Archives: Comics

Plasma cell; B cell; shooting antibodies with a sling

Plasma cells, are a specialized type of B cells that produce large volumes of antibodies. This B cell here is using those antibodies to neutralize an invading flu virus that has entered the body.

Adoptive cell transfer of CD45.2 T lymphocytes to new host CD45.1 mouse host

Adoptive cell transfer refers to the transfer of cells into an organism, which could be a patient or in the case of this cartoon, a mouse. This is a very common technique used in immunology research to understand how the cells behave.

Adoptive Cell Transfer in Immunology Research

Typically, the cells that are being transfer have a different marker than the cells in the host. After being transferred to the new hosts, this marker allows the cells to be distinguished from the host cells. In this cartoon here the marker is CD45.1 and the marker of the host cells is CD45.2. Depending on the application, cells can also be labeled with a dye before being transferred so you can trace them back. An example of such a dye, that is also used to trace cell proliferation, is Carboxyfluorescein succinimidyl ester (CFSE).

If you are curious on some of the applications adoptive cell transfers in immunology research read this article Utilization of CD45.1 as a Marker of Donor Leukocytes in Recipient CD45.2 Mice in a Bone-Marrow Transfer Chimeric Experiment by Biocompare.

Adoptive Cell Transfer for Treating Disease

More recently, adoptive cell transfers have also been used to treat disease in humans. As an example, cells are taken out of a patient, the cells are then ‘re-educated’ and transferred back into the same patient. These now ‘educated’ or ‘activated’ cells can go ahead and perform their function to cure disease. You can read more about how this is applied to treat cancer in the article Adoptive cell transfer as personalized immunotherapy for human cancer published by Science Magazine.

 

 

Cartoon Host-Pathogen Arm Wrestling

This cartoon is showing the battle between a leukocyte and a bacterium. Who will win?

The interactions between the host cell and a pathogen trying to invade an organism, commonly referred to as host-pathogen interactions, are very important to understand disease. Each pathogen might have a unique way of interacting with their host and the host may react in different ways to different pathogens. This is a battle that goes on inside our bodies when we get sick, we may not see it but we feel it.

Here is more information on host-pathogen interactions.

cartoon of monocyte-dericed dendritic cell

This monocyte turned into a dendritic cell (DC) and doesn’t even know how it happened!
Many researchers isolate monocytes and then derive them into DCs to do studies on these cells. It is a common method followed by people studying DCs that need to generate some cells for their experiments.

In case you are interested in generating monocyte-derived dendritic cells (Mo-DCs) from human cells, below are some protocols you can follow.

Protocols

 

Cartoon of Dendritic Cell Presenting Antigen on MHC to T Cell

The dendritic cell (DC) is presenting an antigen to a T cell but the T cell doesn’t recognize it. This is making the DC kind of sad.

In this case the DC is presenting the antigen on an MHC-I molecule and it is showing to a CD8 T cells. However, the T cell will recognize and respond to the antigen, only when if it is a specific antigen and it is bound to a particular MHC molecule. This process is called MHC restriction.

To learn more about antigen presentation and MHC restriction check out these links:

  • Video: MHC Class I Processing
  • Video: MHC Class II Processing
  • Poster: Nature Immunology Antigen Processing
  • Funny Comic by Pedromics: Presentation of the Antigen
  • Immunobiology Book: The major histocompatibility complex and its functions
  • Figure 5.16 T-cell recognition of antigens is MHC restricted

    The antigen-specific T-cell receptor (TCR) recognizes a complex of antigenic peptide and MHC. One consequence of this is that a T cell specific for peptide x and a particular MHC allele, MHCa (left panel), will not recognize the complex of peptide x with a different MHC allele, MHCb (center panel), or the complex of peptide y with MHCa (right panel). The co-recognition of peptide and MHC molecule is known as MHC restriction because the MHC molecule is said to restrict the ability of the T cell to recognize antigen. This restriction may either result from direct contact between MHC molecule and T-cell receptor or be an indirect effect of MHC polymorphism on the peptides that bind or on their bound conformation.

Cartoon & biology illustration of epithelial cells held together by tight junctions

Epithelial cells form a layer that line several organs of the body providing a barrier to the outside world. In other words, the epithelial cells help to protect or enclose the organs.

Epithelial cells are held together by tight junctions, which form a virtually impermeable barrier to prevent leakage of fluid (including molecules and ions) across the cell layer, so materials must actually enter the cells in order to pass through the tissue.

 

References:

Tight Junctions article by Wikipedia

Cell-Cell Adhesion and Communication on Molecular Cell Biology. 4th edition.

Cell Junctions on Molecular Biology of the Cell. 4th edition.

Cartoon of granulocytes: neutrophil, basophil and eosinophil

These feisty granulocytes will defeat any bacteria, fungus or parasite that wants to mess with them. Check out the full blog post on granulocytes to lear more about each one of these cells.