Aurele Taieb

Prolongation of composite tissue allograft survival by immature recipient dendritic cells pulsed with donor antigen and transient low-dose immunosuppression.

Background: Composite tissue allograft transplantation is limited by risks of long-term immunosuppression. The authors investigated whether short-term immunosuppression combined with recipient immature dendritic cells pulsed with donor antigens promotes composite tissue allograft survival. Methods: Orthotopic hind-limb transplants were performed (day 0) from Wistar-Furth (RT1u) to Lewis (RT1l) rats. Recipient dendritic cells were propagated from bone marrow with granulocyte-macrophage colony-stimulating factor (bone marrow–derived dendritic cells) and pulsed with or without donor splenic cell lysate. Recipients were as follows: group I, control; group II, cyclosporine (10 mg/kg/day, days 0 through 6, intraperitoneally); group III, antilymphocyte serum plus cyclosporine (days −4 and +1, intraperitoneally); and groups IV and V, cyclosporine plus antilymphocyte serum, combined with 7 × 106 untreated or donor cell lysate-pulsed bone marrow–derived dendritic cells (days +7 and +14, intravenously), respectively. Epidermolysis/desquamation of donor skin defined rejection. Mixed leukocyte reaction determined recipient T-cell reactivity to donor. Tissue samples were obtained at 3 weeks and on the day of rejection. Groups comprised six or seven rats. Results: Donor alloantigen-pulsed bone marrow–derived dendritic cells (group V) significantly prolonged median composite tissue allograft survival time (32.0 days) compared with groups II (18.0 days, p = 0.0012), III (22.5 days, p = 0.0043), and IV (26.5 days, p = 0.0043). Splenic T cells in group V exhibited hyporesponsiveness to donor alloantigen in mixed leukocyte reaction. Interestingly, the graft muscle component in the bone marrow–derived dendritic cell–treated group (group V) showed significant reduction in mononuclear cell infiltration relative to group II (p = 0.0317). Conclusions: Donor alloantigen–pulsed recipient bone marrow–derived dendritic cells combined with transient T-cell–directed immunosuppression significantly prolonged composite tissue allograft survival across a full major histocompatibility complex barrier. This may represent the basis for a novel, clinically applicable strategy to promote composite tissue allograft survival with reduced systemic immunosuppression.

Long-term durability of tendon arthroplasty with excision of the trapezium in stage 1 osteoarthritis of the thumb CMC joint.

Basal joint arthritis of the thumb is commonly treated surgically. Although the results are good, there is still controversy regarding the treatment of young people with low radiographic stages of disease. Our purpose was to evaluate the durability of a tendon arthroplasty procedure in this population. Thirty patients aged 55 years or under, with early stage arthritis, were evaluated. Eight patients were available for long-term (average 86 months) follow-up. No deterioration in the strength and mobility of the operated thumbs in the long-term was found. There was a significant increase in tip pinch strength between short- and long-term follow-up evaluations. This study supports the durability of this surgery in younger patients, potentially reducing the need for multiple surgeries.

Mycobacterium monacense: A Mycobacterial Pathogen That Causes Infection of the Hand

We present a report of a diabetic patient with an infection of his left thumb and thenar eminence. Standard cultures of drainage and tissue biopsy were unrevealing. The infection progressed despite empiric antibacterial agent therapy and multiple debridements. Two intraoperative tissue biopsies revealed a yellow-pigmented, rapidly growing Mycobacterial nontuberculous species. The organism was identified as Mycobacterium monacense, a newly described species. The patient was cured with a 6-week course of clarithromycin and levofloxacin.