HLA-B*35 as a new marker for susceptibility to human T-cell lymphotropic virus type 1 (HTLV-1) Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) in patients living in Argentina.

BACKGROUND: Human T-cell lymphotropic virus type 1 (HTLV-1) is the etiological agent of HTLV associated myelopathy/ Tropical Spastic Paraparesis (HAM/TSP) and Adult T cell leukemia/lymphoma (ATLL), in around 2-5% of the infected individuals. Host genetic background might play a role in disease progression. Several previous studies across many countries report HLA haplotype to be one such factor. Here, we sequenced HLA-A, -B and -C of 66 individuals by Sequence-Based Typing (SBT), and compared the frequency of different alleles among ATLL patients, HAM/TSP patients, asymptomatic carriers and non-infected individuals living in Argentina. RESULTS: The frequency of HLA-A, -B and -C alleles largely matched that of the general population in Argentina. We identified HLA-A*02, HLA-B*35 and HLA-C*07 as associated to protection from ATLL (p = 0.031), susceptibility to HAM/TSP (p < 0.001) and susceptibility to ATLL (p = 0.017), respectively. We also found a strong correlation between high proviral load (PVL) and disease (p = 0.008), but were unable to identify any particular allele associated with high or low PVL. CONCLUSIONS: We have found HLA-A*02, HLA-B*35 and HLA-C*07 to be associated to protection from ATLL (HLA-A*02) and susceptibility to HAM/TSP (HLA-B*35) or to ATLL (HLA-C*07), respectively. Whereas HLA-A*02 protection from ATLL has already been extensively described in other regions of the world, this is the first report that links HLA-B*35 and an increased susceptibility to HAM/TSP. As for HLA-C*07 it has previously been associated to susceptibility to HAM/TSP in other countries but in our population it has been linked to ATLL.

Evaluation of the humoral response to the third dose of SARS-COV-2 vaccines in liver transplant recipients.

Solid organ transplant recipients (SOTR) commonly develop an unsatisfactory humoral response to vaccines compared to immunocompetent individuals (IC). We have previously evaluated the humoral response in liver transplant recipients (LTR) who received two-dose vaccines against SARS-CoV-2 and reported that 38 % of LTR did not produce anti-Spike antibodies. Thus, we set out to evaluate the humoral response after the third dose of SARS-CoV-2 vaccines. For this purpose, samples from a cohort of 81 LTR and 27 IC were extracted between 21 and 90 days after the third dose. Serology for anti-Spike IgG antibodies and neutralizing antibodies against Wuhan, Delta and Omicron variants were evaluated. We found that 73.5 % of LTR were responders for anti-Spike IgG, while all the IC mounted a measurable response. LTR who responded to the third dose showed significantly lower anti-Spike IgG levels and neutralizing antibodies than IC. We found that there is less neutralization in LTR compared to IC across all variants. Specifically, the neutralization titers in both groups decrease when encountering the Delta variant, and this decline is even more pronounced with the Omicron variant, compared to the Wuhan variant. Furthermore, we identified that the use of high doses of mycophenolate and advanced age were factors that negatively affected the development of anti-Spike IgG antibodies. Regarding vaccine regimes, the regime viral vector/mRNA/mRNA elicited significantly higher responses in LTR compared to other vaccine schemes. In addition to the recommended and necessary booster doses in this population, strategies that achieve adequate immunization should be evaluated.

Phenotypic and functional analysis of γδ T cells in the pathogenesis of human T-cell lymphotropic virus type 1 infection.

The human T-cell leukemia virus type 1 (HTLV-1) is the cause of serious malignant and inflammatory diseases, including adult T-cell leukemia and lymphoma and tropical spastic paraparesis. The potential protective role of γδ T cells in HTLV-1 infection remains unclear. Here, demonstrate that there is a decrease in the amount of Vγ9Vδ2 T cells in patients with HTLV-1, especially in those with HTLV-1 associated pathologies. This suggests that γδ T cells could be involved in controlling the virus. Indeed, we found that Vγ9Vδ2 T cells, expanded from non-infected individuals, can kill cells expressing the viral proteins HBZ and Tax and this phenotype is reversed in the presence of mevastatin. Cytotoxicity by Vγ9Vδ2 T cells was not associated with an increase of INF-γ production. In sharp contrast, killing by NK cells was reduced by Tax expression. Thus, our study provides initial evidence for a potential protective role of Vγ9Vδ2 T cells against HTLV-1 infection. Therapeutic exploitation of these insights is feasible with current technologies of T-cell therapies and could provide novel tools to prevent and treat HTLV-1-associated malignancies and neurologic complications.

Heterologous adenovirus-vector/messenger RNA regimen is associated with improved severe acute respiratory syndrome coronavirus 2 humoral response in liver transplant recipients.

Knowledge of the immunogenicity of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in liver transplant recipients (LTRs) is mainly limited to messenger RNA (mRNA)-based types. We aimed to evaluate the humoral response in LTRs and to address the use of different doses of mycophenolate (MMF) on the probability of developing anti-spike immunoglobulin G (IgG). In this prospective cohort study, SARS-CoV-2 anti-spike IgG, neutralizing antibodies (NAs), and nucleocapsid protein (N) were evaluated in LTRs and healthy volunteers 21-90 days after receiving the second vaccine dose of either ChAdOx1 (AstraZeneca), rAd26-rAd5 (Sputnik V), inactivated BBIBP-CorV (Sinopharm), or the heterologous combination rAd26/mRNA-1273 (Sputnik V/Moderna). We collected information regarding clinical data and vaccine side effects. After excluding three LTRs due to a positive N test, 120 LTRs and 27 controls were analyzed. No significant differences were found among groups. Overall, 24 (89%) controls and 74 (62%) LTRs were positive for anti-spike IgG (p = 0.007). Among LTRs, those immunized with rAd26/mRNA-1273 presented significantly higher positive serology and NAs when compared with the homologous regimens (91% vs. 55%, p = 0.001; and 1182 IU/ml vs. 446 IU/ml, p = 0.002; respectively). In the multivariate analysis, humoral response was significantly reduced in LTRs who received higher doses of MMF (odds ratio [OR], 0.1; 95% confidence interval [CI], 0.03-0.3; p < 0.001) and with increased BMI (OR, 0.4; 95% CI, 0.2-0.7; p = 0.005); and it was significantly higher in those immunized with rAd26/mRNA-1273 (OR, 13.1; 95% CI, 2.3-72.9; p = 0.003). In LTRs anti-spike IgG concentrations showed a very good correlation with NA titers (R2 = 0.949; 95% CI, 0.919-0.967; p < 0.001). No serious adverse events were reported in either group. Conclusion: In LTRs, rAd26/mRNA-1273 was independently associated with higher antibody response. Future studies are necessary to evaluate whether combining different vaccine platforms and MMF reduction may lead to a better booster response.

Case Report: Relevance of an Accurate Diagnosis and Monitoring of Infective Dermatitis Associated With Human T-Lymphotropic Virus Type 1 in Childhood.

Human T-lymphotropic virus type 1 (HTLV-1) is a neglected retrovirus distributed worldwide and the ethiological agent of several pathologies, such as adult T-cell leukemia/lymphoma (ATLL), a chronic myelopathy known as HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) and infective dermatitis associated with HTLV-1 (IDH). HTLV-1 presents tropism for CD4+ T cells and induces deregulation of the cytokine profile. IDH is a severe, chronic superinfected eczema generally associated with Staphylococcus aureus and/or Streptococcus beta haemolyticus infection that responds partially to antibiotic therapy but prompt recurrence develops upon treatment withdrawal. IDH could be a risk factor for progression toward both HAM/TSP and ATLL and, similarly to other diseases associated with HTLV-1, it is sub-diagnosed particularly in non-endemic areas. Here, we present a case of IDH in a young boy living in Buenos Aires with symptoms since 2010, at the age of 5. HTLV-1 infection was suspected and confirmed in 2016. The patient exhibited chronic dermatosis with exudative eruption involving mainly the scalp, retroauricular regions, neck and abdomen. Clinical evaluations, routine laboratory tests, full blood count, and HTLV-1 diagnosis for this case are included.

Autophagy in Human T-Cell Leukemia Virus Type 1 (HTLV-1) Induced Leukemia.

Viruses play an important role in the development of certain human cancers. They are estimated to contribute 16% to all human cancers. Human T-cell leukemia virus type 1 (HTLV-1) was the first human retrovirus to be discovered and is the etiological agent of adult T-cell leukemia/lymphoma (ATLL), an aggressive T-cell malignancy with poor prognosis. HTLV-1 viral proteins interact with mechanisms and proteins present in host cells for their own benefit, evading the immune system and promoting the establishment of disease. Several viruses manipulate the autophagy pathway to achieve their infective goals, and HTLV-1 is not the exception. HTLV-1 Tax viral protein engages NF-κB and autophagy pathways prone favoring viral replication and T cell transformation. In this review we focus on describing the relationship of HTLV-1 with the autophagy machinery and its implication in the development of ATLL.

[Leukemia associated to human T cell lymphotropic virus type 1 (HTLV-1) infection and intrafamily transmission in Santiago del Estero]. / Leucemia asociada al virus linfotrópico T humano tipo 1 (HTLV-1) y transmisión intrafamiliar de la infección en Santiago del Estero.

Adult T-cell leukemia/lymphoma (ATLL) is an hematological disease caused by human T-cell lymphotropic virus type 1 (HTLV-1) that develops after 20 years of incubation preferentially when the infection is acquired by vertical transmission. In cases of transmission by transfusion or organ transplant, this time is reduced from 3 months to 3 years. Acute ATLL is difficult to diagnose because it is unusual and has a rapid progression to death. In the Argentine Northwest, where the virus is endemic, ATLL is more frequent, however it is also detected continuously in the rest of the country. The treatment of choice, in the first instance, is the combined use of antivirals. We present a case of acute ATLL developed in a 59-year-old man from Santiago del Estero from which intrafamilial transmission of HTLV-1 infection was identified.

La leucemia/linfoma a células T del adulto (ATLL) es una enfermedad hematológica causada por el virus linfotrópico T humano tipo 1 (HTLV-1) que se desarrolla luego de 20 años de incubación, preferencialmente cuando la infección se adquiere por transmisión vertical. Este tiempo se reduce de 3 meses a 3 años cuando la transmisión del virus es por transfusión o trasplante de órganos. La ATLL aguda es de difícil diagnóstico por ser inusual y tener una rápida progresión a la muerte. En el Noroeste argentino, donde el virus es endémico, la ATLL es más frecuente, sin embargo, también se la detecta continuamente en el resto del país. El tratamiento de elección, en primera instancia, es el uso combinado de antivirales. Presentamos un caso de ATLL aguda desarrollada en un hombre de 59 años de Santiago del Estero a partir del cual se identificó transmisión intrafamiliar de la infección por HTLV-1.

Molecular detection of human T-lymphotropic virus type 1 infection among oncology patients in Germany: A retrospective view.

Human T-cell lymphotropic virus (HTLV) belongs to a larger group of primate T-cell lymphotropic viruses (PTLVs) within the family Retroviridae. It is estimated that 10 to 20 million people worldwide may be infected with HTLV-1. Although most of them are asymptomatic, around 5% of infected individuals may develop either HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) or Adult T-cell Leukaemia/Lymphoma (ATLL). Public Health authorities in many countries have implemented routine blood-donor tests for HTLV-specific antibodies; but this is not the case for Germany since the reported prevalence is very low (7/100,000). With the aim to evaluate retrospectively the presence of HTLV-1 among oncology patients in this country, samples stored at the Universitätsklinikum Freiburg, were analyzed. For this purpose, two different nested-PCR (n-PCR) protocols have been modified and set up for HTLV-1 detection. One positive case was detected by n-PCR among 406 samples (0,25%) in a period of 5 years (2008-2012) corresponding to a T-Cell Lymphoma. Despite the low prevalence, this virus is circulating in Germany, probably due to the increasing numbers of immigrants in these last years. Physicians should consider HTLV-1 infection and suspect it taking in account the ethnic and relation to endemic regions regardless the patient's residence.

Leucemia asociada al virus linfotrópico T humano tipo 1 (HTLV-1) y transmisión intrafamiliar de la infección en Santiago del Estero / Leukemia associated to human T cell lymphotropic virus type 1 (HTLV-1) infection and intrafamily transmission in Santiago del Estero

Resumen La leucemia/linfoma a células T del adulto (ATLL) es una enfermedad hematológica causada por el virus linfotrópico T humano tipo 1 (HTLV-1) que se desarrolla luego de 20 años de incubación, preferencialmente cuando la infección se adquiere por transmisión vertical. Este tiempo se reduce de 3 meses a 3 años cuando la transmisión del virus es por transfusión o trasplante de órganos. La ATLL aguda es de difícil diagnóstico por ser inusual y tener una rápida progresión a la muerte. En el Noroeste argentino, donde el virus es endémico, la ATLL es más frecuente, sin embargo, también se la detecta continuamente en el resto del país. El tratamiento de elección, en primera instancia, es el uso combinado de antivirales. Presentamos un caso de ATLL aguda desarrollada en un hombre de 59 años de Santiago del Estero a partir del cual se identificó transmisión intrafamiliar de la infección por HTLV-1.

Abstract Adult T-cell leukemia/lymphoma (ATLL) is an hematological disease caused by human T-cell lymphotropic virus type 1 (HTLV-1) that develops after 20 years of incubation preferentially when the infection is acquired by vertical transmission. In cases of transmission by transfusion or organ transplant, this time is reduced from 3 months to 3 years. Acute ATLL is difficult to diagnose because it is unusual and has a rapid progression to death. In the Argentine Northwest, where the virus is endemic, ATLL is more frequent, however it is also detected continuously in the rest of the country. The treatment of choice, in the first instance, is the combined use of antivirals. We present a case of acute ATLL developed in a 59-year-old man from Santiago del Estero from which intrafamilial transmission of HTLV-1 infection was identified.