ABSTRACT
The mechanisms and aetiology underlying the development of premature ovarian insufficiency (POI) are poorly understood. However, the oocyte clearly has a role as demonstrated by the Double Mutant (DM) mouse model where ovarian dysfunction (6 weeks) is followed by POI (3 months) due to oocyte-specific deletion of complex and hybrid N- and O-glycans. The ovaries of DM mice contain more primary follicles (3a stage) accompanied by fewer developing follicles, indicating a block in follicle development. To investigate this block, we first analysed early follicle development in postnatal (8-day), pre-pubertal (3-week) and post-pubertal (6-week and 3-month) DM (C1galt1 F/F Mgat1 F/F:ZP3Cre) and Control (C1galt1 F/F Mgat1 F/F) mice. Second, we investigated if transplantation of DM ovaries into a "normal" endocrine environment would restore follicle development. Third, we determined if replacing DM ovarian somatic cells would rescue development of DM oocytes. At 3-week, DM primary 3a follicles contain large oocytes accompanied by early development of a second GC layer and increased GC proliferation. At 6-week, DM primary 3a follicles contain abnormally large oocytes, accompanied with decreased GC proliferation. Transplantation of DM ovaries into a 'normal' endocrine environment did not restore normal follicle development. However, replacing somatic cells by generating reaggregated ovaries (ROs) did enable follicle development to progress and thus highlighted intra-ovarian factors were responsible for the onset of POI in DM females. Thus, these studies demonstrate oocyte-initiated altered communication between GCs and oocytes results in abnormal primary follicles which fail to progress and leads to POI.
ABSTRACT
In mice and humans two distinct CD4+ helper T cells, known as Th1 and Th2 are identified. They are characterized by the different cytokine milleau they induce. The balance between Th1 and Th2 responses is thought to be decisive for the initiation and course of some autoimmune disorders, as well as for the outcome of infectious processes. In the present study the development of Candida alibcans infection in mice with adjuvant-induced arthritis was investigated. An impaired host resistance against C. alibcans in arthritic mice was registered when the inoculation was done during the early and the established phases of arthritis. In contrast, the slight elevation of the number of survivors was detected when the infection was induced at the peak of inflammation. These data correlated with the changes of serum TNF-alpha level and delayed type hypersensitivity (DTH) to C. alibcans.
