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We describe the current Good Manufacturing Practice (cGMP) production and subsequent characterization of eOD-GT8 60mer, a glycosylated self-assembling nanoparticle HIV-1 vaccine candidate and germline targeting priming immunogen. Production was carried out via transient expression in the human embryonic kidney 293 (HEK293) cell line followed by a combination of purification techniques. A large-scale cGMP (200 L) production run yielded 354 mg of the purified eOD-GT8 60mer drug product material, which was formulated at 1 mg/mL in 10% sucrose in phosphate-buffered saline (PBS) at pH 7.2. The clinical trial material was comprehensively characterized for purity, antigenicity, glycan composition, amino acid sequence, and aggregation and by several safety-related tests during cGMP lot release. A comparison of the purified products produced at the 1 L scale and 200 L cGMP scale demonstrated the consistency and robustness of the transient transfection upstream process and the downstream purification strategies. The cGMP clinical trial material was tested in a Phase 1 clinical trial (NCT03547245), is currently being stored at −80 °C, and is on a stability testing program as per regulatory guidelines. The methods described here illustrate the utility of transient transfection for cGMP production of complex products such as glycosylated self-assembling nanoparticles. [ABSTRACT FROM AUTHOR]

Therapeutic proteins, including monoclonal antibodies, are typically manufactured using clonally derived, stable host cell lines, since consistent and predictable cell culture performance is highly desirable. However, selecting and preparing banks of stable clones takes considerable time, which inevitably extends overall development timelines for new therapeutics by delaying the start of subsequent activities, such as the scale‐up of manufacturing processes. In the context of the coronavirus disease 2019 (COVID‐19) pandemic, with its intense pressure for accelerated development strategies, we used a novel transposon‐based Leap‐In Transposase® system to rapidly generate high‐titer stable pools and then used them directly for large scale‐manufacturing of an anti‐severe acute respiratory syndrome coronavirus 2 monoclonal antibody under cGMP. We performed the safety testing of our non‐clonal cell bank, then used it to produce material at a 200L‐scale for preclinical safety studies and formulation development work, and thereafter at 2000L scale for supply of material for a Phase 1 clinical trial. Testing demonstrated the comparability of critical product qualities between the two scales and, more importantly, that our final clinical trial product met all pre‐set product quality specifications. The above expediated approach provided clinical trial material within 4.5 months, in comparison to 12–14 months for production of clinical trial material via the conventional approach. [ABSTRACT FROM AUTHOR]

Part I of this comprehensive review article dealt exclusively with the use of chlorhexidine in the practice of dentistry and dental hygiene. While it is universally accepted that chlorhexidine is one of the most effective antimicrobial agents for intraoral application, many other substances have also been proven to be effective when applied topically. Thus, Part II of this article provides in-depth descriptions of alternative agents for antimicrobial use in dentistry, by both the patient at home and the professional in the dental office. [ABSTRACT FROM AUTHOR]

Bacteremia is a common occurrence in patients with periodontal diseases, even simple gingivitis. Tooth brushing, especially improper and/or overzealous tooth brushing, routinely occasions a significantly perceptible elevation in the quantity of oral-origin microorganisms in the circulating blood. Initial therapy, whether a routine prophylaxis in a gingivitis case, or scaling and root planing in a periodontitis patient, always leads to bacteremia, often massive; hitherto, most such bacteremias have been assumed to be both transient and inconsequential for the patient's systemic health. This assumption is no longer tenable in the light of new clinical and scientific knowledge. The purposes of the present article are: 1) to critically review the contemporary use of antimicrobial agents in dental and dental hygiene practice in the USA and internationally; 2) to revisit and review the peculiarities that characterize inflammatory gingival/periodontal disorders which may demand more aggressive use of antimicrobial agents now and in the future; and 3) to conceptualize the emerging treatment concepts that are targeted towards treatment of gingival/periodontal diseases as acutely contagious clinical entities. [ABSTRACT FROM AUTHOR]

The article presents the clinical and scientific approaches in treating gingival enlargement. It mentions that diagnosis of gingival enlargement is critical if an appropriate treatment measures for gingival enlargement are to be instituted. The determination of whether the enlargement is inflammatory, fibrous or a combination as well as the determination of the health status is important. It further states that microscopic examination of tissue may be a great benefit for the dentist to determine the course of therapy to be given to the patient.

This study investigated the marginal fit of the prefabricated crowns for the Ha-Ti implant system using scanning electron microscopy. The results demonstrated that the mean gap between the crown margin and the implant base was less than 3 μm following simulated ceramic firing and continuous loading in vitro. [ABSTRACT FROM AUTHOR]

Abstract: We describe the properties of BG505 SOSIP.664 HIV‐1 envelope glycoprotein trimers produced under current Good Manufacturing Practice (cGMP) conditions. These proteins are the first of a new generation of native‐like trimers that are the basis for many structure‐guided immunogen development programs aimed at devising how to induce broadly neutralizing antibodies (bNAbs) to HIV‐1 by vaccination. The successful translation of this prototype demonstrates the feasibility of producing similar immunogens on an appropriate scale and of an acceptable quality for Phase I experimental medicine clinical trials. BG505 SOSIP.664 trimers are extensively glycosylated, contain numerous disulfide bonds and require proteolytic cleavage, all properties that pose a substantial challenge to cGMP production. Our strategy involved creating a stable CHO cell line that was adapted to serum‐free culture conditions to produce envelope glycoproteins. The trimers were then purified by chromatographic methods using a 2G12 bNAb affinity column and size‐exclusion chromatography. The chosen procedures allowed any adventitious viruses to be cleared from the final product to the required extent of >12 log10. The final cGMP production run yielded 3.52 g (peptidic mass) of fully purified trimers (Drug Substance) from a 200 L bioreactor, a notable yield for such a complex glycoprotein. The purified trimers were fully native‐like as judged by negative‐stain electron microscopy, and were stable over a multi‐month period at room temperature or below and for at least 1 week at 50°C. Their antigenicity, disulfide bond patterns, and glycan composition were consistent with trimers produced on a research laboratory scale. The methods reported here should pave the way for the cGMP production of other native‐like Env glycoprotein trimers of various designs and genotypes. [ABSTRACT FROM AUTHOR]

The two major afflictions of the oral cavity are dental caries and gingival/periodontal disease. While microorganisms have long been acknowledged as important etiologic factors, the most recent research data demonstrate that both of these pathologic conditions have a strong hereditary base, i.e., even in the presence of putative pathogenic microorganisms, if the host individual is not genetically susceptible, ensuing disease will be mild or even nonexistent. In the face of this evidence for heritability of the two major oral diseases, we evaluated what educational experiences in genetics were provided to students in U.S. dental schools and dental hygiene programs in 2003-04. Our survey of fifty-four dental schools revealed that only one requires a formal genetics course before admission, and only six incorporate a required genetics course within the dental curriculum. Of the 264 dental hygiene programs surveyed, none require a formal genetics course as a prerequisite for admission, and none require a formal genetics course within their curricula. The enormous successes, and future promise, of the Human Genome Project suggest that genetics will soon dominate the future of medicine and dentistry, in prediction of diseases, disease diagnosis, and, eventually, therapy for genetically based disorders. It is therefore incumbent upon dental and dental hygiene education programs to provide genetics education for tomorrow's practitioners. [ABSTRACT FROM AUTHOR]

When measured by radioinimunoassay, fibroblasts derived from the overgrown gingivae of phenytoin-treated epileptic individuals synthesize and release elevated amounts of collagenase in vitro, as compared to similar-appearing fibroblasts from normal, rion-phenytoin-treated persons. However, it appears that much of the immunoreactive enzyme is unable to degrade reconstituted collagen in culture. This preliminary finding in 9 different strains of cells indicates that reduced collagenase activity by a subpopulation of cells may contribute to the development of phenytom-induced gingival overgrowth. [ABSTRACT FROM AUTHOR]

In a cross-sectional, epidemiological study of phenytoin induced gingival overgrowth in 77 institutionalized persons with epilepsy, the severity of the gum lesions was quantified by means of a precise new technique. Lesion severity was then compared statistically to other clinical and laboratory parameters. Positive correlations were detected between overgrowth severity and gingival inflammation, probing depths, calculus accumulation, plaque score and the measurement gingival margin to mucogingival junction (GM-MGJ). No correlation was observed between lesion severity and patients age, daily drug dosage, plasma or saliva phenytoin level, or salivary concentration of the major phenytoin metabolite. [ABSTRACT FROM AUTHOR]

Phenytoin (Dilantin®) induces gingival overgrowth characterized by an accumulation of connective tissue. The cell-to-matrix ratio in the mature lesion is normal, yet there must be more fibroblasts per oral cavity if there is excessive tissue mass. Using a mongrel cat model system, we studied the early, developing phenytoin-induced lesion by quantitating fibroblasts per unit of tissue in papilla biopsies collected over a 3-month period of daily drug administration. At 6 and 8 weeks, the number of fibroblasts per unit of tissue increased dramatically. By 3 months, as the lesions matured, the fibroblast-to-matrix ratio returned to normal. We suggest that the drug interacts with resident gingival fibroblasts, causes them to proliferate and thus induces a true, but transient, hypercellularity. Cell division then appears to slow or cease, and rapid production of connective tissue matrix ensues, returning the cell-to-matrix ratio to normal. [ABSTRACT FROM AUTHOR]

The responsiveness of human gingival fibroblast populations to cyclosporin A (CsA) and its principal metabolite, hydroxycyclosporine (M17), was evaluated in cell culture. Gingival fibroblasts exhibited a dose-dependent accumulation and bell-shaped distribution of dansylated CsA. A 100-fold excess of non-labeled CsA prevented the accumulation of the fluorescent probe in the fibroblasts. Both CsA (400 ng/ml) and M17 (100 ng/ml) stimulated mean gingival fibroblast cell number to 23.2% and 36.7% above controls, and reduced mean collagen production by 37.7% and 37.4% below controls, respectively: however, neither CsA nor M17 affected mean protein production in comparison to control cultures, Analyses of responses to CsA and M17 by ligand-accumulating and non-accumulating fibroblasts sorted out from the parent cultures did not provide consistent interstrain responses either by cells representing the upper quartile of fluorescence or cells representing the bottom quartiles of fluorescence. These data demonstrate that CsA is accumulated by gingival fibroblasts and that CsA and M17 are potent modulators of gingival fibroblast phenotype. [ABSTRACT FROM AUTHOR]

Deciphering the relative roles of heredity and environmental factors ("nature vs. nurture") in the pathogenesis of dental caries and diseases of the periodontium has occupied clinical and basic researchers for decades. Success in the endeavor has come more easily in the case of caries; the complex interactions that occur between host-response mechanisms and putative microbiologic pathogens in periodontal disease have made elucidation of genetic factors in disease susceptibility more difficult. In addition, during the 30-year period between 1958 and 1987, only meager resources were targeted toward the "nature" side of the nature/nurture dipole in periodontology. In this article, we present a brief history of the development of genetic epistemology, then describe the three main research mechanisms by which questions about the hereditary component of diseases in humans can be addressed. A critical discussion of the evidence for a hereditary component in caries susceptibility is next presented, also from a historical perspective. The evolution of knowledge concerning possible genetic ("endogenous", "idiotypic") factors in the pathogenesis of inflammatory periodontal disease is initiated with an analysis of some foreign- language (primarily German) literature that is likely to be unfamiliar to the reader. We identify a turning point at about 1960, when the periodontal research community turned away from genetics in favor of microbiology research. During the past five years, investigators have re-initiated the search for the hereditary component in susceptibility to common adult periodontal disease; this small but growing body of literature is reviewed. Recent applications of in vitro methods for genetic analyses in periodontal research are presented, with an eye toward a future in which persons who are at risk--genetically predisposed-- to periodontal disease may be identified and targeted for interventive strategies. Critical is the realization that genes and environment do not act independently of each other; the appearance or magnitude of heritability may differ with various environments. [ABSTRACT FROM AUTHOR]

This article discusses the results of a research study conducted to determine the pathogenesis of gingival overgrowth and swelling induced by phenytoin. The potential impact of cyclosporine-A and other dihydropyridines in inducing gingival overgrowth and swelling is also considered. The researchers propose that these three classes of drugs share a common property of affecting cellular calcium metabolism, which they suggest may cause their similar action on connective tissue cells. They find the cellular response of gingival overgrowth to seven different drugs to be unpredictable.

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