Screening for affective dysregulation in school-aged children: relationship with comprehensive measures of affective dysregulation and related mental disorders.

Affective dysregulation (AD) is characterized by irritability, severe temper outbursts, anger, and unpredictable mood swings, and is typically classified as a transdiagnostic entity. A reliable and valid measure is needed to adequately identify children at risk of AD. This study sought to validate a parent-rated screening questionnaire, which is part of the comprehensive Diagnostic Tool for Affective Dysregulation in Children (DADYS-Screen), by analyzing relationships with comprehensive measures of AD and related mental disorders in a community sample of children with and without AD. The sample comprised 1114 children aged 8-12 years and their parents. We used clinical, parent, and child ratings for our analyses. Across all raters, the DADYS-Screen showed large correlations with comprehensive measures of AD. As expected, correlations were stronger for measures of externalizing symptoms than for measures of internalizing symptoms. Moreover, we found negative associations with emotion regulation strategies and health-related quality of life. In receiver operating characteristic (ROC) analyses, the DADYS-Screen adequately identified children with AD and provided an optimal cut-off. We conclude that the DADYS-Screen appears to be a reliable and valid measure to identify school-aged children at risk of AD.

Impact of the COVID-19 pandemic on children with and without affective dysregulation and their families.

Analyzing COVID-19-related stress in children with affective dysregulation (AD) seems especially interesting, as these children typically show heightened reactivity to potential stressors and an increased use of maladaptive emotion regulation strategies. Children in out-of-home care often show similar characteristics to those with AD. Since COVID-19 has led to interruptions in psychotherapy for children with mental health problems and to potentially reduced resources to implement treatment strategies in daily life in families or in out-of-home care, these children might show a particularly strong increase in stress levels. In this study, 512 families of children without AD and 269 families of children with AD reported on COVID-19-related stress. The sample comprised screened community, clinical, and out-of-home care samples. Sociodemographic factors, characteristics of child and caregiver before the pandemic, and perceived change in external conditions due to the pandemic were examined as potential risk or protective factors. Interestingly, only small differences emerged between families of children with and without AD or between subsamples: families of children with AD and families in out-of-home care were affected slightly more, but in few domains. Improvements and deteriorations in treatment-related effects balanced each other out. Overall, the most stable and strongest risk factor for COVID-19-related stress was perceived negative change in external conditions-particularly family conditions and leisure options. Additionally, caregiver characteristics emerged as risk factors across most models. Actions to support families during the pandemic should, therefore, facilitate external conditions and focus on caregiver characteristic to reduce familial COVID-19-related stress. Trial registration: German Clinical Trials Register (DRKS), ADOPT Online: DRKS00014963 registered 27 June 2018, ADOPT Treatment: DRKS00013317 registered 27 September 2018, ADOPT Institution: DRKS00014581 registered 04 July 2018.

Enhancement of DNA vaccine potency by electroporation in vivo.

The potential of electric current-mediated delivery technology to enhance DNA delivery and DNA vaccine potency was evaluated. Higher levels of reporter gene expression were observed in muscle cells of mice inoculated with luciferase or beta-galactosidase DNA followed by the application of electrical current, compared with DNA injected with no current. Similarly, substantially higher levels of immune responses (up to 20-fold) were demonstrated in mice vaccinated with HIV gag DNA and electric current. These enhanced responses were observed after one or two inoculations, and were maintained for at least 12 weeks. Therefore, the present studies demonstrate the utility of electroporation for enhancement of DNA vaccine potency in animals.

Distribution of DNA vaccines determines their immunogenicity after intramuscular injection in mice.

Intramuscular injection of DNA vaccines elicits potent humoral and cellular immune responses in mice. However, DNA vaccines are less efficient in larger animal models and humans. To gain a better understanding of the factors limiting the efficacy of DNA vaccines, we used fluorescence-labeled plasmid DNA in mice to 1) define the macroscopic and microscopic distribution of DNA after injection into the tibialis anterior muscle, 2) characterize cellular uptake and expression of DNA in muscle and draining lymph nodes, and 3) determine the effect of modifying DNA distribution and cellular uptake by volume changes or electroporation on the magnitude of the immune response. Injection of a standard 50-microl dose resulted in the rapid dispersion of labeled DNA throughout the muscle. DNA was internalized within 5 min by muscle cells near the injection site and over several hours by cells that were located along muscle fibers and in the draining lymph nodes. Histochemical staining and analysis of mRNA expression in isolated cells by RT-PCR showed that the transgene was detectably expressed only by muscle cells, despite substantial DNA uptake by non-muscle cells. Reduction of the injection volume to 5 microl resulted in substantially less uptake and expression of DNA by muscle cells, and correspondingly lower immune responses against the transgene product. However, expression and immunogenicity were restored when the 5-microl injection was followed by electroporation in vivo. These findings indicate that distribution and cellular uptake significantly affect the immunogenicity of DNA vaccines.

Increased DNA vaccine delivery and immunogenicity by electroporation in vivo.

DNA vaccines have been demonstrated to be potent in small animals but are less effective in primates. One limiting factor may be inefficient uptake of DNA by cells in situ. In this study, we evaluated whether cellular uptake of DNA was a significant barrier to efficient transfection in vivo and subsequent induction of immune responses. For this purpose, we used the technique of electroporation to facilitate DNA delivery in vivo. This technology was shown to substantially increase delivery of DNA to cells, resulting in increased expression and elevated immune responses. The potency of a weakly immunogenic hepatitis B surface Ag DNA vaccine was increased in mice, as seen by a more rapid onset and higher magnitude of anti-hepatitis B Abs. In addition, the immunogenicity of a potent HIV gag DNA vaccine was increased in mice, as seen by higher Ab titers, a substantial reduction in the dose of DNA required to induce an Ab response, and an increase in CD8+ T cell responses. Finally, Ab responses were enhanced by electroporation against both components of a combination HIV gag and env DNA vaccine in guinea pigs and rabbits. Therefore, cellular uptake of DNA is a significant barrier to transfection in vivo, and electroporation appears able to overcome this barrier.

Relative potency of cellular and humoral immune responses induced by DNA vaccination.

DNA vaccines can prime broad-based immune responses in small animal models. In the present study, we sought to evaluate the relative ability of DNA vaccines to induce humoral and cellular immune responses. Using a DNA vaccine encoding HIV gag in mice, we observed that CD8+ T cell responses were primed more readily than were antibody responses, particularly at low doses of DNA. These CD8+ T cell responses were detected in spleen cells, as well as at local sites such as the lung and draining lymph nodes. The potency of the HIV gag DNA vaccine used was sufficient to prime strong CTL responses in macaques, but only low to undetectable antibody responses. Therefore, DNA vaccines appear able to prime strong, broad CTL but only modest antibody responses. These results may have implications on the development of vaccines against infectious diseases where both CTL and antibody responses are desired, such as HIV.

Limited antibody-dependent cellular cytotoxicity antibody response induced by a herpes simplex virus type 2 subunit vaccine.

The humoral response to a herpes simplex virus (HSV) type 2 subunit vaccine containing recombinant glycoproteins B (gB2) and D (gD2) was tested in 3 groups of patients. These included HSV-seronegative, HSV-1-seropositive, and HSV-2-seropositive individuals. There were excellent antibody responses, as measured by gB2- and gD2-specific ELISAs and HSV-2 neutralization assays. However, in 2 HSV-2 antibody-dependent cellular cytotoxicity (ADCC) assays, there were relatively low antibody responses, especially among HSV-seronegative individuals. The low ADCC responses may be associated with the poor efficacy of this vaccine observed in clinical trials.

Intranasal immunization with recombinant gD2 reduces disease severity and mortality following genital challenge with herpes simplex virus type 2 in guinea pigs.

The ability of a genetically detoxified mutant of heat labile enterotoxin (LTK63) to act as a mucosal adjuvant following intranasal immunization with recombinant gD2 has previously been reported in mice [Ugozzoli M, O'Hagan DT, Ott GS. Intranasal immunization of mice with herpes simplex virus type 2 recombinant gD2: the effect of adjuvants on mucosal and serum antibody responses. Immunol 1998;93:563-571.]. In the current studies, these observations were extended to the guinea pig model. Immunized guinea pigs were subsequently challenged intravaginally with HSV-2. Intranasal immunization with gD2 and LTK63 induced a significant reduction in disease severity and a reduction in mortality. However, only intramuscular immunization with a potent adjuvant (MF59) induced protection against the incidence of disease.

The influence of adjuvant on the therapeutic efficacy of a recombinant genital herpes vaccine.

The potential use of vaccines for treatment of chronic or persistent virus infections is an area of great interest and controversy. Previous experiments have shown that the incidence and severity of spontaneous recurrent genital herpes in latently infected guinea pigs could be significantly reduced by vaccination with herpes simplex virus glycoprotein subunit vaccines. The current study shows the critical role of adjuvant in an effective formulation. Immunization of previously infected guinea pigs with a subunit vaccine containing a muramyl peptide derivative, MTP-PE, in a low-oil emulsion as adjuvant reduced the incidence of recurrent disease up to 80% compared with formulations lacking MPT-PE. Vaccines containing adjuvant alone failed to modify recurrences. Alum, the traditional adjuvant, was not effective. Glycoprotein subunit vaccines elicited high-titer ELISA and neutralizing antibody responses far greater than those generated by virus infection. However, neither antibody titers nor lymphoproliferative responses reproducibly correlated with the pattern of recurrent disease.