The use of human deceased donor skin allograft in burn care

Burns are tissue wounds caused by thermal, electrical, chemical cold or radiation injuries. Deep injuries lead to dermal damage that impairs the ability of the skin to heal and regenerate on its own. Skin autografting following burn excision is considered the current gold standard of care, but lack of patient’s own donor skin or unsuitability of the wound for autografting may require the temporary use of dressings or skin substitutes to promote wound healing, reduce pain, and prevent infection and abnormal scarring. These alternatives include deceased donor skin allograft, xenograft, cultured epithelial cells and biosynthetic skin substitutes. Allotransplantation is the transplantation of cells, tissues, or organs, sourced from a genetically non-identical member of the same species as the recipient. Human deceased donor skin allografts represent a suitable and much used temporizing option for skin cover following burn injury. The main advantages for its use include dermoprotection and promotion of reepithelialisation of the wound and their ability to act as skin cover until autografting is possible or re-harvesting of donor sites becomes available. Disadvantages of its use include the limited abundance and availability of donors, possible transmission of disease, the eventual rejection by the host and its handling storing, transporting and associated costs of provision. This paper will explore the role of allograft skin in burn care, defining the indications for its use in burn management and the future potential for allograft tissue banking.     

Bacterial Contamination of Tissue Allografts – Experiences of the Donor Tissue Bank of Victoria

The aim of this study is to report the experience of the Donor Tissue Bank of Victoria with bacteria isolated from musculoskeletal, skin and cardiac allografts retrieved from cadaveric donors. The results of all quality control samples for bacterial culture, taken during retrieval and processing of allografts at the DTBV for a 12 month period, were extracted and analysed. It was found that 15.7% of skin, 15.1% of heart valves and 5.8% of musculoskeletal samples had positive culture results. The number and types of organisms isolated varied with tissue type. The most commonly isolated organisms were Staphylococcus species (including S. aureus). The identity of the isolate and the number of positive specimens from the same donor were considerations in the decision concerning the suitability of tissue for subsequent implantation.     

Skin allograft procurement and transplantation in Mashhad,Iran: Are burn patients’ needs being met?

Only a single donor’s tissue may save or improve lives of one hundred patients. Unfortunately, low governmental and media support of tissue procurement and transplantation programs is a worldwide problem. Loss of an effective tissue procurement program in many countries like Iran, may lead to loss of many thousands valuable tissues each year. To evaluate the rate of skin donation in Mashhad in comparison to other organs and tissues, we extracted the data related to tissue and organ procurement in Mashhad from 2001. Then we evaluated the annual skin allograft needs in the Burn Department of Imam Reza Hospital as the only referral burn center in the northeast of Iran. Brain dead potential donation rate per million populations of Mashhad in the years 2007–2014 was about 33. The mean refusal rate was 51%. Of patients who have consent for donation, more than 86% have consent for skin donation. Skin allograft procured from 119 (35.5%) candidates. Average of skin retrieval per cadaveric was 1525 cm² with a gradual increase from 1400 cm² in the first year to 1800 cm² in the last year. The recipient to donor ratio was 1.14. It is estimated that about 1 cm² of skin allograft is needed for any cm² burnt body surface area. Considering more than 700 acute burn hospitalization in our burn unit, the patients need for skin allograft would be more than 3.5 million cm², annually. The annual amount of skin procurement in Mashhad has been currently about 20,000 cm². It shows that our patients demand is higher than supply. Skin procurement and transplantation is a simple procedure which can be as lifesaving as organ procurement and transplantation. But there isn’t any national organization to regulate tissue procurement, banking and transplantation. Governmental support of skin procurement and transplantation programs especially nonprofit programs may improve skin procurement rate and save more lives of severely burnt patients.     

Rapid development of tissue bank achieved by International Atomic Energy Agency (IAEA) Tissue Banking Programme in China

Before 1986, the development of tissue banking in China has been slow and relatively uncoordinated. Under the support of International Atomic Energy Agency (IAEA), Tissue Banking in China experienced rapid development. In this period, China Institute for Radiation Protection tissue bank mastered systematic and modern tissue banking technique by IAEA training course and gradually developed the first regional tissue bank (Shanxi Provincial Tissue Bank, SPTB) to provide tissue allograft. Benefit from training course, SPTB promoted the development of tissue transplantation by ways of training, brochure, advertisement and meeting. Tissue allograft transplantation acquired recognition from clinic and supervision and administration from government. Quality system gradually is developing and perfecting. Tissue allograft transplantation and tissue bank are developing rapidly and healthy.     

Supply of human allograft tissue in Canada

There is relatively little known about the supply for allograft tissues in Canada. The major aim of this study is to quantify the current or “Known Supply” of human allograft tissue (bone, tendons, soft tissue, cardiovascular, ocular and skin) from known tissue banks in Canada, to estimate the “Unknown Supply” of human allograft tissue available to Canadian users from other sources, and to investigate the nature and source of these tissue products. Two surveys were developed; one for tissue banks processing one or more tissue types and the other specific to eye banks. Thirty nine sites were initially identified as potential tissue bank respondent sites. Of the 39 sites, 29 sites indicated that they were interested in participating or would consider completing the survey. A survey package and a self-addressed courier envelope were couriered to each of 29 sites. A three week response time was indicated. The project consultants conducted telephone and email follow-up for incomplete data. Unknown supply was estimated by 5 methods. Twenty-eight of 29 sites (97%) completed and returned surveys. Over the past year, respondents reported a total of 5,691 donors (1,550 living and 4,141 cadaveric donors). Including cancellous ground bone, there were 10,729 tissue products produced by the respondent banks. Of these, 71% were produced by accredited banks and 32% were ocular tissues. Total predicted shortfall of allograft tissues was 31,860–66,481 grafts. Through estimating Current supply, and compiling additional qualitative information, this study has provided a snapshot of the current Canadian supply and shortfall of allograft tissue grafts.     

The impact of the International Atomic Energy Agency (IAEA) program on radiation and tissue banking in Cuba

The first multi-tissue bank was founded at Havana in 1958. At that time, freeze-drying was used at the bank as a method of preserving, as well as Cobalt 60 irradiation to sterilise bone tissue, heart valves and others. The impact of the IAEA program in tissue banking activities in Cuba can be summarised as follows: (a) Increase in the production of sterilised tissues using ionising radiation (bone, pig skin and amnion) for medical treatment in the tissue bank of the Hospital Frank Pais; (b) increase of the quality of the productions of bone tissues, pig skin and amnion; (c) reduction in the import of tissues by increasing the local production of tissues; (d) sustainability in the number of donors through the implementation of a public and professional awareness campaign; (e) training of six persons in the Regional Training Centre of Buenos Aires; (f) qualification of one person in the administration of a tissue bank and in the implementation of a Quality System. The amount of tissues produced and sterilised using the ionising radiation techniques in the established banks was 25,510 units. The amount of patients treated with sterilised tissues produced by the established banks was 2,448.     

Peptide nucleic acid antisense prolongs skin allograft survival by means of blockade of CXCR3 expression directing T cells into graft

CXCR3, predominantly expressed on memory/activated T cells, is a receptor for both IFN-gamma-inducible protein 10/CXC chemokine ligand (CXCL)10 and monokine induced by IFN-gamma/CXCL9. It was reported that CXC chemokines IFN-gamma-inducible protein 10/CXCL10 and monokine induced by IFN-gamma/CXCL9 play a critical role in the allograft rejection. We report that CXCR3 is a dominant factor directing T cells into mouse skin allograft, and that peptide nucleic acid (PNA) CXCR3 antisense significantly prolongs skin allograft survival by means of blockade of CXCR3 expression directing T cells into allografts in mice. We found that CXCR3 is highly up-regulated in spleen T cells and allografts from BALB/c recipients by day 7 of receiving transplantation, whereas CCR5 expression is moderately increased. We designed PNA CCR5 and PNA CXCR3 antisenses, and i.v. treated mice that received skin allograft transplantations. The PNA CXCR3 at a dosage of 10 mg/kg/day significantly prolonged mouse skin allograft survival (17.1 +/- 2.4 days) compared with physiological saline treatment (7.5 +/- 0.7 days), whereas PNA CCR5 (10 mg/kg/day) marginally prolonged skin allograft survival (10.7 +/- 1.1 days). The mechanism of prolongation of skin allograft survival is that PNA CXCR3 directly blocks the CXCR3 expression in T cells, which is responsible for directing T cells into skin allograft to induce acute rejection, without interfering with other functions of the T cells. These results were obtained at mRNA and protein levels by flow cytometry and real-time quantitative RT-PCR technique, and confirmed by chemotaxis, Northern and Western blot assays, and histological evaluation of skin grafts. The present study indicates the therapeutic potential of PNA CXCR3 to prevent acute transplantation rejection.     

I-TAC is a dominant chemokine in controlling skin intragraft inflammation via recruiting CXCR3 cells into the graft

Chemokines play a critical role in the acute transplant rejection. In order to provide an overview of the chemokine expression during the course of acute allograft rejection, the intragraft expression profile of 11 chemokines representative of all four chemokine subfamilies was analyzed in a murine skin transplantation model of acute rejection. It was found that RANTES/CCL5, TARC/CCL17 and FKN/CX₃CL1 were expressed at equivalent levels in iso- and allografts. However, the other eight chemokines expression was up-regulated to some extent in allograft compared with that in isograft. The levels of MIP-1α/CCL3, MIP-3α/CCL20 and CTACK/CCL27 were progressively increased from early stage (day 3 post-transplantation) to late stage (day 11). Mig/CXCL9, IP-10/CXCL10, I-TAC/CXCL11, CXCL16 and LTN/XCL1 expression was elevated at middle stage (day 7), and peaked at late stage. Among the up-regulated chemokines, I-TAC was the most obviously elevated chemokine. Therefore, the effect of I-TAC on the skin acute allograft rejection was evaluated. Block of I-TAC by the intradermal injection of anti-I-TAC monoclonal antibody (mAb) reduced the number of CXCR3⁺ cells in skin allograft and significantly prolonged the skin allograft survival. The mAb treatment did not influence the proliferation of the intragraft infiltrating cells in response to the allogeneic antigens, but significantly decreased the number of the infiltrating cells and consequently lowered the secretion of IFN-γ and TNF-α. These data indicate I-TAC might be a dominant chemokine involved in the intradermal infiltration and I-TAC-targeted intervening strategies would have potential application for the alleviation of acute transplant rejection.     

The effect of pregnancy on paternal skin allograft survival

Elucidation of maternal-fetal tolerance mechanisms clarifies the role of regulatory T cells (Treg) in transplant tolerance. This study aim to investigate the effect of pregnancy on paternal skin allograft survival. Flow cytometry techniques, mixed lymphocytes reaction (MLR), PCR, real-time PCR and skin transplantation were key methods. Treg increased significantly from 4.2% before pregnancy to peak at 6.8% day 8 after pregnancy. Both heme oxygenase-1 (HO-1) and indoleamine 2,3-dioxygenase (IDO) mRNA express high in placenta while low in spleen (P<0.05). Although Treg increased during pregnancy, and splenocytes from the pregnant mice showed lower MLR response toward the paternal stimulator, single time pregnancy showed no significant protective effect on paternal skin allograft survival in the tested condition.     

Pretransplant Infusion of Donor B Cells Enhances Donor-Specific Skin Allograft Survival

Pretransplant donor lymphocyte infusion (DLI) has been shown to enhance donor-specific allograft survival in rodents, primates and humans. However, the cell subset that is critical for the DLI effect and the mechanisms involved remain elusive. In this study, we monitored donor cell subsets after DLI in a murine MHC class I L^d-mismatched skin transplantation model. We found that donor B cells, but not DCs, are the major surviving donor APCs in recipients following DLI. Infusing donor B, but not non-B, cells resulted in significantly enhanced donor-specific skin allograft survival. Furthermore, mice that had received donor B cells showed higher expression of Ly6A and CD62L on antigen-specific TCRαβ⁺CD3⁺CD4⁻CD8⁻NK1.1⁻ double negative (DN) regulatory T cells (Tregs). B cells presented alloantigen to DN Tregs and primed their proliferation in an antigen-specific fashion. Importantly, DN Tregs, activated by donor B cells, showed increased cytotoxicity toward anti-donor CD8⁺ T cells. These data demonstrate that donor B cells can enhance skin allograft survival, at least partially, by increasing recipient DN Treg-mediated killing of anti-donor CD8⁺ T cells. These findings provide novel insights into the mechanisms underlying DLI-induced transplant tolerance and suggest that DN Tregs have great potential as an antigen-specific immune therapy to enhance allograft survival.     

Establishing a robust chimeric antigen receptor T-cell therapy program in Australia: the Royal Prince Alfred Hospital experience

>himeric antigen receptor (CAR) T-cell therapy is a novel approved cancer treatment that has shown remarkable efficacy in the treatment of patients with relapsed leukemia and lymphoma. Implementation of CAR T-cell therapy in a hospital setting requires careful and detailed planning because of the complexities in delivering this specialist service. A multi-disciplinary approach with dedicated funding is required to meet clinical, scientific, logistic and regulatory requirements. Tisagenlecleucel was the first approved CAR T-cell therapy in Australia. The treatment has been made available to Australian patients in specialist public hospitals through federal and state funding. Royal Prince Alfred Hospital (RPAH) is one of Australia's oldest tertiary referral public health care institutions and was approved for the provision of CAR T-cell therapy service in 2019. A multi-disciplinary clinical program has been established for the collection and cryopreservation of donor cells shipped for manufacturing as well as for the receipt, storage and administration of CAR T-cell therapy and patient management. The program encompasses a Therapeutic Goods Administration-accredited apheresis unit and a state-of-the-art facility for cell processing, cryopreservation and storage. The program's clinical expertise extends to hematology, oncology, intensive care, pharmacy, neurology and radiology services with direct experience in managing patients receiving CAR T-cell therapies. The introduction of CAR T-cell therapies at RPAH was a complex undertaking facilitated by the existing infrastructure and clinical expertise.     

The Calcineurin-NFAT Axis Controls Allograft Immunity in Myeloid-Derived Suppressor Cells through Reprogramming T Cell Differentiation

While cyclosporine (CsA) inhibits calcineurin and is highly effective in prolonging rejection for transplantation patients, the immunological mechanisms remain unknown. Herein, the role of calcineurin signaling was investigated in a mouse allogeneic skin transplantation model. The calcineurin inhibitor CsA significantly ameliorated allograft rejection. In CsA-treated allograft recipient mice, CD11b⁺ Gr1⁺ myeloid-derived suppressor cells (MDSCs) were functional suppressive immune modulators that resulted in fewer gamma interferon (IFN-γ)-producing CD8⁺ T cells and CD4⁺ T cells (T_H1 T helper cells) and more interleukin 4 (IL-4)-producing CD4⁺ T cells (T_H2) and prolonged allogeneic skin graft survival. Importantly, the expression of NFATc1 is significantly diminished in the CsA-induced MDSCs. Blocking NFAT (nuclear factor of activated T cells) with VIVIT phenocopied the CsA effects in MDSCs and increased the suppressive activities and recruitment of CD11b⁺ Gr1⁺ MDSCs in allograft recipient mice. Mechanistically, CsA treatment enhanced the expression of indoleamine 2,3-dioxygenase (IDO) and the suppressive activities of MDSCs in allograft recipients. Inhibition of IDO nearly completely recovered the increased MDSC suppressive activities and the effects on T cell differentiation. The results of this study indicate that MDSCs are an essential component in controlling allograft survival following CsA or VIVIT treatment, validating the calcineurin-NFAT-IDO signaling axis as a potential therapeutic target in transplantation.     

Micro-organisms isolated from cadaveric samples of allograft musculoskeletal tissue

Allograft musculoskeletal tissue is commonly used in orthopaedic surgical procedures. Cadaveric donors of musculoskeletal tissue supply multiple allografts such as tendons, ligaments and bone. The microbiology laboratory of the South Eastern Area Laboratory Services (SEALS, Australia) has cultured cadaveric allograft musculoskeletal tissue samples for bacterial and fungal isolates since 2006. This study will retrospectively review the micro-organisms isolated over a 6-year period, 2006–2011. Swab and tissue samples were received for bioburden testing and were inoculated onto agar and/or broth culture media. Growth was obtained from 25.1 % of cadaveric allograft musculoskeletal tissue samples received. The predominant organisms isolated were coagulase-negative staphylococci and coliforms, with the heaviest bioburden recovered from the hemipelvis. The rate of bacterial and fungal isolates from cadaveric allograft musculoskeletal tissue samples is higher than that from living donors. The type of organism isolated may influence the suitability of the allograft for transplant.     

Cadaver skin allograft may improve mortality rate for burns involving over 30% of total body surface area: a propensity score analysis of data from four burn centers

Cadaver skin is used for temporary wound covering, but there is insufficient evidence regarding its clinical usefulness in patients with major burns. We aimed to analyze the effect of cadaveric skin allograft on mortality rates in patients with burns involving >?30% of total body surface area (TBSA). Our study included 1282 patients with >?30% of TBSA burned admitted to four hospitals in Korea between June 1, 2008 and December 31, 2016. Of these, 698 patients underwent cadaver skin allograft (cadaver group), and 584 were treated with conventional treatment (non-cadaver group). We corrected the differences between the two groups using propensity score matching, and generated 474 propensity score-matched pairs. Overall 90-day in-hospital mortality rate among all patients was 35.3% (453/1282). There was a significant difference in 90-day in-hospital mortality between the two groups for both unmatched [cadaver vs. conventional, 31.7 vs. 39.7%; difference, 8.0; 95% confidence interval (CI) 2.8–13.3] and propensity-matched groups (37.8 vs. 47.3%; difference, 9.5; 95% CI 3.2–15.8). Logistic regression analyses showed a significant association between cadaver skin allograft and lower 90-day in-hospital mortality in the propensity-matched groups (odds ratio, 0.42; 95% CI 0.29–0.62). Patients with major burns who underwent cadaver skin allograft had a lower mortality rate compared to those who did not. Cadaver skin allograft may improve the survival of patients with major burns, especially in the early phase of injury.     

Our Clinical Experience using Cryopreserved Cadaveric Allograft for the Management of Severe Burns

Human cadaveric allograft is the most commonly used alternative wound closure material for excised burn wounds when limited donor sites or the overall patient condition does not permit immediate grafting with autologous skin. The Skin Bank in Singapore has supplied a total of 33,000 cm² of cryopreserved cadaveric allograft to the Burns Centre in Singapore for the early post-burn treatment of 17 severely burned patients with body surface area (BSA) burn wounds averaging 58% (range 33–90). An average of 13% (range 3–30%) cadaveric allograft was transplanted on 17 patients. Seven patients had recovered from their burn injuries and ten patients died of multiple complications related to their burn injuries. Our clinical observation has shown good adherence of cadaveric allograft when applied on clean and debrided wound bed after 4–7 days of post-operation. The availability of cadaveric allograft permits early excision and wound coverage before the patients' condition is further compromised. Our clinical experience using cryopreserved cadaveric allograft is proving to be indispensable in the management of patients with severe burns. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inaccuracy in selection of massive bone allograft using template comparison method

The use of massive bone allografts is increasing year by year and selection method remains unchanged. Superposition of patient’s radiograph over allograft image and comparison of distances is the gold standard. Experiment was led to test selection procedure of a major european tissue bank. Four observers were asked to select an allograft for 10 fictive recipients. Nine allografts were provided. To simulate a perfect allograft, recipient himself was inserted in the pool of allografts (trap graft). The 10 potential bone transplants were classified in four categories (from adequate to unacceptable). In addition, observers were asked to choose the three best grafts for a given recipient. Quadratic kappa measuring agreement on classification between two observers ranged between 0.74 (substantial) and 0.47 (moderate). Trap graft was quoted by observers as adequate four times (10%) and was cited eight times (20%) among the three best matching allografts. None of the observers discovered that recipient was among allograft panel. This study demonstrates that current selection method is inaccurate for hemipelvic allograft selection. New methods should be developed and tested to assist tissue banks in bone allograft selection.     

The impact of the International Atomic Energy Agency (IAEA) program on radiation and tissue banking in Korea

In 1971, first bone bank was established at the Department of Orthopaedic Surgery in Catholic University of Korea. The first clinical case was reported at the Journal of Korean Orthopaedic Association in 1973. Subsequently, more than 60 surgical bone banks were established in the university and teaching hospitals throughout country. In 1990, the Korea Biomaterial Research Institute (KBRI) organised the IAEA/RCA training course on tissue banking. In this course students from 17 countries participated. In 1994 the first collaboration for cadaver tissue recovery was performed. It is important to single out that the various religious groups in Korea have favourable attitudes towards tissue donation, which contributes to the success of the tissue banking programs in the country. The demands of allograft were getting increased in the Korean medical and dental society. Currently, 62 hospital based bone banks, 5 processing tissue banks, 1 regional tissue bank and more than 30 tissue distributors are working in Korea. Based on the U.S.A. usage of more than 1,000,000 grafts per year, 100,000–200,000 grafts will be needed in Korea. Those findings indicate a greatly increased need for training of tissue bank operators. The Korean society will need at least 20–30 tissue bank operators for training in every year. The National Training Centre (NTC) for tissue bank operators and medical personal using the IAEA Curriculum in the Korean languages was established in 2003. From 2004 to 2006, NTC have been trained 40 tissue bank operators. They have produced at least 10,000 tissues per year. These figures indicate a cost saving of US$ 10 million. Within 5 years, NTC will train 100 tissue bank operators. These individuals and their respective banks will provide an increasing number of high quality grafts to the communities they serve at a cost far less than if they were acquired from abroad.     

Screening for the prevention of cervical cancer in the era of human papillomavirus vaccination: an Australian perspective

Australia has a unique and highly successful screening program for cervical cancer which is based on the conventional Pap smear. Since its introduction in 1991 there has been a decline in both the incidence of and mortality from this disease. Part of the success of this program has been the introduction of Pap test registers and strict quality assurance measures for cervical cytology, including compulsory key performance indicators for laboratories. Using these measures, nationwide calculations give cervical cytology in Australia a sensitivity of 78% for high-grade lesions and a positive predictive value (PPV) of 78%. Australia was the first country to introduce a widespread government-funded human papillomavirus (HPV) vaccination program in 2007. Because of the high accuracy of Australian cytology, HPV testing alone, given its low PPV and high cost, is unlikely to be a viable alternative to cytology for primary screening in this country. Australia therefore faces unique issues and choices in integrating its extensive vaccination program with a successful cervical screening program.     

Roles of deletion and regulation in creating mixed chimerism and allograft tolerance using a nonlymphoablative irradiation-free protocol

The induction of mixed chimerism (MC) is a powerful and effective means to achieve transplantation tolerance in rodent models. Host conditioning with irradiation or cytotoxic drugs has been used in many protocols for chimeric induction across allogeneic barriers. The deletion of alloreactive T cell clones has been described as the main mechanism responsible for the induction of a stable MC. In this study, we demonstrate that a stable MC and skin allograft tolerance can be established across MHC barriers by a noncytotoxic, irradiation-free approach using costimulation blockade plus rapamycin treatment. By using an adoptive transfer model of skin allograft and using specific Vbeta TCR probes, we demonstrated that deletion of donor-reactive cytopathic T cell clones is indeed profound in tolerant hosts. Nonetheless, the challenge of tolerant mixed chimeras with 5 million mononuclear leukocytes (MNL) from naive syngeneic mice was neither able to abolish the stable MC nor to trigger skin allograft rejection, a hallmark of peripheral, not central tolerance. Furthermore, in an adoptive transfer model, MNLs harvested from tolerant hosts significantly inhibited the capacity of naive MNLs to reject same donor, but not third-party, skin allografts. Moreover, when we transplanted skin allografts from stable tolerant chimeras onto syngeneic immune-incompetent mice, graft-infiltrating T cells migrated from the graft site, expanded in the new host, and protected allografts from acute rejection by naive syngeneic MNLs. In this model, both deletional and immunoregulatory mechanisms are active during the induction and/or maintenance of allograft tolerance through creation of MC using a potentially clinically applicable regimen.     

Residual herbicide treatments reduce Andropogon gayanus (Gamba Grass) recruitment for mine site restoration in northern Australia

Weed invasion is a major threat to Australian tropical savannas, and controlling weeds is essential for successful re‐establishment of native species on disturbed sites. Gamba Grass (Andropogon gayanus) is an African grass which has invaded large areas of tropical savanna across northern Australia. Current management strategies in northern Australia focus on fire and glyphosate to effectively control mature plants; however, re‐establishment of infestations from the soil seed bank remains a major challenge to eradication efforts. This study focused on the effects of soil seed bank treatments on Gamba Grass recruitment on a mine site in northern Australia. Adult Gamba Grass plants within test plots were killed with glyphosate to exclude resource competition. Chemical, physical and biological treatments were then applied, and the treatment effects on subsequent Gamba Grass seedling emergence and survival quantified. Seedling emergence was significantly reduced by three of the four residual herbicide treatments tested. The most effective herbicide treatments, dalapon and sulfometuron, reduced emergence by 90% compared to the standard glyphosate treatment alone. This equated to a reduction in Gamba Grass seedling emergence from 1 seedling/m² to 1 seedling 10 m^?2, a major improvement for Gamba Grass management. These residual herbicide treatments significantly reduced the population density of Gamba Grass for at least 5 months after emergence. The physical and biological treatments did not have a significant effect on seedling emergence. This significant reduction in Gamba Grass seedling emergence and survival can substantially improve Gamba Grass management. Reducing re‐colonisation from the soil seed bank using residual herbicides provides a valuable management tool for land managers, integrating readily with established strategies for controlling the mature plants.