Development and initial validation of a Swedish inventory to screen for symptoms of deficient perineum in women after vaginal childbirth: 'Karolinska Symptoms After Perineal Tear Inventory'.

BACKGROUND: Perineal tears are common after vaginal birth and may result in pelvic floor symptoms. However, there is no validated questionnaire that addresses long-term symptoms in women with a deficient perineum after vaginal birth. Thus, the objective of this study was to develop and psychometrically evaluate a clinical screening inventory that estimates subjective symptoms in women with a deficient perineum more than one year after vaginal delivery. MATERIAL AND METHODS: The development and psychometric evaluation employed both qualitative and quantitative methods. Qualitative strategies involved content validity and Think Aloud protocol for generation of items. The psychometric evaluation employed principal component analysis to reduce the number of items. The inventory was completed by women with persistent symptoms after perineal tears (N = 170). Results were compared to those of primiparous women giving birth by caesarean section (N = 54) and nulliparous women (N = 338). RESULTS: A preliminary 41-item inventory was developed, and the psychometric evaluation resulted in a final 11-item inventory. Women with confirmed deficient perineum after perineal trauma scored significantly higher on the symptoms inventory than women in control groups. A cut-off value of ≥ 8 could distinguish patients from controls with high sensitivity (100%) and specificity (87-91%). CONCLUSIONS: The Karolinska Symptoms After Perineal Tear Inventory, is a psychometrically valid 11-item patient-reported outcome measure for symptoms of deficient perineum more than one year after vaginal birth. More research is needed to validate the inventory in various patient populations as well as its use in pelvic floor interventions. The inventory has the potential to improve patient counseling and care in the future.

Mindfulness-based cognitive therapy (MBCT) in patients with obsessive-compulsive disorder (OCD) and residual symptoms after cognitive behavioral therapy (CBT): a randomized controlled trial.

Up to one-third of individuals with obsessive-compulsive disorder (OCD) do not benefit from evidence-based psychotherapy. We examined the efficacy of mindfulness-based cognitive therapy (MBCT) as a complementary treatment option. In a prospective, bicentric, assessor-blinded, randomized, and actively controlled clinical trial, 125 patients with OCD and residual symptoms after cognitive behavioral therapy (CBT) were randomized to either an MBCT group (n = 61) or to a psychoeducational group (OCD-EP; n = 64) as an active control condition. At post-treatment, there was no significant benefit of MBCT over OCD-EP with the Yale-Brown-Obsessive-Compulsive Scale (Y-BOCS) as the primary outcome measure, but with the Obsessive-Compulsive Inventory [OCI-R; F(1, 101) = 5.679, p = .036, effect size η2partial = 0.053]. Moreover, the response rate and the improvement on secondary outcomes such as obsessive beliefs and quality of life was significantly larger in the MBCT group. Non-completion rates were below 10%. At the 6-month follow-up, OC symptoms were further improved in both groups; group differences were no longer significant. Our findings suggest that MBCT, compared to a psychoeducational program, leads to accelerated improvement of self-reported OC symptoms and secondary outcomes, but not of clinician-rated OC symptoms. In the midterm, both interventions yield similar and stable, but small improvements, suggesting that additional treatment options may be necessary.

In vitro evolution of high-titer, virus-like vesicles containing a single structural protein.

Self-propagating, infectious, virus-like vesicles (VLVs) are generated when an alphavirus RNA replicon expresses the vesicular stomatitis virus glycoprotein (VSV G) as the only structural protein. The mechanism that generates these VLVs lacking a capsid protein has remained a mystery for over 20 years. We present evidence that VLVs arise from membrane-enveloped RNA replication factories (spherules) containing VSV G protein that are largely trapped on the cell surface. After extensive passaging, VLVs evolve to grow to high titers through acquisition of multiple point mutations in their nonstructural replicase proteins. We reconstituted these mutations into a plasmid-based system from which high-titer VLVs can be recovered. One of these mutations generates a late domain motif (PTAP) that is critical for high-titer VLV production. We propose a model in which the VLVs have evolved in vitro to exploit a cellular budding pathway that is hijacked by many enveloped viruses, allowing them to bud efficiently from the cell surface. Our results suggest a basic mechanism of propagation that may have been used by primitive RNA viruses lacking capsid proteins. Capsids may have evolved later to allow more efficient packaging of RNA, greater virus stability, and evasion of innate immunity.

Virus-Like Vesicle-Based Therapeutic Vaccine Vectors for Chronic Hepatitis B Virus Infection.

UNLABELLED: More than 500,000 people die each year from the liver diseases that result from chronic hepatitis B virus (HBV) infection. Therapeutic vaccines, which aim to elicit an immune response capable of controlling the virus, offer a potential new treatment strategy for chronic hepatitis B. Recently, an evolved, high-titer vaccine platform consisting of Semliki Forest virus RNA replicons that express the vesicular stomatitis virus glycoprotein (VSV G) has been described. This platform generates virus-like vesicles (VLVs) that contain VSV G but no other viral structural proteins. We report here that the evolved VLV vector engineered to additionally express the HBV middle surface envelope glycoprotein (MHBs) induces functional CD8 T cell responses in mice. These responses were greater in magnitude and broader in specificity than those obtained with other immunization strategies, including recombinant protein and DNA. Additionally, a single immunization with VLV-MHBs protected mice from HBV hydrodynamic challenge, and this protection correlated with the elicitation of a CD8 T cell recall response. In contrast to MHBs, a VLV expressing HBV core protein (HBcAg) neither induced a CD8 T cell response in mice nor protected against challenge. Finally, combining DNA and VLV-MHBs immunization led to induction of HBV-specific CD8 T cell responses in a transgenic mouse model of chronic HBV infection. The ability of VLV-MHBs to induce a multispecific T cell response capable of controlling HBV replication, and to generate immune responses in a tolerogenic model of chronic infection, indicates that VLV vaccine platforms may offer a unique strategy for HBV therapeutic vaccination. IMPORTANCE: HBV infection is associated with significant morbidity and mortality. Furthermore, treatments for chronic infection are suboptimal and rarely result in complete elimination of the virus. Therapeutic vaccines represent a unique approach to HBV treatment and have the potential to induce long-term control of infection. Recently, a virus-based vector system that combines the nonstructural proteins of Semliki Forest virus with the VSV glycoprotein has been described. In this study, we used this system to construct a novel HBV vaccine and demonstrated that the vaccine is capable of inducing virus-specific immune responses in mouse models of acute and chronic HBV replication. These findings highlight the potential of this new vaccine system and support the idea that highly immunogenic vaccines, such as viral vectors, may be useful in the treatment of chronic hepatitis B.

Mindfulness-based cognitive therapy in obsessive-compulsive disorder: protocol of a randomized controlled trial.

BACKGROUND: Obsessive-compulsive disorder (OCD) is a very disabling condition with a chronic course, if left untreated. Though cognitive behavioral treatment (CBT) with or without selective serotonin reuptake inhibitors (SSRI) is the method of choice, up to one third of individuals with obsessive-compulsive disorder (OCD) do not respond to treatment in terms of at least 35% improvement of symptoms. Mindfulness based cognitive therapy (MBCT) is an 8-week group program that could help OCD patients with no or only partial response to CBT to reduce OC symptoms and develop a helpful attitude towards obsessions and compulsive urges. METHODS/DESIGN: This study is a prospective, bicentric, assessor-blinded, randomized, actively-controlled clinical trial. 128 patients with primary diagnosis of OCD according to DSM-IV and no or only partial response to CBT will be recruited from in- and outpatient services as well as online forums and the media. Patients will be randomized to either an MBCT intervention group or to a psycho-educative coaching group (OCD-EP) as an active control condition. All participants will undergo eight weekly sessions with a length of 120 minutes each of a structured group program. We hypothesize that MBCT will be superior to OCD-EP in reducing obsessive-compulsive symptoms as measured by the Yale-Brown-Obsessive-Compulsive Scale (Y-BOCS) following the intervention and at 6- and 12-months-follow-up. Secondary outcome measures include depressive symptoms, quality of life, metacognitive beliefs, self-compassion, mindful awareness and approach-avoidance tendencies as measured by an approach avoidance task. DISCUSSION: The results of this study will elucidate the benefits of MBCT for OCD patients who did not sufficiently benefit from CBT. To our knowledge, this is the first randomized controlled study assessing the effects of MBCT on symptom severity and associated parameters in OCD. TRIAL REGISTRATION: German Clinical Trials Register DRKS00004525 . Registered 19 March 2013.

[Mindfulness based cognitive therapy (MBCT) in patients with obsessive-compulsive disorder--an adaptation of the original program]. / Achtsamkeitsbasierte kognitive Therapie (MBCT) für Patienten mit Zwangsstörung--Eine Adaptation des Originalkonzepts.

Mindfulness-based cognitive Therapy (MBCT) has shown to be effective in the relapse prevention and treatment of several psychiatric disorders. However, MBCT has not yet been applied in OCD (Obsessive-compulsive Disorder). This article proposes an adaptation of the eight-session group program for patients with residual symptoms after cognitive behavioural treatment (CBT) with exposure. It has proven feasible and was considered helpful by patients within the framework of a pilot study 1. Apart from an overview of the modified manual, OCD-specific elements are presented in detail and illustrated on the base of work sheets. The manual indicates that MBCT could be a useful supplement to CBT and is well applicable to the therapeutic needs of patients with OCD.

A risk for hepatocellular carcinoma persists long-term after sustained virologic response in patients with hepatitis C-associated liver cirrhosis.

BACKGROUND: The long-term effect of sustained virologic response (SVR) to antiviral therapy on the risk of developing hepatocellular carcinoma (HCC), liver complications, liver-related death, and overall death in hepatitis C virus (HCV)-infected patients with liver cirrhosis is not fully known. METHODS: These risks were evaluated during long-term follow-up in 351 patients with HCV-related cirrhosis. One hundred ten patients with SVR, 193 with non-SVR, and 48 who were untreated were included in a multicenter cohort that was initiated in 2001 and prospectively followed up for a mean of 5.3 (SD, 2.8) years. Complementary follow-up data from national registries were used to minimize the loss of patients during follow-up. RESULTS: Six patients with SVR developed HCC at 0.04, 0.64, 2.4, 7.4, 7.4, and 7.6 years, respectively, after achieving SVR. The incidences of HCC, any liver complication, liver-related death, and overall death per 100 person-years were significantly lower in SVR time with 1.0, 0.9, 0.7, and 1.9, compared to 2.3, 3.2, 3.0, and 4.1 in non-SVR and 4.0, 4.9, 4.5, and 5.1 in untreated time. The long-term consequences did not decline significantly after >3 years versus during the first 3 years of follow-up. CONCLUSIONS: The risk for HCC, liver decompensation, and death in patients with liver cirrhosis related to HCV was markedly reduced after SVR, but a long-term risk of developing HCC remains for up to 8 years. Cirrhotic patients with HCV who achieve SVR should therefore maintain long-term surveillance for HCC. Future studies aimed to better identify those with remaining long-term risk for HCC are needed.

Significant protection against high-dose simian immunodeficiency virus challenge conferred by a new prime-boost vaccine regimen.

We constructed vaccine vectors based on live recombinant vesicular stomatitis virus (VSV) and a Semliki Forest virus (SFV) replicon (SFVG) that propagates through expression of the VSV glycoprotein (G). These vectors expressing simian immunodeficiency virus (SIV) Gag and Env proteins were used to vaccinate rhesus macaques with a new heterologous prime-boost regimen designed to optimize induction of antibody. Six vaccinated animals and six controls were then given a high-dose mucosal challenge with the diverse SIVsmE660 quasispecies. All control animals became infected and had peak viral RNA loads of 10(6) to 10(8) copies/ml. In contrast, four of the vaccinees showed significant (P = 0.03) apparent sterilizing immunity and no detectable viral loads. Subsequent CD8(+) T cell depletion confirmed the absence of SIV infection in these animals. The two other vaccinees had peak viral loads of 7 × 10(5) and 8 × 10(3) copies/ml, levels below those of all of the controls, and showed undetectable virus loads by day 42 postchallenge. The vaccine regimen induced high-titer prechallenge serum neutralizing antibodies (nAbs) to some cloned SIVsmE660 Env proteins, but antibodies able to neutralize the challenge virus swarm were not detected. The cellular immune responses induced by the vaccine were generally weak and did not correlate with protection. Although the immune correlates of protection are not yet clear, the heterologous VSV/SFVG prime-boost is clearly a potent vaccine regimen for inducing virus nAbs and protection against a heterogeneous viral swarm.

Mindfulness-based cognitive therapy in obsessive-compulsive disorder - a qualitative study on patients' experiences.

BACKGROUND: Cognitive behavioral therapy (CBT) with exposure and response prevention (ERP) is the first-line treatment for patients with obsessive-compulsive disorder (OCD). However, not all of them achieve remission on a longterm basis. Mindfulness-based cognitive therapy (MBCT) represents a new 8-week group therapy program whose effectiveness has been demonstrated in various mental disorders, but has not yet been applied to patients with OCD. The present pilot study aimed to qualitatively assess the subjective experiences of patients with OCD who participated in MBCT. METHOD: Semi-structured interviews were conducted with 12 patients suffering from OCD directly after 8 sessions of a weekly MBCT group program. Data were analyzed using a qualitative content analysis. RESULTS: Participants valued the treatment as helpful in dealing with their OCD and OCD-related problems. Two thirds of the patients reported a decline in OCD symptoms. Benefits included an increased ability to let unpleasant emotions surface and to live more consciously in the present. However, participants also discussed several problems. CONCLUSION: The data provide preliminary evidence that patients with OCD find aspects of the current MBCT protocol acceptable and beneficial. The authors suggest to further explore MBCT as a complementary treatment strategy for OCD.

Hybrid alphavirus-rhabdovirus propagating replicon particles are versatile and potent vaccine vectors.

Self-propagating, infectious, virus-like particles are generated in animal cell lines transfected with a Semliki Forest virus RNA replicon encoding a single viral structural protein, the vesicular stomatitis virus (VSV) glycoprotein. We show here that these infectious particles, which we call propagating replicons, are potent inducers of neutralizing antibody in animals yet are nonpathogenic. Mice vaccinated with a single dose of the particles generated high titers of VSV-neutralizing antibody and were protected from a subsequent lethal challenge with VSV. Induction of antibody required RNA replication. We also report that additional genes (including an HIV-1 envelope protein gene) expressed from the propagating replicons induced strong cellular immune responses to the corresponding proteins after a single inoculation. Our studies reveal the potential of these particles as simple and safe vaccine vectors inducing strong humoral and cellular immune responses.

Alexithymia, Affective Lability, Impulsivity, and Childhood Adversity in Borderline Personality Disorder.

Long-standing theories of borderline personality disorder (BPD) suggest that symptoms develop at least in part from childhood adversity. Emotion dysregulation may meaningfully mediate these effects. The current study examined three factors related to emotion dysregulation-alexithymia, affective lability, and impulsivity-as potential mediators of the relation between childhood adversity and BPD diagnosis in 101 individuals with BPD and 95 healthy controls. Path analysis compared three distinct models informed by the literature. Results supported a complex mediation model wherein (a) alexithymia partially mediated the relation of childhood adversity to affective lability and impulsivity; (b) affective lability mediated the relation of childhood adversity to BPD diagnosis; and (c) affective lability and impulsivity mediated the relation of alexithymia to BPD diagnosis. Findings suggest that affective lability and alexithymia are key to understanding the relationship between childhood adversity and BPD. Interventions specifically targeting affective lability, impulsivity, and alexithymia may be particularly useful for this population.

Long-term effects of mindfulness-based cognitive therapy in patients with obsessive-compulsive disorder and residual symptoms after cognitive behavioral therapy: Twelve-month follow-up of a randomized controlled trial.

We examined the long-term efficacy of mindfulness-based cognitive therapy (MBCT) compared to a psychoeducation group as an active control condition in patients with obsessive-compulsive disorder (OCD) with residual symptoms of OCD after cognitive behavioral therapy. A total of 125 patients were included in a bicentric, interviewer-blind, randomized, and actively controlled trial and were assigned to either an MBCT group (n = 61) or a psychoeducation group (n = 64). Patients' demographic characteristics and the results from our previous assessments have already been reported (Külz et al., 2019). At the 12-month follow-up the completion rate was 80%. OCD symptoms were reduced from baseline to follow-up assessment with a large effect, but no difference was found between groups. Exploratory analyses showed that a composite score of time occupied by obsessive thoughts, distress associated with obsessive thoughts, and interference due to obsessive thoughts differed between groups in the per-protocol analysis, with a stronger reduction in the MBCT group. At the 12-month follow-up, the two groups showed a similar reduction of symptoms. However, preliminary evidence indicates that MBCT has a superior effect on some aspects of OCD. This should be replicated in future studies.

Priming with plasmid DNAs expressing interleukin-12 and simian immunodeficiency virus gag enhances the immunogenicity and efficacy of an experimental AIDS vaccine based on recombinant vesicular stomatitis virus.

Of the various approaches being developed as prophylactic HIV vaccines, those based on a heterologous plasmid DNA prime, live vector boost vaccination regimen appear especially promising in the nonhuman primate/simian-human immunodeficiency virus (SHIV) challenge model. In this study, we sought to determine whether a series of intramuscular priming immunizations with a plasmid DNA vaccine expressing SIVgag p39, in combination with plasmid expressed rhesus IL-12, could effectively enhance the immunogenicity and postchallenge efficacy of two intranasal doses of recombinant vesicular stomatitis virus (rVSV)-based vectors expressing HIV-1 env 89.6P gp160 and SIVmac239 gag p55 in rhesus macaques. In macaques receiving the combination plasmid DNA prime, rVSV boost vaccination regimen we observed significantly increased SIVgag- specific cell-mediated and humoral immune responses and significantly lower viral loads postintravenous SHIV89.6P challenge relative to macaques receiving only the rVSV vectored immunizations. In addition, the plasmid DNA prime, rVSV boost vaccination regimen also tended to increase the preservation of peripheral blood CD4+ cells and reduce the morbidity and mortality associated with SHIV89.6P infection. An analysis of immune correlates of protection after SHIV89.6P challenge revealed that the prechallenge SHIV-specific IFN-gamma ELISpot response elicited by vaccination and the ability of the host to mount a virus-specific neutralizing antibody response postchallenge correlated with postchallenge clinical outcome. The correlation between vaccine-elicited cell-mediated immune responses and an improved clinical outcome after SHIV challenge provides strong justification for the continued development of a cytokine-enhanced plasmid DNA prime, rVSV vector boost immunization regimen for the prevention of HIV infection.

Antigenic requirement for Gag in a vaccine that protects against high-dose mucosal challenge with simian immunodeficiency virus.

We reported previously on a vaccine approach that conferred apparent sterilizing immunity to SIVsmE660. The vaccine regimen employed a prime-boost using vectors based on recombinant vesicular stomatitis virus (VSV) and an alphavirus replicon expressing either SIV Gag or SIV Env. In the current study, we tested the ability of vectors expressing only the SIVsmE660 Env protein to protect macaques against the same high-dose mucosal challenge. Animals developed neutralizing antibody levels comparable to or greater than seen in the previous vaccine study. When the vaccinated animals were challenged with the same high-dose of SIVsmE660, all became infected. While average peak viral loads in animals were slightly lower than those of previous controls, the viral set points were not significantly different. These data indicate that Gag, or the combination of Gag and Env are required for the generation of apparent sterilizing immunity to the SIVsmE660 challenge.

Immunogenicity of attenuated vesicular stomatitis virus vectors expressing HIV type 1 Env and SIV Gag proteins: comparison of intranasal and intramuscular vaccination routes.

An experimental AIDS vaccine based on attenuated, recombinant vesicular stomatitis virus (rVSV), when administered by a combination of parenteral and mucosal routes, has proven effective at preventing AIDS in a rhesus macaque model (Rose NF, et al.: Cell 2001;106:539-549). In an effort to determine the optimal route of vaccine administration we evaluated the ability of rVSV-based vaccine vectors expressing HIV-1 Env and SIV Gag proteins, when given either intramuscularly (i.m.) or intranasally (i.n.), to elicit antigen-specific cellular and humoral immune responses, and to protect from a subsequent vaginal challenge with simian-human immunodeficiency virus (SHIV89.6P). Our results demonstrate that macaques vaccinated by the i.n. route developed significantly higher antigen-specific cellular immune responses as determined by MHC class I tetramer staining, IFN-gamma ELISPOT, and cytotoxic T cell assays. However, systemic and mucosal humoral immune responses did not vary significantly with the route of vaccine administration. Given the importance of cell-mediated immune responses in slowing AIDS progression, intranasal delivery of a VSV-based AIDS vaccine may be an optimal as well as practical route for vaccination and should be considered in design of clinical trials.

Transmitted/founder simian immunodeficiency virus envelope sequences in vesicular stomatitis and Semliki forest virus vector immunized rhesus macaques.

Identification of transmitted/founder simian immunodeficiency virus (SIV) envelope sequences responsible for infection may prove critical for understanding HIV/SIV mucosal transmission. We used single genome amplification and phylogenetic analyses to characterize transmitted/founder SIVs both in the inoculum and in immunized-infected rhesus monkeys. Single genome amplification of the SIVsmE660 inoculum revealed a maximum diversity of 1.4%. We also noted that the consensus sequence of the challenge stock differed from the vaccine construct in 10 amino acids including 3 changes in the V4 loop. Viral env was prepared from rhesus plasma in 3 groups of 6 immunized with vesicular stomatitis virus (VSV) vectors and boosted with Semliki forest virus (SFV) replicons expressing (a) SIVsmE660 gag-env (b) SIVsmE660 gag-env plus rhesus GM-CSF and (c) control influenza hemagglutinin protein. Macaques were immunized twice with VSV-vectors and once with SFV vector and challenged intrarectally with 4000 TCID50. Single genome amplification characterized the infections of 2 unprotected animals in the gag-env immunized group, both of which had reduced acute plasma viral loads that ended as transient infections indicating partial immune control. Four of 6 rhesus were infected in the gag-env + GM-CSF group which demonstrated that GM-CSF abrogated protection. All 6 animals from the control group were infected having high plasma viral loads. We obtained 246 full-length envelope sequences from SIVsmE660 infected macaques at the peak of infection and determined the number of transmitted/founder variants per animal. Our analysis found that 2 of 2 gag-env vaccinated but infected macaques exhibited single but distinct virus envelope lineages whereas rhesus vaccinated with gag-env-GM-CSF or HA control exhibited both single and multiple env lineages. Because there were only 2 infected animals in the gag-env vaccinated rhesus compared to 10 infected rhesus in the other 2 groups, the significance of finding single env variants in the gag-env vaccinated group could not be established.

Viral vectored granulocyte-macrophage colony stimulating factor inhibits vaccine protection in an SIV challenge model: protection correlates with neutralizing antibody.

In a previous vaccine study, we reported significant and apparently sterilizing immunity to high-dose, mucosal, simian immunodeficiency virus (SIV) quasi-species challenge. The vaccine consisted of vectors based on vesicular stomatitis virus (VSV) expressing simian immunodeficiency virus (SIV) gag and env genes, a boost with propagating replicon particles expressing the same SIV genes, and a second boost with VSV-based vectors. Concurrent with that published study we had a parallel group of macaques given the same doses of vaccine vectors, but in addition, we included a third VSV vector expressing rhesus macaque GM-CSF in the priming immunization only. We report here that addition of the vector expressing GM-CSF did not enhance CD8 T cell or antibody responses to SIV antigens, and almost completely abolished the vaccine protection against high-dose mucosal challenge with SIV. Expression of GM-CSF may have limited vector replication excessively in the macaque model. Our results suggest caution in the use of GM-CSF as a vaccine adjuvant, especially when expressed by a viral vector. Combining vaccine group animals from this study and the previous study we found that there was a marginal but significant positive correlation between the neutralizing antibody to a neutralization resistant SIV Env and protection from infection.

Partial efficacy of a VSV-SIV/MVA-SIV vaccine regimen against oral SIV challenge in infant macaques.

Despite antiretroviral medications, the rate of pediatric HIV-1 infections through breast-milk transmission has been staggering in developing countries. Therefore, the development of a vaccine to protect vulnerable infant populations should be actively pursued. We previously demonstrated that oral immunization of newborn macaques with vesicular stomatitis virus expressing simian immunodeficiency virus genes (VSV-SIV) followed 2 weeks later by an intramuscular boost with modified vaccinia ankara virus expressing SIV (MVA-SIV) successfully induced SIV-specific T and B cell responses in multiple lymphoid tissues, including the tonsil and intestine [13]. In the current study, we tested the oral VSV-SIV prime/systemic MVA-SIV boost vaccine for efficacy against multiple oral SIVmac251 challenges starting two weeks after the booster vaccination. The vaccine did not prevent SIV infection. However, in vaccinated infants, the level of SIV-specific plasma IgA (but not IgG) at the time of challenge was inversely correlated with peak viremia. In addition, the levels of SIV-specific IgA in saliva and plasma were inversely correlated with viral load at euthanasia. Animals with tonsils that contained higher frequencies of SIV-specific TNF-α- or IFN-γ-producing CD8(+) T cells and central memory T cells at euthanasia also had lower viremia. Interestingly, a marked depletion of CD25(+)FoxP3(+)CD4(+) T cells was observed in the tonsils as well as the intestine of these animals, implying that T regulatory cells may be a major target of SIV infection in infant macaques. Overall, the data suggest that, in infant macaques orally infected with SIV, the co-induction of local antiviral cytotoxic T cells and T regulatory cells that promote the development of IgA responses may result in better control of viral replication. Thus, future vaccination efforts should be directed towards induction of IgA and mucosal T cell responses to prevent or reduce virus replication in infants.

Immunogenicity of viral vector, prime-boost SIV vaccine regimens in infant rhesus macaques: attenuated vesicular stomatitis virus (VSV) and modified vaccinia Ankara (MVA) recombinant SIV vaccines compared to live-attenuated SIV.

In a previously developed infant macaque model mimicking HIV infection by breast-feeding, we demonstrated that intramuscular immunization with recombinant poxvirus vaccines expressing simian immunodeficiency virus (SIV) structural proteins provided partial protection against infection following oral inoculation with virulent SIV. In an attempt to further increase systemic but also local antiviral immune responses at the site of viral entry, we tested the immunogenicity of different orally administered, replicating vaccines. One group of newborn macaques received an oral prime immunization with a recombinant vesicular stomatitis virus expressing SIVmac239 gag, pol and env (VSV-SIVgpe), followed 2 weeks later by an intramuscular boost immunization with MVA-SIV. Another group received two immunizations with live-attenuated SIVmac1A11, administered each time both orally and intravenously. Control animals received mock immunizations or non-SIV VSV and MVA control vectors. Analysis of SIV-specific immune responses in blood and lymphoid tissues at 4 weeks of age demonstrated that both vaccine regimens induced systemic antibody responses and both systemic and local cell-mediated immune responses. The safety and immunogenicity of the VSV-SIVgpe+MVA-SIV immunization regimen described in this report provide the scientific incentive to explore the efficacy of this vaccine regimen against virulent SIV exposure in the infant macaque model.