minimally invasive techniques (puncture, mini-incisions, etc.) due to multiple diffuse lesions in the form of oleogranulomas (cysts of different size) and surrounding widespread inflammation and fibrosis of tissues. Surgery is the only adequate method. However, this approach is followed by scars and often tissue contour deformation. Migration of these fillers to other anatomical areas (from the neck to the lower extremities) significantly complicates the situation, treatment and results. In case of categorical refusal of patients from surgical treatment and no complaints, they should be properly informed about possible consequences and complications and dynamic medical supervision is necessary. Intraoperative ultrasound examination is useful for the control of radical removal of pathological areas. Timely removal of non-absorbable fillers allows to avoid serious complications and to achieve good aesthetic results.

Development of a motor and somatosensory evoked potentials-guided spinal cord Injury model in non-human primates

Background Nonhuman primates (NHP) may provide the most adequate (in terms of neuroanatomy and neurophysiology) model of spinal cord injury (SCI) for testing regenerative therapies, but bioethical considerations exclude their use in severe SCI. New Method A reproducible model of SCI at the lower thoracic level has been developed in Rhesus macaques. The model comprises surgical resection of 25% of the spinal cord in the projection of the dorsal funiculus and dorsolateral corticospinal pathways, controlled via registration of intraoperative evoked potentials (EPs). The animals were evaluated using the modified Hindlimb score, MRI, SSEP, and MEP over a time period of 8-12 weeks post-SCI, followed by histological examination. Results Complete disappearance of intraoperative EPs from distal hindlimb muscles without restoration within two weeks post-SCI was an indicator for irreversible disruption of the abovementioned pathways. As a result, controlled damage to the spinal cord was achieved in three NHPs, clinically manifested as irreversible lower monoplegia. No significant functional restoration was observed in these NHPs up to 12 weeks post-SCI. Demyelination of the damaged ascending tracts was detected. Disturbances in pelvic organ function were not observed in all animals. Comparison with existing methods The new method of EPs-guided SCI allows a more controlled and irreversible damage to the spinal cord compared with contusion and other transection approaches. Conclusions This method to induce complete SCI in NHP is well tolerated, reproducible and ethically acceptable: these are valuable attributes in a preclinical model that will hopefully help advance testing of new regenerative therapies in SCI.

Urokinase-type plasminogen activator (uPA) is critical for progression of tuberous sclerosis complex 2 (TSC2)-deficient tumors

Lymphangioleiomyomatosis (LAM) is a fatal lung disease associated with germline or somatic inactivating mutations in tuberous sclerosis complex genes (TSC1 or TSC2). LAM is characterized by neoplastic growth of smooth muscle-α-actin-positive cells that destroy lung parenchyma and by the formation of benign renal neoplasms called angiolipomas. The mammalian target of rapamycin complex 1 (mTORC1) inhibitor rapamycin slows progression of these diseases but is not curative and associated with notable toxicity at clinically effective doses, highlighting the need for better understanding LAM's molecular etiology. We report here that LAM lesions and angiomyolipomas overexpress urokinase-type plasminogen activator (uPA). Tsc1^-/- and Tsc2^-/- mouse embryonic fibroblasts expressed higher uPA levels than their WT counterparts, resulting from the TSC inactivation. Inhibition of uPA expression in Tsc2-null cells reduced the growth and invasiveness and increased susceptibility to apoptosis. However, rapamycin further increased uPA expression in TSC2-null tumor cells and immortalized TSC2-null angiomyolipoma cells, but not in cells with intact TSC. Induction of glucocorticoid receptor signaling or forkhead box (FOXO) 1/3 inhibition abolished the rapamycin-induced uPA expression in TSC-compromised cells. Moreover, rapamycin-enhanced migration of TSC2-null cells was inhibited by the uPA inhibitor UK122, dexamethasone, and a FOXO inhibitor. uPA-knock-out mice developed fewer and smaller TSC2-null lung tumors, and introduction of uPA shRNA in tumor cells or amiloride-induced uPA inhibition reduced tumorigenesis in vivo These findings suggest that interference with the uPA-dependent pathway, when used along with rapamycin, might attenuate LAM progression and potentially other TSC-related disorders.

Luciferase Expression Allows Bioluminescence Imaging But Imposes Limitations on the Orthotopic Mouse (4T1) Model of Breast Cancer

Implantation of reporter-labeled tumor cells in an immunocompetent host involves a risk of their immune elimination. We have studied this effect in a mouse model of breast cancer after the orthotopic implantation of mammary gland adenocarcinoma 4T1 cells genetically labelled with luciferase (Luc). Mice were implanted with 4T1 cells and two derivative Luc-expressing clones 4T1luc2 and 4T1luc2D6 exhibiting equal in vitro growth rates. In vivo, the daughter 4T1luc2 clone exhibited nearly the same, and 4T1luc2D6, a lower growth rate than the parental cells. The metastatic potential of 4T1 variants was assessed by magnetic resonance, bioluminescent imaging, micro-computed tomography, and densitometry which detected 100-μm metastases in multiple organs and bones at the early stage of their development. After 3-4 weeks, 4T1 generated 11.4 ± 2.1, 4T1luc2D6, 4.5 ± 0.6; and 4T1luc2, <1 metastases per mouse, locations restricted to lungs and regional lymph nodes. Mice bearing Luc-expressing tumors developed IFN-γ response to the dominant CTL epitope of Luc. Induced by intradermal DNA-immunization, such response protected mice from the establishment of 4T1luc2-tumors. Our data show that natural or induced cellular response against the reporter restricts growth and metastatic activity of the reporter-labelled tumor cells. Such cells represent a powerful instrument for improving immunization technique for cancer vaccine applications.

[Role of octreotide and prednisolone in prophylactic of poshepatectomy liver failure. Experimental study]

AIM

Comparative morphologic assessment of the liver tissue response to the preoperative infusion of octreotide and prednisolon after the major hepatic resection was studied in rats.

MATERIAL AND METHODS

25 male Wistar rats weighing 230--280 g were used. All rats underwent 70--80% hepatectomy. The rats were divided into three groups according to the infusions before hepatectomy: group 1 (n=7) -- received octreotide, group 2 (n=8) -- prednisolone, group 3 (n=10) -- 0.9% saline solution as the control. Histologic features of the remnant liver were evaluated in the sacrificied rats after 72 hours post-hepatectomy.

RESULTS

In the group 1 we observed more rapid decrease of edema and tendency to the accelerated regeneration process of hepatocytes.

CONCLUSION

Octreotide infusion before the major hepatic resection may have protective effect on hepatocytes and accelerate the regeneration in the remnant liver.

[Confocal laser endomicroscopy in the diagnosis of diseases of biliary ducts]

Are clinical observations of various diseases of the bile ducts, including cholangiocarcinoma, developed with chronic diseases pancreato-biliary zone. Reflected the complexity of instrumental diagnostics at an early stage of the disease. For the first time at the given pathology diagnostic purposes was applied the method of probe confocal laser endomicroscopy allowed in all cases to clarify and verify the diagnosis. Describes the technique of the research, its results are compared with other diagnostic methods. The authors suggest that in the diagnosis of pancreatic and biliary zone method probe confocal laser endomicroscopy can be crucial in inefficiency or uninformative other methods.

[Pathomorphology of the uterus in decreased labor activity]

A comprehensive study of the pathomorphology of the corpus, lower segment, and placental bed of the uterus during powerless labor revealed the systematic pattern of uteroplacental complex abnormalities. In powerless labor, tonic uterine tonic component inactivity that develops in the presence of morphofunctional incompetence of the placental bed is determined by inadequate lacunar transformation of venous collectors of the corpus uteri and a forming lower segment. This leads to insufficient blood accumulation in the uterine venous vascular bed and to the development of hypotonic nonproductive birth pangs.

[Morphofunctional characteristics of the placenta, placental bed and myometrium in abnormal labor activity]

By comparison of dopplerometry results of right uterine artery and umbilical cords of a fetus with the histologic and morpho-stereometric data studies of the placenta, and also placental bed and myometrium in an operational material at Cesarian sections, a morphological basis of disturbances of communications in a functional system "mother-placenta-fetus" in hypotonic and hypertonic dysfunction of the uterus is revealed. The morphological picture of chronic placental insufficiency of the fetoplacentary form in the presence of pathological chorion immaturity is revealed in the development of weakness of activity. The uteroplacentary form of chronic placentaly insufficiency, incomplete gestation reorganization MPA and reduction morphometric parameters of a vascular channel miometrium documented formed discoordination of uterine muscles at child birth.