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CD8+ cytotoxic T lymphocytes (CTLs) are critical for clearing many viral infections, and protective CTL memory can be induced by vaccination with attenuated viruses and vectors. Non-replicating vaccines are typically potentiated by the addition of adjuvants that enhance humoral responses, however few are capable of generating CTL responses. Adjuplex is a carbomer-lecithin-based adjuvant demonstrated to elicit robust humoral immunity to non-replicating antigens. We report that mice immunized with non-replicating Adjuplex-adjuvanted vaccines generated robust antigen-specific CTL responses. Vaccination by the subcutaneous or the intranasal route stimulated systemic and mucosal CTL memory respectively. However, only CTL memory induced by intranasal vaccination was protective against influenza viral challenge, and correlated with an enhancement of memory CTLs in the airways and CD103+ CD69+ CXCR3+ resident memory-like CTLs in the lungs. Mechanistically, Myd88-deficient mice mounted primary CTL responses to Adjuplex vaccines that were similar in magnitude to wild-type mice, but exhibited altered differentiation of effector cell subsets. Immune potentiating effects of Adjuplex entailed alterations in the frequency of antigen-presenting-cell subsets in vaccine draining lymph nodes, and in the lungs and airways following intranasal vaccination. Further, Adjuplex enhanced the ability of dendritic cells to promote antigen-induced proliferation of naïve CD8 T cells by modulating antigen uptake, its intracellular localization, and rate of processing. Taken together, we have identified an adjuvant that elicits both systemic and mucosal CTL memory to non-replicating antigens, and engenders protective CTL-based heterosubtypic immunity to influenza A virus in the respiratory tract. Further, findings presented in this manuscript have provided key insights into the mechanisms and factors that govern the induction and programming of systemic and protective memory CTLs in the respiratory tract. [ABSTRACT FROM AUTHOR]

Objective To describe five cases of protozoal keratitis or conjunctivitis in dogs with chronic preexisting ocular surface disease treated with long-term immunosuppression. Animals studied Five dogs that developed corneal or conjunctival mass lesions. Procedures The database of the Comparative Ocular Pathology Laboratory of Wisconsin was searched for canine cases diagnosed with corneal or conjunctival protozoal infection. Five cases were identified, and tissues were examined using routine and special histochemical stains: immunohistochemical labels for Neospora caninum, Toxoplasma gondii, and Leishmania spp., and tissue sample PCR for Leishmania spp. , Trypanosoma cruzi, tissue coccidia (i.e., T. gondii/Sarcocystis/Neospora), piroplasms, trichomonads, and Acanthamoeba. Electron microscopy was performed for two cases, and serology for N. caninum and T. gondii was available for three cases. Results Preexisting ocular diseases included keratoconjunctivitis sicca and pigmentary keratitis ( n = 4) and pyogranulomatous meibomian adenitis ( n = 1). All dogs were treated with tacrolimus or cyclosporine for at least 1.2 years. Dogs were presented with fleshy corneal or conjunctival masses that were clinically suspected to be neoplastic ( n = 4) or immune mediated ( n = 1). Histologic examination revealed granulomatous inflammation with intralesional protozoal organisms. Amoeba ( n = 2), T. gondii ( n = 2), or Leishmania mexicana ( n = 1) were identified using molecular techniques. Serological tests were negative. Conclusions Protozoal keratitis and conjunctivitis without systemic involvement appears rare and may be associated with chronic preexisting ocular surface disease treated with long-term immunosuppression. Based upon clinical appearance, lesions could be confused with neoplasia. This is the first report of amoebic keratoconjunctivitis in dogs and of L. mexicana in dogs in the United States. [ABSTRACT FROM AUTHOR]

Variants of the Bach2 gene are linked to vitiligo, celiac disease, and type 1 diabetes, but the underlying immunological mechanisms are unknown. In this study, we demonstrate that Bach2 plays crucial roles in maintaining T cell quiescence and governing the differentiation, activation, and survival of Foxp3+ regulatory T (Treg) cells. Bach2-deficient T cells display spontaneous activation and produce elevated levels of Thl/Th2-type cytokines. Without Bach2, Treg cells exhibit diminished Foxp3 expression, depleted numbers, hyperactivation, enhanced proliferation, and profound loss of competitive fitness in vivo. Mechanistically, reduced survival of Bach2-deficient Treg cells was associated with reduced Bcl-2 and Mcl-I levels and elevated Bim/Bcl-2 ratio. Additionally, Baeh2 deficiency induced selective loss of Helios-Foxp3+ Treg cells and a Treg cell transcriptome skewed toward the Thl/Th2 effector program at the expense of the Treg program. In vitro experiments confirmed that Bach2: 1) is indispensable for TCR/ TGF-β-induced Foxp3 expression; and 2) mitigates aberrant differentiation of Treg cells by repression of the competing Gata3- driven Th2 effector program. Importantly, perturbations in the differentiation of induced Treg cells was linked to a fatal Th2-type chronic inflammatory lung disease in Bach2-deficient mice. Thus, Bach2 enforces T cell quiescence, promotes the development and survival of Treg lineage, restrains aberrant differentiation of Treg cells, and protects against immune-mediated diseases. [ABSTRACT FROM AUTHOR]

Gossypol, a secondary metabolite found in cotton (Gossypium spp.), is known to be toxic to a variety of animals, particularly monogastric mammals and commercial poultry (Gallus domesticus). Gossypol toxicosis in poultry include reduced weight, decreased egg production, and egg yolk discolouration. However, there is limited published data regarding gossypol toxicity in northern bobwhites (Colinus virginianus), which may encounter cottonseed products in the environment and subsequently ingest gossypol. We determined the oral LD50 of gossypol in northern bobwhites following the Environmental Protection Agency's OCSPP 850.2100 Guideline: Avian Acute Oral Toxicity Test. Through a range-finding test, we estimated that the LD50 was between 200 and 1,000 mg/kg body weight (BW). Following the range-finding test, we administered a single oral dose of refined gossypol to quail at 262, 342, 447, 585, and 765 mg/kg BW. We observed quail daily for mortality and any signs of intoxication throughout a 14-day observation period. We performed gross necropsies and had histopathology done on select organ tissues from experimental animals. Using the probit analysis, we determined that the oral LD50 of gossypol in northern bobwhites is 651 mg/kg BW (95% CI 579–731). Hepatocellular pigment accumulation and pancreatic necrosis were important lesions interpreted as evidence of gossypol toxicity. [ABSTRACT FROM AUTHOR]

Background Sulfonamide hypersensitivity has a high incidence in HIV infection and correlates with low CD4+ counts, but the mechanisms are not understood. The aims of this study were to determine whether trimethoprim/sulfamethoxazole (TMP/SMX) led to SMX adduct formation, immunogenicity, or signs of drug hypersensitivity in SIV-infected rhesus macaques, and whether differences in antioxidants, pro-inflammatory mediators, or SMX disposition were predictive of drug immunogenicity. Methods Nine macaques chronically infected with SIVmac239 and 7 non-infected controls were studied. Baseline blood ascorbate, glutathione, IFN-γ, LPS, sCD14, and cytochrome b 5 reductase measurements were obtained, macaques were dosed with TMP/SMX (120 mg/kg/day p.o. for 14 days), and SMX metabolites, lymph node drug adducts, drug-responsive T cells, and anti-SMX antibodies were measured. Results Four of 9 of SIV-positive (44%), and 3 of 7 SIV negative (43%) macaques had drug-responsive T cells or antibodies to SMX. Two macaques developed facial or truncal rash; these animals had the highest levels of lymph node drug adducts. Antioxidants, pro-inflammatory mediators, and SMX metabolites were not predictive of drug immunogenicity; however, the Mamu DRB1*0401/0406/0411 genotype was significantly over-represented in immune responders. Conclusions Unlike other animal models, macaques develop an immune response, and possible rash, in response to therapeutic dosages of TMP/SMX. Studying more animals with CD4+ counts <200 cells/μl, along with moderately restricted ascorbate intake to match deficiencies seen in humans, may better model the risk of SMX hypersensitivity in HIV-infection. In addition, the role of Mamu-DRB1 genotype in modeling drug hypersensitivity in retroviral infection deserves further study. [ABSTRACT FROM AUTHOR]

Case Description--6 dogs (10 eyes) with keratitis following long-term topical treatment with a carbonic anhydrase inhibitor (CAI) were evaluated. In 4 dogs (6 eyes), CAI treatment was discontinued. Three dogs (4 eyes) underwent enucleation because of end-stage corneal disease. One dog was treated differently in each eye and thus was represented in both aforementioned groups. Clinical Findings--Following initiation of treatment with a CAI (ie, brinzolamide or dorzolamide), the median time to development of severe ocular signs was 266 days (range, 133 to 679 days). Clinically severe ocular signs included ulcerative and nonulcerative perilimbal keratitis or severe diffuse keratitis with marked vascularization.The keratitis was refractory to treatment with anti-inflammatory medications. Histologic and immunohistochemical examination of enucleated globes was performed in 3 affected dogs and in 1 dog with keratitis that recovered. Corneal lesions included 2 distinct inflammatory infiltrates with plasma cells predominating in the anterior stroma and both T cells and neutrophils in the epithelium. Stromal plasma cells and overlying epithelium exhibited strong positive immunoreactivity for IgG. Treatment and Outcome--Topical CAI treatment was discontinued in 4 dogs after a median of 209 days (range, 44 to 433 days), and in these dogs, clinical improvement was evident within 2 to 4 days of CAI treatment cessation. Signs of keratitis resolved in 12 to 25 days in these 4 dogs, and median follow-up time after CAI discontinuation was 25.5 months (range, 6 to 42 months), during which time signs of corneal disease did not recur. Clinical Relevance--On the basis of this small series, presumed topical CAI-associated keratitis in dogs appeared to be an uncommon immune-mediated disease that was not responsive to corticosteroid treatment. Affected patients improved rapidly, but only after discontinuation of CAI treatment. In dogs with glaucoma, clinicians should consider the development of punctate keratopathy and severe diffuse keratitis as potential adverse effects related to topical administration of CAIs, even after previously uneventful long-term use. [ABSTRACT FROM AUTHOR]