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B T Rouse

Publications and source records attributed to B T Rouse.

At least 91 records · Page 5Linked to original sources
PubMed1995

Vaccination with recombinant vaccinia viruses expressing ICP27 induces protective immunity against herpes simplex virus through CD4+ Th1+ T cells.

This study was designed to evaluate the efficacy and mechanisms of protection mediated by recombinant vaccinia viruses encoding immediate-early (IE) proteins of herpes simplex virus type 2 (HSV-2). Three mouse strains were immunized against the IE proteins ICP27, ICP0, and ICP4, and mice were challenged intracutaneously in the zosteriform model with HSV-2 strain MS. Protection was observed only following immunization with the ICP27 construct and then only in the BALB/c mouse strain. Protection in BALB/c mice was ablated by CD4+ T-cell suppression but remained intact in animals depleted of CD8+ T cells. Moreover, protection could be afforded to SCID nude recipients with CD4+ but not CD8+ T cells from ICP27-immunized mice. Only BALB/c mice developed a delayed-type hypersensitivity reaction to HSV-2, and in vitro measurements of humoral and cell-mediated immunity revealed response patterns to ICP27 and HSV that differed between protected BALB/c and unprotected mouse strains. Accordingly, BALB/c responses showed antigen-induced cytokine profiles dominated by type 1 cytokines, whereas C57BL/6 and C3H/HeN mice generated cytokine responses mainly of the type 2 variety. Our results may indicate that protection against zosterification is mainly mediated by CD4+ T cells that express a type 1 cytokine profile and that protective vaccines against HSV which effectively induce such T-cell responses should be chosen.

Animals↗
PubMed1994

CD4+CD8- T cells are the effector cells in disease pathogenesis in the scurfy (sf) mouse.

Mice hemizygous for the X-linked mutation, scurfy (sf), exhibit a fatal lymphoreticular disease that is mediated by T lymphocytes. To evaluate the respective roles of CD4 or CD8 single positive T cells in scurfy disease, neonates were treated with mAbs directed against the CD4 or CD8 molecules. Whereas mice treated with an anti-CD8 Ab developed lesions and succumbed to disease at the same time (17 days) as their untreated scurfy littermates, mice treated with an anti-CD4 Ab lived up to 11 wk before developing scurfy disease. To insure a more complete elimination of the T cell subsets, the scurfy mutation was bred onto beta 2-microglobulin (beta 2m)-deficient (CD8-less) and CD4-deficient transgenic mouse lines. Whereas there was little moderation of disease in beta 2m-deficient scurfy mice, CD4-deficient scurfy mice had markedly decreased scurfy lesions and a prolonged life span, similar to that of anti-CD4-treated sf/Y mice. Additionally, scurfy disease was transplanted into H-2-compatible nude mice through the adoptive transfer of CD4+CD8- T cells, but not CD4-CD8+ T cells. Flow-cytometric analysis revealed that sf/Y mice have an increased percentage of activated CD4+ T cells in their lymph nodes. In addition, there is an increase in the in vitro production of cytokines in the cultured splenocytes of CD8-less, but not CD4-less, scurfy mice. These data suggest that CD4+ T cells are critical mediators of disease in the scurfy mouse.

Animals↗
PubMed1994

Dysregulation of cytokine expression in monocytes from HIV-positive individuals.

Because HIV may alter the production of inflammatory factors produced by monocytes, the expression of tumor necrosis factor alpha (TNF-alpha), tissue factor (TF), interleukin (IL)-1 beta, and IL-6 was evaluated in 47 HIV-seropositive persons and seronegative control subjects. RNA was extracted from freshly isolated lipopolysaccharide (LPS)-stimulated or unstimulated monocytes. Cytokine and TF expression was quantitated by dot blot hybridization or a reverse transcription polymerase chain reaction (RT-PCR). A significant depression of TF mRNA was observed in LPS-stimulated monocytes (66% less in AIDS, 20% less in AIDS-related complex (ARC), and 0% less in asymptomatic patients), whereas normal responses were observed for TNF-alpha, IL-1 beta, and IL-6. When constitutive expression was measured in unstimulated monocytes by RT-PCR, a differential pattern was also observed. TNF-alpha and IL-1 beta were positive in 85% of asymptomatic persons, compared with only 27% of ARC and 42% of AIDS patients. Expression of IL-6 was observed in lower proportions, 27-30%, with no significant differences among disease states. All samples were negative for TF. Thus, the regulation of inflammatory molecules is differentially altered in individuals with HIV infection. TF is preferentially down-regulated, compared with TNF-alpha, IL-1 beta, and IL-6, in LPS-stimulated monocytes as patients progress to AIDS. TNF-alpha and IL-1 beta are preferentially up-regulated, compared with IL-6 and TF, in unstimulated monocytes in asymptomatic persons, with a loss of up-regulation as patients progress to AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Vaccination with the immediate-early protein ICP47 of herpes simplex virus-type 1 (HSV-1) induces virus-specific lymphoproliferation, but fails to protect against lethal challenge.

Assessing the immunobiological function of the individual proteins of herpes simplex virus-type 1 (HSV-1) continues to be important in elucidating virus-host interactions and for the rational design of subunit vaccines. In this report, the non-structural, immediate-early protein ICP47 of HSV-1 was examined for its ability to induce virus-specific immune responses. The ICP47 protein, when expressed from a recombinant vaccinia virus or when produced by cell-free, in vitro translation, induced a vigorous HSV-1-specific lymphoproliferative response. However, other common parameters of immunity such as neutralizing antibody, delayed-type hypersensitivity, and class I major histocompatibility complex (MHC)-restricted cytotoxic T lymphocytes (CTL) were not induced by ICP47. Moreover, mice immunized with vaccinia-expressed ICP47 were unable to survive lethal challenge with virulent HSV, indicating that in spite of its ability to induce significant HSV-1-specific lymphoproliferation, ICP47 appears unable to afford protective immunity in vivo. Possible reasons for this failure and the implications of these results in terms of vaccine design are discussed.

Animals↗
PubMed1994

Quantitative studies on CD4+ and CD8+ cytotoxic T lymphocyte responses against herpes simplex virus type 1 in normal and beta 2-m deficient mice.

Against herpes simplex virus type 1 (HSV-1) infected target cells, effector T cells of both CD4- CD8+ and CD4+ CD8- phenotypes occur in both man and mice. In man, the CD4+ CD8- phenotype may dominate the response, but the situation in the mouse is unclear. In this report, several approaches are used to document the existence of HSV-1-specific cytotoxic T lymphocytes (CTL) of both phenotypes and to quantitate the frequency of their CTL precursors (CTL-p) in acutely HSV-1 infected animals. Evidence that CD4+ CD8- CTL occur was confirmed with beta 2-m- mice lacking CD8+ T cells and which generated CTL capable only of lysing MHC class II infected target cells. Comparisons of frequencies of CD4+ CD8- and CD4- CD8+ CTL-p showed the former to be 2-3-fold more frequent. The beta 2-m- mice generated only CD4+ CD8- CTL-p and their frequencies approximately equally the CD4+ CD8- CTL-p frequency in intact infected mice. Our results are discussed in terms of the value of the mouse model to study HSV-1 immunobiology.

Animals↗
PubMed1994

Induction in vitro of primary cytotoxic T-lymphocyte responses with DNA encoding herpes simplex virus proteins.

Vaccines which successfully protect against virus infections usually need to induce a broadly reactive immune response which includes the induction of cytotoxic T lymphocytes (CTL). In this study, we have used a convenient in vitro approach to investigate if plasmid DNAs encoding proteins of herpes simplex virus (HSV) are capable of inducing primary CD8+ CTL. Dendritic cells or macrophages were transfected with either plasmid DNA encoding glycoprotein B or DNA encoding the immediate-early protein ICP27. These antigen-presenting cells (APC) were then used to stimulate enriched populations of naive T cells in microcultures for 5 days in vitro. Antigen-specific CD8+ CTL which reacted both with specific protein-expressing targets and with syngeneic targets infected with HSV could be demonstrated. Dendritic cells, as APC, generated the maximal responses, but such cells needed to be transfected with DNA in the presence of a cationic lipid. However, macrophages could act as APC when they were exposed to purified DNA. HSV-primed splenocytes were also shown to generate specific CTL responses when they were stimulated with purified DNA encoding ICP27. The novel approach described in this paper promises to be extremely useful, since defining immunogenicity profiles and identifying epitopes on viral proteins should be easier and more convenient when working with DNA and investigating variables in vitro. This is particularly the case with complex viruses such as HSV, most of whose encoded proteins have yet to be isolated in sufficient quantity or purity to perform in vivo immunological studies.

Animals↗
PubMed1994

Cytotoxic T lymphocyte response to herpes simplex virus type 1 is composed of both CD8+ and CD4+ T cell phenotypes in acute and memory states.

Mice were infected via the cornea with HSV-1. Next, draining lymph nodes (DLN) and spleen cells were analyzed at various times post infection for the presence of cytotoxic T lymphocyte precursors (CTL-p) of both the CD8+ and CD4+ phenotypes. Responses were greatest in the DLN, but memory CTL persisted in the spleen and were undetectable in DLN by 60 days. On all occasions, the frequency of CD8+ CTL outnumbered CD4+ CTL. The murine CTL responses to HSV-1 differ from those in man where CD4+ MHC class II restricted CTL appear to dominate the response at least in the memory phase.

Acute Disease↗
PubMed1994

Transplantation of T cell-mediated, lymphoreticular disease from the scurfy (sf) mouse.

The X-linked mutation, scurfy (sf), causes a fatal lymphoreticular disease characterized by runting, lymphadenopathy, splenomegaly, hypergammaglobulinemia, exfoliative dermatitis, Coombs'-positive anemia, and death by 24 days of age. T lymphocytes are required to mediate this syndrome as shown by a total absence of disease in mice bred to be scurfy and nude (sf/Y; nu/nu). The scurfy phenotype is not transmitted by sf/Y bone marrow transplants, though cells of scurfy origin do reconstitute all lymphoid organs in the recipient mouse. These data suggest that scurfy disease results from an abnormal T cell development process and not from an intrinsic stem cell defect. We therefore tested the ability of transplanted scurfy thymuses to transmit scurfy disease to congenic euthymic mice, to athymic (nude) mice, and to severe combined immunodeficiency (SCID) mice. Euthymic recipients of sf/Y thymic grafts remained clinically normal as did all SCID and nude recipients of normal thymus transplants. Morphological lesions similar to those found in scurfy mice occurred in all H-2-compatible nude and SCID recipients of sf/Y thymic grafts. Intraperitoneal injections of scurfy thymocytes, splenocytes, and lymph node cells also transmitted the scurfy phenotype to H-2-compatible nude mice and SCID mice. Our findings indicate that scurfy disease can be transmitted to T cell-deficient mice by engraftment of scurfy T cells, but that pathogenic scurfy T cell activities can be inhibited (or prevented) in immunocompetent recipient mice.

Animals↗
PubMed1994

Cholera toxin acts as a potent adjuvant for the induction of cytotoxic T-lymphocyte responses with non-replicating antigens.

Cholera toxin (CT) is a strong systemic and mucosal adjuvant that greatly enhances IgG and IgA immune responses, but its adjuvant effects for cellular immunity, particularly class I-restricted cytotoxic T lymphocyte (CTL) responses, are less well understood. In the present report, CT and the purified non-toxic B component (CTB) were assessed for their ability to facilitate class I-restricted CTL induction to soluble proteins as well as to permit sensitization of target cells for CTL-mediated lysis. Priming for ovalbumin (OVA)-specific CTL occurred following oral exposure to a combination of OVA with CT plus CTB. In addition, CTB mixed with soluble proteins and administered intravenously primed mice for antigen-specific class I-restricted CTL. Target cells could also be sensitized for CTL-mediated killing following their exposure to soluble antigen and CTB in vitro. These results indicate that combinations of CT and CTB not only enhance antibody responses, but also have an immunomodulating effect to allow sensitization and priming for antigen-specific class I-restricted CTL.

Adjuvants, Immunologic↗
PubMed1994

Differential expression of tumor necrosis factor alpha and interleukin 1 beta compared with interleukin 6 in monocytes from human immunodeficiency virus-positive individuals measured by polymerase chain reaction.

Expression of tumor necrosis factor alpha (TNF alpha), interleukin 1 beta (IL-1 beta), and interleukin 6 (IL-6) was evaluated in unstimulated peripheral blood monocytes obtained from human immunodeficiency virus-positive (HIV+) individuals using a reverse transcription-polymerase chain reaction (RT-PCR) method. In all, 40 subjects were included--13 asymptomatic, 11 with ARC, seven with AIDS, and nine HIV- controls. Of the asymptomatic individuals, 85% were positive for TNF alpha and IL-1 beta compared with only 27% of the ARC and 42% of the AIDS patients. Expression of IL-6 message was observed in lesser proportions, with no significant differences among disease states. Quantitation of IL-1 beta and TNF alpha mRNA from the positive samples fell into two categories, low responders (six of 17), with < 5,000 copies of IL-1 beta and TNF alpha mRNA, and high responders (11 of 17), with > 5,000 copies per 10 pg of total cellular RNA. There was no correlation of mRNA detection or concentration with CD4+ cell number or beta 2-microglobulin levels. However, the levels of mRNA, but not its presence alone, were positively correlated with neopterin levels. The data show differential cytokine regulation in monocytes, observed as an increase in the expression of TNF alpha and IL-1 beta compared with IL-6 in HIV+ patients. Our report also emphasizes the utility of an RT-PCR system in analyzing multiple cytokine transcript levels in small amounts of clinical materials.

AIDS-Related Complex↗
PubMed1993

Limitations and modifications of quantitative polymerase chain reaction. Application to measurement of multiple mRNAs present in small amounts of sample RNA.

Quantification of mRNA by polymerase chain reaction (PCR) is performed by using a competitor DNA standard in the PCR or by employing an internal standard RNA following simultaneous reverse transcription (RT) with the sample RNA. The latter approach is more reliable since it accounts for variations in both the RT and PCR steps. However, we describe in this report that at times the internal standard RNA competes with the target mRNA in the PCR when both are present in disproportionate concentrations in the initial simultaneous RT reaction. To overcome the competition in the PCR, multiple simultaneous RT reactions with the sample RTA and the internal standard RNA are required. Such procedures make the approach time consuming and restrict the use of internal standard RNA for quantification of multiple mRNAs present in small amounts of sample RNA. These limitations are circumvented by the competitor DNA standard approach and mRNA levels can be quantified by calculating the RT efficiency. We illustrate the situations by quantifying the levels of IL-2, IL-4, IL-5, IFN-gamma, and beta-actin mRNAs in mitogen stimulated murine T cells using a multiple mRNA specific internal standard.

Animals↗
PubMed1993

Isolation and functional studies on feline bone marrow derived macrophages.

In this report, we describe an in vitro culture method for feline bone marrow cells, which yields large numbers of quiescent macrophages after 14 days of culture. The bulk of the cultured cell population consists of macrophages as assessed by morphology, macrophage specific cytochemistry, and phagocytosis. The remaining cells were lymphocytes, bone marrow stromal cells, fibroblasts and occasional polymorphonuclear leukocytes. While resting cells produced no detectable interleukin 1, stimulation with lipopolysaccharide (LPS) induced the production of biologically active interleukin 1. After 6 h LPS stimulation, mRNA for tumor necrosis factor alpha and interleukin 1 beta was detectable. The absence of mRNA in unstimulated cells indicates cultured macrophages were not activated until stimulated by LPS or plastic adherence. This approach provides a useful means to measure potential modulatory effects by virus infections or other agents upon feline macrophage gene expression.

Animals↗
PubMed1993

The current status of viral immunology.

Many aspects of viral immunity, ranging from the molecular and cellular studies of the interaction between viruses and host cells in vitro and the crystalline structures of the MHC and peptides, to the regulation of pathogenesis in experimental animals and humans were discussed at a recent meeting.

Allergy and Immunology↗
PubMed1993

The proportion of herpes simplex virus-specific cytotoxic T lymphocytes (Tc) that recognize glycoprotein C varies between individual mice and is dependent on the form of immunization.

In mice the immune response to HSV-1 includes a brisk Tc response that is intimately associated with the control of infection. This report evaluated the Tc response to gC, one of the envelope glycoproteins of HSV-1. This protein was recognized as a target antigen for Tc from HSV-1 immune mice only if they expressed the H-2Kb MHC allele. However, even within these "responder" strains of mice the proportion of gC specific Tc was highly variable. The failure of HSV-induced Tc to recognize gC in the context of other class 1 MHC haplotypes (H-2d and H-2k) was demonstrable at the clonal level and could not be attributed to peculiarities of the recombinant constructs. Surprisingly, despite the inability of H-2k-restricted, HSV-1-induced Tc to recognize gC, when a vaccinia gC virus construct was used to immunize H-2k strains of mice it showed a variable ability to induce memory Tc populations capable of lysing HSV-1-infected autologous cells. Of added importance was the correlation of this induced Tc response with optimum protection against subsequent challenge with HSV-1. This demonstrated that despite the presence of suitable epitopes, the context of the immunogen would also influence its ability to induce Tc. Consequently, the potential repertoire of available HSV-1-specific Tc specificities is larger than indicated by studying animals immunized with HSV.

Animals↗
PubMed1993

Efficacy of the herpes simplex virus types 1 and 2 mutant viruses to confer protection against zosteriform spread in mice.

Two mutant viruses, HSV-2 XD192 and HSV-1 1716, failed to generate zosteriform lesions when injected in high dose into BALB/c and C3H mice. Mice exposed to mutant viruses were solidly immune to challenge by wild-type homologous or heterologous virus. However, at lower immunizing doses protection was evident against lethality, but not skin lesions, especially in the case of mutant XD192. Protection could be conferred with lymphoid cells from mutant virus immune mice and again, protection against lethality was more frequent than prevention of skin lesions. On the basis of cell fractionation studies, protection against lethality was assumed to be principally the function of CD8+ T lymphocytes. The implications of the results in terms of vaccine development were briefly discussed.

Animals↗
PubMed1993

Recognition by and in vitro induction of cytotoxic T lymphocytes against predicted epitopes of the immediate-early protein ICP27 of herpes simplex virus.

The identification of herpes simplex virus type 1 (HSV-1) proteins and the minimal epitopes within these proteins which serve as targets for cytotoxic T lymphocytes (CTL) remains an important goal for the development of effective vaccine strategies. In this report, an H-2Kd allele-specific peptide-binding motif was used to locate putative CTL epitopes in the HSV-1 immediate-early protein ICP27, a protein previously identified as a major CTL target in the BALB/c mouse. Peptides 1 (amino acids 322 to 332) and 2 (amino acids 448 to 456) synthesized to represent two separate predicted CTL epitopes in ICP27 were able to sensitize target cells in vitro for recognition by HSV-1-specific CTL. Moreover, using a recently developed system to generate primary CTL responses in vitro, both peptides induced primary CTL which reacted with target cells expressing HSV-1. This system allowed us to verify the activity of two CTL epitopes in the ICP27 protein and holds promise as a rapid way of identifying immunogenic peptides from any protein molecule.

Animals↗