scholarly journals Autologous Stem Cell Transplantation Disrupts Adaptive Immune Responses during Rebound Simian/Human Immunodeficiency Virus Viremia

2017 ◽  
Vol 91 (13) ◽  
Author(s):  
Daniel B. Reeves ◽  
Christopher W. Peterson ◽  
Hans-Peter Kiem ◽  
Joshua T. Schiffer

ABSTRACT Primary HIV-1 infection induces a virus-specific adaptive/cytolytic immune response that impacts the plasma viral load set point and the rate of progression to AIDS. Combination antiretroviral therapy (cART) suppresses plasma viremia to undetectable levels that rebound upon cART treatment interruption. Following cART withdrawal, the memory component of the virus-specific adaptive immune response may improve viral control compared to primary infection. Here, using primary infection and treatment interruption data from macaques infected with simian/human immunodeficiency virus (SHIV), we observe a lower peak viral load but an unchanged viral set point during viral rebound. The addition of an autologous stem cell transplant before cART withdrawal alters viral dynamics: we found a higher rebound set point but similar peak viral loads compared to the primary infection. Mathematical modeling of the data that accounts for fundamental immune parameters achieves excellent fit to heterogeneous viral loads. Analysis of model output suggests that the rapid memory immune response following treatment interruption does not ultimately lead to better viral containment. Transplantation decreases the durability of the adaptive immune response following cART withdrawal and viral rebound. Our model's results highlight the impact of the endogenous adaptive immune response during primary SHIV infection. Moreover, because we capture adaptive immune memory and the impact of transplantation, this model will provide insight into further studies of cure strategies inspired by the Berlin patient. IMPORTANCE HIV patients who interrupt combination antiretroviral therapy (cART) eventually experience viral rebound, the return of viral loads to pretreatment levels. However, the “Berlin patient” remained free of HIV rebound over a decade after stopping cART. His cure is attributed to leukemia treatment that included an HIV-resistant stem cell transplant. Inspired by this case, we studied the impact of stem cell transplantation in a macaque simian/HIV (SHIV) system. Using a mechanistic mathematical model, we found that while primary infection generates an adaptive immune memory response, stem cell transplantation disrupts this learned immunity. The results have implications for HIV cure regimens based on stem cell transplantation.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 64-64
Author(s):  
Tippi MacKenzie ◽  
Erin Jarvis ◽  
Amar Nijagal ◽  
Tom Le ◽  
Marta Wegorzewska ◽  
...  

Abstract Abstract 64 In utero hematopoietic stem cell transplantation (IUHSCTx) is a promising treatment strategy for many congenital hematopoietic disorders such as immunodeficiencies. However, clinical applications have been hampered by lack of engraftment, possibly secondary to a host immune response. This has been a conundrum in the field, since the fetus can also be tolerized to allogeneic cells in some circumstances. We hypothesized that it is the maternal immune response which limits engraftment of in utero transplanted cells. Methods: Fetal BALB/c mice at 14 days' gestation were transplanted with age-matched fetal liver (FL) cells (2.5 × 106 cells/fetus) from allogeneic C57B6 mice and levels of circulating donor cell chimerism were determined serially starting at 4 weeks after in utero transplantation. Rates of engraftment (number of chimeric pups/number of surviving pups) and levels of chimerism (donor CD45 cells/total CD45 cells) were compared to controls in which animals were transplanted with congenic cells (C57B6 (CD45.2) fetal hosts transplanted with C57B6 (CD45.1) FL). In order to determine the role of the maternal adaptive immune system, immunodeficient BALB/c.Rag−/− mothers (deficient in T and B cells) were bred to wild type BALB/c males, such that the fetuses (BALB/c.Rag+/−) would be immunocompetent. These fetuses were transplanted with C57B6 FL and rates of engraftment and levels of chimerism in these transplants were compared to those in wild type allogeneic transplants. In order to determine whether the maternal influence is caused by maternal lymphocytes trafficking into the fetus, C57B6 (CD45.2) females were bred to C57B6 (CD45.1) males, such that the fetal cells (CD45.1+/CD45.2+) could be distinguished from maternal cells (CD45.1−/CD45.2+). Fetal blood and tissues were examined for the presence of maternal cells by flow cytometry at various gestational ages. Results: The rate of engraftment after IUHSCTx in control animals transplanted with congenic cells was 14/16 (88%) and average levels of chimerism were 9.9±8.4%. In contrast, the rate of engraftment in wild-type BALB/c fetuses transplanted with allogeneic B6 cells was 11/25 (44%; p<0.05 compared to congenic), and levels of chimerism were 21±19 (p=NS), confirming there is an adaptive immune response to fetal stem cell transplantation. As expected, chimeric animals were tolerant to the donor strain by mixed lymphocyte reaction while injected, non-chimeric animals were sensitized. However, in the absence of a maternal adaptive immune system, rates of chimerism (in immunocompetent BALB/c.Rag+/− pups) increased to 100% (n=10, p<0.05 compared to wild type allogeneic) and levels of chimerism were significantly higher (44±18, p<0.05). Levels of chimerism in engrafted animals declined over time after allogeneic transplantation but not after congenic transplantation, indicating there is a second, late phase immune response to allogeneic cells. However, chimerism levels did not decline in the BALB/c.Rag+/− recipients, suggesting that the maternal immune system has long-lasting effects on the success of fetal transplantation, perhaps by priming the host immune system. In our analysis of maternal/fetal cellular trafficking, we detected maternal lymphocytes in the blood of midgestation fetuses (14±7% at E12.5–E14.5, n=9) which declined gradually and was undetectable after birth. Lineage analysis demonstrated that 45±15 % of maternal cells are Gr-1+ granulocytes and 21±15% are B cells. Trafficking of maternal cells into the fetus was increased following fetal manipulation (injection of PBS < injection of allogeneic HSC). Conclusions: There is an adaptive immune response which limits early engraftment after in utero transplantation of allogeneic cells and leads to a gradual decline in levels of chimerism in engrafted animals. However, in the selective absence of maternal T and B cells, all fetuses transplanted with allogeneic FL cells show long-term, multilineage engraftment and demonstrate donor-specific tolerance. These results indicate that the maternal immune system plays a significant role in the success of fetal HSC transplantation. Cellular trafficking between the mother and fetus may be a mechanism by which maternal lymphocytes encounter cells transplanted into the fetus. Our findings have clinical implications in that the success of IUHSCTx may be improved by harvesting cells from the mother or HLA-matching cells to the mother. Disclosures: No relevant conflicts of interest to declare.


2021 ◽  
Vol 10 (5) ◽  
pp. 1113
Author(s):  
Kinga Musiał ◽  
Krzysztof Kałwak ◽  
Danuta Zwolińska

Background: Knowledge about the impact of allogeneic hematopoietic stem cell transplantation (alloHSCT) on renal function in children is still limited. Objectives: The aim of the study was to evaluate kidney function in children undergoing alloHSCT, with special focus on differences between patients transplanted due to oncological and non-oncological indications. Materials and Methods: The data of 135 children undergoing alloHSCT were analyzed retrospectively. The serum creatinine and estimated glomerular filtration rate (eGFR) values were estimated before transplantation at 24 h; 1, 2, 3, 4 and 8 weeks; and 3 and 6 months after alloHSCT. Then, acute kidney injury (AKI) incidence was assessed. Results: Oncological children presented with higher eGFR values and more frequent hyperfiltration rates than non-oncological children before alloHSCT and until the 4th week after transplantation. The eGFR levels rose significantly after alloHSCT, returned to pre-transplant records after 2–3 weeks, and decreased gradually until the 6th month. AKI incidence was comparable in oncological and non-oncological patients. Conclusions: Children undergoing alloHSCT due to oncological and non-oncological reasons demonstrate the same risk of AKI, but oncological patients may be more prone to sustained renal injury. Serum creatinine and eGFR seem to be insufficient tools to assess kidney function in the early post-alloHSCT period, when hyperfiltration prevails, yet they reveal significant differences in long-term observation.


Author(s):  
Hao Dai ◽  
Olaf Penack ◽  
Aleksandar Radujkovic ◽  
David Schult ◽  
Joshua Majer-Lauterbach ◽  
...  

AbstractHyperbilirubinemia occurs frequently after allogeneic stem cell transplantation. Causes include primary liver damage and endothelial complications as major contributors. Here, we have investigated the impact of early bilirubinemia (EB) on posttransplant outcomes. Maximum total bilirubin levels (days 0–28) were categorized using maximally selected log rank statistics to identify a cut off for the endpoint non-relapse mortality (NRM) in a training cohort of 873 patients. EB above this cut off was correlated with NRM and overall survival (OS) and with pre- and posttransplant Angiopoietin-2, interleukin (IL)18, CXCL8 and suppressor of tumorigenicity-2 (ST2) serum levels, and the endothelial activation and stress index (EASIX). Clinical correlations were validated in a sample of 388 patients transplanted in an independent institution. The EB cut off was determined at 3.6 mg/dL (61.6 µM). EB predicted OS (HR 1.60, 95% CI 1.21–2.12, p < 0.001), and NRM (CSHR 2.14; 1.28–3.56, p = 0.004), also independent of typical endothelial complications such as veno-occlusive disease, refractory acute graft-versus-host disease, or transplant-associated microangiopathy. However, EB correlated with high Angiopoietin-2, EASIX-pre and EASIX-day 0, as well as increased levels of posttransplant CXCL8, IL18, and ST2. In summary, EB indicates a poor prognosis. The association of EB with endothelial biomarkers suggests an endothelial pathomechanism also for this posttransplant complication.


Blood ◽  
2004 ◽  
Vol 103 (6) ◽  
pp. 2003-2008 ◽  
Author(s):  
Michael Boeckh ◽  
W. Garrett Nichols

AbstractIn the current era of effective prophylactic and preemptive therapy, cytomegalovirus (CMV) is now a rare cause of early mortality after hematopoietic stem cell transplantation (HSCT). However, the ultimate goal of completely eliminating the impact of CMV on survival remains elusive. Although the direct effects of CMV (ie, CMV pneumonia) have been largely eliminated, several recent cohort studies show that CMV-seropositive transplant recipients and seronegative recipients of a positive graft appear to have a persistent mortality disadvantage when compared with seronegative recipients with a seronegative donor. Recipients of T-cell–depleted allografts and/or transplants from unrelated or HLA-mismatched donors seem to be predominantly affected. Reasons likely include both incomplete prevention of direct and indirect or immunomodulatory effects of CMV as well as consequences of drug toxicities. The effect of donor CMV serostatus on outcome remains controversial. Large multicenter cohort studies are needed to better define the subgroups of seropositive patients that may benefit from intensified prevention strategies and to define the impact of CMV donor serostatus in the era of high-resolution HLA matching. Prevention strategies may require targeting both the direct and indirect effects of CMV infection by immunologic or antiviral drug strategies.


Blood ◽  
2021 ◽  
Author(s):  
Mariapia A Degli-Esposti ◽  
Geoffrey R Hill

The reactivation of viruses from latency after allogeneic stem cell transplantation (SCT) continues to represent a major clinical challenge requiring sophisticated monitoring strategies in the context of prophylactic and/or pre-emptive antiviral drugs that are associated with significant expense, toxicity, and rates of failure. Accumulating evidence has demonstrated the association of polyfunctional virus-specific T-cells with protection from viral reactivation, affirmed by the ability of adoptively transferred virus-specific T-cells to prevent and treat reactivation and disease. The roles of innate cells (NK cells) in early viral surveillance, and dendritic cells in priming of T-cells have also been delineated. Most recently, a role for strain-specific humoral responses in preventing early cytomegalovirus (CMV) reactivation has been demonstrated in preclinical models. Despite these advances, many unknowns remain: what are the critical innate and adaptive responses over time, is the origin (e.g. recipient versus donor) and localization (e.g. in parenchymal tissue versus lymphoid organs) of these responses important, how does GVHD and the prevention/treatment thereof (e.g. high dose steroids) impact the functionality and relevance of a particular immune axis, do the immune parameters that control latency, reactivation and dissemination differ, and what is the impact of new antiviral drugs on the development of enduring antiviral immunity. Thus, whilst antiviral drugs have provided major improvements over the last two decades, understanding the immunological paradigms underpinning protective antiviral immunity after SCT offers the potential to generate non-toxic immune-based therapeutic approaches for lasting protection from viral reactivation.


Vaccines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 79
Author(s):  
Mikiko Watanabe ◽  
Angela Balena ◽  
Davide Masi ◽  
Rossella Tozzi ◽  
Renata Risi ◽  
...  

Obesity is associated with a poor COVID-19 prognosis, and it seems associated with reduced humoral response to vaccination. Public health campaigns have advocated for weight loss in subjects with obesity, hoping to eliminate this risk. However, no evidence proves that weight loss leads to a better prognosis or a stronger immune response to vaccination. We aimed to investigate the impact of rapid weight loss on the adaptive immune response in subjects with morbid obesity. Twenty-one patients followed a hypocaloric, very-low-carbohydrate diet one week before to one week after the two mRNA vaccine doses. The diet’s safety and efficacy were assessed, and the adaptive humoral (anti-SARS CoV-2 S antibodies, Abs) and cell-mediated responses (IFNγ secretion on stimulation with two different SARS CoV-2 peptide mixes, IFNγ-1 and IFNγ-2) were evaluated. The patients lost ~10% of their body weight with metabolic improvement. A high baseline BMI correlated with a poor immune response (R −0.558, p = 0.013 for IFNγ-1; R −0.581, p = 0.009 for IFNγ-2; R −0.512, p = 0.018 for Abs). Furthermore, there was a correlation between weight loss and higher IFNγ-2 (R 0.471, p = 0.042), and between blood glucose reduction and higher IFNγ-1 (R 0.534, p = 0.019), maintained after weight loss and waist circumference reduction adjustment. Urate reduction correlated with higher Abs (R 0.552, p = 0.033). In conclusion, obesity is associated with a reduced adaptive response to a COVID-19 mRNA vaccine, and weight loss and metabolic improvement may reverse the effect.


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