Absorbable subcuticular staples versus suture for caesarean section closure: a randomised clinical trial.

OBJECTIVE: To compare outcomes of efficiency, safety, patient, and surgeon satisfaction between absorbable subcuticular staples and subcuticular suture for caesarean section skin closure. DESIGN: A prospective, randomised, non-blinded, parallel-group trial. SETTING: Mayo Clinic Family Birth Center in Rochester, MN, USA. POPULATION: At least 18 years old and 24 weeks' gestation, undergoing caesarean section. Exclusion criteria were body mass index >50, chorioamnionitis, intrauterine fetal death, and multifetal gestation. METHODS: Patients were stratified by prior caesarean section, body mass index, and surgeon level and randomised to absorbable subcuticular staples or subcuticular suture. Electronic medical records and surveys were used. MAIN OUTCOME MEASURES: Primary outcomes were total operating time, from incision start to close. Secondary outcomes included subcuticular skin closure time, patient and surgeon satisfaction, percutaneous injuries, pain (analgesic use), cosmesis, and wound complications. RESULTS: Of 220 randomised patients, 206 were included in the final analysis (103 per group). Baseline characteristics were similar. The primary outcome of total operative time was not significantly different between groups [54.0 (44.9-63.6) versus 58.0 (50.4-68.2) minutes, P = 0.053]. The subcuticular staple group had shorter subcuticular skin closure time [median 2.6 (1.8-4.0) versus 8.5 (6.2-10.5) minutes, P < 0.001]. There were no differences in analgesic use, wound complications, cosmesis or patient satisfaction. One needlestick injury occurred with suture. Surgeons were more likely to recommend (97% versus 85%, P = 0.004) and use (98% versus 82%, P < 0.001) absorbable subcuticular staples. CONCLUSION: For caesarean section skin closure, absorbable subcuticular staples did not result in significantly different total operative times compared with sutures. Analgesic use, wound complications, and cosmesis were comparable. Patient and surgeon satisfaction were high with both methods. TWEETABLE ABSTRACT: Absorbable subcuticular staples associated with a similar total operative time compared with suture.

Endogenous IL-2 production by natural killer cells maintains cytotoxic and proliferative capacity following retroviral-mediated gene transfer.

Interleukin (IL)-2 therapy given at tolerable doses is insufficient to induce maximum activation of natural killer (NK) cells. We recently demonstrated that NK cells expanded in vivo can be maximally activated by short-term ex vivo incubation with 1000 U/mL IL-2. However, IL-2 withdrawal, which would occur with reinfusion, may lead to a rapid loss of cell viability and function. We hypothesized that retroviral transduction could provide an endogenous source of IL-2 to maintain NK function as measured by proliferation and cytotoxicity. Enriched NK cells were transduced with supernatants containing an MFG-based retrovirus designed to express murine IL-2 cDNA. Several supernatant transduction strategies were evaluated. NK cells were initially cultured in 1000 U/mL of huIL2 for 7-8 days, harvested, and replated prior to transduction (4 hours at 37degrees C); this proved insufficient to sustain NK proliferation or maintain cytotoxicity after exogenous human IL-2 (huIL-2) withdrawal. An alternative transduction procedure using phosphate-depleted medium, centrifugation, and transduction for 16 hours at 32degrees C was then evaluated. NK cells transduced under these conditions maintained significant NK proliferation in the absence of exogenous IL-2 compared with sham-transduced controls. Two consecutive daily transductions resulted in less proliferation, suggesting that several exposures to retroviral supernatant may inhibit subsequent NK proliferation. Cytotoxicity of the transduced NK cells against K562 and Raji was maintained under these conditions without exogenous IL-2. Sham-transduced NK cells produced 8.3+/-2.6 U/mL of murine IL-2 (muIL-2) by ELISA (background) after 7 days without exogenous IL-2. In contrast, 109+/-23 U/mL muIL-2 was produced by NK cells transduced with supernatant from the MFG/muIL-2 producer line. These experiments demonstrate that NK cells can be successfully transduced with retroviruses and induced to express sufficient IL-2 to maintain their proliferative and cytotoxic functions. Transduction of IL-2 genes into NK cells may offer advantages over exogenous IL-2 administration in maintaining maximum function for use in antitumor immunotherapy.

Low dose subcutaneous interleukin-2 after autologous transplantation generates sustained in vivo natural killer cell activity.

Autologous transplantation can induce extended remission in some patients with advanced breast cancer and lymphoma yet nearly 80% and 50%, respectively, will ultimately relapse. In vitro studies suggest that activated natural killer cells (NK) mediate lytic activity against breast cancer and lymphoma cell lines. Therefore, immunotherapy with interleukin-2 (IL-2, Amgen) to activate NK may improve long-term disease-free survival when administered in a post-transplant minimal residual disease setting. To determine the feasibility of administering IL-2 and activation of NK post-transplant, twelve patients (6 breast cancer, 6 lymphoma) were enrolled on a phase I dose escalation study after autologous transplantation (median day + 94, range 50-166). IL-2 was self administered at 0.25 x 10(6) (n = 6) or 0.5 x 10(6) (n = 6) U/m2/day subcutaneously for 84 consecutive days. The best tolerated dose was 0.25 x 10(6) U/m2/day (75% of planned doses given vs. 48% at the higher dose). Dose limiting toxicity occurred in 6 patients (n = 2 at 0.25 x 10(6) U/m2/day, n = 4 at 0.5 x 10(6) U/m2/day) consisting of decreased performance status (n = 2), thrombocytopenia (n = 3, 1 at the lower dose), and mild neutropenia (n = 1 at the lower dose). However, all symptoms resolved within a week following discontinuation of IL-2 and no patient required hospitalization. Circulating soluble IL-2 receptor levels were significantly increased in all patients receiving IL-2. Patients receiving at least 28 days of IL-2 exhibited a greater than 10-fold increment in circulating CD56+bright/CD3- NK. Furthermore, lytic function was increased against NK resistant targets, MCF-7 (breast cancer), and Raji (lymphoma). In vivo IL-2 primed NK cells obtained by lymphapheresis were activated in large-scale ex vivo incubation in high dose IL-2 (1,000 U/mL) at high cell density (10 x 10(6)/mL), in gas permeable bags, and using serum-free media. NK lytic function against MCF-7 and Raji targets was further enhanced. We conclude that low dose subcutaneous IL-2 based immunotherapy is feasible, relatively safe, can be administered in an outpatient setting and hypothesize that additional ex vivo incubation in IL-2 may be used to generate NK cells with potent antitumor effects in vivo.