The genus Acinetobacter comprises extremely resistant gram-negative bacteria, which have developed resistance against almost all available antibiotics.


Actinomycetes are gram-positive bacteria, which are commonly found in nature. They produce interesting natural products, which are the basis of many of the antibiotics developed so far.

Adaptive immune response

The adaptive immune response is mediated by lymphocytes. Its hallmarks are a high specificity for distinct antigens and an immunological memory.

Adoptive immunotherapy

Adoptive immunotherapy is a new approach, partly still under development, to treat cancer and viral infections.


AIDS (Acquired Immune Deficiency Syndrome) is a weakness of the immune system caused by infection with the human immunodeficiency virus (HIV).


Amidochelocardin is a broad-spectrum antibiotic.

Anopheles mosquito

The Anopheles mosquito is a biting midge, which can transmit malaria.

Antibiotic resistance

Antibiotic resistance is a bacterial defense mechanism against antibiotics. It can rapidly spread from one bacterium to another. This makes antibiotics increasingly ineffective.

Antibiotic Stewardship

Antibiotic Stewardship encompasses measures aiming at a more rational way of prescribing antibiotics.


Antibodies are proteins that are generated in vertebrates in response to certain substances (antigens). They are an important part of the immune system.