Human adipose tissue-derived stromal cells can differentiate into megakaryocytes and platelets by secreting endogenous thrombopoietin

Essentials Manufacturing platelets from a donor-independent source is highlighted in transfusion medicine. We examined the differentiation of adipose tissue-derived stromal cells (ASCs) into platelets. Endogenous thrombopoietin (TPO) induced ASCs differentiation into megakaryocytes and platelets. TPO secretion from ASCs was due to an interaction of transferrin with its receptor CD71.

SUMMARY

Background Ex vivo production of megakaryocytes (MKs) and platelets from a donor-independent source is currently of intense interest in transfusion medicine. Adipose tissue-derived stromal cells (ASCs) constitute an attractive candidate cell source, because inducing these cells into MK lineages requires no gene transfer and only endogenous transcription factors containing p45NF-E2/Maf, an MK-inducing factor. Objectives To examine whether ASCs differentiate into MK lineages by using endogenous thrombopoietin (TPO), a primary cytokine that drives MK lineages. Methods TPO levels were measured by quantitative real-time PCR and ELISA. To investigate the effects of endogenous TPO on MK and platelet production, surface marker expression and functions for platelets were analyzed in ASC-derived cells cultured in the presence or absence of recombinant TPO. Based on a screening test, the role of transferrin receptor CD71 in TPO production and MK differentiation was examined with anti-CD71 antibody, small interfering RNA (siRNA) against CD71 (siRNA-CD71), and CD71-positive/negative cells. Results ASCs secreted TPO during MK differentiation, and the endogenous TPO facilitated MK and platelet production from ASCs. TPO secretion from ASCs occurred in a transferrin-dependent manner. ASCs treated with anti-CD71 antibody or transfected with siRNA-CD71 produced markedly less TPO. The TPO levels and MK yield were significantly higher when CD71-positive ASCs were used than when CD71-negative ASCs were used. Conclusions CD71 might be an appropriate marker for MK progenitor cells among human ASCs, because of the higher capacity of CD71-positive cells to produce TPO and their ability to differentiate into MKs. These findings could help to establish an efficient method for platelet production.

Correction of coronal alignment correlates with reconstruction of joint height in unicompartmental knee arthroplasty

OBJECTIVES

Because there have been no standard methods to determine pre-operatively the thickness of resection of the proximal tibia in unicompartmental knee arthroplasty (UKA), information about the relationship between the change of limb alignment and the joint line elevation would be useful for pre-operative planning. The purpose of this study was to clarify the correlation between the change of limb alignment and the change of joint line height at the medial compartment after UKA.

METHODS

A consecutive series of 42 medial UKAs was reviewed retrospectively. These patients were assessed radiographically both pre- and post-operatively with standing anteroposterior radiographs. The thickness of bone resection at the proximal tibia and the distal femur was measured radiographically. The relationship between the change of femorotibial angle (δFTA) and the change of joint line height, was analysed.

RESULTS

The mean pre- and post-operative FTA was 180.5° (172.2° to 184.8°) and 175.0° (168.5° to 178.9°), respectively. The mean δFTA was 5.5° (2.3° to 10.1°). The joint line elevation of the tibia (JLET) was 4.4 mm (2.1 to 7.8). The δFTA was correlated with the JLET (correlation coefficient 0.494, p = 0.0009).

CONCLUSIONS

This study indicated that there is a significant correlation between the change of limb alignment and joint line elevation. This observation suggests that it is possible to know the requirement of elevation of the joint line to obtain the desired correction of limb alignment, and to predict the requirement of bone resection of the proximal tibia pre-operatively. Cite this article: Bone Joint Res 2015;4:128-133.

Correction of coronal alignment correlates with reconstruction of joint height in unicompartmental knee arthroplasty

Objectives

Because there have been no standard methods to determine pre-operatively the thickness of resection of the proximal tibia in unicompartmental knee arthroplasty (UKA), information about the relationship between the change of limb alignment and the joint line elevation would be useful for pre-operative planning. The purpose of this study was to clarify the correlation between the change of limb alignment and the change of joint line height at the medial compartment after UKA.

Methods

A consecutive series of 42 medial UKAs was reviewed retrospectively. These patients were assessed radiographically both pre- and post-operatively with standing anteroposterior radiographs. The thickness of bone resection at the proximal tibia and the distal femur was measured radiographically. The relationship between the change of femorotibial angle (δFTA) and the change of joint line height, was analysed.

Results

The mean pre- and post-operative FTA was 180.5° (172.2° to 184.8°) and 175.0° (168.5° to 178.9°), respectively. The mean δFTA was 5.5° (2.3° to 10.1°). The joint line elevation of the tibia (JLET) was 4.4 mm (2.1 to 7.8). The δFTA was correlated with the JLET (correlation coefficient 0.494, p = 0.0009).

Conclusions

This study indicated that there is a significant correlation between the change of limb alignment and joint line elevation. This observation suggests that it is possible to know the requirement of elevation of the joint line to obtain the desired correction of limb alignment, and to predict the requirement of bone resection of the proximal tibia pre-operatively. Cite this article: Bone Joint Res 2015;4:128–133

Antileukemia multifunctionality of CD4(+) T cells genetically engineered by HLA class I-restricted and WT1-specific T-cell receptor gene transfer

To develop gene-modified T-cell-based antileukemia adoptive immunotherapy, concomitant administration of CD4(+) and CD8(+) T cells that have been gene modified using identical HLA class I-restricted leukemia antigen-specific T-cell receptor (TCR) gene transfer has not yet been fully investigated. Here, using CD4(+) and CD8(+) T cells that had been gene modified with a retroviral vector expressing HLA-A*24:02-restricted and Wilms' tumor 1 (WT1)-specific TCR-α/β genes and siRNAs for endogenous TCRs (WT1-siTCR/CD4(+) T cells and WT1-siTCR/CD8(+) T cells), we examined the utility of this strategy. WT1-siTCR/CD4(+) T cells sufficiently recognized leukemia cells in an HLA class I-restricted manner and provided target-specific Th1 help for WT1-siTCR/CD8(+) T cells. By using a xenografted mouse model, we found that WT1-siTCR/CD4(+) T cells migrated to leukemia sites and subsequently attracted WT1-siTCR/CD8(+) T cells via chemotaxis. Therapy-oriented experiments revealed effective enhancement of leukemia suppression mediated by concomitant administration of WT1-siTCR/CD4(+) T cells and WT1-siTCR/CD8(+) T cells. Importantly, this augmented efficacy in the presence of WT1-siTCR/CD4(+) T cells was correlated with longer survival and enhanced formation of memory T cells by WT1-siTCR/CD8(+) T cells. Collectively, our experimental findings strongly suggest that this strategy would be clinically advantageous for the treatment of human leukemia.

Mechanism of action of newly developed vitamin D analogue

26,27-F6-1,25(OH)2D3 has a higher potency both in vivo and in vitro systems, and longer duration of action in vivo, instead of almost equal binding to 1,25(OH)2D3 receptor and comparatively short serum half-life. To date, the mechanism of higher action is not known, but using these analogues as a mirror we might be able to elucidate the mechanism of action or the metabolism of the kidney hormone, 1,25(OH)2D3.

Genetic diversity and population structure in native chicken populations from myanmar, Thailand and laos by using 102 indels markers

The genetic diversity of native chicken populations from Myanmar, Thailand, and Laos was examined by using 102 insertion and/or deletion (indels) markers. Most of the indels loci were polymorphic (71% to 96%), and the genetic variability was similar in all populations. The average observed heterozygosities (H_O) and expected heterozygosities (H_E) ranged from 0.205 to 0.263 and 0.239 to 0.381, respectively. The coefficients of genetic differentiation (Gst) for all cumulated populations was 0.125, and the Thai native chickens showed higher Gst (0.088) than Myanmar (0.041) and Laotian (0.024) populations. The pairwise Fst distances ranged from 0.144 to 0.308 among populations. A neighbor-joining (NJ) tree, using Nei’s genetic distance, revealed that Thai and Laotian native chicken populations were genetically close, while Myanmar native chickens were distant from the others. The native chickens from these three countries were thought to be descended from three different origins (K = 3) from STRUCTURE analysis. Genetic admixture was observed in Thai and Laotian native chickens, while admixture was absent in Myanmar native chickens.

Genetic Diversity of mtDNA D-loop Polymorphisms in Laotian Native Fowl Populations

Here, we studied the genetic diversity of native fowls in Laos by analyzing a mitochondrial DNA (mtDNA) sequence polymorphism. A 546-bp fragment of the mtDNA D-loop region was sequenced in 129 chickens from the areas of Vientiane, Luang Prabang and Pakse. In total, 29 haplotypes were identified and formed five clades. Haplotype diversity and nucleotide diversity of the native fowls in Laos were 0.85536±0.0172 and 0.010158±0.005555, respectively. Although the Laotian native fowls were distributed across five clades, most of them were clustered in two main clades (A and B), which were originated in China. The other haplotypes were contained in clades D, F, and I, which originated from continental southeast Asia. These results suggest that multiple maternal lineages were involved in the origin of domestic chicken in Laos. Moreover, there appear to be at least two maternal lineages, one from China and the other from the southeast Asian continent.

Reversible electric-field control of magnetization at oxide interfaces

Electric-field control of magnetism has remained a major challenge which would greatly impact data storage technology. Although progress in this direction has been recently achieved, reversible magnetization switching by an electric field requires the assistance of a bias magnetic field. Here we take advantage of the novel electronic phenomena emerging at interfaces between correlated oxides and demonstrate reversible, voltage-driven magnetization switching without magnetic field. Sandwiching a non-superconducting cuprate between two manganese oxide layers, we find a novel form of magnetoelectric coupling arising from the orbital reconstruction at the interface between interfacial Mn spins and localized states in the CuO2 planes. This results in a ferromagnetic coupling between the manganite layers that can be controlled by a voltage. Consequently, magnetic tunnel junctions can be electrically toggled between two magnetization states, and the corresponding spin-dependent resistance states, in the absence of a magnetic field.

An anatomical study of transfer of the anterior interosseous nerve for the treatment of proximal ulnar nerve injuries

We conducted an anatomical study to determine the best technique for transfer of the anterior interosseous nerve (AIN) for the treatment of proximal ulnar nerve injuries. The AIN, ulnar nerve, and associated branches were dissected in 24 cadaver arms. The number of branches of the AIN and length available for transfer were measured. The nerve was divided just proximal to its termination in pronator quadratus and transferred to the ulnar nerve through the shortest available route. Separation of the deep and superficial branches of the ulnar nerve by blunt dissection alone, was also assessed. The mean number of AIN branches was 4.8 (3 to 8) and the mean length of the nerve available for transfer was 72 mm (41 to 106). The transferred nerve reached the ulnar nerve most distally when placed dorsal to flexor digitorum profundus (FDP). We therefore conclude that the AIN should be passed dorsal to FDP, and that the deep and superficial branches of the ulnar nerve require approximately 30 mm of blunt dissection and 20 mm of sharp dissection from the point of bifurcation to the site of the anastomosis.

The use of this technique for transfer of the AIN should improve the outcome for patients with proximal ulnar nerve injuries.

Cite this article: Bone Joint J 2014;96-B:789–94.