The Freemartin Cattle and Clinical Transplantation: From the Ancients to Modern Day.

This historical retrospective explores the study of the freemartin condition and its impact on the discovery of immunologic tolerance and the field of transplant surgery-from the ancient Romans, to early modern anatomists Valsalva, Scarpa, and Hunter, to contemporary immunologists Owen, Medawar, and Billingham, and to legendary transplant surgeon Joseph Murray. The legacy of freemartin cattle in the understanding of acquired tolerance and transplant immunology represents generations of scientific inquiry guided by careful observation and occasional serendipity, and the present-day immunologists and surgeons exploring immune transplant tolerance owe much to the history of the freemartin, several millennia in the making.

Trasplante de tejidos compuestos: avances y cuestiones pendientes / Composite tissue transplantation: progress and outstanding issues

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Medawar's legacy to cellular immunology and clinical transplantation: a commentary on Billingham, Brent and Medawar (1956) 'Quantitative studies on tissue transplantation immunity. III. Actively acquired tolerance'.

'Quantitative studies on tissue transplantation immunity. III. Actively acquired tolerance', published in Philosophical Transactions B in 1956 by Peter Medawar and his colleagues, PhD graduate Leslie Brent and postdoctoral fellow Rupert Billingham, is a full description of the concept of acquired transplantation tolerance. Their 1953 Nature paper (Billingham RE et al. 1953 Nature 172, 603-606. (doi:10.1038/172603a0)) had provided initial evidence with experimental results from a small number of neonatal mice, with mention of similar findings in chicks. The Philosophical Transactions B 1956 paper is clothed with an astonishing amount of further experimental detail. It is written in Peter Medawar's landmark style: witty, perceptive and full of images that can be recalled even when details of the supporting information have faded. Those images are provided not just by a series of 20 colour plates showing skin graft recipient mice, rats, rabbits, chickens and duck, bearing fur or plumage of donor origin, but by his choice of metaphor, simile and analogy to express the questions being addressed and the interpretation of their results, along with those of relevant published data and his prescient ideas of what the results might portend. This work influenced both immunology researchers and clinicians and helped to lay the foundations for successful transplantation programmes. It led to the award of a Nobel prize in 1960 to Medawar, and subsequently to several scientists who advanced these areas. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.

The next frontier in composite tissue allotransplantation.

Solid organ transplantations became a clinical option in the 1950s. The hand allograft was the pioneer of composite tissue allotransplantation (CTA), successfully started near the end of the last century despite arguments over the practicality and methods. Since then, CTA such as hand and face has continued to progress from the theoretical to clinical reality. The treatment principles, drug combinations, and mechanisms of the immunosuppression medications on which contemporary transplant surgeries have been based continue to develop as researchers and physicians gain more experience in the CTA field. It could be argued that the ethical issues associated with CTA have prevented evolution of the field rather than surgical or technical skill. This is particularly true for allo-head and body reconstruction (AHBR). How can leaders in the field of CTA develop a model that would satisfy ethical concerns? Bolstered by recent successes in the field, is it time to traverse the next frontier? Can AHBR ever be a feasible option in the clinical setting? The reader will be provided with a brief history of CTA from theory to research to clinical practice. A concise description of AHBR as it pertains to the critical procedure (i.e., surgery design) will also be discussed.

Tom Gibson, Plastic Surgeon (1915-93): Allograft rejection by the immune system and prediction of free tissue transplantation.

Tom Gibson made enormous contributions to the modern development of Plastic and Reconstructive Surgery. His key 1943 paper 'The fate of skin homografts in man' described the 'second set' phenomenon attributing graft rejection to an immunological phenomenon. Later in his career he visualised the concept of microvascular tissue transplantation and inspired many young surgeons through his various roles of Director of the unit at Canniesburn Hospital, Professor of Bioengineering and President of the Royal College of Physicians and Surgeons of Glasgow.

'The shape of the human being as a function of time': time, transplantation, and tolerance in Peter Brian Medawar's research, 1937-1956.

Using tissue transplantation, the British scientist Peter Brian Medawar showed how extrinsic cells could be permanently integrated into an animal's body without provoking immune responses. With his study of this phenomenon--which he called 'actively acquired tolerance'--Medawar was awarded the Nobel Prize in Medicine and Physiology in 1960 along with the Australian scientist Frank Macfarlane Burnet, who theoretically predicted the possibility. The monumental work of Medawar stems from his long and deep interest in the nature of living organisms' changes over time, such as growth, aging, and evolution. In particular, his concern for the phenomenon of decline played a critical role in his research design regarding tolerance and its interpretation.

The history of human composite tissue allotransplantation.

Restoration of amputations and disfigurement are represented in ancient mythology, but the modern history of composite tissue allotransplantation begins with World War II injuries that generated seminal immunologic experiments by Medawar and co-workers. These studies led to the first successful human allografts in the 1950s by Peacock with composite tissue and Murray and co-workers with solid organs. Pharmacologic immunosuppression brought rapid growth of solid organ transplantation over the next 50 years, but composite tissue transplantation virtually disappeared. This evolution was judged to be a consequence of the greater antigenicity of skin, which that was insurmountable by the available immunosuppression. In the mid-1990s, progress in immunosupression allowed skin-bearing grafts, led by successful hand transplants, which produced a renaissance in composite tissue allotransplantation. Since then, graft types have expanded to over 10, and graft numbers to over 150, with success rates that equal or exceed solid organs. The field has emerged as one of the most exciting in contemporary medicine, although accompanied by substantial challenges and controversy. This paper reviews the origins and progress of this field, assessing its potential for future evolution.

[Development and status quo of testis transplantation].

A lot of advances have been made in testis autotransplantation, testis homotransplantation, testicular tissue transplantation, Leydig cell transplantation and spermatogonial stem cell transplantation in the past decades. And recent years, have witnessed remarkable progress in Leydig cell transplantation and spermatogonial stem cell transplantation, which promise to be new means for the treatment of male infertility and hypogonadism. The development and present state of testis transplantation are summarized in this paper based on the related literature of recent years.

Tracheal replacements: part 1.

In this review, we summarize the history of tracheal reconstruction and replacement as well as progress in current tracheal substitutes. In Part 1, we cover the historical highlights of grafts, flaps, tube construction, and tissue transplants and address the progress made in tracheal stenting as a means of temporary tracheal support. This is followed in Part 2 by an analysis of solid and porous tracheal prostheses in experimental and clinical trials. We conclude Part 2 with a summary of recent efforts toward generating a bioengineered trachea. Finally, we provide an algorithm on the spectrum of options available for tracheal replacement.

Técnica do enxerto dobrado (Abrams, 1980) utilizado na Implantodontia. Relato de caso / Technique of the folded flap (Abrams, 1980) used in Implantology. A clinical case report

A técnica do retalho dobrado foi desenvolvida por Abrams, em 1980, com a finalidade de corrigir defeitos apresentados na vestibular de rebordos edêntulos. Apresenta como vantagens: aspecto gengival estético; previsibilidade porque o enxerto mantém conexão e recebe suprimento sanguíneo e, é realizado em apenas um ato cirúrgico, ao contrário das técnicas do enxerto em envelope e do enxerto onlay. O enxerto dobrado foi idealizado para utilização em regiões desdentadas que irão receber próteses fixas. O propósito deste trabalho é mostrar a utilização da técnica do enxerto dobrado numa região que recebeu implante e apresenta depressão na região vestibular do incisivo central superior direito.

The technique of the folded graft was developed by Abrams in 1980, with the purpose to correct defects presented in the vestibular contest of edentulous rims. It presents as advantages: aesthetic gengival aspect; previsibility because the graft keeps connection and receives blood suppliment, and is made in one surgical act, against the techniques of submucosal graft and onlay graft. The folded graft was idealized for use in edentulous regions that will go to receive fixed prosthesis. The intention of this work is to show the use of the technique of folded graft in a region that receives implantation, however presents depression in the upper right central incisor's area.