Updated: 26 November 2020

Beakers, bunsen burners, and microscopes are the images that often come to mind while thinking about 'science', but there's obviously much more to the field than that when it comes to imagery. 

The science we do at PMI covers a wide range of subjects, from airway deposition to genotoxicity analysis, and more. Within that scope, there are many moments of visual beauty that can capture the eye and increase our understanding of the field. Here, we've collected some images to offer more insight into the beauty of science, and how that beauty lets us learn more about an array of outcomes to help grow the global database of research.


Pink Buccal

Spot the blue spots

Magnified 20 times, this 3D human organotypic buccal #cell culture consists of normal, human-derived oral epithelial cells. Red-stained E-cadherin, a calcium-dependent adhesion molecule, acts as an adhesion receptor in the adherens junctions. Brown-stained Ki67 as a proliferation marker is an excellent marker to determine the growth fraction of a given cell population.  

Click here to read how we use buccal cell cultures for the toxicological assessment of our smoke-free products in vitro.  


Cytoskeletal Component

Vimentin, in brown in this human kidney tissue section, is the major cytoskeletal component of mesenchymal cells. As an intermediate filament protein, it is a member of the intermediate filament family. 

Click here to discover a study where vimentin expression was explored.  

Spot the blue spots

Spot the Blue Spots

Spot the blue spots

At a closer look one can spot the blue spots. Those are cell nuclei in this 3D human organotypic buccal cell culture. The elegant brown E-cadherin is a calcium-dependent adhesion molecule and acts as an adhesion receptor in the adherens junctions, with important functions in cell adhesion and cell signaling.  

What is the biological impact of exposure to Platform 1 aerosol on E-cadherin expression in human 3D organotypic buccal cell cultures? 


Vibrant Violet

Within this 3D human organotypic buccal cell culture, hematoxylin stains the nuclei blue while eosin stains the extracellular matrix and cytoplasm in varying degrees of pink. The vibrant violet cell culture consists of normal, human-derived oral epithelial cells and we are seeing the image magnified 20 times.  

Learn how these cell cultures play an important part in the toxicological assessment of our smoke-free products in vitro.  

Vibrant Violet

"The most striking aspect of science and therefore of the nature that surrounds us is certainly the incredible work done by natural selection…"

David Bovard collage

David Bovard, Scientist – Microphysiological Systems, shares the aspects of science that are beautiful to him. He observes unexpected beauty in his research and has captured these beautiful images of cells, cell cultures and spheroids.

Learn why he thinks science is beautiful, which of his images are most memorable and about his favorite technique to use on cells.


Circular Scope

This circular HeLa cell culture (comprised of immortal cells) acts as a positive control for RNAScope® technology – an in situ hybridization assay that detects RNA expression of target genes in various human cell cultures. Here, the target gene expression, human peptidylprolyl isomerase B, a "housekeeping gene" involved in basic cellular function is shown in red.

Read about other applications of RNAscope technology.

Circular Scope

A Sequence of Plants

A Sequence of Plants

Sanger sequencing is used to show the A, T, C, G nucleotide sequence of DNA (developed by Nobel prize winner Frederick Sanger). Here, Sanger sequencing is used to show the tobacco plant DNA sequence as a chromatogram. Higher peaks correspond to higher intensity fluorescence signal.

Find out more about our plant sequencing.


Adhesive Appendix

Immunohistochemical (IHC) staining of this human appendix tissue section marks E-cadherin molecules in brown. E-cadherin is a calcium-binding-dependent cell adhesion molecule – essentially it helps cells bind to other cells. Hematoxylin is used as a counterstain to contrast cell nuclei in blue.

Click here to learn how E-cadherin is affected by exposure to total particulate matter of Platform 1 aerosol.

Adhesive Appendix

IHC Tonsil Tissue

IHC Tonsil Tissue

This human tonsil tissue IHC staining colors the basal epithelial cell marker p63 and cytokeratin 5 (CK5) in brown, while cytokeratin 14 (CK14) is colored red. CK5 is seen as brown membranous staining, while p63 staining is found in the nuclei. Where p63 is absent in the nuclei a blue hematoxylin counterstain is seen.

To learn about IHC alternatives, click here.



Regions of brown staining unveil the protein vimentin in this section of human appendix tissue. Vimentin is an intermediate filament protein that’s a major component of the cytoskeleton of mesenchymal cells.

In this bronchial epithelial cells study, we evaluated vimentin expression.




Immunohistochemical staining in brown shows the protein Ki67, a marker for cell proliferation (multiplication) found in B-cells (a type of white blood cells) in this human tonsil tissue. We use this to visualize the growth fraction in this cell population.

Find out about Ki67.


Cytoskeletal Green

These fluorescent cells have been stained green to show their cytokeratin 5, a protein that helps form the cytoskeleton. This primary human bronchial culture has been used to prepare 3D organotypic lung tissue for use in our organ-on-a-chip devices.

Read about how we use other fluorescent dyed cells in our research.

Cytoskeletal Green

Cytokeratin 5

Cytokeratin 5

Red, brown, and blue staining show CK5, p63, and cell nuclei, respectively. CK5 – also known as cytokeratin 5 – is a protein that helps to compose the filaments that create the cytoskeleton of the basal epithelial cells in this human tonsil tissue, p63 is a marker for these basal epithelia cells.

Learn more about p63's use in our other publications.


Nasal Mucin

This 3D human organotypic nasal cell culture is stained to display Muc5AC (in brown) and nuclei (in blue). Mucus in the nasal pathway is made up of water, ions, and gel-forming mucin glycoproteins, among other components. Muc5AC is a mucin glycoprotein secreted by specialized goblet cells (which produce mucus).

Read some of our goblet cell research here.

Nasal mucin



CD68 is a protein expressed by macrophages and cells in the monocyte lineage (white blood cells). IHC staining in this appendix has colored the CD68 proteins in brown, while a hematoxylin counterstain identifies cell nuclei in blue.

Learn about alternatives to IHC here.


Fluorescent p63

This 3D nasal cell culture immunofluorescence staining displays the transcription factor p63 in green and nuclei in blue. The transcription factor acts as a sequence-specific DNA-binding transcriptional activator or repressor (it can stop or start the transcription of certain DNA sequences). In this 40x magnified image, p63 is used as a marker for basal cells.

Learn more about our 3D cell culture systems.

Fluorescent p63

Smooth Guts

Smooth Guts

The protein smooth muscle actin (SMA) is stained brown in this human appendix tissue that’s a good positive control for SMA because of its muscle layers. This protein’s expression is regulated by hormones and cell proliferation (multiplication).

For information about our gut research, read this.


A Study in Indigo

Hematoxylin & eosin staining shows the mucosa (layers of cells containing mucous glands) of an appendix. From this indigo image you can see cross-sections of the glands – circular regions encapsulated in a darker purple.

Read about our gut research with this intestine-on-a-chip study.

A Study in Pink

Culture of Violets

Culture of Violets H&E stain

One of the most prominent tissue stains in histology (the study of microanatomy) is hematoxylin and eosin. Hematoxylin dyes the nuclei in this 3D human organotypic nasal cell culture blue, eosin dyes the extracellular matrix and cytoplasm pink, while the stain Alcian Blue dyes the mucin molecules (a component of mucus) blue.

Learn how we use nasal cell cultures in Platform 2 testing.


Nosy Fox

Within this 3D human organotypic nasal cell culture, immunohistochemical staining highlights the protein FOXJ1 in brown while hematoxylin stains the nuclei blue. The FOXJ1 protein is part of the forkhead box (Fox) family of transcription factors that play key roles in cell proliferation and differentiation.

Cultures like these are used in tissue research for Platform 1, which you can read here.

Nosy Fox FOXJ1 proteins



This speckled island of blue and green is a human induced pluripotent stem cell culture. These undifferentiated cells were cultured by one of our first R&D postdoctoral fellows for use in an in vitro neuronal model of Parkinson’s disease.

Learn about the experiences of our postdoctoral fellows here.



Staining for albumin (green), nuclei (blue), and α-smooth muscle actin (red) of human liver cells and human hepatic stellate cells create this triple-colored façade. These 10x magnified cells were cultured together to develop a more complex model system of the human liver.

For a look into why we need more complex liver systems, read our lung/liver-on-a-chip study.

Human liver cells stained for albumin (in green) and stellate cells (in red)

Sticky Cells

Sticky Cells 3D organotypic nasal culture

This 3D human organotypic nasal cell culture shows blue-stained nuclei, and red-stained E-cadherin; a cell-cell adhesion molecule that plays a key role in cell behavior and tissue formation. 3D cell cultures more closely resemble the physiology of tissue in the human body, compared to 2D cultures or animal models.

Read more about our 3D nasal cell cultures here.


Electric Blue

How can we tell what DNA markers tobacco plants have? By separating the amplified microsatellite marker DNA with capillary electrophoresis, the process of loading DNA samples into gel capillaries and sending an electrical current through them. The current causes DNA molecules to travel through the gel, the smaller the DNA molecule the further away from the starting point they travel.

If you want to know what we use capillary electrophoresis for, read this publication.

Electric Blue capillary electrophoresis blue

Emerald Neurons

Emerald Neurons Hu iPSC neuronal cells

The network of neuronal cells in this image have been derived from human induced pluripotent stem cells and stained in green, highlighting the neuronal marker tubulin beta III. Our research into neurons looks to establish a model of Parkinson’s disease, and test the potential neuroprotective effects of tobacco-derived compounds.

Here’s an overview of our research presentation on neuroprotective effects.


Protein Junctions

In between these cells of a 3D human organotypic bronchial cell culture resides the protein ZO-1, stained in red. The protein is expressed in tight junctions; seals between cells that form a permeability barrier. The intact red trails mean that there’s no cell damage. In cases of cell/tissue damage, the tight junctions would not be visible.

This publication highlights 3D cell culture analysis.

Organotypic lung cells

Pale to Pink

Tobacco flowers

Believe it or not tobacco plants don't just produce leaves, they create a beautiful color palette of flowers. Our scientists are investigating flower diversity, starting with 'grandparents' that had pale or dark pink petals and cross-breeding those plants to produce offspring with the colors you see in the image.

If you want to know more about flowering tobacco plants, you can read this study.


Bronchial Bloom

This picture highlights a slide of primary human bronchial cells - from the surface of the windpipe. The bright greens and reds in this image are created by staining for P63 and CD151 respectively. Why are we highlighting these cells? Because studying them gives us deeper knowledge of lung physiology - better understanding of their structure, function, and how they react to various stimuli.

Read more about our cell culture studies here.


Luminous Spheres

These strange glowing orbs are human liver cell spheroids. But what are spheroids? They're a collection of cells used to mimic an organ. In our in vitro research we've developed lung/liver-on-a-chip technology for pre-clinical research. With further development, spheroids could potentially help supplement animal testing.

Click here to read more about organ-on-chip technology.


Nasal Housekeeping

This row of 3D human organotypic cells comes from nasal epithelium (inside a nose) made up of ciliated cells (which are topped with hair-like structures), goblet cells (which produce mucus), and basal cells (stem cells that can differentiate into other specialized cells). The flecks of red show the RNA expression of a gene called Hs-PPIB; a housekeeping gene.

To find out how and why we study nasal cells, click here.

Nasal Housekeeping

Science is Beautiful is a project aimed at revealing some of the most beautiful aspects of the science we do at PMI. We’re proud of the 430+ world-class scientists and engineers working with us, state-of-the-art technologies we use, and the beauty of the science we do each day. If these images have piqued your interest, be sure to stay tuned on PMIScience.com and follow us on social media.


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