C3bi-binding protein on Candida albicans: temperature-dependent expression and relationship to human complement receptor type 3.

We investigated in detail the previously described capacity of pseudohyphae of Candida albicans to bind C3-coated particles. We show that the expression of the C3bi receptor of C. albicans was dependent upon the growth temperature of the fungi. C. albicans grown at 30 degrees C bound strongly to EAC1423bi, whereas those cells grown at 38.5 degrees C were completely devoid of this capacity. The molecule responsible for the attachment of EAC1423bi was heat labile and trypsin sensitive. Several, but not all, monoclonal antibodies to the alpha-chain of human complement receptor type 3 (CR3) stained C. albicans, and this reactivity was expressed in parallel with the capacity of C. albicans to bind EAC1423bi, i.e., both were dependent on the growth temperature of the fungi and were trypsin sensitive. In contrast to CR3, the binding of EAC1423bi to C. albicans did not require the presence of divalent cations. Rabbit immunoglobulin G antibodies directed against C. albicans inhibited the binding of EAC1423bi to C. albicans but not to human CR3. These inhibiting IgG antibodies recognized antigens expressed on the surface of pseudohyphae but not those of yeast cells. OKM-1, a monoclonal antibody to human CR3 inhibited the attachment of EAC1423bi to CR3 and also to C. albicans. OKM-1 precipitated a 130-kilodalton band from solubilized 125I-labeled C. albicans. We conclude that the complement receptors on C. albicans and human CR3 were antigenically related but not identical and that they differed in their functional characteristics.     

Secretion of vascular endothelial growth factor/vascular permeability factor from human luteinized granulosa cells is human chorionic gonadotrophin dependent

Vascularization is a prominent event during corpus luteum formation, providing low density lipoproteins for steroid biosynthesis and enabling transport of secreted steroids. The process of vascularization is controlled by specific regulators. Vascular endothelial growth factor (VEGF), otherwise named vascular permeability factor (VPF), induces endothelial cell proliferation as well as angiogenesis in vivo and increases capillary permeability. Here we report the expression of VEGF/VPF mRNA by cultured human luteinized granulosa cells (GC) for at least 10 days. Without HCG VEGF/VPF expression declined after day 4 and by day 10 was reduced to approximately 30% of the value at day 4. However, after culture in the presence of 1 U/ml human chorionic gonadotrophin (HCG), expression of VEGF/VPF mRNA by GC was four times greater than control experiments by day 10, and increased 100% from day 4 to day 10. Simultaneously, HCG supplementation increased VEGF/VPF secretion by GC. Medium VEGF/VPF on day 3 was 13 pM without and 11 pM with HCG. Medium VEGF/VPF on day 10 was 6 pM without HCG and 29 pM with HCG. These results suggest that vascularization of the corpus luteum is induced by HCG-mediated effects of VEGF/VPF.      

Biological resurfacing of the knee: a review of surgical management

Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.     

RENAL TRANSPLANTATION – AN EARLY EXPERIENCE

Renal transplant (RT) is now a therapy of choice for end stage renal disease (ESRD). The Nephrology Unit, Asvini started functioning in Dec 90 and to date 1298 sittings of hemodialysis have been given to 45 patients. Of these, 35 were in ESRD and 11 patients underwent renal transplantation at this hospital during the period Jan 91 – Dec 93. One patient expired after 18 months of transplantation due to infection. Early experience in screening patients for RT, use of immunosuppression, management of rejection episodes and protocol are presented with special emphasis on its relevance to the Armed Forces.KEY WORDS: Transplantation, Renal Failure, Immunosuppression, Rejection