Elevated maternal corticosterone during lactation hinders the neonatal adaptive immune response to herpes simplex virus (HSV) infection

Prevalence and clinical markers of herpes simplex virus infection in oral lesions of bullous pemphigoid

Background

The manifestations of bullous pemphigoid (BP) and herpes simplex virus (HSV) infection are similar in oral mucosa, and the laboratory detection of HSV has some limitations, making it difficult to identify the HSV infection in oral lesions of BP. In addition, the treatments for BP and HSV infection have contradictory aspects. Thus, it is important to identify the HSV infection in BP patients in time.

Objective

To identify the prevalence and clinical markers of HSV infection in oral lesions of BP.

Methods

This prospective cross-sectional descriptive analytical study was conducted on 42 BP patients with oral lesions. A total of 32 BP patients without oral lesions and 41 healthy individuals were enrolled as control groups. Polymerase chain reaction was used to detect HSV. Clinical and laboratory characteristics of patients with HSV infection were compared with those without infection.

Results

A total of 19 (45.2%) BP patients with oral lesions, none (0.0%) BP patients without oral lesions, and four (9.8%) healthy individuals were positive for HSV on oral mucosa. Among BP patients with oral lesions, the inconsistent activity between oral and skin lesions (p=0.001), absence of blister/blood blister in oral lesions (p=0.020), and pain for oral lesions (p=0.014) were more often seen in HSV-positive than HSV-negative BP patients; the dosage of glucocorticoid (p=0.023) and the accumulated glucocorticoid dosage in the last 2 weeks (2-week AGC dosage) (p=0.018) were higher in HSV-positive BP patients. Combining the above five variables as test variable, the AUC was 0.898 (p<0.001) with HSV infection as state variable in ROC analysis. The absence of blister/blood blister in oral lesions (p=0.030) and pain for oral lesions (p=0.038) were found to be independent predictors of HSV infection in multivariable analysis. A total of 14 (73.7%) HSV-positive BP patients were treated with 2-week famciclovir and the oral mucosa BPDAI scores significantly decreased (p<0.001).

Conclusion

HSV infection is common in BP oral lesions. The inconsistent activity between oral and skin lesions, absence of blister in oral lesions, pain for oral lesions, higher currently used glucocorticoid dosage, and higher 2-week AGC dosage in BP patients should alert physicians to HSV infection in oral lesions and treat them with 2-week famciclovir in time.

Stress Hormones Epinephrine and Corticosterone Selectively Reactivate HSV-1 and HSV-2 in Sympathetic and Sensory Neurons

Herpes simplex viruses 1 and 2 (HSV-1 and HSV-2) establish latency in sensory and autonomic neurons, from which they can reactivate to cause recurrent disease throughout the life of the host. Stress is strongly associated with HSV recurrences in humans and animal models. However, the mechanisms through which stress hormones act on the latent virus to cause reactivation are unknown. We show that the stress hormones epinephrine (EPI) and corticosterone (CORT) induce HSV-1 reactivation selectively in sympathetic neurons, but not sensory or parasympathetic neurons. Activation of multiple adrenergic receptors is necessary for EPI-induced HSV-1 reactivation, while CORT requires the glucocorticoid receptor. In contrast, CORT, but not EPI, induces HSV-2 reactivation in both sensory and sympathetic neurons through either glucocorticoid or mineralocorticoid receptors. Reactivation is dependent on different transcription factors for EPI and CORT, and coincides with rapid changes in viral gene expression, although genes differ for HSV-1 and HSV-2, and temporal kinetics differ for EPI and CORT. Thus, stress-induced reactivation mechanisms are neuron-specific, stimulus-specific and virus-specific. These findings have implications for differences in HSV-1 and HSV-2 recurrent disease patterns and frequencies, as well as development of targeted, more effective antivirals that may act on different responses in different types of neurons.

Behavioral Deficits in Juveniles Mediated by Maternal Stress Hormones in Mice

Maternal depression has been shown to negatively impact offspring development. Investigation into the impact of maternal depression and offspring behavior has relied on correlative studies in humans. Further investigation into the underlying mechanisms has been hindered by the lack of useful animal models. We previously characterized a mouse model which exhibits depression-like behaviors restricted to the postpartum period and abnormal/fragmented maternal care (Gabrd^−/− mice). Here we utilized this unique mouse model to investigate the mechanism(s) through which maternal depression-like behaviors adversely impact offspring development. Cross-fostering experiments reveal increased anxiety-like and depression-like behaviors in mice reared by Gabrd^−/− mothers. Wild type and Gabrd^−/− mice subjected to unpredictable stress during late pregnancy exhibit decreased pup survival and depression-like behavior in the postpartum period. Exogenous corticosterone treatment in wild type mice during late pregnancy is sufficient to decrease pup survival and induce anxiety-like and depression-like behaviors in the offspring. Further, the abnormal behaviors in juvenile mice reared by Gabrd^−/− mice are alleviated by treatment of the mothers with the corticotropin-releasing hormone (CRH) antagonist, Antalarmin. These studies suggest that hyperresponsiveness of the HPA axis is associated with postpartum depression and may mediate the adverse effects of maternal depression on offspring behavior.

Maternal care interacts with prenatal stress in altering sexual dimorphism in male rats

The present study analyzes the interaction between prenatal stress and mother's behavior on brain, hormonal, and behavioral development of male offspring in rats. It extends to males our previous findings, in females, that maternal care can alter behavioral dimorphism that becomes evident in the neonates when they mature. Experiment 1 compares the maternal behavior of foster mothers toward cross-fostered pups versus mothers rearing their own litters. Experiment 2 ascertains the induced "maternal" behavior of the male pups, derived from Experiment 1 when they reached maturity. The most striking effect was that the males non-exposed to the stress as fetuses and raised by stressed foster mothers showed the highest levels of "maternal" behavior of all the groups (i.e., induction of maternal behavior and retrieving behavior), not differing from the control, unstressed, female groups. Furthermore, those males showed significantly fewer olfactory bulb mitral cells than the control males that were non-stressed as fetuses and raised by their own non-stressed mothers. They also presented the lowest levels of plasma testosterone of all the male groups. The present findings provide evidence that prenatal environmental stress can "demasculinize" the behavior, brain anatomy and hormone secretion in the male fetuses expressed when they reach maturity. Moreover, the nature of the maternal care received by neonates can affect the behavior and physiology that they express at maturity.

Normal maternal behavior, but increased pup mortality, in conditional oxytocin receptor knockout females

Oxytocin (Oxt) and the Oxt receptor (Oxtr) are implicated in the onset of maternal behavior in a variety of species. Recently, we developed two Oxtr knockout lines: a total body knockout (Oxtr-/-) and a conditional Oxtr knockout (OxtrFB/FB) in which the Oxtr is lacking only in regions of the forebrain, allowing knockout females to potentially nurse and care for their biological offspring. In the current study, we assessed maternal behavior of postpartum OxtrFB/FB females toward their own pups and maternal behavior of virgin Oxtr-/- females toward foster pups and compared knockouts of both lines to wildtype (Oxtr+/+) littermates. We found that both Oxtr-/- and OxtrFB/FB females appear to have largely normal maternal behaviors. However, with first litters, approximately 40% of the OxtrFB/FB knockout dams experienced high pup mortality, compared to fewer than 10% of the Oxtr+/+ dams. We then went on to test whether or not this phenotype occurred in subsequent litters or when the dams were exposed to an environmental disturbance. We found that regardless of the degree of external disturbance, OxtrFB/FB females lost more pups on their first and second litters compared to wildtype females. Possible reasons for higher pup mortality in OxtrFB/FB females are discussed.

Antimicrobial anxiety: the impact of stress on antimicrobial immunity

Leukocytes and epithelial cells are fundamental to antimicrobial immunity. Their antimicrobial responses are an evolutionarily conserved component of the innate immune system and are influenced by the host's response to external stimuli. The efficacy of host defense via antimicrobial responses derives from the ability of AMPs to rapidly identify and eradicate foreign microbes and activate proinflammatory pathways, and from the capacity of later innate and adaptive immune responses to amplify protection through distinct biochemical mechanisms. Recent advances in neuroimmunology have identified a direct link between the neuroendocrine and immune systems, where environmental stimuli are generally believed to promote a transient effect on the immune system in response to environmental challenges and are presumably brought back to baseline levels via neuroendocrine pathways. Stress is an environmental stimulus that flares from a variety of circumstances and has become engrained in human society. Small bouts of stress are believed to enhance the host's immune response; however, prolonged periods of stress can be detrimental through excess production of neuroendocrine-derived mediators that dampen immune responses to invasive pathogens. Elucidation of the mechanisms behind stress-induced immune modulation of antimicrobial responses will ultimately lead to the development of more effective therapeutic interventions for pathologic conditions. It is the intent of this review to broaden the existing paradigm of how stress-related molecules dampen immune responses through suppression of antimicrobial mechanisms, and to emphasize that bacteria can use these factors to enhance microbial pathogenesis during stress.

Opioid growth factor suppresses expression of experimental autoimmune encephalomyelitis

Naltrexone, an opioid antagonist, has been shown to modulate expression of experimental autoimmune encephalomyelitis (EAE), an animal model of MS, suggesting that endogenous opioids are inhibitory trophic factors in EAE. In the present study, we investigated the effects of one native opioid peptide, opioid growth factor ([Met(5)]-enkephalin), on the onset and progression of EAE. C57Bl/6 mice injected with myelin oligodendrocyte glycoprotein (MOG) received daily injections of 10 mg/kg OGF (MOG+OGF) or saline (MOG+Vehicle). Over 60% of the MOG+OGF animals did not exhibit behavioral signs of disease (EAE) in contrast to 100% of the mice in the MOG+Vehicle group. The severity and disease indices of EAE in the OGF-treated mice were markedly reduced from MOG+Vehicle cohorts. By day 30, 60% of MOG+OGF mice had a remission, relative to 4% in the MOG+Vehicle group. MOG-injected mice receiving OGF had significant reductions in activated astrocytes and damaged neurons compared to MOG+Vehicle animals. Unlike MOG+Vehicle and MOG+OGF mice with behavioral signs of disease, MOG+OGF animals without manifestation of disease had no lumbar spinal cord demyelination. Both OGF and OGF receptor were detected in splenic-derived T lymphocytes by immunohistochemistry. OGF treatment decreased both DNA synthesis and cell proliferation in comparison to vehicle-treated T cell lymphocyte cultures. These results indicate that an endogenous opioid, OGF, inhibits the onset and progression of EAE, and suggest that clinical studies on the use of OGF treatment for MS are merited.

Phenotype and function of neonatal DC

Newborns face complex physical and immunological changes before and after birth. Although the uterus is a sterile environment for the fetus, it also contains non-self material from the mother. Birth involves the transition from the sterile intra-uterine environment to an environment rich in microbes and requires rapid induction of appropriate responses to control these microbes. In this review we focus on the similarities and differences of human and murine neonatal DC and their reaction to various stimuli. A better understanding of the newborn immune system--in particular, the DC-T-cell interaction--will be beneficial for the development of improved strategies to prevent or treat infections in this vulnerable population and prepare the immune system to cope with allergens and tumors later in life.