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mRNA (multicoloured strand) is decoded in a ribosome to produce an aminoacid chain, that folds into a protein (red). tRNA (dark violet) molecules carry single aminoacids that are incoporated into the growing chain.

Passive immunization with nanobodies: two neutralizing nanobodies that target the receptor-binding domain of the SARS-CoV-2 spike protein. Nanobodies can have a highly increased neutralizing activity compared to antibodies. Source: PDB entry: 7b18. Koenig, P.A. et al. (2021) Science 371

Dendritic cells processes stabilised SARS-CoV-2 spike proteins to produce antigens out of them and to present them subsequently to T-cells . Source: PDB entry 7e7b.

A cytokine storm is a physiological reaction in which the innate immune system causes an uncontrolled and excessive release of pro-inflammatory signaling molecules called cytokines.

1: Complement C1, 2: fibrinogen, 3: von Willebrand factor, 4: ferritin, 5: HDL. 6: immunoglobulin G, 7: immunoglobulin M, 8: albumin carrying fatty acids, 9: LDL.

Noroviruses are transmitted from person to peron and via contaminated water and food.

Dust mites feed on moulds (green) and organic detritus. Their feces (greenish spots) induce allergenic reactions. The glossy brown spheres are their eggs.

Tapeworms are a species of parasitic flatworms. They live in the digestive tracts of vertebrates.

Two different therapeutic monclonal antibodies bind at different antigenic sites of the coronavirus spike protein. They can confer synergistic protection agains SARS-CoV-2. Source: PDB entry 7cwn. Yao; H. et al.; (2021) Cell Res 31: 25-36.

Natural killer cells are a type of lymphocytes which destroy cancer cells and other altered cells releasing cytotoxic granules.

Dust mites eat flakes of shed human skin and other organic detritus. Their feces are the inducers of allergenic reactions.

The mRNA contained in the COVID-19 mRNA vaccine is translated in a ribosome into a modified version of the viral spike protein (red). Afterwards, the human cell produces antigens out of the spike protein,. These antigens induce a strong immune response to the virus.

Amyloid plaques on axons of neurons affected by Alzheimer's disease

Dust mites eat flakes of shed human skin and other organic detritus. Their feces are the inducers of allergenic reactions.

Neurons with amyloid plaques (right side) compared to healthy neurons (left). Amyloid plaques accumulate outside neurons. Amyloid plaques are characteristic features of Alzheimer's disease. They lead to a degeneration of the affected neurons, that are destroyed through the activity of microglia cells.

Main mutation sites of the UK variant B.1.1.7. The spike protein (red) is bound to the angiotensin converting enzyme 2 (blue). Source: PDB entry 6cs2.

White fat cells contain a large lipid droplet (yellow) and a nucleus (red) located in the periphery.

Polyps are a growth of tissue occurring on the lining of the colon or rectum.Untreated colorectal polyps can develop into colorectal cancer.

Multiple sclerosis is a demyelinating disease in which the insulating covers of nerve cells are damaged. Microglia cells (orange) attack the oligodendrocytes that form the insulating myelin sheath around neuron axons, leading to the destruction of the myelin sheath and to the loss of nerve function.

After being cleaved by the gamma and beta secretases the amyloid beta peptide, which has about 40 amino acid residues, leaves the membrane, changes shape and aggregates into long fibrils. These fibrils form dense plaques on nerve cells, which are involved in Alzheimer's disease.

Tapeworms are a species of parasitic flatworms. They live in the digestive tracts of vertebrates. The scolex (head) attachess to the intestine of the host, the hooks and suckers aid in the attachment.

The LDL-receptor (red) is a membrane protein found in almost every human cell. It binds to the apoprotein B100 from LDL-particles and mediates their internalization (endocytosis) in the cell. This occurs in almost all cells but mainly in the liver where it removes about 70 % of LDL from the circulation.

An activated T helper cell segregates the cytokines IL-4, IL-5, IL-6, IL-9, IL-10 and IL-13, leading to B cell antibody class switching, activation of cytotoxic T cells, and maximazing the bactericidal activity of phagocytes such as macrophages. Source: PDB entries 2B8U, 3VA2, 1ALU, 2H24, 3BPO

Microglia are specialised macrophages that restrain the accumulation of ß-amyloid (plaques in orange). On the other side, once activated, they can have harmful influences in Alzheimer's disease, segregating inflammatory factors and mediating the engulfment of synapses.

C. auris causes candidiasis, an infection of the bloodstream, the central nervous system and internal organs. It has acquired multiple drug resistance.

Microglia are specialised macrophages that restrain the accumulation of ß-amyloid (plaques in orange). On the other side, once activated, they can have harmful influences in Alzheimer's disease, segregating inflammatory factors and mediating the engulfment of synapses.

Erythrocytes (red blood cells) are trapped within a fibrin mesh.

The opioid receptors display a role in modulating pain perception; opioid agonists are therefore potent analgesics. They appear mainly in the brain and spinal cord. The endogenous opioids are enkephalin, dynorphin, endorphin and nociceptin.

Molecules of cell nucleus in the interphase. Nucleolus (the granular structure), DNA being transcripted to mRNA (pink) by the RNA polymerase (green), and several enzymes: the endonuclease (violet), the DNA ligase (yellow) and the DNA topoisomerase (magenta)

3d illustration of the ATP synthesis in a mitochondrion. ATP synthase couples ATP (red) synthesis from ADP and inorganic phosphate (orange) to a proton gradient (light points) created across the mitochondrial membrane during cellular respiration.

A segment of the colon free of any intestinal disease

Untreated colorectal polyps can develop into colorectal cancer

Approximate size comparison of a LDL (left) and a HDL (right) particle. The blue structure on the LDL particle ist the protein Apo B 100, while the green structure on the HDL particle is build up of a "belt" of Apo A proteins.

Two different therapeutic monoclonal antibodies bind at different antigenic sites of the coronavirus spike protein. They can confer synergistic protection against SARS-CoV-2.

Dendritic cells are antigen-presenting cells of the immune system. Their main function is to process antigen material and present it on the cell surface to the T cells of the immune system. They are messengers between the innate and the adaptive immune systems.

From left to right: the NMDA and AMPA receptors transport calcium cations into neurons after being activated by the neurotransmitter glutamate and the GABA receptor (right) transport chloride anions after the activation by gamma aminobutyrate. PDB entries: 6wht, 3kg2, 6d6u

Immune response to SARS-CoV-2: B-lymphocyte releases antibodies that bind to and mark coronaviruses. Hence, the viruses can't penetrate into their target cells and are engulfed and destroyed by a macrophage (cell in the background).

Pathological phosphorylation (yellow) of Tau proteins (red-orange) leads to disintegration of microtubuli in the neuron axon an aggregation of the tau proteins. The transport of synaptic vesicles (orange-violet spheres) is interrupted.

The binding of LDL particles to the LDL receptors mediates the endocytosis of the particles through clathrin coated vesicles, which a then processed in the inner cell.

A polyp which can turn into colon cancer. Such polyps are considered pre-cancerous. Almost all colorectal tumors start from adenomatous polyps

The Carboniferous is a geologic period extending from about 350 to 300 million years ago. In the carboniferous period a vast amount of coal beds were build all over the world.

A cytokine storm is a physiological reaction in which the innate immune system causes an uncontrolled and excessive release of pro-inflammatory signaling molecules called cytokines.

(left to right) Potassium channel (with potassium ions), delta-opioid receptor (with endorphin molecule), LDL receptor (with LDL particle in the background), acetylcholine receptor (with acetyl choline), histamine receptor (with histamine)

Tapeworms are a species of parasitic flatworms. They live in the digestive tracts of vertebrates.

Low-density lipoprotein (LDL) particles transport the water insoluble lipids like cholesterol, phospholipids, triglycerids and certain vitamins in blood plasma from the liver to other organs and tissues. A single LDL particle contains 3.000 to 6.000 fat molecules and a single apolipoprotein B molecule, a large protein (depicted in blue), building the surface with the phospholipids (depicted in orange with a blue cap) and cholesterol molecules (depicted in orange with a violet cap).

UV light can cause mutations in the DNA and induce skin cancer.

Binding of the coronavirus spike protein(red) to an ACE2 receptor (blue) on a human cell leads to the penetration of the virus in the cell, as depicted in the background.

The opioid and cannabinoid receptors are involved in pain-sensation, mood, appetite and memory. Agonists are potent analgesics: Endorphin (red) and tetrahidrocannabinol (green).

The ulcerative colitis is an inflammatory disease of the human bowel.

Heparin (yellow) binds to and activates antithrombin. Antithrombin is the most important inhibitor of coagulation proteases like thrombin. Activation of antithrombin has an anticoagulant effect. Source: PDB entry 3evj

Peptic ulcer or stomach ulcer, is a break in the lining of the stomach, first part of the small intestine, or occasionally the lower esophagus

A RNA polymerase (yeast) is composed of several proteins. It unwinds DNA strands (violet) and builds RNA (red) out of the nucleotides uridine, adenosine, cytlidine and guanosine monophosphate.

Coronaviruses coated with antibodies can't penetrate into their target cells and are engulfed and destroyed by a macrophage (cell in the background).

Natural killer cells are lymphocytes that target virus infected cells and tumor cells without deliberate immunization or activation. They play a critical role in the control of tumor growth and metastasis.

Cas9 uses CRISPR sequences to recognize and cleave specific strands of DNA. It is used as a specific and easy way to edit genes. Source: PDB entry 5b2r

Plasma cells produce and segregate antibodies. The antibodies mark pathogens for destruction by phagocytic cells, they coat key sites on pathogens necessary for infection, and they induce the complement cascade to react against antibody-bound pathogens.

Insulin (light orange) binding induces structural changes within the receptor, which activates a signal cascade leading to the transport of glucose (yellow) into the cell through glucose transporter proteins (red).

Alzheimer: Pathological phosphorylation (yellow) of Tau proteins (red-orange) by kinases (violett) leads to disintegration of microtubuli in the neuron axon an aggregation of the tau proteins. The transport of synaptic vesicles (orange-blue) is interrupted.

Crohn's disease is an inflammatory bowel disease, it causes abdominal pain, diarrhea and vomiting.

The spike protein (red) mediates the coronavirus entry into host cells. It binds to the angiotensin converting enzyme 2 (blue) through its S1 subunit and then fuses viral and host membranes through the S2 subunits. Source: PDB entry 6cs2