PD-1 Receptor (+) T cells are associated with the efficacy of the combined treatment with regulatory t cells and rituximab in type 1 diabetes children via regulatory t cells suppressive activity amelioration

An imbalance between exaggerated autoaggressive T cell responses, primarily CD8 + T cells, and impaired tolerogenic mechanisms underlie the development of type 1 diabetes mellitus. Disease-modifying strategies, particularly immunotherapy focusing on FoxP3 + T regulatory cells (Treg), and B cells facilitating antigen presentation for T cells, show promise. Selective depletion of B cells may be achieved with an anti-CD20 monoclonal antibody (mAb). In a 2-year-long flow cytometry follow-up, involving 32 peripheral blood T and B cell markers across three trial arms (Treg + rituximab N = 12, Treg + placebo N = 13, control N = 11), we observed significant changes. PD-1 receptor (+) CD4 + Treg, CD4 + effector T cells (Teffs), and CD8 + T cell percentages increased in the combined regimen group by the end of follow-up. Conversely, the control group exhibited a notable reduction in PD-1 receptor (+) CD4 + Teff percentages. Considering clinical endpoints, higher PD-1 receptor (+) expression on T cells correlated with positive responses, including a higher mixed meal tolerance test AUC, and reduced daily insulin dosage. PD-1 receptor (+) T cells emerged as a potential therapy outcome biomarker. In vitro validation confirmed that successful Teff suppression was associated with elevated PD-1 receptor (+) Treg levels. These findings support PD-1 receptor (+) T cells as a reliable indicator of treatment with combined immunotherapy consisting of Tregs and anti-CD20 mAb efficacy in type 1 diabetes mellitus.

Correlation of ENT Symptoms with Age, Sex, and Anti-SARS-CoV-2 Antibody Titer in Plasma

Our objective is to evaluate the correlation between ENT symptom occurrence and antibody titer in convalescent plasma, as well as the influence of age and gender on ENT manifestations of COVID-19. We measured the levels of antibodies in 346 blood donors, who had PCR-confirmed previous infection and met the study inclusion criteria. We recorded otolaryngological symptoms during infection: dry cough, dyspnea, sore throat, smell/taste disturbances, vertigo, dizziness, nausea and vomiting, sudden unilateral loss of hearing, progressive loss of hearing, and tinnitus. In addition, we statistically analyzed the correlation between patients' antibody levels, symptoms, age, and gender using a chi-square test or Fisher exact test. A p-value less than 0.05 determined statistical significance. The mean age of the convalescents was 39.8 ± 9.56 SD and the median of the measured anti-SARS-CoV2 plasma antibodies was 1:368.5. The most common ENT symptoms were smell/taste disturbances (62.43%), dry cough (40.46%), sore throat (24.86%), and dyspnea (23.7%). Smell and taste disturbances were more frequent in younger patients and the marked antibody titer was lower, which was contrary to a higher antibody titer associated with dry cough, dyspnea, and dizziness. Occurrence of sore throat was not correlated with age, sex, or antibody level. There were no significant differences in otological symptoms in female patients. Gender does not affect the occurrence of ENT symptoms. The symptomatic course of SARS-CoV-2 infection is not always associated with higher levels of antibodies in the blood. The age of the infected patients, unlike gender, affects the occurrence of some ENT symptoms.

Combined therapy with CD4+ CD25highCD127- T regulatory cells and anti-CD20 antibody in recent-onset type 1 diabetes is superior to monotherapy: Randomized phase I/II trial

AIMS

Monotherapy with autologous expanded CD4⁺ CD25^high CD127^- T regulatory cells (Tregs) or rituximab has been documented to slow disease progression in patients with recent-onset type 1 diabetes mellitus (T1DM). Whether a combined therapy including both drugs would further benefit this patient population is unknown.

MATERIALS AND METHODS

We conducted a three-arms clinical trial to explore the efficacy and safety of the combined treatment with Tregs and rituximab in paediatric patients with T1DM. The patients were allocated to three groups: Tregs only (n = 13), Tregs + rituximab (n = 12) and control (n = 11). The key primary efficacy analyses were C-peptide levels (mixed meal tolerance test) and the proportion of patients in remission at 12 and 24 months.

RESULTS

At month 24, as compared with the control, both treatment groups remained superior in the area under the curve of C-peptide mixed meal tolerance test, whereas in the analysis of all visits only the combined therapy improved area under the curve at 12 and 24 months. The proportion of patients in remission was significantly higher in the combined group than in the control group at 3, 6, 9 and 21 months but not at 18 and 24 months. There was no significant difference between the Tregs only group and control group. Adverse events occurred in 80% patients, mostly in the combined group and Tregs only group. No adverse events led to the withdrawal of the intervention or death. All comparisons were performed with alpha level of 5%.

CONCLUSIONS

Over 2 years, combined therapy with Tregs and rituximab was consistently superior to monotherapy in delaying T1DM progression in terms of C-peptide levels and the maintenance of remission.

Assessment of anti-SARS-CoV-2 antibodies level in convalescents plasma

Despite extensive vaccination, the quantity of patients infected with the SARS-CoV-2 virus and its variants continues to grow worldwide. Treating patients with a severe course of COVID-19 is a difficult challenge. One of the generally accepted and specific therapy methods is the use of plasma rich in anti-SARS-CoV-2 antibodies. On the other hand, assessing the antibodies level depending on the time after infection allows for vaccine-decision. The study marked the level of anti-SARS-CoV-2 IgG antibodies in 351 COVID-19 convalescent residents of one geographical region in Poland. The study group included blood donors. The studies were cross-sectional and extended to a questionnaire to determine infection severity. These data were compiled statistically. The study considered epidemiological factors, the time from the end of the infection, and infection severity. The fastest increase of the antibodies level was observed up to 59 days after COVID-19, and it was statistically significantly higher among men. Higher levels of antibodies were found among people above the average age in both men and women. There was an increase in the level of antibodies since the onset of the disease in men, while in women, it decreased. The antibodies level was also found to depend on the severity of the course of COVID-19 infection. The optimal group of plasma donors in the studied geographical region is men and women above 39 years old. after a more severe infection. The titer of antibodies increases with time from the disease.

Proinsulin-specific T regulatory cells may control immune responses in type 1 diabetes: implications for adoptive therapy

OBJECTIVE

Here we looked for possible mechanisms regulating the progression of type 1 diabetes mellitus (T1DM). In this disease, autoaggressive T cells (T conventional cells, Tconvs) not properly controlled by T regulatory cells (Tregs) destroy pancreatic islets.

RESEARCH DESIGN AND METHODS

We compared the T-cell compartment of patients with newly diagnosed T1DM (NDT1DM) with long-duration T1DM (LDT1DM) ones. The third group consisted of patients with LDT1DM treated previously with polyclonal Tregs (LDT1DM with Tregs). We have also looked if the differences might be dependent on the antigen specificity of Tregs expanded for clinical use and autologous sentinel Tconvs.

RESULTS

Patients with LDT1DM were characterized by T-cell immunosenescence-like changes and expansion of similar vβ/T-cell receptor (TCR) clones in Tconvs and Tregs. The treatment with Tregs was associated with some inhibition of these effects. Patients with LDT1DM possessed an increased percentage of various proinsulin-specific T cells but not GAD65-specific ones. The percentages of all antigen-specific subsets were higher in the expansion cultures than in the peripheral blood. The proliferation was more intense in proinsulin-specific Tconvs than in specific Tregs but the levels of some proinsulin-specific Tregs were exceptionally high at baseline and remained higher in the expanded clinical product than the levels of respective Tconvs in sentinel cultures.

CONCLUSIONS

T1DM is associated with immunosenescence-like changes and reduced diversity of T-cell clones. Preferential expansion of the same TCR families in both Tconvs and Tregs suggests a common trigger/autoantigen responsible. Interestingly, the therapy with polyclonal Tregs was associated with some inhibition of these effects. Proinsulin-specific Tregs appeared to be dominant in the immune responses in patients with T1DM and probably associated with better control over respective autoimmune Tconvs.

TRIAL REGISTRATION NUMBER

EudraCT 2014-004319-35.

Factors affecting long-term efficacy of T regulatory cell-based therapy in type 1 diabetes

Background

Recent studies suggest that immunotherapy using T regulatory cells (Tregs) prolongs remission in type 1 diabetes (T1DM). Here, we report factors that possibly affect the efficacy of this treatment.

Methods

The metabolic and immune background of 12 children with recently diagnosed T1DM, as well as that of untreated subjects, during a 2-year follow-up is presented. Patients were treated with up to 30 × 10⁶/kg b.w. of autologous expanded CD3⁺CD4⁺CD25^highCD127⁻ Tregs.

Results

The disease progressed and all patients were insulin-dependent 2 years after inclusion. The β-cell function measured by c-peptide levels and the use of insulin were the best preserved in patients treated with two doses of Tregs (3/6 in remission), less so after one dose (1/6 in remission) and the worst in untreated controls (no remissions). Increased levels of Tregs could be seen in peripheral blood after their adoptive transfer together with the shift from naïve CD62L⁺CD45RA⁺ to memory CD62L⁺CD45RA⁻ Tregs. Increasing serum levels of proinflammatory cytokines were found: IL6 increased in all subjects, while IL1 and TNFα increased only in untreated group. Therapeutic Tregs were dependent on IL2, and their survival could be improved by other lymphocytes.

Conclusions

The disease progression was associated with changing proportions of naïve and memory Tregs and slowly increasing proinflammatory activity, which was only partially controlled by the administered Tregs. The therapeutic cells were highly dependent on IL2. We conclude that the therapy should be administered at the earliest to protect the highest possible mass of islets and also to utilize the preserved content of Tregs in the earlier phases of T1DM.

Trial registrationhttp://www.controlled-trials.com/ISRCTN06128462; registered retrospectively

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-016-1090-7) contains supplementary material, which is available to authorized users.