New! Joint IXA-CTRMS 2021 Virtual Congress

Joint Congress of the International Xenotransplantation Association (IXA) and the Cell Transplant and Regenerative Medicine Society (CTRMS), taking place virtually September 23-25, 2021.

Upcoming Webinars 


Monday, March 1, 2021

Open to all healthcare professionals

The emergence of the SARS-CoV-2 pandemic has resulted in substantial morbidity and mortality in the US and worldwide. Vaccines have been developed in record time, with several receiving FDA EUA approval. Understanding the role, features, and side effects of these various vaccines is important to help inform use and expectations. Data are lacking in the transplant population, but physicians should be aware of key principles for protecting their patients.

Notice of Postponement
Donor/Recipient Pair:

Date to be determined

Open to all healthcare professionals

Speaker: Marcelo Cantarovich, TTS President
Moderator: Jean Tchervenkov, Montreal, Canada

Due to unforseen circumstances thsi webinar is postponed

Call for Applications 

Women in Transplantation (WIT) initiative of The Transplantation Society will provide funding to an Early Career Researcher to support research focusing on sex and gender issues relevant to solid organ transplantation.

Letter of intent is due on March 1, 2021

This initiative was made possible with support with One Lambda, a Thermo Fisher Scientific brand, and Sanofi, with each supporting one award.

NCD Lab Launch
Call for Innovative Submissions

We are pleased to announce that the WHO Global Coordination Mechanism on NCDs (GCM/NCD) is launching the first cycle of the Noncommunicable Disease Lab (NCD Lab), a new virtual platform supporting submissions that harness innovative solutions to accelerate progress towards achieving the NCD and NCD-related SDGs.
The NCD Lab provides a platform to mobilize stakeholders, as appropriate, to align and scale action, for the implementation of national NCD and mental health responses. Its vision is to establish a platform that:

1.    Harnesses the power of multisectoral and multistakeholder collaboration
2.    Maintains an “ethos” of innovation both in principle and practice
3.    Propels global development by supporting dynamic initiatives that reduce the burden of NCDs and mental health conditions

Functioning as a WHO platform, it yields the tools to raise awareness of NCDs and can help identify innovative solutions and cross-cutting initiatives working towards reducing the global burden of NCDs and mental health conditions.

The first cycle of the NCD Lab will build on the relevance and success of the following communities:
  • Women and Girls
  • NCDs and the Next Generation 
  • Meaningful involvement of People Living with NCDs
Submissions will be open from February 25th, 2021 until April 8th, 2021. Applicants must be an individual or group of individuals, and may not be submitted on behalf or in the name of any entity. Applicants are required to provide relevant information within the submission form and undergo appropriate WHO screening and due diligence procedures. The types of submissions and inclusion and exclusion criteria can be found in the terms of reference.

We welcome you all to visit the NCD Lab web page for more information and widely share the announcement using the communications materials linked.


Selected Publications by TTS Education Committee. This week's selection made by Drs. Enver Akalin, Millie Samaniego and Marlies Reinders.

A Randomized Trial of Convalescent Plasma in Covid-19 Severe Pneumonia

Ventura A. Simonovich et al. N Engl J Med 2021; 384:619-629 DOI: 10.1056/NEJMoa2031304
A total of 228 patients were assigned to receive convalescent plasma and 105 to receive placebo. The median time from the onset of symptoms to enrollment in the trial was 8 days (interquartile range, 5 to 10), and hypoxemia was the most frequent severity criterion for enrollment. The infused convalescent plasma had a median titer of 1:3200 of total SARS-CoV-2 antibodies (interquartile range, 1:800 to 1:3200). No patients were lost to follow-up. At day 30 day, no significant difference was noted between the convalescent plasma group and the placebo group in the distribution of clinical outcomes according to the ordinal scale (odds ratio, 0.83; 95% confidence interval [CI], 0.52 to 1.35; P=0.46). Overall mortality was 10.96% in the convalescent plasma group and 11.43% in the placebo group, for a risk difference of −0.46 percentage points (95% CI, −7.8 to 6.8). Total SARS-CoV-2 antibody titers tended to be higher in the convalescent plasma group at day 2 after the intervention. Adverse events and serious adverse events were similar in the two groups.

Adaptive immunity to SARS-CoV-2 and COVID-19

Sette et al. Cell;
This is a review article discusses three fundamental components of the adaptive immune system; B cells (the source of antibodies), CD4+ T cells, and CD8+ T cells. The armamentarium of B cells, CD4+ T cells, and CD8+ T cells has differing roles in different viral infections and in vaccines, and thus it is critical to directly study adaptive immunity to SARS-CoV-2 to understand COVID-19. Knowledge is now available on relationships between antigen-specific immune responses and SARS-CoV-2 infection. Although more studies are needed, a picture has begun to emerge that reveals that CD4+T cells, CD8+ T cells, and neutralizing antibodies all contribute to control of SARS-CoV-2 in both non-hospitalized and hospitalized cases of COVID-19. The specific functions and kinetics of these adaptive immune responses are discussed, as well as their interplay with innate immunity and implications for COVID-19 vaccines and immune memory against re-infection.

Prevalence and Predictors of SARS-CoV-2 Antibodies among Solid Organ Transplant Recipients with Confirmed Infection

Daniel Burack et al. Am J Transplant 2021 Feb 16. doi: 10.1111/ajt.16541.
This study enrolled 70 solid organ transplant recipients (56% kidney, 19% lung, 14% liver +/- kidney, and 11% heart +/- kidney recipients) with confirmed SARS-CoV-2 infection who underwent antibody testing with a single commercially available anti-nucleocapsid antibody test at least 7 days after diagnosis in a retrospective cohort. 36 (51%) had positive anti-nucleocapsid antibody testing, and 34 (49%) were negative. Recipients of a kidney allograft were less likely to have positive antibody testing compared those who did not receive a kidney (p=0.04). In the final multivariable model, the years from transplant to diagnosis (OR 1.26, p=0.002) and baseline immunosuppression with more than 2 agents (OR 0.26, p=0.03) were significantly associated with the antibody test result, controlling for kidney transplantation. In conclusion, among SOT recipients with confirmed infection, only 51 % of patients had detectable anti-nucleocapsid antibodies, and transplant-related variables including the level and nature of immunosuppression are important predictors.

Evolution of immune responses to SARS-CoV-2 in mild-moderate COVID-19

Wheatley AK et al. Nat Commun. 2021 Feb 19;12(1):1162,
The authors show a comprehensive profile of antibody, B cell and T cell dynamics over time in a cohort of patients who have recovered from mild-moderate COVID-19. Binding and neutralizing antibody responses, together with individual serum clonotypes, decay over the first 4 months post-infection. A similar decline in Spike-specific CD4+ and circulating T follicular helper frequencies occurs. By contrast, S-specific IgG+ memory B cells consistently accumulate over time, eventually comprising a substantial fraction of circulating the memory B cell pool. Modelling of the concomitant immune kinetics predicts maintenance of serological neutralizing activity above a titer of 1:40 in 50% of convalescent participants to 74 days, although there is probably additive protection from B cell and T cell immunity. This study indicates that SARS-CoV-2 immunity after infection might be transiently protective at a population level. Therefore, SARS-CoV-2 vaccines might require greater immunogenicity and durability than natural infection to drive long-term protection.

Durable SARS-CoV-2 B cell immunity after mild or severe disease

Clinton O Ogega Clin Invest 2021 Feb 11;145516.
Multiple studies have shown loss of SARS-CoV-2 specific antibodies over time after infection, raising concern that humoral immunity against the virus is not durable. If immunity wanes quickly, millions of people may be at risk for reinfection after recovery from COVID-19. However, memory B cells (MBC) could provide durable humoral immunity even if serum neutralizing antibody titers decline. The authors performed multi-dimensional flow cytometric analysis of S protein receptor binding domain (S-RBD)-specific MBC in cohorts of ambulatory COVID-19 patients with mild disease (n = 7), and hospitalized patients with moderate to severe disease (n = 7), at a median of 54 (39-104) days after symptom onset. They detected S-RBD-specific class-switched MBC in 13 of 14 participants, failing only in the individual with lowest plasma levels of anti-S-RBD IgG and neutralizing antibodies. Resting MBC (rMBC) made up the largest proportion of S-RBD-specific MBC in both cohorts. FCRL5, a marker of functional memory on rMBC, was more dramatically upregulated on S-RBD-specific rMBC after mild infection than after severe infection. These data indicate that most SARS-CoV-2-infected individuals develop S-RBD-specific, class-switched rMBC that resemble germinal center-derived B cells induced by effective vaccination against other pathogens, providing evidence for durable B cell-mediated immunity against SARS-CoV-2 after mild or severe disease.




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