Recent advances in surgical strategies and liver transplantation for hepatoblastoma

Hepatoblastoma (HB) is the most common malignant liver tumor in children. Although the development of treatment strategies with advances in chemotherapy has greatly improved the prognosis of HB, surgical resection and liver transplantation still play a vital role in the treatment of HB. In recent years, technological innovations have led to the development of new surgical approaches for HB. In this review, we describe the latest research on the surgical management of HB, including new imaging technologies, minimally invasive approaches, and the application of associating liver partition portal vein ligation for staged hepatectomy. We also discuss the current role of liver transplantation, use of ante-situm or ex-situ liver resection with auto-transplantation, and management of metastatic HB.

Factors predicting surgical difficulties in congenital biliary dilatation in pediatric patients

BACKGROUND

The effects of disease classification and the patient's preoperative condition on the difficulty of performing a laparotomy for pediatric congenital biliary dilatation (CBD) have not been fully elucidated.

METHODS

The present study retrospectively analyzed 46 pediatric CBD laparotomies performed at the study center between March 2010 and December 2021 and predictors of operative time. The patients were separated into a short operative time group (SOT) (≤ 360 min, n = 27) and a long operative time group (LOT) (> 360 min, n = 19).

RESULTS

The preoperative AST and ALT values were higher, and the bile duct anastomosis diameter was larger, in the LOT. Correlation analysis demonstrated that the maximum cyst diameter, preoperative neutrophil-to-lymphocyte ratio, AST, ALT, AMY, and bile duct anastomosis diameter correlated positively with operative time. Multivariate analysis identified the maximal cyst diameter, preoperative AST, and bile duct anastomosis diameter as significant factors affecting surgical time. Postoperatively, intrapancreatic stones and paralytic ileus were observed in one patient each in the SOT, and mild bile leakage was observed in one patient in the LOT.

CONCLUSIONS

The maximum cyst diameter, preoperative AST, and bile duct anastomosis diameter have the potential to predict the difficulty of performing a pediatric CBD laparotomy.

Natural Sulfur Compounds, Allyl Isothiocyanate and Diallyl Disulfide, Promote Cis to Trans Isomerization of Fatty Acid Esters during Heat Treatment

The effects of allyl isothiocyanate (AITC) and diallyl disulfide (DADS), widely found in edible vegetables, on thermal isomerization of unsaturated fatty acid esters (oleic acid methyl ester [OA-ME], linoleic acid methyl ester [LA-ME], and eicosapentaenoic acid ethyl ester [EPA-EE]) were investigated. Although heating with AITC and DADS significantly promoted cis to trans isomerization of all fatty acid esters, the isomerization trends varied greatly depending on the type of fatty acid. Specifically, AITC promoted thermal isomerization of OA-ME and LA-ME more efficiently than DADS; however, an opposite result was obtained for EPA-EE. For example, when OA-ME was heated at 180°C for 1 h with 1.0 equivalent of AITC and DADS, its trans isomer ratios reached 29.0 ± 7.1 and 7.6 ± 0.6%, respectively, and when EPA-EE was heated under the same conditions, its trans isomer ratios reached 4.2 ± 0.4 and 8.6 ± 0.2%, respectively. These results indicate that isothiocyanates and polysulfides would promote the formation of trans fatty acids in food processing under heating conditions.

Rapid in vitro assessment of the immunogenicity potential of engineered antibody therapeutics through detection of CD4+ T cell interleukin-2 secretion

Therapeutic antibodies sometimes elicit anti-drug antibodies (ADAs) that can affect efficacy and safety. Engineered antibodies that contain artificial amino acid sequences are potentially highly immunogenic, but this is currently difficult to predict. Therefore, it is important to efficiently assess immunogenicity during the development of complex antibody-based formats. Here, we present an in vitro peripheral blood mononuclear cell-based assay that can be used to assess immunogenicity potential within 3 days. This method involves examining the frequency and function of interleukin (IL)-2-secreting CD4+ T cells induced by therapeutic antibodies. IL-2-secreting CD4+ T cells seem to be functionally relevant to the immunogenic potential due to their proliferative activity and the expression of several cytokines. The rates of the donors responding to low and high immunogenic proteins, mAb1, and keyhole limpet hemocyanin were 1.3% and 93.5%, respectively. Seven antibodies with known rates of immunogenicity (etanercept, emicizumab, abciximab, romosozumab, blosozumab, humanized anti-human A33 antibody, and bococizumab) induced responses in 1.9%, 3.8%, 6.4%, 10.0%, 29.2%, 43.8%, and 89.5% of donors, respectively. These data are comparable with ADA incidences in clinical settings. Our results show that this assay can contribute to the swift assessment and mechanistic understanding of the immunogenicity of therapeutic antibodies.

Preclinical in vitro evaluation of immune suppression induced by GYM329, Fc-engineered sweeping antibody

Fc-engineering is commonly used to improve the therapeutic potency of antibody (Ab) treatments. Because FcγRIIb is the only inhibitory FcγR that contains an immunoreceptor tyrosine-based inhibition motif (ITIM), Fc-engineered Abs with enhanced binding affinity to FcγRIIb might provide immune suppression in clinical contexts. GYM329 is an anti-latent myostatin Fc-engineered Ab with increased affinity to FcγRIIb which is expected to improve muscle strength in patients with muscular disorders. Cross-linking of FcγRIIb by immune complex (IC) results in phosphorylation of ITIM to inhibit immune activation and apoptosis in B cells. We examined whether the IC of Fc-engineered Abs with enhanced binding affinity to FcγRIIb causes phosphorylation of ITIM or B cell apoptosis using GYM329 and its Fc variant Abs in human and cynomolgus-monkey (cyno) immune cells in vitro. IC of GYM329 with enhanced binding affinity to human FcγRIIb (×5) induced neither ITIM phosphorylation nor B cell apoptosis. As for GYM329, FcγRIIb should work as an endocytic receptor of small IC to sweep latent myostatin, so it is preferable that GYM329 induces neither ITIM phosphorylation nor B cell apoptosis to prevent immune suppression. In contrast, IC of myo-HuCy2b, the Ab with enhanced binding affinity to human FcγRIIb (×4), induced ITIM phosphorylation and B cell apoptosis. The result of the present study demonstrated that Fc-engineered Abs with similar binding affinity to FcγRIIb had different effects. Thus, it is important to also investigate FcγR-mediated immune functions other than binding to fully understand the biological effects of Fc-engineered Abs.

Appropriate pore size for bone formation potential of porous collagen type I-based recombinant peptide

Introduction

In this study, we developed porous medium cross-linked recombinant collagen peptide (mRCP) with two different ranges of interconnected pore sizes, Small-mRCP (S-mRCP) with a range of 100–300 μm and Large-mRCP (L-mRCP) with a range of 200–500 μm, to compare the effect of pore size on bone regeneration in a calvarial bone defect.

Methods

Calvarial bone defects were created in Sprague–Dawley rats through a surgical procedure. The rats were divided into 2 groups: S-mRCP implanted group and L-mRCP implanted group. The newly formed bone volume and bone mineral density (BMD) was evaluated by micro-computed tomography (micro-CT) immediately after implantation and at 1, 2, 3, and 4 weeks after implantation. In addition, histological analyses were carried out with hematoxylin and eosin (H&E) staining at 4 weeks after implantation to measure the newly formed bone area between each group in the entire defect, as well as the central side, the two peripheral sides (right and left), the periosteal (top) side and the dura matter (bottom) side of the defect.

Results

Micro-CT analysis showed no significant differences in the amount of bone volume between the S-mRCP and L-mRCP implanted groups at 1, 2, 3 and 4 weeks after implantation. BMD was equivalent to that of the adjacent native calvaria bone at 4 weeks after implantation. H&E images showed that the newly formed bone area in the entire defect was significantly larger in the S-mRCP implanted group than in the L-mRCP implanted group. Furthermore, the amount of newly formed bone area in all sides of the defect was significantly more in the S-mRCP implanted group than in the L-mRCP implanted group.

Conclusion

These results indicate that the smaller pore size range of 100–300 μm is appropriate for mRCP in bone regeneration.

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This study confirmed the regenerative potential of mRCP as novel bone substitute.

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mRCP with 2 different interconnected pores sizes have been developed.

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The smaller pore size range of 100–300 μm was optimal for calvarial bone regeneration.

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The slower absorption rate of smaller pore size mRCP influenced its effectiveness.

Simulated slide tracheoplasty for congenital tracheal stenosis using three-dimensional printed models

PURPOSE

The slide tracheoplasty (STP) is the standard treatment for severe congenital tracheal stenosis (CTS). Understanding the features of the tracheal stenosis in each case and choosing an appropriate incision design are very important for successfully executing the procedure. The present study aimed to evaluate the advantages of three-dimensional (3D) printed models of the trachea for improving CTS.

METHODS

Three-D tracheal models were created using computed tomography (CT) data from ten patients undergoing STP for CTS. Simulated surgery was performed using the hollow models after reinforcing with them with a coating of gum spray. Clinical outcomes, including patient survival, postoperative surgical interventions, and time required for STP, were compared with the corresponding values in the last ten patients before the introduction of 3D model simulations.

RESULTS

All ten patients for whom simulated surgery using a 3D tracheal model were conducted achieved good airway patency after their STP. The surgeons reported feeling that the 3D model simulations were highly effective although there was no significant difference in the clinical outcomes of the groups with or without simulated STP. The models were useful not only for surgical planning but also for sharing important information among the multidisciplinary team and the patients' family.

CONCLUSION

Our experience using 3D tracheal models demonstrated several features enabling improvement in the surgical treatment of CTS.

Study protocol for periodontal tissue regeneration with a mixture of autologous adipose-derived stem cells and platelet rich plasma: A multicenter, randomized, open-label clinical trial

Introduction

Adipose-derived stem cells (ASCs) secrete various growth factors to promote wound healing and to regenerate various tissues, such as bone, cartilage, and fat tissue. Subcutaneous adipose tissue is a considerable cell source in clinical practice and can be collected relatively easily and safely under local anesthesia. Moreover, platelet-rich plasma (PRP), a plasma component containing many platelets purified by centrifuging the collected blood, also promotes wound healing. PRP can be easily gelled and is therefore attracting attention as a scaffolding material for transplanted cells. The usefulness of a mixture of ASCs and PRP for periodontal tissue regeneration has been in vitro demonstrated in our previous study. The aim of this study is to present the protocol of translation of tissue regeneration with ASCs and PRP into practical use, evaluating its efficacy.

Methods

This study is a multicenter, randomized, open-label comparative clinical trial. Fifteen patients will be randomly assigned to the treatment with mixture of ASCs and PRP or enamel matrix derivate administration into periodontal tissue defects. Increase in height of new alveolar bone in the transplanted area will be evaluated. The evaluation will be performed using dental radiographs after 36 weeks of transplantation. Occurrence of adverse events will be evaluated as secondary outcome.

Results

This clinical study was initiated after meeting the regulations to be complied with, including ethical review and regulatory notifications.

Conclusions

If effective, this cell therapy using autologous mesenchymal stem cells can represent a useful medical technology for regeneration of periodontal defects.

Effect of Roasting Degree on Major Coffee Compounds: A Comparative Study between Coffee Beans with and without Supercritical CO2 Decaffeination Treatment

Coffee is a beverage that is consumed worldwide, and the demand for decaffeinated coffee has increased in recent years. This study aimed to investigate the effect of roasting conditions on the concentration of physiologically active compounds in coffee beans with and without supercritical CO₂ decaffeination treatment. Decaffeination treatment markedly reduced caffeine concentration and slightly reduced trigonelline concentration in the coffee beans, whereas the concentrations of chlorogenic acids (chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid) were largely unchanged. Roasting was performed using a hot-air coffee roaster machine and the coffee beans were treated at different peak temperatures (125-250℃), different hold times at the peak temperature (120-240 s), and different temperature increase times to reach the peak temperature (60-180 s). Roasting conditions such as long hold and long temperature rise times at high temperatures (≥ 225℃) significantly degraded coffee compounds except for caffeine, with similar degradation rates between non-decaffeinated and decaffeinated coffee beans. In contrast, the L* value of decaffeinated coffee decreased with less thermal history compared to that of non-decaffeinated coffee. This allowed for the complete roasting of decaffeinated coffee with a lower thermal history compared to those of non-decaffeinated counterparts, suppressing the degradation of several coffee compounds. For example, comparing the similar L* values between coffee beans with and without decaffeination treatment, it was found that the former tended to contain more chlorogenic acid. Generally, decaffeination results in the loss of physiologically active compounds along with caffeine, which is a major concern. However, this study showed that appropriate control of decaffeination and roasting conditions can limit the degradation of several valuable coffee compounds, such as trigonelline and chlorogenic acid.

High-temperature Supercritical CO2 Extraction of Lycopene from Tomato Powder for Enhancing Z-Isomerization and Recovery of Lycopene

This study aimed to investigate the effect of extraction conditions (temperature, pressure, and entrainer content) on the total Z-isomer ratio and recovery of lycopene in the extracts obtained after supercritical CO₂ (SC-CO₂) extraction of lycopene from tomato powder, with a particular focus on high-temperature conditions (≥ 80°C). The results showed that high-temperature SC-CO₂ extraction promoted the thermal isomerization of lycopene in a temperature-dependent manner up to 120℃. For example, when lycopene extraction was carried out at 80, 100, 120, and 140°C and a pressure of 30 MPa with an entrainer, ethanol, for 180 min, the total Z-isomer ratios obtained were 25.0, 57.2, 67.2, and 67.0%, respectively. The entrainer content also affected the Z-isomer ratio of lycopene, but the pressure had little effect. Interestingly, when SC-CO₂ extraction was performed under high-temperature conditions (≥ 100°C), the extraction efficiency of lycopene was dramatically improved, e.g., when lycopene was extracted at 80, 100, 120, and 140°C under the same other conditions as above, the recovery rates of lycopene were 4.6, 28.5, 79.9, 84.8%, respectively. In general, SC-CO₂ extraction of fat-soluble components is performed at temperatures in the range of 40-80°C because the SC-CO₂ density decreases with increasing temperature, and thus, their solubility (extraction efficiency) decreases. However, our results showed that the lycopene recovery increased in a temperature-dependent manner, which might be due to the solubility enhancement associated with thermal Z-isomerization of lycopene (i.e., lycopene Z-isomers have greater solubility than the naturally occurring all-E-isomer). The high-temperature SC-CO₂ extraction of lycopene from tomato materials not only enhances the Z-isomer ratio of lycopene in the resulting extracts but also improves lycopene recovery. This new finding will greatly contribute to the value addition and cost reduction of natural lycopene sources obtained by SC-CO₂ extraction.

Extraction of Fucoxanthin Isomers from the Edible Brown Seaweed Undaria pinnatifida Using Supercritical CO2: Effects of Extraction Conditions on Isomerization and Recovery of Fucoxanthin

Fucoxanthin, a characteristic carotenoid found in brown seaweeds, has been reported to exert beneficial biological activities, including antiobesity and anticancer activities Moreover, the Z-isomers of this compound potentially have greater bioavailability and biological activities than the naturally predominant all-E-isomer. Therefore, the consumption of Z-isomer-rich fucoxanthin through daily meals and dietary supplements may have beneficial effects. In this study, we aimed to investigate the effects of different extraction conditions on the Z-isomer ratio and recovery of fucoxanthin obtained from Undaria pinnatifida using supercritical CO2 (SC-CO2), particularly focusing on the high-temperature conditions that enhance thermal Z-isomerization. High-temperature SC-CO2 extraction at ≥ 120°C was found to enhance the thermal isomerization of fucoxanthin. For example, when the extraction was performed at 40, 80, 120, and 160°C and 30 MPa for 30 min with a co-solvent (ethanol), the total Z-isomer ratios were 11.7, 11.5, 18.7, and 26.5%, respectively. Furthermore, the high-temperature extraction significantly improved fucoxanthin recovery under high-pressure (≥ 30 MPa) conditions in the presence of the co-solvent. For example, when fucoxanthin was extracted at 40, 80, 120, and 160°C under the same conditions as above, the recoveries were 17.5, 20.6, 30.7, and 29.5%, respectively. Hence, the high-temperature SC-CO2 extraction of fucoxanthin from U. pinnatifida would not only enhance health benefits of fucoxanthin via the Z-isomerization but also improve the productivity. Moreover, the use of non-toxic CO2 and a low-toxicity organic solvent (ethanol) ensures that the final fucoxanthin product is safe for consumption. The Z-isomer-rich fucoxanthin obtained using this method is accordingly considered to have potential for use as a dietary supplement.

M-CSFR expression in the embryonal component of hepatoblastoma and cell-to-cell interaction between macrophages and hepatoblastoma

Tumor-associated macrophages (TAMs) have protumor functions in various cancers. However, their significance in hepatoblastoma, the most common liver tumor in children, remains unclear. The aim of this study was to explore the potential roles of TAMs in hepatoblastoma. Immunohistochemical analysis revealed that the density of CD204-positive TAMs was significantly higher in the embryonal component than in other histological subtypes of hepatoblastoma. An in vitro co-culture study with Huh6 cells and human monocyte-derived macrophages (HMDMs) showed that macrophage-colony-stimulating factor receptor (M-CSFR) was strongly up-regulated in the Huh6 cells that were directly co-cultured with HMDMs. The expressions of M-CSFR ligands (interleukin-34 and M-CSF) were also increased by co-culture with HMDMs. The proliferation of HepG2 cells (another hepatoblastoma cell line expressing M-CSFR) was inhibited by an M-CSFR inhibitor. M-CSFR was found to be highly expressed in the embryonal component and in recurrent lesions. The number of CD204-positive macrophages was also higher in the M-CSFR-positive areas than in the M-CSFR-negative areas. Thus, M-CSFR expression appeared to be induced by cell-cell contact with macrophages in hepatoblastoma cells, and M-CSFR inhibitor is potentially effective against M-CSFR-positive hepatoblastoma, especially recurrent cases.

Surgical Outcomes of Domino Liver Transplantation Using Grafts From Living Donors With Familial Amyloid Polyneuropathy

Domino liver transplantation (DLT) using grafts from donors with familial amyloid polyneuropathy is an acceptable procedure for expanding the donor pool. The vascular and biliary reconstructions in living donor DLT (LDDLT) are technically demanding, and data on the short-term and long-term surgical outcomes of domino donors and recipients in LDDLT are limited. In this study, we identified 25 domino recipients from our liver transplantation program (1999-2018), analyzed the vascular and biliary reconstructions performed, and evaluated the surgical outcomes, including graft survival. Piggyback technique was adopted in all 25 domino donors. The only surgical complication in domino donors was hepatic vein (HV) stenosis with an incidence rate of 4%. In 22 domino recipients, right HV and middle/left HV were reconstructed separately. A total of 10 recipients had 2 arteries anastomosed, and 18 underwent duct-to-duct biliary anastomosis. HV stenosis and biliary stricture had incidence rates of 8% and 24%, respectively, in the recipients, but none of them developed hepatic artery thrombosis. The 1-year and 5-year graft survival rates were 100% each in the domino donors, and 84.0% and 67.3% in the domino recipients, respectively. In conclusion, LDDLT has acceptable outcomes without increasing the operative risk in donors despite the demanding surgical technique involved.

In vivo imaging with two-photon microscopy to assess the tumor-selective binding of an anti-CD137 switch antibody

STA551, a novel anti-CD137 switch antibody, binds to CD137 in an extracellular ATP concentration-dependent manner. Although STA551 is assumed to show higher target binding in tumor tissues than in normal tissues, quantitative detection of the target binding of the switch antibody in vivo is technically challenging. In this study, we investigated the target binding of STA551 in vivo using intravital imaging with two-photon microscopy. Tumor-bearing human CD137 knock-in mice were intravenously administered fluorescently labeled antibodies. Flow cytometry analysis of antibody-binding cells and intravital imaging using two-photon microscopy were conducted. Higher CD137 expression in tumor than in spleen tissues was detected by flow cytometry analysis, and T cells and NK cells were the major CD137-expressing cells. In the intravital imaging experiment, conventional and switch anti-CD137 antibodies showed binding in tumors. However, in the spleen, the fluorescence of the switch antibody was much weaker than that of the conventional anti-CD137 antibody and comparable with that of the isotype control. In conclusion, we were able to assess switch antibody biodistribution in vivo through intravital imaging with two-photon microscopy. These results suggest that the tumor-selective binding of STA551 leads to a wide therapeutic window and potent antitumor efficacy without systemic immune activation.

Multiple assessment of molars with hypercementosis lost due to periodontitis using X-ray micro-computed tomography, electron microprobe analysis, and histological sections

This article aimed to achieve a better understanding of cementum hyperplasia in the maxillary second molars lost due to periodontitis. Six maxillary second molars with hypercementosis were measured for the mineral concentration using micro-computed tomography and calcium element distributions using electron microprobe analysis. Calcium was distributed throughout the cementum, although the mineral concentration differed based on the cementum depth. The hyperplastic cementum was of the extrinsic fiber-rich cellular mixed stratified type. These results have implications for future studies aiming to diagnose hypercementosis. Further studies are needed to investigate the composition of the cementum matrix.

IL-34 in hepatoblastoma cells potentially promote tumor progression via autocrine and paracrine mechanisms

Hepatoblastoma is the most common pediatric liver tumor, but little research has been done on the role of macrophages in hepatoblastoma. The purpose of this study was to gain insight into potential roles for macrophages in hepatoblastoma. Paraffin‐embedded specimens from 56 patients who underwent surgical resection were examined with immunohistochemical staining for the macrophage‐specific markers, Iba1 and CD163. Significant differences were seen among histological subtypes. Significantly increased numbers of macrophages were detected in embryonal components compared to fetal components in the mixed epithelial type. In vitro studies using human monocyte‐derived macrophages and two hepatoblastoma cell lines (HepG2 and Huh6) were performed. Conditioned medium from these cell lines induced increased CD163 expression in macrophages. Direct co‐culture with macrophages induced tumor cell proliferation via induction of protumor cytokine secretion from macrophages. Direct co‐culture with macrophages also induced interleukin (IL)‐34 overexpression by Huh6 cells via Brd4 signaling. IL‐34 overexpression promoted tumor cell proliferation and chemoresistance. High IL‐34 and Brd4 expression was detected in embryonal components, which have potentially higher proliferation activity than fetal components. In conclusion, IL‐34 expression in embryonal components may induce macrophage chemotaxis in a paracrine manner, and tumor cell proliferation and chemoresistance in an autocrine manner. IL‐34 is a potential therapeutic target for hepatoblastoma.

Intellectual development of patients with biliary atresia who underwent living donor liver transplantation in infancy

BACKGROUND

The impact of pediatric liver transplantation on intellectual development has yet to be determined. We investigated the intellectual outcomes of school-aged patients after living donor liver transplantation for biliary atresia in infancy.

METHODS

The Wechsler Intelligence Scale for Children-fourth edition test was administered to 20 patients who survived [Formula: see text] 5 years after living donor liver transplantation. Borderline full scale intelligence quotient was defined as ≤ 85. Pre-, peri-, and postoperative data were compared between patients with > 85 and ≤ 85 to identify predictive factors of borderline performance.

RESULTS

The one-sample t test demonstrated that the mean full scale intelligence quotient of patients after transplantation for biliary atresia was significantly lower than that of the general population (91.8 vs. 100.0, p = 0.026) and 7 (35%) were classified as intellectual borderline functioning. Multivariable logistic regression models were unable to identify any factors predictive of full scale intelligence quotients of ≤ 85.

CONCLUSION

This is the first study to indicate that the mean full scale intelligence quotient among school-aged patients who underwent living donor liver transplantation for biliary atresia in infancy is significantly lower than that of the general population.

Application of E/Z-Isomerization Technology for Enhancing Processing Efficiency, Health-Promoting Effects, and Usability of Carotenoids: A Review and Future Perspectives

Carotenoids are naturally occurring pigments whose presence in the diet is beneficial to human health. Moreover, they have a wide range of applications in the food, cosmetic, and animal feed industries. As carotenoids contain multiple conjugated double bonds in the molecule, a large number of geometric (E/Z, trans/cis) isomers are theoretically possible. In general, (all-E)-carotenoids are the most predominant geometric isomer in nature, and they have high crystallinity and low solubility in various mediums, resulting in their low processing efficiency and bioavailability. Technological developments for improving the processing efficiency and bioavailability of carotenoids utilizing the Z-isomerization have recently been gaining traction. Namely, Z-isomerization of carotenoids induces a significant change in their physicochemical properties (e.g., solubility and crystallinity), leading to improved processing efficiency and bioavailability as well as several biological activities. For the practical use of isomerization technology for carotenoids, the development of efficient isomerization methods and an acute understanding of the changes in biological activity are required. This review highlights the recent advancements in various conventional and unconventional methods for carotenoid isomerization, such as thermal treatment, light irradiation, microwave irradiation, and catalytic treatment, as well as environment-friendly isomerization methods. Current progress in the improvement of processing efficiency and biological activity utilizing isomerization technology and an application development of carotenoid Z-isomers for the feed industry are also described. In addition, future research challenges in the context of carotenoid isomerization have been elaborated upon.

Directly recruited GATA6 + peritoneal cavity macrophages contribute to the repair of intestinal serosal injury

Recruitment of bone marrow derived monocytes via bloodstream and their subsequent conversion to CX3CR1⁺ macrophages in response to intestinal injury is dependent on CCR2, Nr4a1, and the microbiome. This process is critical for proper tissue repair; however, GATA6⁺ peritoneal cavity macrophages might represent an alternative, more readily available source of mature and functional myeloid cells at the damaged intestinal locations. Here we show, using spinning-disk confocal microscopy, that large F4/80^hiGATA6⁺ peritoneal cavity macrophages promptly accumulate at damaged intestinal sites upon intestinal thermal injury and upon dextran sodium sulfate induced colitis in mice via a direct route from the peritoneal cavity. In contrast to bloodstream derived monocytes/macrophages, cavity macrophages do not depend on CCR2, Nr4a1 or the microbiome for recruitment, but rather on the ATP-release and exposed hyaluronan at the site of injury. They participate in the removal of necrotic cells, revascularization and collagen deposition and thus resolution of tissue damage. In summary, peritoneal cavity macrophages represent a rapid alternative route of intestinal tissue repair to traditional monocyte-derived macrophages.

Upon intestinal injury, bone marrow derived monocytes are recruited to the damaged site through the bloodstream. Authors here show that peritoneal cavity macrophages directly migrate to the damaged intestine in an ATP and hyaluronan dependent manner, and participate in the restoration of tissue integrity.