Avian embryos and related cell lines: A convenient platform for recombinant proteins and vaccine production

Chick embryos are a significant historical research model in basic and applied sciences. The embryonated eggs have been used for virus inoculation in order to vaccine production for nearly a century. Recently, avian eggs and cell lines derived from embryonated eggs have found wide application in biotechnology. This review will discuss about the unique characteristics of avian eggs in terms of safety, large scale and economical production of recombinant proteins. This system also provides the human‐like glycosylation on target proteins and therefore can be considered as a suitable host for biomanufacturing of humanized monoclonal antibodies and therapeutic proteins. Avian derived cell lines are an alternative for rapid vaccine manufacturing during a pandemic. Based on the latest knowledge in cell and animal transgenesis, the currently available germ cell‐mediated gene transfer system provides a more efficient strategy in gene targeting and creation of transgenic birds that lead to advancements in industrial, biotechnology, and biological research applications. This review covers the recent development of avian fertilized eggs and related cell lines in a variety of human biopharmaceuticals and viral vaccine manufacturing.     

Matrix remodeling in experimental and human heart failure: a possible regulatory role for TIMP-3

In the failing heart, an imbalance in matrix metalloproteinases (MMPs) and their biological regulators, the tissue inhibitors of MMPs (TIMPs), may result in cardiac dilatation from matrix degradation. We hypothesized that a reduction of myocardial TIMP-3 is associated with adverse matrix remodeling in both human and experimental heart failure. Cardiomyopathic hamsters at age 15 wk (normal), 25 wk (compensated stage), and 35 wk (overt failure) were compared with age-matched normal controls. MMP activity (gelatinase bioassay) was increased in cardiomyopathic hearts (P = 0.03) and peaked during the transition to overt heart failure. TIMP-3 content (immunoblot) was decreased compared with normal controls (74 +/- 5% at 25 wk, 69 +/- 10% at 35 wk; P = 0.001) and its reduction was associated with increased MMP activity (r = -0.6; P = 0.004). TIMP-1 increased progressively (P = 0.001), whereas TIMP-2, TIMP-4, and MMP protein levels were unchanged. Myocardial collagen (hydroxyproline content) increased with time during the progression to end-stage cardiac failure (P < 0.0001). Collagen synthesis ([(14)C]proline uptake) was elevated in cardiomyopathy at 15 and 25 wk (P < 0.05). The collagen cross-linking ratio (insoluble:soluble collagen) was reduced (P = 0.003) as the left ventricle dilated. By confocal microscopy restricted to viable myocardium, collagen content was reduced (P = 0.04) with fragmentation (P < 0.0001) and thinning (P = 0.003) of perimysial collagen fibers. Similarly, patients with end-stage congestive heart failure (n = 7) compared with nonfailing controls (n = 2) had elevated gelatinase MMP activity (P = 0.02) associated with isolated reductions in TIMP-3 (55 +/- 5% of normal; P = 0.003). Reductions of TIMP-3 parallel adverse matrix remodeling in the cardiomyopathic hamster and the failing human heart. TIMP-3 may contribute to the regulation of myocardial remodeling and its reduction may promote a transition from compensated to end-stage congestive heart failure.     

Generation of tolerogenic dendritic cells using Lactobacillus rhamnosus and Lactobacillus delbrueckii as tolerogenic probiotics

Systemic lupus erythematosus (SLE) concurs with excessive uncontrolled inflammatory immune responses that lead to the loss of immune tolerance. Dendritic cells (DCs) are important and determinant immune cells that regulate immune responses. Tolerogenic DCs with regulatory markers and cytokines could induce regulatory immune cells and responses. Tolerogenic probiotics are capable of producing regulatory DCs from monocytes in in vitro conditions. The purpose of this study was to evaluate the effect of Lactobacillus delbrueckii and Lactobacillus rhamnosus on the production of DCs in an in vitro condition. Peripheral blood mononuclear cells were isolated from the healthy and SLE donors. Monocytes were cultured with optimized concentrations of granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) and interleukin 4 (IL‐4) to produce immature DCs (IDCs). An IDC uptake assay was performed, and IDCs of healthy and SLE donors were divided into three subgroups following 48 hours of treatment with GM‐CSF and IL‐4, along with L. delbrueckii, L. rhamnosus, and mixed probiotics for the production of tolerogenic DCs. The surface expression of Human Leukocyte Antigen‐antigen D Related (HLA‐DR), CD86, CD80, CD83, CD1a, and CD14 was analyzed using flow cytometry, and the gene expression levels of indoleamine 2,3‐dioxygenase (IDO), IL‐10, and IL‐12 were measured using real‐time polymerase chain reaction. We observed significantly reduced expression of costimulatory molecules and other surface markers in the probiotic‐induced mature DCs (MDCs) in both healthy and SLE donor groups in comparison with lipopolysaccharide (LPS)‐induced MDCs. In addition, the expression of IDO and IL‐10 increased, whereas IL‐12 decreased significantly in probiotic‐induced MDCs compared with LPS‐induced MDCs. IDCs and especially mature tolerogenic DC of SLE patients highly expressed IDO. The results of the current study suggested that live probiotics could modify properties of DCs to modulatory cells, which might contribute to the induction of tolerance and renovation of immune hemostasis.     

Tumour cell‐intrinsic CTLA4 regulates PD‐L1 expression in non‐small cell lung cancer

Cytotoxic T lymphocyte antigen 4 (CTLA4) and programmed cell death protein 1 (PD‐1) are immune checkpoint proteins expressed in T cells. Although CTLA4 expression was found in multiple tumours including non‐small cell lung cancer (NSCLC) tissues and cells, its function in tumour cells is unknown. Recently, PD‐1 was found to be expressed in melanoma cells and to promote tumorigenesis. We found that CTLA4 was expressed in a subset of NSCLC cell lines and in a subgroup of cancer cells within the lung cancer tissues. We further found that in NSCLC cells, anti‐CTLA4 antibody can induce PD‐L1 expression, which is mediated by CTLA4 and the EGFR pathway involving phosphorylation of MEK and ERK. In CTLA4 knockout cells, EGFR knockout cells or in the presence of an EGFR tyrosine kinase inhibitor, anti‐CTLA4 antibody was not able to induce PD‐L1 expression in NSCLC cells. Moreover, anti‐CTLA4 antibody promoted NSCLC cell proliferation in vitro and tumour growth in vivo in the absence of adaptive immunity. These results suggest that tumour cell‐intrinsic CTLA4 can regulate PD‐L1 expression and cell proliferation, and that anti‐CTLA4 antibody, by binding to the tumour cell‐intrinsic CTLA4, may result in the activation of the EGFR pathway in cancer cells.     

Visceral Leishmaniasis in Southwestern Iran: A Retrospective Clinico-Hematological Analysis of 380 Consecutive Hospitalized Cases (1999–2014)

Visceral Leishmaniasis (VL) is an endemic parasitic disease and remains as a major health concern in southwestern Iran. The current study describes clinico-hematological, epidemiological and therapeutic features of VL cases, admitted to university-affiliated hospitals, during 1999–2014 in Fars province, southwestern Iran. A total of 380 VL cases were recorded during a 16 years period, giving an average annual admission of 23.75 cases/year in which 217 (57.1%) were male and 163 (42.9%) were female. Mean age of the patients was 3.7 years. The majority of the cases (91.5%) were ≤ 5 years old. Bone-marrow aspiration detected Leishmania amastigotes only in 26.6% of cases. Fever (98.1%), abdominal protrusion (65.1%) and hepatosplenomegaly (63.7%) were the most common clinical presentations of the patients. Pancytopenia was noted in 43.1, anemia in 87.3 and thrombocytopenia in 64% of cases. Increase in the level of AST (aspartate aminotransferase), ALT (alanine aminotransferase), alkaline phosphatase, LDH (lactate dehydrogenase) and CRP (C-Reactive Proteins) were seen in 84.9, 53.6, 44.4, 72.5 and 83.1% of cases, respectively. Mortality was noted in 5.3% of cases. Deranged haemato-biochemical parameters including total and direct bilirubin, PLT (platelet) and pancytopenia were significantly contributed to mortality from VL. Moreover, clinical features such as severe splenomegaly as well as bacterial infections were meaningfully contributed to death from VL. The majority of patients (74.9%) were treated with meglumine antimoniate. Amphotericin B was administrated in 59 of cases, 11 of them were initially treated with meglumine antimoniate with a shift to amphotericin B, because of treatment failure. Findings of the current study demonstrated that VL is present in southwest of Iran with a fairly continual rate during the last 16 years period. Deranged haemato-biochemical parameters along with severe splenomegaly contributed to mortality from VL.     

Effect of Ferula assafoetida essential oil on some biological and behavioral traits of Trichogramma embryophagum and T. evanescens

Fumigant toxicity of the essential oil of Ferula assafoetida L. (Umbelliferae), a potent botanical insecticide against carob moth, was investigated under laboratory conditions on the fitness of two carob moth egg parasitoids, Trichogramma embryophagum (Hartig) and T. evanescens Westwood (Hymenoptera: Trichogrammatidae). The fertility life table parameters were assessed for both species at two different treatments, essential oil and ethanol as control. Although these two species were not affected similarly by the essential oil, exposure to 877 ppm (LC₀₁) in both species significantly reduced the longevity and fecundity of females, as well as the survival, developmental time, wing normality and sex ratio of their progeny. Effects of the essential oil on reproductive behavior of Trichogramma species were also investigated. Under oil treatment, despite that mate searching time increased, the percentage of mating occurrence, the duration of copulation, and sex ratio of F1 progeny declined. Given the negative effects of F. assafoetida essential oil on the two tested wasps, complementary studies are needed to develop the best management strategy for using the oil as environmentally friendly compound in combination with Trichogramma wasps against herbivorous insects.     

Carnosine and Histidine Supplementation Blunt Lead-Induced Reproductive Toxicity through Antioxidative and Mitochondria-Dependent Mechanisms

Biological Trace Element Research - Lead (Pb)-induced reproductive toxicity is a well-characterized adverse effect associated with this heavy metal. It has been found that Pb exposure is associated...     

Effect of the Heavy Metals on Developmental Stages of Ovule,Pollen, and Root Proteins in <Emphasis Type="Italic">Reseda lutea</Emphasis> L. (Resedaceae)

Heavy metals are some of the most important environmental pollutants. Excessive amounts of heavy metals adversely affect plant growth and development. Also, the presence of elevated levels of heavy metal ions triggers a wide range of cellular responses including changes in gene expression and synthesis of metal-detoxifying peptides. The overall objective of this research was to elucidate some microscopic effects of heavy metals on the formation, development, and structure of pollen, ovule, and embryo and also root proteins in Reseda lutea L. For this purpose, the vicinity of Ahangaran lead–zinc mine (Hamedan, Iran) was chosen as a polluted area where amount of some heavy metals was several times higher than the natural soils. Flowers and young buds were collected from non-polluted and polluted plants, fixed in FAA₇₀, and studied during developmental stages by light microscopy. The results showed that heavy metals can cause some abnormalities during the pollen and ovule developmental process. The number of pollen grains was decreased, and their shape was changed. Increasing in thickness of the callosic wall and stabilizing of tapetum layer were observed in polluted plants. Asymmetrical formation of ovular integuments, degradation of egg apparatus, irregular formation of embryo sac, considerable vacuolation of embryonic cells, and degeneration of embryo in the late stage of heart-shaped embryo are the results of heavy metal pollution. For protein studies, young roots were harvested from plants exposed to pollution and non-exposed to pollution at the same time. Root proteins were extracted and studied by electrophoresis. The results revealed that some new proteins were synthesized in polluted samples that probably elevate plant tolerance to heavy metals.