Quantitative Evaluation of Human Umbilical Vein and Induced Pluripotent Stem Cell-Derived Endothelial Cells as an Alternative Cell Source to Skin-Specific Endothelial Cells in Engineered Skin Grafts

Objective: We compared the capability of human umbilical vein endothelial cells (HUVECs), induced pluripotent stem cell (iPSC)-derived endothelial cells (iECs), and human dermal blood endothelial cells (HDBECs) to effectively vascularize engineered human skin constructs (HSCs) in vitro and on immunodeficient mice. Approach: We quantified the angiogenesis within HSCs both in vitro and in vivo through computational analyses of immunofluorescent (IF) staining. We assayed with real-time quantitative PCR (RT-qPCR) the expression of key endothelial, dermal, and epidermal genes in 2D culture and HSCs. Epidermal integrity and proliferation were also evaluated through haematoxylin and eosin staining, and IF staining. Results: IF confirmed iEC commitment to endothelial phenotype. RT-qPCR showed HUVECs and iECs immaturity compared with HDBECs. In vitro, the vascular network extension was comparable for HDBECs and HUVECs despite differences in vascular diameter, whereas iECs formed unorganized rudimentary tubular structures. In vivo, all ECs produced discrete vascular networks of varying dimensions. HUVECs and HDBECs maintained a higher proliferation of basal keratinocytes. HDBECs had the best impact on extracellular matrix expression, and epidermal proliferation and differentiation. Innovation: To our knowledge, this study represents the first direct and quantitative comparison of HDBECs, HUVECs, and iECs angiogenic performance in HSCs. Conclusions: Our data indicate that HUVECs and iECs can be an alternative cell source to HDBEC to promote the short-term viability of prevascularized engineered grafts. Nevertheless, HDBECs maintain their capillary identity and outperform other EC types in promoting the maturation of the dermis and epidermis. These intrinsic characteristics of HDBECs may influence the long-term function of skin grafts.

Recapitulating T cell infiltration in 3D psoriatic skin models for patient-specific drug testing

Drug screening studies for inflammatory skin diseases are currently performed using model systems that only partially recapitulate human diseased skin. Here, we developed a new strategy to incorporate T cells into human 3D skin constructs (HSCs), which enabled us to closely monitor and quantitate T cell responses. We found that the epidermis promotes the activation and infiltration of T cells into the skin, and provides a directional cue for their selective migration towards the epidermis. We established a psoriatic HSC (pHSC) by incorporating polarized Th1/Th17 cells or CCR6+CLA+ T cells derived from psoriasis patients into the constructs. These pHSCs showed a psoriatic epidermal phenotype and characteristic cytokine profiles, and responded to various classes of psoriasis drugs, highlighting the potential utility of our model as a drug screening platform. Taken together, we developed an advanced immunocompetent 3D skin model to investigate epidermal-T cell interactions and to understand the pathophysiology of inflammatory skin diseases in a human-relevant and patient-specific context.

Recurrent lumbar disc herniation: results of repeat laminectomy and discectomy

Forty-six patients who had previously undergone laminectomy and discectomy for lumbar disc herniation were treated for recurrent disc herniation by repeat laminectomy and discectomy. Fifty recurrences were treated in 46 patients, an average of 7 years and 1 month after the previous laminectomy (range 3 months-22 years and 11 months). Thirty-four patients were treated for 37 recurrences at the same level, with three undergoing a third laminectomy and discectomy. Twelve patients were treated for 13 recurrences at a different level. Four patients underwent a third laminectomy and discectomy for recurrent disc herniation. Forty-one patients had follow-up of at least 1 year and average follow-up was 4 years and 6 months (range 1 year-10 years and 8 months). There were 28 good (69%), 10 fair (24%), and 3 poor (7%) results. Patients with pending litigation or work-related injuries (5 good, 5 fair, and 3 poor) did less well overall than those without these issues (23 good, 5 fair, and 0 poor). Fusion is not routinely required in patients undergoing repeat laminectomy and discectomy for recurrent disc herniation. In the absence of objective evidence of spinal instability, recurrent disc herniation may be adequately treated by repeat lumbar laminectomy and discectomy alone.

Patient outcomes after lumbar spinal fusions

OBJECTIVES

To determine success and complication rates for lumbar spinal fusion surgery, predictors of good outcomes, and whether fusion improves success rates of laminectomy for specific low back disorders.

DATA SOURCES

English-language journal articles published from 1966 through April 1991, identified through MEDLINE searching (spinal fusion plus limiting terms), bibliography review, and expert consultation.

STUDY SELECTION

Articles were selected only if they reported at least 1 year of follow-up data enabling the classification of clinical outcomes as satisfactory or unsatisfactory for at least 30 patients.

DATA EXTRACTION

Two reviewers independently extracted data on patient characteristics, surgical methods, patient outcomes, and quality of study methods.

DATA SYNTHESIS

Of 47 articles, there were no randomized trials. Four nonrandomized studies compared surgery with and without fusion for herniated disks; three found no advantage for fusion. On average, 68% of patients had a satisfactory outcome after fusion, but the range was wide (16% to 95%), and the satisfactory outcome rate was lower in prospective than in retrospective studies. The most frequently reported complications were pseudarthrosis (14%) and chronic pain at the bone graft donor site (9%). Clinical outcomes did not differ by diagnosis or fusion technique, but were worse in studies with a greater number of previously operated patients.

CONCLUSIONS

For several low back disorders no advantage has been demonstrated for fusion over surgery without fusion, and complications of fusions are common. Randomized controlled trials are needed to compare fusion, surgery without fusion, and nonsurgical treatments in rigorously defined patient groups.

Does the Millon Behavioral Health Inventory (MBHI) predict lumbar laminectomy outcome? A comparison with the Minnesota Multiphasic Personality Inventory (MMPI)

Response to surgery for low-back pain is influenced by psychosocial as well as physical factors. However, no psychosocial measure has yet been found to be highly accurate in predicting surgical outcome for individual patients. The purpose of this prospective study was to assess the usefulness of the Millon Behavioral Health Inventory (MBHI) in predicting outcome of laminectomy for lumbar disc herniation or spinal stenosis. Its use was compared with that of the Minnesota Multiphasic Personality Inventory. The influence of several demographic, clinical, and radiographic variables was also investigated. One hundred twenty-seven patients were assessed at an average of 24 months postsurgery. Ninety-three patients had a good outcome, 20 had a fair outcome, and 14 had a poor outcome. The MBHI scales as a group were not associated with surgical outcome.

Surgery for lumbar spinal stenosis. Attempted meta-analysis of the literature

A meta-analysis was undertaken to determine the effects of surgery for lumbar spinal stenosis on pain and disability. Seventy-four journal articles met inclusion criteria and were independently reviewed by two readers. On average, 64% of patients treated surgically for lumbar spinal stenosis were reported to have good-to-excellent outcomes. However, there was wide variation across studies in the percentage with good outcomes. Few patient characteristics were found to predict outcome. Major deficits in study design, analysis, and reporting were common, and these precluded firm conclusions.

Interaction of Staphylococcus aureus toxin "superantigens" with human T cells

A modification of the polymerase chain reaction has been used to establish the fact that a collection of Staphylococcus aureus toxins are "superantigens," each of which interacts with the T-cell alpha beta receptor of human T cells by means of a specific set of V beta elements.

V beta-specific stimulation of human T cells by staphylococcal toxins

The staphylococcal toxins are responsible for a number of diseases in man and other animals. Many of them have also long been known to be powerful T cell stimulants. They do not, however, stimulate all T cells. On the contrary, each toxin reacts with human T cells bearing particular V beta sequences as part of their receptors for major histocompatibility complex protein-associated antigen. The specificity of these toxins for V beta s puts them in the recently described class of superantigens and may account for the differential sensitivity of different individuals to the toxic effects of these proteins.

Does the MMPI predict chemonucleolysis outcome?

Ninety-one patients with lumbar disc herniation were treated by chemonucleolysis with intradiscal chymopapain injection and evaluated at least 1 year after surgery (average, 18 months). There were 54 good, 10 fair, and 27 poor results after chemonucleolysis. Good versus fair/poor outcome groups differed preoperatively on the Minnesota Multiphasic Personality Inventory (MMPI) Hypochondriasis (Hs), Hysteria (Hy), Psychopathic Deviate (Pd), Paranoia (Pa), Hypomania (Ma), and Social Introversion (Si) scales. Presence of compensation issues at the time of surgery was significantly related to outcome, and the MMPI scales provided additional predictive power. Nineteen patients who did not show improvement with chemonucleolysis subsequently underwent lumbar laminectomy and discectomy, and the ultimate outcome for the entire series including these laminectomy patients was 66 good, 10 fair, and 15 poor results. Good versus fair/poor ultimate outcome patients differed significantly on preoperative MMPI Hypochondriasis, Hysteria, Psychopathic Deviate, Paranoia, Psychasthenia, Schizophrenia, Hypomania, and Social Introversion scales. After controlling for the effects of compensation issues, MMPI scales added significantly to the ability to predict ultimate surgical outcome. However, the MMPI could not be used with confidence to predict the outcome for a given patient and should serve only to alert the surgeon to the presence of psychological risk factors and the possible need for referral for psychological evaluation and treatment.

Utility of the MMPI Pain Assessment Index in predicting outcome after lumbar surgery

A Pain Assessment Index (PAI), computed from a weighted combination of MMPI scales scores, has been developed to assess a pain patient's tendency toward continued pain complaints after surgery (Smith & Duerksen, 1979). This study examined the ability of the PAI, determined from presurgery MMPIs, to predict outcome subsequent to lumbar laminectomy and discectomy. One hundred and six chronic low back pain patients (61 males, 45 females) were categorized as having good, fair, or poor outcome 1 year or more postsurgery. Using the cutting score proposed by Smith and Duerksen (1979), the PAI correctly classified 79% of the subjects as having good or fair/poor outcome, and 87% as to whether they were working at follow-up. However, the MMPI Hypochondriasis (HS) scale alone correctly predicted the overall outcome of 83% and the work status of 81% of the subjects. The PAI (and, to a lesser extent, the HS and Hysteria [HY] scales of the MMPI) were found to have good ability to identify patients who were doing well after surgery, but low power in predicting which patients would have a fair or poor surgical result.

A comparison of the Millon Clinical Multiaxial Inventory and the Minnesota Multiphasic Personality Inventory as predictors of successful treatment by lumbar laminectomy

One hundred twenty-nine patients who were treated by lumbar laminectomy for discogenic disease were evaluated preoperation by means of the Millon Clinical Multiaxial Inventory (MCMI) and the Minnesota Multiphasic Personality Inventory (MMPI). At follow-up evaluation, there were 71% good, 18% fair, and 11% poor surgical results. Patients with fair or poor outcomes scored significantly higher in the hypochondriasis, depression, hysteria, and psychasthenia scales in preoperative MMPI testing. These patients also showed significant differences on the MCMI asocial, gregarious, and neurotic depression scales. The MMPI profiles had a higher correlation with successful treatment than did those of the MCMI. The MMPI can help identify patients whose pain syndrome has a significant psychosocial component, and it can easily be used by orthopedic surgeons to facilitate referral and treatment planning.

The major histocompatibility complex-restricted antigen receptor on T cells: distribution on thymus and peripheral T cells

A monoclonal antibody, KJ16-133, which binds to antigen-specific, major histocompatibility complex-restricted (Ag/MHC) receptors on about 20% of BALB/c peripheral T cells has been used to examine the expression of these receptors on thymocytes and different subpopulations of peripheral T cells. Although KJ16-133-reactive receptors were found on mature thymocytes at similar frequencies and levels as on peripheral T cells, these molecules were absent from the first cells to enter the thymus, and in less mature thymocyte populations KJ16-133-reactive cells were less frequent than in the periphery and bore lower quantities of receptor. These results showed that Ag/MHC receptors are present on the surfaces of immature thymocytes, albeit at variable levels, during the time that the repertoire of these cells for Ag/MHC is thought to be selected. Additional experiments showed that KJ16-133 could not be used to distinguish T-cell receptors with different restriction specificities, i.e., for Class I or Class II products of the MHC.

The MMPI as a predictor of outcome in low-back surgery

Between 1965 and 1975, 103 low-back patients were rated preoperatively for general level of functioning, and each completed a Minnesota Multiphasic Personality Inventory (MMPI) test. Following surgery, patients were rated in terms of treatment effectiveness at 6 months and 1 year. The MMPI hypochondriasis and hysteria scales were moderately related to surgical success, as were the severity of initial restriction in the level of functioning and the number of operations performed during the study. However, the MMPI profiles were strikingly similar for all patients. Factors which were not predictive of surgical outcome included age, sex, duration of symptoms, number of back surgeries prior to entering this clinic, and the degree of pathologic condition discovered at operation. The failure to find a potent prediction scheme confirms that MMPI information must be used with considerable caution in treatment planning and only as an adjunct to other clinical and psychological data.