An Improved Ocular Impression Cytology Method: Quantitative Cell Transfer to Microscope Slides Using a Novel Polymer.

PURPOSE: To develop a more efficient impression cytology (IC) method for the transfer of ocular surface cells onto glass microscope slides for cytochemical, immunocytochemical, and immunofluorescence studies. METHODS: Cells are lifted off the ocular surface with a mixed cellulose ester membrane and then firmly attached to a glass slide using a novel triblock copolymer comprised of collagen type I, polyethylenimine and poly-L-lysine (CPP), and crosslinking cells and glass slide by heating and cooling. The membrane is removed intact after softening it with a butanol/ethanol solution. Transfer of cells is complete in about 10-15 minutes and is ready for staining. The efficiency of our cell transfer method was compared to current methods based on poly-L-lysine and albumin paste. RESULTS: Our method ensured almost complete transfer of cells. In contrast, the transfer of rabbit conjunctiva cells onto poly-L-lysine-covered slides was 37.5 ± 6.3% lower, and onto albumin-paste covered slides 62.5 ± 5.6% lower (mean ± SD); the transfer of rabbit goblet cells was even less efficient. The new method was also more efficient for transfer of cells from human oral mucosa obtained by IC. Transferred cells were successfully stained with H&E, chemiluminescence, and immunofluorescence agents. Using our method, we stained ocular surface cells for S100A4 and ATF4, both of which play a role in the pathophysiology of dry eye disease. We obtained similar results with oral mucosal cells, suggesting the generalizability of our approach. We propose an explanation for the strong adhesion of cells to the glass slide, which is based on their interactions with the triblock copolymer. CONCLUSIONS: We developed a novel approach for the efficient and rapid transfer of cells obtained by IC onto glass microscope slides using a novel copolymer. Compared to available methods, our improved approach makes IC robust and simple, and should increase its diagnostic yield and clinical applicability.

Techniques used to assess intussusceptive angiogenesis: A systematic review.

Intussusceptive angiogenesis (IA) is an important physiological form of angiogenesis in which an existing vessel splits in two by the formation of an intraluminal tissue pillar. The presence of these intraluminal pillars form the hallmark of ongoing IA in growing vascular beds. However, their visualization is technically challenging. The goal of this systematic review was to investigate which techniques are being used to identify intraluminal pillars and to formulate important points to keep in mind when studying IA. A systematic literature search resulted in 154 evaluated articles of which the majority (65%) provided sufficient data to unambiguously demonstrate the presence of intraluminal pillars. Scanning electron microscopy imaging of vascular corrosion casts and serial sectioning of ultrathin sections are the most used techniques. New methods such as serial block face scanning electron microscopy and micro computed tomography (µCT) are gaining importance. Moreover, our results indicate that IA was studied in a variety of animals and tissues. IA is a biologically very relevant form of angiogenesis. Techniques to visualize intraluminal pillars need to have a minimal resolution of 1 µm and should provide information on the 3D-nature of the pillars. Optimally, several techniques are combined to demonstrate ongoing IA.

Trends in cytopathology fellowship positions and vacancies over the past decade.

INTRODUCTION: Cytopathology is one of the most sought-after fellowships within pathology, with a lower fellowship vacancy rate compared with most other subspecialties. The Accreditation Council for Graduate Medical Education (ACGME) actively tracks annual program data for cytopathology fellowship programs, and evaluating this longitudinal data looking at trends in programs and positions over the past 10 years could provide insights into the future of cytopathology and its training programs. METHODS: Data obtained from the ACGME was examined in detail for all ACGME-accredited cytopathology fellowship programs over the past decade (2011-2021). Additional responses from program directors (PDs) from a 2021 American Society of Cytopathology (ASC) survey are also included. RESULTS: The total number of ACGME-approved cytopathology training programs and cytopathology fellowship positions remained relatively constant over the past 10 years, but the vacancy rate and number of programs with 1-2 unfilled spots has gradually but steadily risen over the past 6 years. In a 2021 ASC PD survey with 66% response rate, 53% of PDs reported having recruitment problems at least occasionally and 46% reported an increase in unexpected fellowship openings. CONCLUSIONS: Although the number of cytopathology positions has been relatively constant over the past decade, there has been a recent increase in cytopathology fellowship vacancies that may indicate changes in career choices or the job market, with fellows choosing jobs over additional fellowships, and potentially signal a growing shortage of fellowship-trained, Board-certified cytopathologists in the coming years.

Microscopy and Cell Biology: New Methods and New Questions.

Understanding the cellular basis of human health and disease requires the spatial resolution of microscopy and the molecular-level details provided by spectroscopy. This review highlights imaging methods at the intersection of microscopy and spectroscopy with applications in cell biology. Imaging methods are divided into three broad categories: fluorescence microscopy, label-free approaches, and imaging tools that can be applied to multiple imaging modalities. Just as these imaging methods allow researchers to address new biological questions, progress in biological sciences will drive the development of new imaging methods. We highlight four topics in cell biology that illustrate the need for new imaging tools: nanoparticle-cell interactions, intracellular redox chemistry, neuroscience, and the increasing use of spheroids and organoids. Overall, our goal is to provide a brief overview of individual imaging methods and highlight recent advances in the use of microscopy for cell biology.

Advances in materials for cellular applications (Review).

The goal of this review is to highlight materials that show exciting promise for either entirely new cellular-level applications or new approaches to long-standing biological challenges. The authors start with two more established materials, graphene and carbon nanotubes, and then progress to conducting polymers, followed by an overview of the microresonators, nanowires, and spasers used as intracellular lasers. These materials provide new approaches to gene and drug delivery, cellular regeneration, mechanical sensing, imaging, and the modulation and recording of cellular activity. Of specific interest is the comparison of these materials with existing technologies, the method of cellular delivery, and the all-encompassing challenge of biocompatibility. Concluding remarks examine the extension of these materials from cellular-level experiments to in vivo applications, including the method of activation: light, electricity, and ultrasound. Overall, these materials and their associated applications illustrate the most recent advances in material-cell interactions.

Bioinspired, nanoscale approaches in contemporary bioanalytics (Review).

The genesis for this topical review stems from the interdisciplinary Biointerfaces International conference 2016 (BI 2016) in Zurich, Switzerland, wherein the need for advances in analytical tools was both expressed and addressed. Pushing the limits of detection for characterizing individual components, such as single proteins, single drug-delivery vehicles, or probing single living cells in a more natural environment, will contribute to the understanding of the complex biomolecular systems central to a number of applications including medical diagnostics, tissue engineering, and drug screening and delivery. Accordingly, the authors begin with an overview of single nanoparticle analytics highlighting two emerging techniques and how they compare with existing techniques. The first is based on single particle tracking of nanoparticles tethered to a mobile supported lipid bilayer, enabling the simultaneous characterization of both size and composition of individual nanoparticles. The second technique is based on probing variations in the ionic conduction across nanoscale apertures for detection of not only nanoparticles but also membrane-tethered proteins, thereby allowing a multiparameter characterization of individual nanoscopic objects, addressing their size, shape, charge, and dipole moment. Subsequently, the authors lead into an example of an area of application that stands to benefit from such advances in bioanalytics, namely, the development of biomimetic lipid- and polymer-based assemblies as stimuli-responsive artificial organelles and nanocarriers designed to optimize delivery of next generation high-molecular-weight biological drugs. This in turn motivates the need for additional advanced techniques for investigating the cellular response to drug delivery, and so the review returns again to bioanalytics, in this case single-cell analysis, while highlighting a technique capable of probing and manipulating the content of individual living cells via fluidic force microscopy. In presenting a concerted movement in the field of bioinspired bioanalytics, positioned in the context of drug delivery, while also noting the critical role of surface modifications, it is the authors' aim to evaluate progress in the field of single component bioanalytics and to emphasize the impact of initiating and maintaining a fruitful dialogue among scientists, together with clinicians and industry, to guide future directions in this area and to steer innovation to successful translation.

The Next Frontier: Quantitative Biochemistry in Living Cells.

Researchers striving to convert biology into an exact science foremost rely on structural biology and biochemical reconstitution approaches to obtain quantitative data. However, cell biological research is moving at an ever-accelerating speed into areas where these approaches lose much of their edge. Intrinsically unstructured proteins and biochemical interaction networks composed of interchangeable, multivalent, and unspecific interactions pose unique challenges to quantitative biology, as do processes that occur in discrete cellular microenvironments. Here we argue that a conceptual change in our way of conducting biochemical experiments is required to take on these new challenges. We propose that reconstitution of cellular processes in vitro should be much more focused on mimicking the cellular environment in vivo, an approach that requires detailed knowledge of the material properties of cellular compartments, essentially requiring a material science of the cell. In a similar vein, we suggest that quantitative biochemical experiments in vitro should be accompanied by corresponding experiments in vivo, as many newly relevant cellular processes are highly context-dependent. In essence, this constitutes a call for chemical biologists to convert their discipline from a proof-of-principle science to an area that could rightfully be called quantitative biochemistry in living cells. In this essay, we discuss novel techniques and experimental strategies with regard to their potential to fulfill such ambitious aims.

Changing Trends and Practices in Cytopathology.

OBJECTIVE: To explore the current and anticipated changes in the practice of cytopathology. STUDY DESIGN: The present review is based on a review of recent literature and an evaluation of the authors' personal experiences. RESULTS AND CONCLUSION: In recent years the practice of cytopathology, nationwide and in our institute, has witnessed a major change affecting gynecologic and nongynecologic cytology. There has been a decline in the number of Papanicolaou tests which has affected the utilization of cytotechnologists and provoked a reorganization of their work flow. The "need to do more with less" in the era of targeted therapy/personalized medicine has resulted in an increasing preference for needle core biopsy when performing a rapid on-site evaluation. We feel that this change is unavoidable. It is pertinent that cytopathologists as a group recognize this change and prepare themselves and the trainees not only to become adapt but also to use this as an opportunity to discover the yet unexplored world of cytology.

Prevalence and predictors of unsatisfactory anal cytology tests in a cohort of gay and bisexual men in Sydney, Australia: baseline findings from the Study of the Prevention of Anal Cancer (SPANC).

Anal cytology has been suggested as a screening test for the anal cancer precursor high-grade squamous intraepithelial lesion (HSIL). We aimed to assess the prevalence and predictors of initial unsatisfactory anal cytology tests ('unsats'). The Study of the Prevention of Anal Cancer is a natural history study of anal human papillomavirus (HPV) and precancerous lesions among gay and bisexual men (GBM) of at least 35 years in Sydney, Australia. At each study visit, an anal swab is collected for cytological testing. Unsats are defined as slides with fewer than 2000 nucleated squamous cells and no abnormal cells. Among 617 GBM enrolled, the median age was 49 (range: 35-79) years and 220 (35.7%) were HIV positive. Initial unsats occurred in 61 (9.9%, 95% confidence interval: 7.6-12.5%), and 29 (4.7%, 95% confidence interval: 3.2-6.7%) remained unsatisfactory on repeat cytology. Initial unsats were associated with fewer lifetime anal-receptive partners with a condom (P=0.007); fewer recent anal-receptive sexual partners without a condom (P=0.005); never having had anal chlamydia (P=0.023) or gonorrhea (P=0.003); HIV-negative status (P=0.002); fewer total (P=0.002), low-risk (P=0.005), and high-risk (P=0.015) HPV types detected; lack of anal HPV18 detection (P=0.001); never having anally douched (P<0.001); and douching with soapy water (P=0.009) among those who douched. Unsats were less common among those with histologic HSIL (P=0.008) and nonsignificantly less common among those with fewer anal canal octants affected by HSIL (P=0.080), but were more common among those who felt more nervous (P=0.020) during the examination. Our findings suggest that unsats are more common among GBM with less receptive anal sexual experience. Avoiding douching with soapy water and strategies to aid patient relaxation during sampling may reduce the unsat rate.