Immune Evasion by Borrelia burgdorferi – With Special Reference to CD38-mediated Chemotaxis of Neutrophils and Dendritic Cells

Lyme borreliosis is a tick-transmitted infection caused by the spirochete bacterium Borrelia burgdorferi sensu lato. The tick injects bacteria into host skin, where a first line defence, mainly the complement system, neutrophils, dendritic cells and macrophages are ready to attack foreign intruders. However, in the case of Lyme borreliosis, the original immune response in the skin is untypically mild among bacterial infections. A further untypical feature is the ability of B. burgdorferi to disseminate to distant organs, where, in some patients, symptoms appear after years after the original infection. This study aimed at uncovering some of the immune evasion mechanisms utilized by B. burgdorferi against the complement system, neutrophils and dendritic cells. B. burgdorferi was shown to inhibit chemotaxis of human neutrophils towards nformyl- methyl-leucyl-phenylalanine (fMLP). Outer surface protein B (OspB) of B. burgdorferi was shown to promote resistance to the attack of the complement system and neutrophil phagocytosis at low complement concentrations. B. burgdorferi was shown to inhibit migration of dendritic cells in vitro towards CCL19 and CCL21 and also in an in vivo model. This effect was shown to be due to the absence of CD38 on the borrelia-stimulated dendritic cell surface. A defect in p38 mitogen-activated-protein-kinase (p38) signaling was linked to defective CD38 expression. A defect in CD38 expression on B. burgdorferi-stimulated neutrophils was also observed. In this study, a number of novel immune evasion strategies utilized by B burgdorferi were chracterized. However, further studies are needed as other immune evasion mechanisms await to be uncovered.Siirretty Doriast

Lymphangiogenesis and Lymphangiogenic Growth Factors

Lymphedema is a progressive disease caused by damage to the lymphatic network. Recent development in the fields of preclinical growth factor research and lymphedema microsurgery promise new hope for lymphedema patients. In this article, we review the latest results on basic research and highlight the role of specific growth factors in normal lymphatic development and several disease states. Lymph node transfer, a new promising method in reconstructive lymphatic microsurgery, is also dependent on the lymphatic vascular regrowth and lymphangiogenic growth factors. We discuss the scientific basis of lymph node transfer and therapeutic potential of lymphangiogenic growth factors in the treatment of lymphedema.Peer reviewe

Pehmytkudospatti

English summar

Phase 1 Lymfactin (R) Study : Short-term Safety of Combined Adenoviral VEGF-C and Lymph Node Transfer Treatment for Upper Extremity Lymphedema

Objective: To study the safety and tolerability of Lymfactin (R) treatment combined with microvascular lymph node transfer surgery in patients with upper limb lymphedema. Background: Upper limb lymphedema is a common clinical challenge after breast cancer surgery and/or radiotherapy. Lymfactin (R) is an adenovirus type 5-based gene therapy involving expression of human vascular endothelial growth factor C (VEGF-C) in the damaged tissue. It aims to correct deficient lymphatic flow by promoting the growth and repair of lymphatic vessels. Methods: In Phase I, Lymfactin (R) was combined with microvascular lymph node transfer surgery to study the safety and tolerability of Lymfactin (R) and the biodistribution of the viral vector in patients with upper limb lymphedema. Results: Fifteen patients with breast cancer-associated secondary lymphedema of the upper arm were recruited between December 2016 and February 2018. Three patients received a lower dose (1 x 10(10)) and 12 a higher dose (1 x 10(11)) of viral particles, respectively. No dose-limiting toxicities were observed, and the study was completed with the pre-determined maximum dose. Commonly reported adverse events during the 12-month follow-up were common cold, fever, gastroenteritis, pain in the operation area, headache, muscle ache and elevated liver enzymes. Serious adverse events consisted of two erysipelas infections in the lymphedema arm (requiring hospitalization) and one hematoma of the flap donor site. Conclusions: After 12 months' follow-up, results indicate that Lymfactin (R) is well tolerated. The study continues with a 36-months efficacy and 5 years safety follow-up of the patients. The oncological safety aspects of Lymfactin (R) will require a longer follow-up period. (c) 2020 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Pub-lished by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/)Peer reviewe

Short duration of upper extremity lymphedema correlates with a favorable cytokine response after lymph node transfer surgery

Vascularized lymph node transfer surgery (VLNT) can provide benefit to lymphedema patients. Cytokines mayplaya role in the development oflymphedema and in the regeneration oflymphatic vessels after VLNT. Ourprimary aim was to investigate whether the VLNTpatients have a specific cytokine profile. Our secondary aim was to see whether the preoperative lymphedema or severity affects the postoperative cytokine response. Wound exudate was gathered from 18 patients undergoing VLNT on the first and sixth postoperative day (POD). The concentrations of IL-10, TNF-alpha, TGF-beta 1 and VEGF-C were analyzed using enzyme-inked immune-sorbent assays. A general score was generated to assess the benefit ofthe surgery. The changes in cytokine concentrations (1(st) POD-6th POD) were correlated with the pre- andpostoperative lymphedema related factors. A shorter duration oflymphedema preoperatively correlated with an increase in the concentration of IL-10 and TNF-beta during the first six PODs (IL-10: r=0.495, p=0.051; TNF-alpha: p=0.006) and a decrease in the concentration of 7VF-111 (r= p=0.020). The increase ofthe concentration of TNF-alpha during the first six PODs also correlated with a greater total general score (r=0.775, p=0.005) and hence indicated a better response to the surgery. The patients with a shorter duration oflymphedema preoperatively had a more favorable cytokine response during the first six PODs after VLNT

Anti-inflammatory effects of flap and lymph node transfer

Background: Transfer of healthy tissue is commonly used in the treatment of complicated wounds and in reconstruction of tissue defects. Recently, microvascular lymph node transfer (LN) has been used to improve the lymphatic function in lymphedema patients. To elucidate the biological effects of flap transfer (with and without lymph nodes), we have studied the postoperative production of proinflammatory, anti-inflammatory, prolymphangiogenic and antilymphangiogenic cytokines, and growth factors (interleukin 1 alpha [IL-1 alpha], IL-1 beta, tumor necrosis factor alpha [TNF-alpha], IL-10, transforming growth factor beta 1 [TGF-beta 1], IL-4 and IL-13, and vascular endothelial growth factor C [VEGF-C] and VEGF-D) in postoperative wound exudate samples. Methods: Axillary wound exudate samples were analyzed from four patient groups: axillary lymph node dissection (ALND), microvascular breast reconstruction (BR), LN, and combined LN and BR (LN-BR). Results: The concentration of proinflammatory cytokines was low in all the flap transfer groups as opposed to the ALND group, which showed an extensive proinflammatory response. The level of anti-inflammatory and antifibrotic cytokine IL-10 was increased in the LN-BR group samples compared with the ALND and BR groups. In the LN and LN-BR groups, the cytokine profile showed an anti-inflammatory response. Conclusions: Transfer of healthy tissue hinders the proinflammatory response after surgery, which may explain the beneficial effects of flap transfer in various patient groups. In addition, flap transfer with lymph nodes seems to also promote an antifibrotic effect. The clinical effects of LN in lymphedema patients may be mediated by the increased production of prolymphangiogenic growth factor (VEGF-C) and antifibrotic cytokine (IL-10). (C) 2015 Elsevier Inc. All rights reserved.Peer reviewe

Donor-site safety in microvascular lymph node transfer for breast cancer-related lymphedema using reverse lymphatic mapping : A prospective study

Background: Vascularized lymph node transfer (VLNT) is one option among other surgical treatments in the management of breast cancer-related lymphedema (BCRL). The cause of concern regarding VLNT harvested from the groin has been the potential development of secondary lower-extremity lymphedema. This study explored the risks associated with donor-site morbidity following groin VLNT, with or without concomitant breast reconstruction. Method: The cohort comprised data from the Lymfactin® Phase I and II trials, conducted from 2016 to 2019, that used perioperative reverse lymphatic mapping. The volume of the lower extremities was measured preoperatively and at 3, 6, and 12 months postoperative, and the adverse events were documented during study visits. Results: Altogether, 51 women with a mean age of 55.5 years were recruited. The mean duration of BCRL was 31.8 months. Among these, 25 (49%) underwent VLNT (VLNT-group) and 26 (51%) underwent VLNT in combination with breast reconstruction (VLNT-BR group). The groups were similar in terms of age, (p = 0.766), BMI (p = 0.316), and duration of BCRL (p = 0.994). Across a period of one year, the volume difference between the lower extremities changed by 22.6 ml (range: −813 to 860.2 ml) (p = 0.067). None of the patients had lower-extremity volume difference exceeding 10% at the 12-month follow-up visit. The most frequent adverse events were postoperative pain (17.7%), wound healing issues (11.8%), and seroma formation (11.8%). Most adverse events (64.6%) were classified as minor. Conclusions: This prospective study demonstrated that groin VLNT with reverse lymphatic mapping appears safe and does not increase the risk of secondary donor-site lymphedema within one year postoperatively.Peer reviewe

CC chemokine ligand 2 (CCL2) stimulates aromatase gene expression in mammary adipose tissue

Obesity is a risk factor for postmenopausal breast cancer. Obesity-related inflammation upregulates aromatase expression, the rate-limiting enzyme for estrogen synthesis, in breast adipose tissue (BAT), increasing estrogen production and cancer risk. The regulation of aromatase gene (CYP19A1) in BAT is complex, and the mechanisms linking obesity and aromatase dysregulation are not fully understood. An obesity-associated factor that could regulate aromatase is the CC chemokine ligand (CCL) 2, a pro-inflammatory factor that also activates signaling pathways implicated in CYP19A1 transcription. By using human primary breast adipose stromal cells (ASCs) and aromatase reporter (hARO-Luc) mouse mammary adipose explants, we demonstrated that CCL2 enhances the glucocorticoid-mediated CYP19A1 transcription. The potential mechanism involves the activation of PI.4 via ERK1/2 pathway. We also showed that CCL2 contributes to the pro-inflammatory milieu and aromatase expression in obesity, evidenced by increased expression of CCL2 and CYP19A1 in mammary tissues from obese hARO-Luc mice, and subcutaneous adipose tissue from obese women. In summary, our results indicate that postmenopausal obesity may promote CCL2 production in BAT, leading to exacerbation of the menopause-related inflammatory state and further stimulation of local aromatase and estrogens. These results provide new insights into the regulation of aromatase and may aid in finding approaches to prevent breast cancer

Phase 1 LymfactinⓇ Study: Short-term Safety of Combined Adenoviral VEGF-C and Lymph Node Transfer Treatment for Upper Extremity Lymphedema

Objective: To study the safety and tolerability of LymfactinⓇ treatment combined with microvascular lymph node transfer surgery in patients with upper limb lymphedema.Background: Upper limb lymphedema is a common clinical challenge after breast cancer surgery and/or radiotherapy. LymfactinⓇ is an adenovirus type 5–based gene therapy involving expression of human vascular endothelial growth factor C (VEGF-C) in the damaged tissue. It aims to correct deficient lymphatic flow by promoting the growth and repair of lymphatic vessels.Methods: In Phase I, LymfactinⓇ was combined with microvascular lymph node transfer surgery to study the safety and tolerability of LymfactinⓇ and the biodistribution of the viral vector in patients with upper limb lymphedema.Results: Fifteen patients with breast cancer–associated secondary lymphedema of the upper arm were recruited between December 2016 and February 2018. Three patients received a lower dose (1 × 1010) and 12 a higher dose (1 × 1011) of viral particles, respectively. No dose-limiting toxicities were observed, and the study was completed with the pre-determined maximum dose. Commonly reported adverse events during the 12-month follow-up were common cold, fever, gastroenteritis, pain in the operation area, headache, muscle ache and elevated liver enzymes. Serious adverse events consisted of two erysipelas infections in the lymphedema arm (requiring hospitalization) and one hematoma of the flap donor site.Conclusions: After 12 months’ follow-up, results indicate that LymfactinⓇ is well tolerated. The study continues with a 36-months efficacy and 5 years safety follow-up of the patients. The oncological safety aspects of LymfactinⓇ will require a longer follow-up period.</p

Low TGF-β1 in Wound Exudate Predicts Surgical Site Infection After Axillary Lymph Node Dissection

PurposeSurgical site infection (SSI) after axillary lymph node dissection (ALND) for breast cancer increases morbidity and delays the onset of adjuvant treatment. Only a few studies have investigated the feasibility of wound exudate analysis in SSI prediction. This study assessed changes in cytokine levels in postsurgical wound exudate after ALND and examined their predictive value for the early diagnosis of SSI.MethodsAn observational prospective pilot study was conducted in 47 patients with breast cancer undergoing ALND. Wound exudate samples were collected on the first and sixth postoperative days (POD). Interleukin (IL)-1α, IL-1β, IL-4, IL-10, IL-13, tumor necrosis factor alpha (TNF-α), transforming growth factor beta1 (TGF-β1) and vascular endothelial growth factor (VEGF) C and D levels were measured by immunoassay. Patients were followed to detect SSI.ResultsSSI was diagnosed in 8/47 (17.0%) patients. Four SSI patients were hospitalized and treated with intravenous antibiotics. The concentration of TGF-β1 in wound exudate was significantly lower on POD#1 in the SSI group compared to the no SSI group (p=0.008). The receiving operator characteristics (ROC) curve for TGF-β1 showed an area under curve of 0.773 (p=0.0149) indicating good diagnostic potential. On POD#6, the concentration of TGF-β1 remained significantly lower (p=0.043) and the concentrations of IL-10 (p=0.000) and IL-1β (0.004) significantly higher in the SSI group compared to the no SSI group.ConclusionTo our knowledge, this is the first study suggesting a predictive role of wound exudate TGF-β1 levels for SSI. Our results suggest that the risk for SSI can be detected already on POD#1 and that the assessment of TGF-β1 levels in the wound exudate after ALND can provide a usefull method for the early detection of SSI. The key findings of this pilot study warrant verification in a larger patient population.</p