Placental Localisation of Aspergillus Fumigatus In Bovine Mycotic Abortion: Enhancement of Spore Germination In Vitro By Foetal Tissue Extracts

Experimental candidosis in pregnant mice

“…To our knowledge, the stimulatory effect of murine or bovine placental extracts on the growth of Candida spp. has not yet been examined, but the present and former observations (9, 10) are suggestive of a favourable environment for fungal proliferation in the murine placenta (4, 19). While nutritional factors in the placenta may contribute to fungal proliferation, the susceptibility of this tissue may also in part be due to a temporary protection of blastospores against phagocytic leukocytes and T lymphocytes.…”

“…jiumigatus and aqueous extracts of bovine placental cotyledons enhance the in vitro growth of A . ,firmigutus and various genera of Mucorales (4, 19).…”

“…Only mice with a PAMP-1 concentration above 150 arbitrary units/ ml were considered to be pregnant (7). One hundred arbitrary units refers to the amount of PAMP-1 in a pool of sera from late pregnant (days [16][17][18][19]) mice (n = 84).…”

Rapid germination ofAspergillus fumigatusconidia in mouse kidneys and a kidney extract

“…The degree to which tissue extracts stimulated hyphal extension was assayed as described (16) in wells in Czapek Dox agar (5 ml) dispensed into 5 cm diam. glass petri dishes.…”

“…This localisation may be due to the presence of nutrients, or the physicochemical conditions required for the development of the pathogen or to the inability of the host's immune defences to prevent the establishment and expansion of infection (12). Mycelial growth ofAspergillusfumigatus localises in the placentae of pregnant sheep and cows challenged intravenously with conidia (5,8) and substances in an aqueous extract of the bovine placenta stimulate conidial germination in vitro (16). If conidia germinate more rapidly in the placenta than in other organs in vivo, the infection might quickly establish and overwhelm the local immune defences.…”