Interleukin-4 inhibits indoleamine 2,3-dioxygenase expression in human monocytes

Indoleamine 2,3-dioxygenase (IDO), a flavin-dependent enzyme that catalyzes the conversion of tryptophan to kynurenine, is induced in peripheral blood mononuclear cells by interferon-gamma (IFN gamma). Interleukin-4 (IL-4) is a cytokine that modulates the functional properties of monocytes/macrophages, and we investigated the effects of IL-4 on IDO. We showed that IL-4 inhibited the induction of IDO mRNA and IDO activity by IFN gamma in human monocytes. The inhibitory effect was evident with as little as 2 U/mL of IL-4. These results provide the first evidence that a cytokine can provide a negative signal for IDO expression and that IL-4 can influence the catabolism of tryptophan.     

TCR V alpha chain expression influences reactivity to the hapten TNP

We have recently demonstrated a remarkable selection of in vitro cultivated, TNP-specific polyclonal T cell lines for the expression of a TCR beta chain encoded by the V beta 8.2 gene. The goal of the present study was to analyse V alpha usage in V beta 8.2 T cells responsive to TNP, using TNP-specific T cell lines derived from three common strains of mice, as well as from V beta 8.2 transgenic mice. Results indicate that in vitro TNP stimulation of T cells from TNP- immune mice results in significant skewing of V alpha usage among responding V beta 8.2+ T cells, with overexpression observed for V alpha 3.2 and V alpha 8. These results indicate that V alpha expression influences recognition of TNP by T cells, and suggest that the hapten TNP might be recognized like typical peptide antigens by combinatorial TCR alpha and beta contact sites.      

Feasibility and limits of split liver transplantation from pediatric donors: an italian multicenter experience

OBJECTIVE: To report the results of a multicenter experience of split liver transplantation (SLT) with pediatric donors. SUMMARY BACKGROUND DATA: There are no reports in the literature regarding pediatric liver splitting; further; the use of donors weighing <40 kg for SLT is currently not recommended. METHODS: From 1997 to 2004, 43 conventional split liver procedures from donors aged <15 years were performed. Nineteen donors weighing < or =40 kg and 24 weighing >40 kg were used. Dimensional matching was based on donor-to-recipient weight ratio (DRWR) for left lateral segment (LLS) and on estimated graft-to-recipient weight ratio (eGRWR) for extended right grafts (ERG). In 3 cases, no recipient was found for an ERG. The celiac trunk was retained with the LLS in all but 1 case. Forty LLSs were transplanted into 39 children, while 39 ERGs were transplanted into 11 children and 28 adults. RESULTS: Two-year patient and graft survival rates were not significantly different between recipients of donors < or =40 kg and >40 kg, between pediatric and adult recipients, and between recipients of LLSs and ERGs. Vascular complication rates were 12% in the < or =40 kg donor group and 6% in the >40 kg donor group (P = not significant). There were no differences in the incidence of other complications. Donor ICU stay >3 days and the use of an interposition arterial graft were associated with an increased risk of graft loss and arterial complications, respectively. CONCLUSIONS: Splitting of pediatric liver grafts is an effective strategy to increase organ availability, but a cautious evaluation of the use of donors < or =40 kg is necessary. Prolonged donor ICU stay is associated with poorer outcomes. The maintenance of the celiac trunk with LLS does not seem detrimental for right-sided grafts, whereas the use of interposition grafts for arterial reconstruction should be avoided.     

Results of intestinal and multivisceral transplantation in adult patients: Italian experience

PURPOSE: We report our experience with intestinal and multivisceral transplantation in Italy. METHODS: We performed 23 adult isolated intestinal transplants and seven multivisceral ones, three with liver, between December 2000 and June 2005. Indications for transplantation were loss of venous access (n = 14), recurrent sepsis (n = 10), and electrolyte-fluid imbalance (n = 6), 14 of whom also presented with total parenteral nutrition (TPN)-related liver dysfunction. Immunosuppression was based on induction agents like daclizumab (followed by tacrolimus and steroids) in the first period; alemtuzumab or thymoglobulin (with tacrolimus) in a second period after 2002. RESULTS: The mean follow-up was 742 +/- 550 days. Three-year patient actuarial survival rate was 88% for intestinal transplants and 42% for multivisceral (P = .015). Three-year graft actuarial survival rate was 73% for intestinal patients and 42.8% for multivisceral (P = .1). Graft loss was mainly due to rejection (57%). Complications were mainly represented by bacterial infections (92% of patients), relaparotomies (82%), and rejections (72%). Full bowel function without any parenteral nutrition or intravenous fluid support was achieved in 60% of recipients with functioning bowel including 95% on a regular diet. One patient underwent abdominal wall transplantation as well. DISCUSSION AND CONCLUSION: Intestinal transplantation has achieved high rates of patient and graft survival with even longer follow-up. Early referral of patients, especially in cases of TPN-liver disease, is mandatory to obtain good outcomes and avoid high mortality rates on the transplant waiting list. Immunosuppressive management remains the key factor to increase the success rate.     

Successful treatment of rhinomaxillary form of mucormycosis infection after liver transplantation: a case report

Mucormycosis is a rare opportunistic infection, usually associated with immunocompromised states. Several conditions such as hematologic malignancy (leukemia, lymphoma, myeloma), solid organ transplantation, diabetes mellitus, corticosteroid therapy, or chemotherapy predispose patients to infection. The aim of this study was to present a single case of mucor infection after 900 consecutive liver transplantations. Rhinomaxillary mucormycosis must be suspected in a transplant recipient showing fever, maxillary swelling, and edema. This condition can be successfully treated with early diagnosis and a combination of aggressive surgery and antifungal therapy.