Efficacity and Safety of the Fluocinolone Acetonide Implant in Uveitic Macular Edema: A Real-Life Study from the French Uveitis Network.

PURPOSE: To evaluate the safety and efficacy of the fluocinolone acetonide implant (FAi, Iluvien® Horus pharma, Nice, France) in non-infectious uveitic macular edema (UME) and to approach the predictive factors of treatment response. METHODS: This retrospective, multicenter real-life study included patients with chronic non-infectious UME who received intravitreal FAi after at least two dexamethasone implants (DEXi). RESULTS: Twenty-six eyes from 22 patients (73.1% of females) were included. The mean age was 60.4 ± 16 years. The mean follow-up was 11.4 ± 2 months. The mean baseline best-corrected visual acuity (BCVA) was 0.43 ± 0.36 LogMAR, improving significantly after 1, 3, 6 and 12 months (all p < 0.05 vs. baseline). The mean baseline central macular thickness (CMT) was 429 ± 110 µm, improving significantly after 1, 3, 6 and 12 months (all p < 0.05 vs. baseline). Five eyes (19.2%) developed ocular hypertension during the follow-up, requiring initiation or strengthening of intraocular pressure lowering medication. The majority of eyes (77%) did not require any rescue DEXi during the available 12-month follow-up. The resolution of UME after DEXi seemed to predict the anatomical response after FAi. The baseline presence of a disorganization of the inner retinal layers (DRIL) and hyperreflective foci (HRF) were both associated with a higher likelihood of requiring rescue DEXi injections. CONCLUSION: FAi implantation led to a significant BCVA and CMT improvement with a good safety profile over the 12-month follow-up. Predictive factors of treatment outcomes seem to include the anatomical response to DEXi and the presence of DRIL and HRF at baseline.

Fluocinolone Acetonide Implant Injected 1 Month after Dexamethasone Implant for Diabetic Macular Oedema: the ILUVI1MOIS Study.

INTRODUCTION: The aim of this study was to assess the efficacy and safety of fluocinolone acetonide implant (FAci) injected 1 month after the last dexamethasone intravitreal implant (DEXi) in chronic diabetic macular oedema (DME) patients. METHODS: Retrospective multicentric study conducted in pseudophakic patients with chronic DME frequently treated with dexamethasone intravitreal implant (DEXi; time to DME recurrence ≤ 6 months), receiving FAci 1 month after the last DEXi, with at least a 6-month follow-up. Best-corrected visual acuity (BCVA), central macular thickness (CMT) on optical coherence tomography, intraocular pressure (IOP) and additional treatments were assessed on the day of FAci injection (M0), 1 (M1) and 3 months (M3) later and then every 3 months. RESULTS: A total of 41 eyes from 34 patients were included. At M0, patients' mean age was 68.7 ± 9.8 years, the mean DME duration was 63.9 ± 22.9 months, the mean interval between two DEXi was 14.2 ± 3.3 weeks. M12 data were available for 71% of patients. At baseline, the mean BCVA, CMT and IOP were 63.2 ± 16.6 letters, 299.4 ± 103.3 µm, and 16.2 ± 4.5 mmHg, respectively, and remained stable during the follow-up. At M12, 14% of patients required additional intravitreal treatments. CONCLUSION: In pseudophakic patients with chronic DME showing good response to DEXi but requiring repeated injections every < 6 months, switching to FAci 1 month after the last DEXi was effective and safe. Further prospective randomized controlled studies are needed to confirm these findings, and to determine the best interval between the last DEXi and the first FAci.

Intravenous high-dose methotrexate based systemic therapy in the treatment of isolated primary vitreoretinal lymphoma: An LOC network study.

The treatment of primary vitreoretinal lymphoma (PVRL) remains controversial regarding the use of local, systemic, or combined treatments. The aim of this study was to analyze the efficacy and toxicity of intravenous high-dose methotrexate (IV HD-MTX) based systemic therapy in a uniformly treated population of PVRL patients. From a nationwide French database, we retrospectively selected 59 patients (median age: 70 years, median Karnofsky Performance Status: 90%) with isolated PVRL at diagnosis who received first-line treatment with HD-MTX between 2011 and 2018. 8/59 patients also received a local treatment. No deaths or premature discontinuations of MTX due to toxicity were reported. A complete response was obtained in 40/57 patients after chemotherapy. Before treatment, IL-10 was elevated in the aqueous humor (AH) or in the vitreous in 89% of patients. After treatment, AH IL-10 was undetectable in 87% of patients with a CR/uCR/PR and detectable in 92% of patients with PD/SD. After a median follow-up of 61 months, 42/59 (71%) patients had relapsed, including 29 isolated ocular relapses as the first relapse and a total of 22 brain relapses. The median overall survival, progression-free survival, ocular-free survival and brain-free survival were 75, 18, 29 and 73 months, respectively. IV HD-MTX based systemic therapy as a first-line treatment for isolated PVRL is feasible, with acceptable toxicity, even in an elderly population. This strategy seems efficient to prevent brain relapse with prolonged overall survival. However, the ocular relapse rate remains high. New approaches are needed to improve local control of this disease, and ocular assessment could be completed by monitoring AH IL-10.

Tele-ophthalmology for screening for eye diseases in older patients with cognitive complaints.

INTRODUCTION: Population-based studies show a significant increase in the prevalence of visual impairment in older patients. However, older patients and patients with lower Mini-Mental State Examination (MMSE) scores have few ophthalmological assessments. The main objective of our study was to evaluate the feasibility of tele-ophthalmological screening for ophthalmological diseases in older patients referred for cognitive assessment. METHODS: This monocentric prospective study included patients referred to a memory clinic for cognitive assessment. All patients underwent a geriatric assessment comprising a cognitive assessment associated with tele-ophthalmological screening undertaken by an orthoptist, including undilated retinal photography. The retinal photographs were subsequently sent to an ophthalmologist. We identified patients who were not eligible for ophthalmological assessment, for patients that had to come back due to poor-quality retinal photographs and finally for detected eye diseases. The association between the geriatric variable and newly detected eye diseases was analysed in univariable and multivariable analyses. RESULTS: The mean age of the 298 patients included was 83.5 years ± 5.65; 29.5% were male. The mean MMSE score was 20.8 ± 5.2; 66.3% of patients had a diagnosis of dementia. Eighteen patients (6.0%) were not eligible for ophthalmological examination and 13 patients (4.6%) were asked to come back owing to poor-quality retinal photographs. Forty-one patients (13.7%) had a newly detected eye disease. In multivariable analysis, patients with a lower MMSE had significantly more newly identified eye diseases. DISCUSSION: The tele-ophthalmological screening method identified unknown ophthalmological diseases requiring specialised management in this older population with cognitive complaints.

Morphological Predictive Features on Spectral-Domain Optical Coherence Tomography for Visual Outcomes in Neovascular Age-Related Macular Degeneration Treated with Ranibizumab.

PURPOSE: To identify spectral-domain optical coherence tomography (SD-OCT) predictive morphological features for the outcome of Ranibizumab therapy for neovascular age-related macular degeneration (AMD). METHODS: This is a retrospective multicentric study that involved 64 eyes with naïve AMD. Patients who received three monthly intravitreal injections of Ranibizumab were stratified into (1) "responders" [≥ 5 letters gain on Early Treatment Diabetic Retinopathy Study (ETDRS) scale] and (2) "nonresponders" (< 5 letters gain). Best-corrected visual acuity (BCVA) and SD-OCT morphological features were compared at baseline and one month after three consecutive injections of Ranibizumab. Univariate and multivariate analyses were carried out to correlate these morphological features with the change in BCVA. RESULTS: Among the 64 patients enrolled, 40 (62.5%) were "responders" and 24 (37.5%) "nonresponders". Age, sex, and BCVA were comparable between both groups. A multivariate correlational analysis found that subfoveal choroidal thickness (SFCT) and the presence of pigment epithelial detachment (PED) > 250 µm at baseline were two independent prognostic indicators of final BCVA. No other SD-OCT morphological studied features seem to affect final BCVA after Ranibizumab treatment. CONCLUSION: SFCT and the presence of PED > 250 µm are two significant biomarkers that may predict improvement after Ranibizumab therapy for AMD. These markers may guide ophthalmologists' treatment decision under financial constraints and limited time.

DETRIMENTAL EFFECTS OF ACTIVE INTERNAL LIMITING MEMBRANE PEELING DURING EPIRETINAL MEMBRANE SURGERY: Microperimetric Analysis.

INTRODUCTION: The aim of the study was to assess the microperimetric consequences of active internal limiting membrane (ILM) peeling during idiopathic epimacular membrane (IEMM) surgery. MATERIALS AND METHODS: This retrospective monocentric study included 32 eyes of 31 consecutive patients who underwent IEMM surgery. Internal limiting membrane integrity was assessed by ILM Blue staining after IEMM removal: peeling was spontaneous (Group S) or active (Group A). Preprocedure and postprocedure (1 and 6 months) examinations were performed using visual acuity determination, spectral domain optical coherence tomography and microperimetry. RESULTS: Twenty-two eyes had an "active ILM peeling" and 10 a "spontaneous ILM peeling." Both groups had comparable and significant improvements in visual acuity 6 months after surgery (+1.82 lines [+9 letters] [Group A] and +1.51 lines [+8 letters] [Group S], P < 0.01) associated with a significant reduction in optical coherence tomography central thickness (-99.9 µm [Group A], P < 0.01 and -62.2 µm [Group S], P = 0.05). Six months after surgery, the microperimetry showed more numerous and deeper microscotomas in the Group A than in the Group S (change in the number of microscotomas: 2.09 vs. -0.10, P = 0.06; change in deficit severity score: 13.18 dB vs. -2 dB, P < 0.01 for Group A and S, respectively). The number of microscotomas and also severity were increased in 63.6% of Group A patients and in only 20% of Group S patients. Microscotomas were most frequently located in IEMM and/or ILM areas. DISCUSSION: Internal limiting membrane peeling has progressively become generalized in IEMM surgery to reduce recurrences. This additional procedure does not change the postoperative visual acuity but increases the development of deeper microscotomas. The real impact on the quality of vision remains unclear. CONCLUSION: Active ILM peeling in IEMM surgery may be responsible for visual impairment related to its microtraumatic effects.

Structure-activity relationships of imidazole-derived 2-[N-carbamoylmethyl-alkylamino]acetic acids, dual binders of human insulin-degrading enzyme.

Insulin degrading enzyme (IDE) is a zinc metalloprotease that degrades small amyloid peptides such as amyloid-â and insulin. So far the dearth of IDE-specific pharmacological inhibitors impacts the understanding of its role in the physiopathology of Alzheimer's disease, amyloid-â clearance, and its validation as a potential therapeutic target. Hit 1 was previously discovered by high-throughput screening. Here we describe the structure-activity study, that required the synthesis of 48 analogues. We found that while the carboxylic acid, the imidazole and the tertiary amine were critical for activity, the methyl ester was successfully optimized to an amide or a 1,2,4-oxadiazole. Along with improving their activity, compounds were optimized for solubility, lipophilicity and stability in plasma and microsomes. The docking or co-crystallization of some compounds at the exosite or the catalytic site of IDE provided the structural basis for IDE inhibition. The pharmacokinetic properties of best compounds 44 and 46 were measured in vivo. As a result, 44 (BDM43079) and its methyl ester precursor 48 (BDM43124) are useful chemical probes for the exploration of IDE's role.

Inhibition of aggrecanases as a therapeutic strategy in osteoarthritis.

Over the last decade, there has been a large effort to target aggrecanases, which are responsible for the degradation of the aggrecan in the extracellular matrix of joints, in order to hopefully lead to new treatments for osteoarthritis. Only a few inhibitors have been effective in explants or rodent models and thus only a few have reached the clinic, none of which have proven to be effective. In this article, a survey of chemical series is described, covering historical and recent inhibitors and highlighting how some of their problems were resolved, with a critical overview of the challenges encountered. A large effort should be undertaken in designing smaller compounds with higher residence times, defining new interaction sites on the aggrecanases and exploiting target flexibility.

Mitoxantrone therapy for acute posterior multifocal placoid pigment epitheliopathy with cerebral vasculitis.

Purpose. To report favorable outcome of a case of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) associated with cerebral vasculitis after treatment with immunosuppressive therapy by mitoxantrone. Design. Single case report. Method. A 22-year-old man presented with acute isolated bilateral loss of vision revealing APMPPE. Corticosteroid therapy was initiated and visual acuity gradually improved. Seventeen days later, visual function deteriorated again, associated with flu-like syndrome and severe headaches. A relapse of APMPPE was diagnosed, complicated with lymphocytic meningitis and cerebral ischemia. Intravenous therapy with mitoxantrone was performed in combination with methylprednisolone. Results. Headaches disappeared in a few days whereas visual acuity gradually improved and stabilized at 20/40 in the right eye and 20/32 in the left eye. No adverse event was observed. Clinical improvement was confirmed by magnetic resonance imaging. Conclusion. Cerebral vasculitis is the most severe complication of the extraocular manifestations of APMPEE. This diagnosis should be evoked when severe headaches or behavior disorder are associated with APMPEE.

Parallel synthesis of a lipopeptide library by hydrazone-based chemical ligation.

alpha-Melanocyte-stimulating hormone (alpha-MSH) is an endogeneous linear tridecapeptide with potential application for the modulation of skin tanning. To evaluate the interest of introducing a lipid moiety onto this peptide, we developed an efficient chemoselective parallel method to prepare a large series of analogues of alpha-melanocortin with high purity, varying the nature or the relative position of the lipid moiety. Two sets of building blocks containing lipidic alpha-oxo-aldehydes or alpha-hydrazinoacetyl peptides were combined to obtain a 102-membered library of amphiphilic alpha-MSH analogues. This library was pharmacologically tested at 1 x 10(-7) M for the ability to induce AMPc production in M4Be melanoma cell line after stimulation of the human melanocortin MC1 receptor. Among theses lipopeptides, 84 compounds exhibited an AMPc induction higher than Melitane, a patented alpha-MSH agonist. These results provide strong evidence of the interest of introduction of a lipid tail for the pharmacomodulation of bioactive peptides.

SIV escape mutants in rhesus macaques vaccinated with NEF-derived lipopeptides and challenged with pathogenic SIVmac251.

BACKGROUND: Emergence of viral variants that escape CTL control is a major hurdle in HIV vaccination unless such variants affect gene regions that are essential for virus replication. Vaccine-induced multispecific CTL could also be able to control viral variants replication. To explore these possibilities, we extensively characterized CTL responses following vaccination with an epitope-based lipopeptide vaccine and challenge with pathogenic SIVmac251. The viral sequences corresponding to the epitopes present in the vaccine as well as the viral loads were then determined in every macaque following SIV inoculation. RESULTS: In most cases, the emergence of several viral variants or mutants within vaccine CTL epitopes after SIV challenge resulted in increased viral loads except for a single macaque, which showed a single escape viral variant within its 6 vaccine-induced CTL epitopes. CONCLUSION: These findings provide a better understanding of the evolution of CD8+ epitope variations after vaccination-induced CTL expansion and might provide new insight for the development of an effective HIV vaccine.

Effect of glycoamphiphiles on the solubilization and dendritic cell uptake of a lipopeptide: a preliminary study.

The selective delivery of antigens to professional antigen-presenting cells represents a promising approach to improve vaccine efficacy. Addition of a glycoamphiphile to a lipopeptide, whose interest for vaccination is now well-established, greatly favors its solubilization in aqueous solutions through the formation of mixed vesicles. Flow cytometry experiments indicate that this formulation does not diminish the uptake of the lipopeptide by the dendritic cells (DCs). These preliminary results suggest a possible straightforward, noncovalent targeting of cocktail-lipopeptide vaccines to the DCs via carbohydrate receptor-mediated endocytosis.

Anchorage of synthetic peptides onto liposomes via hydrazone and alpha-oxo hydrazone bonds. preliminary functional investigations.

Synthetic peptidoliposomes have been designed and prepared according to a chemoselective ligation. Two aldehyde-functionalized lipidic anchors were synthesized and incorporated into the lipidic bilayers of unilamellar liposomes during their preparation. Complementary hydrazino acetyl peptides were synthesized on the solid phase using N,N',N'-tri(tert-butyloxycarbonyl)-hydrazino acetic acid and further coupled to the aldehyde groups displayed at the surface of the vesicles. Coupling yields were measured by amino acid hydrolysis following total acid hydrolysis. The ligation methodology proved superior to the simple insertion of lipopeptides, which was performed for comparison in terms of yields, implementation, and reproducibility. To check whether the grafted-peptides were accessible and functional, cytoplasmic sequences of LAMP protein (lysosomal associated membrane protein), which is involved in intracellular membrane trafficking, have been selected. Using this model, we demonstrated in vitro the specific interaction of the synthetic LAMP-peptidoliposomes with the cytoplasmic adaptor protein AP-3, a result that contributes to the understanding of protein sorting in cells. Thus, these results clearly indicate the usefulness of such peptidoliposomes, easily prepared by hydrazone chemoselective ligation, as a tool for biological investigation.

Evaluation of SIV-lipopeptide immunizations administered by the intradermal route in their ability to induce antigen specific T-cell responses in rhesus macaques.

Numerous clinical and experimental observations have shown that cellular immunity, in particular CD8+ T-lymphocytes, plays an important role in the control of HIV infection. We have focused on a lipopeptide vaccination strategy that has been shown to induce polyepitopic T-cell responses in both animals and humans, in order to deliver simian immunodeficiency virus (SIV) antigens to rhesus macaques. Given the relevance of antigen administration route in the development of an effective cellular immune response, this study was designed to assess SIV lipopeptide immunizations administered either by the intradermal (ID) or the intramuscular (IM) routes in their ability to elicit GAG and NEF multispecific T-lymphocytes in the rhesus macaque. Antigen specific T-cell responses were observed between 7 and 11 weeks following vaccination in both groups. Macaques immunized by the IM route yielded antigen-specific IFN-gamma secreting lymphocytes in response to no more than two pools of peptides derived from SIV-NEF. In contrast, among the four ID-immunized macaques, two presented multi-specific T-cell responses to as many as four pools of SIV-NEF and/or GAG peptides. Responses persisted 16 weeks following the vaccination protocol in one of the ID-vaccinated macaques. The induction of such responses is of great clinical relevance in the development of an effective HIV vaccine. Given the crucial role of CD8+ T-lymphocytes in HIV/SIV containment, vaccination through the intradermal route should merit high consideration in the development of an AIDS vaccine.

Lipopeptide epitopes extended by an Nepsilon-palmitoyl-lysine moiety increase uptake and maturation of dendritic cells through a Toll-like receptor-2 pathway and trigger a Th1-dependent protective immunity.

Lipopeptides, a form of peptide immunogens, are currently under intense investigation as human vaccines for many infectious pathogens and cancers. However, the cellular and molecular mechanisms of lipopeptide immunogenicity are only partially understood. We have investigated the influence of the lipid content on the immunogenicity of lipopeptides using the herpes simplex virus type 1 (HSV-1) gD(1-23) peptide as a model antigen. Totally synthetic lipopeptides were constructed by covalent attachment to the peptide backbone of either Nepsilon-palmitoyl-lysine (palmitoyl-lipidated peptide, palmitoyl-LP) or cholesterol-lysine (cholesterol-lipidated peptide, cholesterol-LP). Immunization of mice with the palmitoyl-LP, but not with its cholesterol-LP analog, induced a strong T cell-dependent protective immunity against lethal HSV-1 infection. Analysis of cytokine profiles and IgG2a/IgG1 ratios revealed that a dominant Th1-type immune response was stimulated by the palmitoyl-LP, as opposed to a Th2 response generated by its cholesterol-LP analog. The palmitoyl-LP was efficiently taken up in vitro by immature dendritic cells (DC) in a time- and dose-dependent manner, and induced phenotypic maturation and production of pro-inflammatory cytokines by DC. Finally, DC stimulated with the palmitoyl-LP induced antigen-specific T cell responses through the Toll-like receptor-2 pathway. These findings have important implications for the development of effective lipopeptide immunization strategies against infectious pathogens.

Peptide-protein microarrays for the simultaneous detection of pathogen infections.

We describe novel peptide-protein microarrays, which were fabricated using semicarbazide glass slides that permitted the immobilization of glyoxylyl peptides by site-specific ligation and the immobilization of proteins by physisorption. The arrays permitted the simultaneous serodetection of antibodies directed against hepatitis C virus (HCV core p21 15-45 peptide, NS4 1925-1947 peptide, core, NS3, NS4, and mixture of core, NS3, NS4, and NS5 antigens), hepatitis B virus (HBc, HBe, and HBs), human immunodeficiency virus (Gp41 and Gp120 for HIV-I and Gp36 for HIV-II), Epstein-Barr virus (VCAp18 153-176 peptide), and syphilis (rTpN47 and rTpN17) antigens using an immunofluorescence assay. Peptide-protein microarrays displayed high signal-to-noise ratios, sensitivities, and specificities for the detection of antibodies as revealed by the analysis of a collection of human sera referenced against these five pathogens.

Lipid vector for the delivery of peptides towards intracellular pharmacological targets.

The ability of single-chain lipopeptides to gain access to cellular compartments other than those related to degradation/recycling was first deduced from their capacity to deliver peptide antigens into MHC-class I loading mechanisms. The ability of lipopeptides to escape complete endosome degradation was further illustrated by the selective inhibition of different protein kinase C isoenzymes and, more recently, the presentation of agonistic activity towards the interferon gamma receptor. Taken together, several independent results indicate that modification of a peptide by a single lipid chain confers upon it intracellular trafficking properties that can be used to deliver functional cargo peptides into living cells; the endoplasmic reticulum, cytosolic protease activity, sites of kinase activity, or even the signalling pathway associated with cytokine stimulation, all appear accessible to peptide modified by a single lipidic moiety. In this context, the interferon gamma receptor can be considered as a very discriminative pharmacological model, useful for the comparative evaluation of the cellular delivery of lipopeptides, as it allows the unambiguous tracking of their intact delivery into a wide range of cellular compartments. This model is now being used to probe the influence of the nature of the lipid moiety on the trafficking properties of lipopeptides.

Long-term specific immune responses induced in humans by a human immunodeficiency virus type 1 lipopeptide vaccine: characterization of CD8+-T-cell epitopes recognized.

We studied the effect of booster injections and the long-term immune response after injections of an anti-human immunodeficiency virus type 1 (HIV-1) lipopeptide vaccine. This vaccine was injected alone or with QS21 adjuvant to 28 HIV-uninfected volunteers. One month later, after a fourth injection of the vaccine, B- and T-cell anti-HIV responses were detected in >85% of the vaccinated volunteers. One year after this injection, a long-term immune response was observed in >50% of the volunteers. At this point, a positive QS21 effect was observed only in the sustained B-cell and CD4(+)-T-cell responses. To better characterize the CD8(+)-T-cell response, we used a gamma interferon enzyme-linked immunospot method and a bank of 59 HIV-1 epitopes. For the six most common HLA molecules (HLA-A2, -A3, -A11, -A24, -B7 superfamily, and -B8), an average of 10 (range, 3 to 15) HIV-1 epitopes were tested. CD8(+)-T-cell responses were evaluated according to the HLA class I molecules of the volunteers. Each assessment was based on 18 HIV-1 epitopes in average. We showed that 31 HIV-1 epitopes elicited specific CD8(+)-T-cell responses after vaccination. The most frequently recognized peptides were Nef 68-76 (-B7), Nef 71-79 (-B7), Nef 84-92 (-A11), Nef 135-143 (-B7), Nef 136-145 (-A2), Nef 137-145 (-A2), Gag 259-267 (-B8), Gag 260-268 (-A2), Gag 267-274 (-A2), Gag 267-277 (-B7), and Gag 276-283 (A24). We found that CD8(+)-T-cell epitopes were induced at a higher number after a fourth injection (P < 0.05 compared to three injections), which indicates an increase in the breadth of HIV CD8(+)-T-cell epitope recognition after the boost.

Identification of novel immunodominant CD4+ Th1-type T-cell peptide epitopes from herpes simplex virus glycoprotein D that confer protective immunity.

The molecular characterization of the epitope repertoire on herpes simplex virus (HSV) antigens would greatly expand our knowledge of HSV immunity and improve immune interventions against herpesvirus infections. HSV glycoprotein D (gD) is an immunodominant viral coat protein and is considered an excellent vaccine candidate antigen. By using the TEPITOPE prediction algorithm, we have identified and characterized a total of 12 regions within the HSV type 1 (HSV-1) gD bearing potential CD4(+) T-cell epitopes, each 27 to 34 amino acids in length. Immunogenicity studies of the corresponding medium-sized peptides confirmed all previously known gD epitopes and additionally revealed four new immunodominant regions (gD(49-82), gD(146-179), gD(228-257), and gD(332-358)), each containing naturally processed epitopes. These epitopes elicited potent T-cell responses in mice of diverse major histocompatibility complex backgrounds. Each of the four new immunodominant peptide epitopes generated strong CD4(+) Th1 T cells that were biologically active against HSV-1-infected bone marrow-derived dendritic cells. Importantly, immunization of H-2(d) mice with the four newly identified CD4(+) Th1 peptide epitopes but not with four CD4(+) Th2 peptide epitopes induced a robust protective immunity against lethal ocular HSV-1 challenge. These peptide epitopes may prove to be important components of an effective immunoprophylactic strategy against herpes.