A scoping review of regulatory T cell dynamics in convalescent COVID-19 patients – indications for their potential involvement in the development of Long COVID?

BackgroundRecovery from coronavirus disease 2019 (COVID-19) can be impaired by the persistence of symptoms or new-onset health complications, commonly referred to as Long COVID. In a subset of patients, Long COVID is associated with immune system perturbations of unknown etiology, which could be related to compromised immunoregulatory mechanisms.ObjectiveThe objective of this scoping review was to summarize the existing literature regarding the frequency and functionality of Tregs in convalescent COVID-19 patients and to explore indications for their potential involvement in the development of Long COVIDDesignA systematic search of studies investigating Tregs during COVID-19 convalescence was conducted on MEDLINE (via Pubmed) and Web of Science.ResultsThe literature search yielded 17 relevant studies, of which three included a distinct cohort of patients with Long COVID. The reviewed studies suggest that the Treg population of COVID-19 patients can reconstitute quantitatively and functionally during recovery. However, the comparison between recovered and seronegative controls revealed that an infection-induced dysregulation of the Treg compartment can be sustained for at least several months. The small number of studies investigating Tregs in Long COVID allowed no firm conclusions to be drawn about their involvement in the syndrome’s etiology. Yet, even almost one year post-infection Long COVID patients exhibit significantly altered proportions of Tregs within the CD4+ T cell population.ConclusionsPersistent alterations in cell frequency in Long COVID patients indicate that Treg dysregulation might be linked to immune system-associated sequelae. Future studies should aim to address the association of Treg adaptations with different symptom clusters and blood parameters beyond the sole quantification of cell frequencies while adhering to consensualized phenotyping strategies

A scoping review of regulatory T cell dynamics in convalescent COVID-19 patients – indications for their potential involvement in the development of Long COVID?

Background Recovery from coronavirus disease 2019 (COVID-19) can be impaired by the persistence of symptoms or new-onset health complications, commonly referred to as Long COVID. In a subset of patients, Long COVID is associated with immune system perturbations of unknown etiology, which could be related to compromised immunoregulatory mechanisms. Objective The objective of this scoping review was to summarize the existing literature regarding the frequency and functionality of Tregs in convalescent COVID-19 patients and to explore indications for their potential involvement in the development of Long COVID Design A systematic search of studies investigating Tregs during COVID-19 convalescence was conducted on MEDLINE ( via Pubmed) and Web of Science. Results The literature search yielded 17 relevant studies, of which three included a distinct cohort of patients with Long COVID. The reviewed studies suggest that the Treg population of COVID-19 patients can reconstitute quantitatively and functionally during recovery. However, the comparison between recovered and seronegative controls revealed that an infection-induced dysregulation of the Treg compartment can be sustained for at least several months. The small number of studies investigating Tregs in Long COVID allowed no firm conclusions to be drawn about their involvement in the syndrome’s etiology. Yet, even almost one year post-infection Long COVID patients exhibit significantly altered proportions of Tregs within the CD4+ T cell population. Conclusions Persistent alterations in cell frequency in Long COVID patients indicate that Treg dysregulation might be linked to immune system-associated sequelae. Future studies should aim to address the association of Treg adaptations with different symptom clusters and blood parameters beyond the sole quantification of cell frequencies while adhering to consensualized phenotyping strategies

HIV First Diagnoses in Germany in 2014-A Regional Analysis

Background Information on testing units in health care is scarce, particularly the group of late-presenters among the HIV-first diagnoses is still a challenge in Germany. Aim Analysis of the impact of testing units on and reasons for the prevalence of HIV-first diagnoses and late presentation, taking 2014 for illustrative purposes. Material and Methods Cross-sectional analysis of all individuals, treated in the Network HIV-Regional who were first diagnosed with HIV in 2014; patient characteristics, demographic and clinical data, including information on HIV testing were collected retrospectively and in a decentralised manner, pseudonymized and statistically evaluated. Results A total of 971 individuals with HIV-first diagnosis from 31 specialised care centres throughout Germany (15 hospitals, 16 private practices) represented 27.5% of all National HIV-first diagnoses -registrations from Robert Koch Institute for 2014, with similar results for CD4-cell count and HIV-transmission risk. The most common test site was a hospital (34.8%), followed by the office of a family doctor (19.6%) and medical specialist (16.1%). If the first diagnosis was established in hospital, then the patients were on average older than those tested on an ambulant care basis (42 vs. 37 years, p=0.001); moreover, the HI-viral load was higher (585 vs. 270 thousand copies/mL, p<0.001) and the CD4-cell count lower (265 vs. 414/mu L, p<0.001). In 208/971 individuals with first diagnosis, at least one AIDS-defining disease was found, most frequently pneumocystis-pneumonia (43.8%), candidiasis (36.5%) and Kaposi sarcoma (10.6%). A regional comparison revealed that in eastern Germany, for first diagnosed HIV-patients were younger, had a higher HIV-RNA viral load and also more often clinical AIDS. Conclusion This analysis of HIV-Regional for 2014 enables a deeper insight into HIV first diagnoses, on the eve of the introduction of important prevention tools in Germany, e. g., HIV home testing and pre-exposure prophylaxis. This cross-sectional analysis was representative for Germany and underscores the importance of specialised hospitals, in particular for eastern Germany, and furthermore the involvement of late-presenters into HIV health care

Preservation of egg morphology after incubation with different fixatives and KOH concentrations.

<p>Incubation of 70% ethanol-fixed placental tissue (A) or naive placental tissue (B) and infected mouse liver with 4% KOH for 24h at 37°C. Mouse liver pieces incubated alone with 4% KOH (C) or 10% KOH (D) served as controls. In all groups incubated with 4% KOH the eggshells of nearly all eggs of <i>S</i>. <i>mansoni</i> were intact and the lateral spine was easy to identify. The eggs contained a more or less developed miracidium or were without any content. <i>S</i>. <i>mansoni</i> eggs in the 10% KOH control group were nearly completely digested. The morphology and the lateral spine were hard to identify.</p