[Disorders of hematopoiesis in immunodeficiencies].

There is increasing experimental evidence for the influence of the immune system on the regulation of hematopoiesis. The question is how much information on the basic pathomechanisms we can gain when we study the disturbances of hematopoiesis observed in congenital and secondary immunodeficiencies. Frequently, there is a contradiction between in vitro results and in vivo observations. Only in some cases (e.g. the development of eosinophils), are experimental results supported by clinical observations. All concepts of regulation and influence of the immune system on hematopoiesis have to be measured against the disturbances seen in the patients.