A Biosemiotic Approach to the Problem of Structure and Agency

A human being is the simultaneous composite of several different levels of being, from atomic and subatomic to the level of complex social interaction, and these levels are nested within the individual hierarchically (lower levels giving rise to higher levels, etc.). One of the most important and influential approaches developed in the history of science has been that of systems theory and systemic thinking, in which the different levels of the hierarchy, and the interactions between those levels, are considered simultaneously. Although this model provides a comprehensive view of biological being, the transition from one level to the other is not well defined in it. Uexküll and Pauli (Advances: Journal of the Institute for 417 the Advancement of Health 3:158–174, 1986) suggested that semiosis is the translator of the events from one level to the other. From a psychological point of view, a myriad of semiotic events happen inside an individual, and it has been suggested that among other semiotic events, inner speech plays an important role in mediating personal agency. Dialogical theories of the self, Jungian psychology and hypnosis research evidence show that there is a semiotic multiplicity in human agency and consciousness, and that these multiple streams are all converge to a central semiotic singularity. I argue in this paper that by taking a biosemiotic point of view, human ‘agency’ may be defined as the ability of an individual to direct the incoming and internal streams of semioses and the ability to create an integrative and superordinate new stream of semiosis in addition to the upwardly and downwardly component ones, and how such a view might open a new door for research into the concept of human ‘personality’ and ‘agency’.     

CD8 T cells are essential for recovery from a respiratory vaccinia virus infection

The precise immune components required for protection against a respiratory Orthopoxvirus infection, such as human smallpox or monkeypox, remain to be fully identified. In this study, we used the virulent Western Reserve strain of vaccinia virus (VACV-WR) to model a primary respiratory Orthopoxvirus infection. Naive mice infected with VACV-WR mounted an early CD8 T cell response directed against dominant and subdominant VACV-WR Ags, followed by a CD4 T cell and Ig response. In contrast to other VACV-WR infection models that highlight the critical requirement for CD4 T cells and Ig, we found that only mice deficient in CD8 T cells presented with severe cachexia, pulmonary inflammation, viral dissemination, and 100% mortality. Depletion of CD8 T cells at specified times throughout infection highlighted that they perform their critical function between days 4 and 6 postinfection and that their protective requirement is critically dictated by initial viral load and virulence. Finally, the ability of adoptively transferred naive CD8 T cells to protect RAG(-/-) mice against a lethal VACV-WR infection demonstrated that they are both necessary and sufficient in protecting against a primary VACV-WR infection of the respiratory tract.     

OX40 Facilitates Control of a Persistent Virus Infection

During acute viral infections, clearance of the pathogen is followed by the contraction of the anti-viral T cell compartment. In contrast, T cell responses need to be maintained over a longer period of time during chronic viral infections in order to control viral replication and to avoid viral spreading. Much is known about inhibitory signals such as through PD-1 that limit T cell activity during chronic viral infection, but little is known about the stimulatory signals that allow maintenance of anti-viral T cells. Here, we show that the co-stimulatory molecule OX40 (CD134) is critically required in the context of persistent LCMV clone 13 infection. Anti-viral T cells express high levels of OX40 in the presence of their cognate antigen and T cells lacking the OX40 receptor fail to accumulate sufficiently. Moreover, the emergence of T cell dependent germinal center responses and LCMV-specific antibodies are severely impaired. Consequently, OX40-deficient mice fail to control LCMV clone 13 infection over time, highlighting the importance of this signaling pathway during persistent viral infection.     

Taming hyperactive hDNase I: Stable inducible expression of a hyperactive salt‐ and actin‐resistant variant of human deoxyribonuclease I in CHO cells

While the most common causes of clonal instability are DNA copy number loss and silencing, toxicity of the expressed protein(s) may also induce clonal instability. Human DNase I (hDNase I) is used therapeutically for the treatment of cystic fibrosis (CF) and may have potential benefit for use in systemic lupus erythematosus (SLE). hDNase I is an endonuclease that catalyzes degradation of extracellular DNA and is inhibited by both salt and G‐actin. Engineered versions of hDNase I, bearing multiple point mutations, which renders them Hyperactive, Salt‐ and Actin‐Resistant (HSAR‐hDNase I) have been developed previously. However, constitutive expression of HSAR‐hDNase I enzymes has been very challenging and, despite considerable efforts and screening thousands of clones, no stable clone capable of constitutive expression had been obtained. Here, we developed a regulated expression system for stable expression of an HSAR‐hDNase I in Chinese Hamster Ovary (CHO) cells. The HSAR‐hDNase I clones were stable and, upon induction, expressed enzymatically functional protein. Our findings suggest that degradation of host's DNA mediated by HSAR‐hDNase I during cell division is the likely cause of clonal instability observed in cells constitutively expressing this protein. Purified HSAR‐hDNase I was both hyperactive and resistant to inhibition by salt and G‐actin, resulting in an enzyme having ca. 10‐fold greater specific activity and the potential to be a superior therapeutic agent to wild type (WT) hDNase I. Furthermore, the ability to regulate hDNase I expression has enabled process development improvements that achieve higher cell growth and product titers while maintaining product quality. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 32:523–533, 2017     

Evaluation of heavy chain C‐terminal deletions on productivity and product quality of monoclonal antibodies in Chinese hamster ovary (CHO) cells

Monoclonal antibodies (mAbs) have been well established as potent therapeutic agents and are used to treat many different diseases. During cell culture production, antibody charge variants can be generated by cleavage of heavy chain (HC) C‐terminal lysine and proline amidation. Differences in levels of charge variants during manufacturing process changes make it challenging to demonstrate process comparability. In order to reduce heterogeneity and achieve consistent product quality, we generated and expressed antibodies with deletion of either HC C‐terminal lysine (‐K) or lysine and glycine (‐GK). Interestingly, clones that express antibodies lacking HC C‐terminal lysine (‐K) had considerably lower specific productivities compared to clones that expressed either wild type antibodies (WT) or antibodies lacking HC glycine and lysine (‐GK). While no measurable differences in antibody HC and LC mRNA levels, glycosylation and secretion were observed, our analysis suggests that the lower specific productivity of clones expressing antibody lacking HC C‐terminal lysine was due to slower antibody HC synthesis and faster antibody degradation. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:786–794, 2017     

Identification of methionine oxidation in human recombinant erythropoietin by mass spectrometry: Comparative isoform distribution and biological activity analysis

Background: Oxidative degradation of human recombinant erythropoietin (hrEPO) may occur in manufacturing process or therapeutic applications. This unfavorable alteration may render EPO inefficient or inactive. We investigated the effect of methionine/54 oxidative changes on the amino acid sequences, glycoform distribution and biological activity of hrEPO. Methods: Mass spectrometry was applied to verify the sequence and determine the methionine oxidation level of hrEPO. Isoform distribution was studied by capillary zone electrophoresis method. In vivo normocythemic mice assay was used to assess the biological activity of three different batches (A, B, and C) of the proteins. Results: Nano-LC/ESI/MS/MS data analyses confirmed the amino acid sequences of all samples. The calculated area percent of three isoforms (2–4 of the 8 obtained isoforms) were decreased in samples of C, B, and A with 27.3, 16.7, and 6.8% of oxidation, respectively. Specific activities were estimated as 53671.54, 95826.47, and 112994.93?mg/mL for the samples of A, B, and C, respectively. Conclusion: The observed decrease in hrEPO biological activity, caused by increasing methionine oxidation levels, was rather independent of its amino acid structure and mainly associated with the higher contents of acidic isoforms.     

Effects of age and leg length upon central loop of the Gastrocnemius-soleus H-reflex latency

Background  

central loop of the gastrocnemius-soleus H-reflex latency (T_c) that looks promising in the diagnosis of S1 radiculopathy; has been investigated in a few studies and only two of them have focused on the constitutional factors affecting it. Although leg length has been shown to contribute to the T_c, the role of age is controversial. More confusing, none of the previously performed studies have used strict criteria to rule out subclinical neuropathy, so the results could be misleading. This study has been performed to determine the influence of leg length and age on T_c among a carefully selected group of healthy volunteers.