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Vaccinology, immunology, and comparative pathogenesis of measles in the quest for a preventative against AIDS.

Current approaches to the prevention and control of AIDS by vaccines and by chemotherapy have failed to provide satisfactory solutions to this important medical problem and have failed, in addition, to provide definitive guidelines for future research endeavor. Vaccine research must and will continue but it is possible that a safe and effective vaccine may never be developed and it may be timely to explore, in addition, alternative means for immunological intervention in AIDS. Both immunoprophylactic and immunotherapeutic efforts might be assisted by manipulating the T helper 1 (Th1) and T helper 2 (Th2) subsets of CD4+ T helper cells, which is therefore worthy of exploration. Selective control of immune response by the two T helper subsets is by release of different cytokines that promote either cellular or humoral immunity, the latter of which may be associated with inappropriate immune responses and with immune dysfunction. Discovery of the Th1 and Th2 subsets and definition of the cytokines they release provide a new avenue toward possible development of a safe and effective vaccine and an approach, in addition, to correction of immune dysfunction by selective cytokine administration or by cytokine ablation by antagonists or antibodies. AIDS pathogenesis and immune dysfunction are complex and understanding them may be overwhelmed by an excess of possibilities. Simplification of the endeavor might benefit from comparative studies of the pathogenesis of measles, in which there also is immune deficiency but usually with spontaneous viral clearance, reversal of immune dysfunction, and total recovery. In addition, measles presents as a single disease and is caused by antigenically stable virus. Identification of the process whereby measles immunodeficiency is spontaneously reversed might be of importance in attempting to devise means for similar reversal in AIDS.

AIDS Vaccines↗

[Respective indications of enteral or parenteral nutrition during pre- and post-operative periods].

Denutrition is often associated with poor postoperative outcome. However, a large body of evidence, from studies comparing perioperative parenteral (PN) or enteral (EN) nutrition to the absence of perioperative nutrition, suggests that perioperative nutritional support provides significant improvements in both nutritional status and postoperative clinical outcome in selected patients who are or will become malnourished. The aim of this study was to select and review all relevant articles comparing perioperative parenteral and enteral nutritional support, either in terms of clinical outcome, or risks and costs, or in pathophysiological terms. Twelve clinical reports were reviewed. All contained methodological flaws, mainly type II statistical error due to an insufficient number of patients, inaccurate primary diagnosis, absence of blinding, and lack of objective criteria of judgement. These concerns warrant caution in interpreting the results. Moderately strong (grade B) recommendations can only be drawn from these studies: PN (compared to early EN) is associated with a higher rate of sepsis in patients following abdominal trauma; EN is as efficient as PN in patients following surgery; EN is safe and cheaper than PN. PN formulae lack many important nutrients (glutamine, arginine, cysteine, peptides, fibers, n-3 polyunsaturated fatty acids, and nucleotides). Many experimental (animal) and some clinical (in non surgical patients) studies showed that PN (compared to EN) induces gut mucosal atrophy, liver dysfunction, gut bacterial translocation and immune dysfunction. The final aim of PN and EN would therefore strikingly differ. The qualitatively imperfect PN would only supply the fasting patient with quantitative amounts of calories and proteins. Due to initially limited digestive tolerance, EN provides less nutrition than PN does, but would finally lead to the same or even better outcome, due to its ability to counteract stress induced gut and immune dysfunction. Current evidence therefore suggests that early EN is superior to PN in trauma patients, and not different from but cheaper (and therefore more cost-effective) than PN in surgical patients. Further controlled, randomised, and blinded studies including sufficient sizes of groups are required, especially in the surgical setting, to address a large number of still unanswered questions.

Enteral Nutrition↗

Necrotizing herpetic retinopathies. A spectrum of herpes virus-induced diseases determined by the immune state of the host.

PURPOSE: Necrotizing herpetic retinopathies (NHR), a new spectrum of diseases induced by viruses of the herpes family (herpes simplex virus, varicella-zoster virus and cytomegalovirus), includes acute retinal necrosis (ARN) occurring in apparently immunocompetent patients and progressive outer retinal necrosis (PORN) described in severely immuno-compromised patients. Signs of impaired cellular immunity were seen in 16% of ARN patients in a review of 216 reported cases, indicating that immune dysfunction is not only at the origin of PORN but might also be at the origin of ARN. The aim of this study was to correlate clinical findings in NHR patients with their immunologic parameters. METHODS: Charts from patients with the diagnosis of ARN or PORN seen from 1990 to 1995 were reviewed. Clinical characteristics and disease patterns were correlated with immunological parameters taking into account CD4 lymphocyte rate in AIDS patients and blood-lymphocyte subpopulation determination by flow cytometry, cutaneous delayed type hypersensitivity testing and lymphocytic proliferation rate to seven antigens in HIV-negative patients. RESULTS: During the period considered, 11 patients and 7 patients fulfilled the criteria of ARN and PORN respectively. Immune dysfunctions were identified in most patients. Mild type of ARN and classical ARN were associated with discrete immune dysfunctions, ARN with features of PORN was seen in more immunodepressed patients and classical PORN was always seen in severely immunodepressed HIV patients. CONCLUSION: Our findings suggest that NHR is a continuous spectrum of diseases induced by herpes viruses, whose clinical expression depends on the immune state of the host going from mild or classical ARN at one end in patients with non-detectable or slight immune dysfunction to PORN in severely immunodepressed patients at the other end and with intermediary forms between these extremes.

AIDS-Related Opportunistic Infections↗

[Cyto-dynamic observations on T lymphocytes and the CSF in Guillain-Barre syndrome].

We have examined by ANAL for 107 times in 45 cases and the cytology of CSF in 92 times for acute infectious polyneuritis. The count of T-lymphocytes in severe and most severe types had a marked decrease comparing with the light and moderate types. The patients with a course of disease less than seven days had a significant decreasing to comparing with the more than seven days. The immune complex (IgG, IgM, Cs) had a distinct decreasing. The cytology of CSF showed that the lymphocytes were decreasing but the monocytes and the macrophages increased. We considered that there were not only cellular immunity dysfunction, but also the humoral immunity dysfunction. Using of hormones in this disease is not suitable.

Adolescent↗

Prevention of retrovirus-induced aberrant cytokine secretion, excessive lipid peroxidation, and tissue vitamin E deficiency by T cell receptor peptide treatments in C57BL/6 mice.

To test whether T cell receptor (TCR) peptide treatment can prevent immune dysfunction, excessive lipid peroxidation, and malnutrition caused by retrovirus infection, female C57BL/6 mice were infected with LP-BM5 retrovirus. Infection with retrovirus inhibited lymphocyte proliferation, cytokine release T helper 1 cells, stimulated cytokine secretion by T helper 2 cells, induced abnormal hepatic and cardiac lipid profiles, and produced excessive tissue lipid peroxidation with hepatic and cardiac vitamin E deficiency. Two weeks after infection, TCR peptides Vbeta5.2, Vbeta8.1, Vbeta8.1 + Vbeta5.2, Vbeta8.1(N), and Vbeta8.1 were injected to the mice at dose of 200 microg/mouse. Vbeta8.1 and Vbeta5.2 treatments largely maintained lymphocyte proliferation and IL-2 and IFN-gamma release, and prevented excessive IL-6, IL-10, and TNF-alpha secretion. Concomitantly, these treatments normalized hepatic and cardiac lipid profiles, reduced tissue lipid peroxidation, and thereby significantly maintained vitamin E in the liver and heart. Vbeta8.1 segments treatment did not prevent the immune dysfunction, abnormal lipid profile and lipid peroxidation, and vitamin E deficiency caused by the retrovirus infection. In conclusion, injection of intact TCR peptides during murine retrovirus infection largely prevented immune dysfunction by blocking the excessive stimulation of a T cell subset caused by retroviral superantigens. It also ameliorated malnutrition status by normalizing lipid profile, lipid peroxidation, and vitamin E deficiency. T cell immune dysfunction and its prevention by TCR peptide treatment is important in the therapy of vitamin E deficiency induced by retrovirus infection.

Amino Acid Sequence↗

Impact of aging on immune modulation by tumor.

Tumor development and aging can each alter immune competence. The present study aimed to determine the impact of Lewis lung carcinoma (LLC) presence on immune parameters of middle-aged (averaging 6.5 months) versus aged (averaging 21.3 months) mice. An age-associated decline in the CD4+ cell frequency was seen in freshly isolated spleen and lymph node cells, as well as in cultures stimulated with immobilized anti-CD3. This decline was not further exacerbated by tumor presence. What was prominently inhibited by tumor was the capacity of either splenic or lymph node CD4+ cells to become stimulated to express IFN-gamma. Spleen and lymph node cultures from aged tumor-bearing mice had the lowest frequency of CD4+IFN-gamma+ cells and the least amount of secreted IFN-gamma. CD8+ cells were not affected by aging, but tumor presence reduced the induction of CD8+IFN-gamma+ cells in lymph node cultures. We previously showed that LLC growth stimulates myelopoiesis, as seen by splenomegaly and the mobilization of immune inhibitory CD34+ progenitor cells. Tumor presence in middle-aged mice reduced spleen cell blastogenesis, which was mediated by CD34+ cells. Aged mice had reduced blastogenesis, and this was further reduced by presence of tumor. However, neither the age-associated immune dysfunction nor the tumor-induced immune suppression in aged mice was due to CD34+ progenitor cells. These studies show how tumor presence can further compromise the immune dysfunction that accompanies aging. In addition, they show that aging impacts on the mechanisms by which tumors inhibit T-cell capabilities, with myelopoiesis-associated CD34+ cells mediating the immune depression of middle-aged tumor-bearers and an independent mechanism being responsible for the immune depression in aged tumor-bearing mice.

Aging↗

Immunotoxicity of pesticides: perspectives and trends.

In recent years, great concern has been expressed about genotoxic potential of pesticide chemicals. These toxic chemicals have become an integral part of the ecosystem and the human health effects of these agents are yet to be satisfactorily defined. The objectives of this review is to examine the sources of information available; evaluation of experimental protocols employed for assessment of immunological effects; and to study specific cellular and molecular locus which could be responsible for impaired immune responsiveness. It is emphasized that threshold level for the pesticide effect below which no effect would be seen, depends on the animal species, the method of testing for immune responses and type of antigen used. A comparative assessment of immune responses using different antigens is, therefore, an important aspect of pesticide immunotoxicity. In view of widespread use, distribution and stability of some of these compounds in the environment, pesticide exposure may play a greater role in suspected fragile immune system, and may result in altered disease susceptibility. An understanding of these risks depends, to a great extent, upon cellular and molecular events underlying pesticide-induced immune alterations in experimental animals. It is, therefore, proposed that pesticide chemicals may influence humoral immunity while having no detectable effect on cell-mediated immunity (CMI); immune dysfunction is related to dose and duration of pesticide exposure; a single assay of immune function may not be appropriate to detect pesticide-induced immune dysfunction; since many immune responses are genetically controlled, alterations in responsiveness to one challenge in a given animal model may not hold true in second one; although it has been established that pesticide chemicals can alter immune function, the mechanisms of action have yet to be determined. This paper also reviews the effects of pesticide on lymphocyte function and suggests that lymphocyte dysfunction may be an integral part of pesticide-induced immunosuppression and presents an approach which may serve to delineate the possible mechanisms of action. It is quite clear that pesticide-induced immunomodulation endangers humans and animals. This hazard should, therefore, not to be underestimated in evaluation of toxicity of these chemicals. However, additional research is needed in basic mechanism of immunotoxicity and identification of susceptibility factors which predispose to these reactions.

Animals↗

Vitamins and immunomodulation in AIDS.

Acquired immune deficiency syndrome (AIDS) is a clinical disorder caused by a retrovirus infection and represents the end point in a progressive sequence of immunosuppressive changes. Vitamins can enhance disease resistance in animals and humans. As such they are important co-factors in optimal functioning of the immune systems. In this article, the immunological and nutritional modifications caused by AIDS are summarized. The effects of murine and human retrovirus infection on vitamin status are analyzed as co-factors in the development of severe immune dysfunction, AIDS. The properties of immunoenhancing antioxidative vitamins, vitamin A, B6, B12, C, E, and beta-carotene, which are frequently low in AIDS patients, are evaluated relative to the development of immunodeficiency during retrovirus infection. Vitamin A, E, and B12 deficiency accelerated the development of AIDS with low T cells, whereas their normalization retarded the development of immune dysfunction. The interactions between these vitamins and the immune system in human AIDS patients and animal models of AIDS are reviewed. Our purpose is to provide data on how retrovirus infection can cause nutritional deficiencies that accentuate immune damage and to evaluate the potential therapeutic role of vitamins in the treatment of immune dysfunctions in AIDS patients.

Acquired Immunodeficiency Syndrome↗

Immune system dysfunction and autoimmune disease in mice lacking Emk (Par-1) protein kinase.

Emk is a serine/threonine protein kinase implicated in regulating polarity, cell cycle progression, and microtubule dynamics. To delineate the role of Emk in development and adult tissues, mice lacking Emk were generated by targeted gene disruption. Emk(-/-) mice displayed growth retardation and immune cell dysfunction. Although B- and T-cell development were normal, CD4(+)T cells lacking Emk exhibited a marked upregulation of the memory marker CD44/pgp-1 and produced more gamma interferon and interleukin-4 on stimulation through the T-cell receptor in vitro. In addition, B-cell responses to T-cell-dependent and -independent antigen challenge were altered in vivo. As Emk(-/-) animals aged, they developed splenomegaly, lymphadenopathy, membranoproliferative glomerulonephritis, and lymphocytic infiltrates in the lungs, parotid glands and kidneys. Taken together, these results demonstrate that the Emk protein kinase is essential for maintaining immune system homeostasis and that loss of Emk may contribute to autoimmune disease in mammals.

Animals↗

Anti-inflammatory effects of theophylline: modulation of immune functions during murine leukemia virus infection.

LP-BM5 murine leukemia virus induces immune dysfunction leading to B cell leukemia and murine AIDS with cytokine dsyregulation. Theophylline induces apoptosis of leukemia cells in humans. Therefore the effects of theophylline on immune dysfunction in a murine model of leukemia were investigated. C57BL/6 mice consumed drinking water containing 0.3% theophylline beginning 2 weeks after murine retrovirus infection for 4 months. Theophylline largely prevented the retrovirus induced splenomagaly, lymphodenopathy, reduction in B and T cell proliferation, and suppression of Thl cytokines (IL-2) secretion. It also suppressed Th2 cytokine (IL-4, TNF-alpha, and IL-10) production, which was otherwise stimulated by retrovirus infection. These data suggest that immune dysfunction, induced by murine retrovirus infection, was largely prevented by theophylline treatment.

Animals↗

T-cell-receptor dose and the time of treatment during murine retrovirus infection for maintenance of immune function.

C57BL/6 mice were injected with different doses of human T-cell receptor (TCR) V beta 8.1 CDR1 peptide at different times after murine retrovirus (LP-BM5) infection. Injection with TCR V beta 8.1 CDR1 peptide largely prevented the retrovirus-induced reduction in B- and T-cell proliferation, and T-helper 1 (Th1) cytokines [interleukin-2 (IL-2) and interferon-gamma (IFN-gamma)] secretion. It also suppressed T-helper 2 (Th2) cytokines (IL-6 and IL-10) production, which was stimulated by retrovirus infection. These effects were accomplished using at least 100 micrograms of peptide per mouse and the most effective dose of peptide had to be given within 4 weeks after retrovirus infection. Immunization with doses above 100 micrograms/mouse as long as 4 weeks postinfection maintained natural killer (NK) cell activity during retrovirus infection. Reducing the dose of peptide or delaying it until the disease progressed towards early murine acquired immune deficiency syndrome (AIDS) allowed development of immune dysfunction. These studies provide data suggesting that immune dysfunction, induced by murine retrovirus infection, was largely prevented by TCR V beta CDR1 peptide injection.

Adjuvants, Immunologic↗

Neutropenia in patients infected with human immunodeficiency virus.

The possible mechanisms of neutropenia associated with both human immunodeficiency virus (HIV) infection and drug treatment in adults are examined, and the current and investigational strategies for managing neutropenia are reviewed. Neutropenia associated with HIV arises from diverse mechanisms, including cellular immune dysfunction, direct effects on progenitor cells, humoral immune dysfunction, and vitamin deficiencies. Drug-induced neutropenia may be related to direct cytotoxic effects, immunologic mediators, and the effects of vitamin depletion on the bone marrow. Bone marrow toxicity in patients receiving zidovudine appears to be more frequent in those patients with advanced disease, low CD4 cell counts, a pretreatment anemia, low serum vitamin B12 levels, and low or low normal serum folic acid levels. Patients with AIDS also are at increased risk for adverse events associated with folate antagonists and sulfonamides compared with other patient populations. Lithium therapy has improved neutrophil counts in patients receiving zidovudine; however, the toxicities associated with use of lithium, combined with the lower dosages of zidovudine now recommended, may obviate its use. The use of colony-stimulating factors appears promising for increasing the number and function of circulating neutrophils. Although concomitant use of interferon alfa and zidovudine may result in a strong synergistic anti-HIV effect, dose-limiting neutropenia has been reported in patients receiving the combination. There are currently no controlled data assessing the effectiveness of intravenous immune globulin in the treatment of HIV-related or drug-related neutropenia. In evaluating neutropenia, the clinician must attempt to discern whether the neutropenia is more likely related to disease state(s) or drug therapies. Potential management strategies include modulation of the disease state, discontinuation or dose reduction of the offending agent, or administration of exogenous immune enhancer.

Acyclovir↗

A biochemical analysis of people with chronic fatigue who have Irlen Syndrome: speculation concerning immune system dysfunction.

This study investigated the biological basis of visual processing disabilities in adults with Chronic Fatigue Syndrome. The study involved 61 adults with symptoms of Chronic Fatigue Syndrome who were screened for visual processing problems (Irlen Syndrome) and divided into two groups according to the severity of symptoms of Irlen Syndrome. Significant variations were identified in blood lipids and urine amino and organic acids of the two groups, which may be indicative of activation of the immune system due to some infective agent. It was suggested that metabolic profiling may help the development of more valid diagnostic categories and allow more investigation of immune system dysfunction as a possible causal factor in a range of learning and behaviour disorders.

Adult↗

[Kaposi's disease. Form with lymph node manifestation in a young African. Difficulty in the initial diagnosis and relation to dysimmune lymphadenitis].

The authors report a case of Kaposi's sarcoma in a 38-year-old Malian. Onset occurred one year after an episode of febrile polyadenopathy with histologic features suggestive of immune dysfunction lymphadenitis. Diagnosis of Kaposi's sarcoma was firmly established only following occurrence of secondary skin lesions. This case exemplifies the diagnostic problems raised by those forms of Kaposi's sarcoma which present as lymph node involvement. In the index case, the authors discuss the significance of the initial polyadenopathy, and speculate whether it was an initial stage of Kaposi's sarcoma or an immune dysfunction lymphadenitis preceding onset of the sarcoma. If the second hypothesis is correct, this case would be comparable to reports of Kaposi's sarcoma arising in hosts with immune dysfunction.

Adult↗

Immunologic parameters in chronic fatigue syndrome, major depression, and multiple sclerosis.

The purpose of this study was to evaluate the immune dysfunction hypothesis of chronic fatigue syndrome (CFS) by comparing immunologic data from patients with CFS with data from patients with other fatiguing illnesses--major depression and multiple sclerosis (MS)--and with data from healthy sedentary controls. The subjects were 65 healthy sedentary controls, 71 CFS patients (41 with no axis-I diagnosis), 23 patients with mild MS, and 21 patients with major depression. Blood was sampled and assayed for the following: (1) immunologic serologic variables--circulating immune complexes (i.e., Raji cell and C1q binding), immunoglobulins A, E, G, and M, and IgG subclasses; (2) cell surface activation markers--the proportion of CD4+ cells expressing CD45RA+ and CD45RO+ and the proportion of CD8+ cells expressing CD38+, CD11b-, HLA-DR+ and CD28+; and (3) natural killer (NK) total cell count as well as the proportion of lymphocytes expressing NK cell surface markers (i.e., CD3-/CD16+ and CD56+. Of the 18 variables studied, differences between CFS patients and controls were found only for IgG1 and IgG3. When CFS patients were stratified by the presence or absence of concurrent axis-I disease, it was the group with axis-I disorder that had the lowest IgG1 values-contrary to expectation. When data from patients with MS and major depression were also evaluated, the subclass deficiency was no longer significant. The one group to show evidence for immune activation (i.e., an elevated proportion of CD4+ cells expressing the CD45RA+ activation marker) was the group with mild MS. These data support neither immune dysfunction nor immune activation in CFS or in major depression, for the variables studied. The reductions in IgG subclasses may be an epiphenomenon of patient or control subject composition. In contrast, MS, even in the mild and early stages, as in the patients studied here, is associated with immune activation.

Adult↗

Necrotizing ulcerative periodontitis.

In patients with no known systemic disease or immune dysfunction, necrotizing periodontitis (NUP) appears to share many of the clinical and etiologic characteristics of necrotizing ulcerative gingivitis (NUG) except that patients with NUP demonstrate loss of clinical attachment and alveolar bone at affected sites. In these patients, NUP may be a sequela of a single or multiple episodes of NUG or may be the result of the occurrence of necrotizing disease at a previously periodontitis-affected site. The existence of immune dysfunction may predispose patients to NUG and NUP, especially when associated with an infection of microorganisms frequently associated with periodontal disease such as Treponema and Selenomonas species, Fuscobacterium nucleatum, Prevotella intermedia, and Porphyromonas gingivalis. The role of immune dysfunction is exemplified by the occasionally aggressive nature of necrotic forms of periodontal disease seen in patients with HIV infection or malnutrition, both of which may impact host defenses. Clinical studies of HIV-infected patients have shown that patients with NUP are 20.8 times more likely to have CD4+ cell counts below 200 cells/mm3. However, these same studies have demonstrated that most patients with CD4+ cell counts below 200 cells/mm do not have NUP, suggesting that other factors, in addition to immunocompromisation, are involved. Further studies are needed to define the complex interactions between the microbial, or viral, etiology of necrotic lesions and the immunocompromised host. It is, therefore, recommended that NUG and NUP be classified together under the grouping of necrotizing periodontal diseases based on their clinical characteristics.

Disease Progression↗

Murine complement-mediated immune clearance dysfunction is associated with the lymphoproliferative (lpr) gene.

Using a branched series model of immune clearance and an iterative curve fitting process, we have previously demonstrated abnormal in vivo clearance of opsonized erythrocytes in autoimmune MRL-lpr/lpr mice. This technique allows simultaneous evaluation of four rate constants governing both complement- and Fc-mediated clearance; i.e., complement-mediated sequestration (k1), C3b deactivation and release (k2), complement-dependent phagocytosis (k4), and Fc gamma-mediated sequestration and phagocytosis (k3). To evaluate genetic factors which may contribute to abnormal clearance in MRL-lpr/lpr mice, serial clearance studies were performed in congenic MRL-(+/+) mice, as well as in several mouse strains homozygous for the lymphoproliferative gene; i.e., BALB/c-lpr/lpr and C57BL/6-lpr/lpr mice. Rate data were obtained from mice 3 months through 12-18 months of age, and mean rate constant values compared to control BALB/c and/or C57BL/6 mice. Clearance of opsonized cells in MRL-lpr/lpr mice was characterized by both abnormal complement and Fc gamma receptor function with decreased complement-mediated sequestration, complement-dependent phagocytosis, and Fc gamma-mediated sequestration and phagocytosis. In contrast, abnormal clearance in congenic MRL-(+/+) mice was characterized by decreased Fc gamma-mediated sequestration and phagocytosis (P < 0.0001) only. Both complement-mediated sequestration and complement-dependent phagocytosis were significantly decreased in BALB/c-lpr/lpr and C57BL/6-lpr/lpr mice (P < 0.0001), with the pattern and magnitude of abnormal complement clearance kinetics similar to that occurring in MRL-lpr/lpr mice and contrasting with normal complement-mediated clearance in control BALB/c and C57BL/6 mice. Since decreased complement-mediated clearance was observed in three differing strains of mice homozygous for the lymphoproliferative gene, these data suggest that clearance of opsonized cells in mice is in part genetically determined, and that there may be a specific association between complement-mediated clearance dysfunction and the murine lymphoproliferative gene.

Animals↗

Effects of vaccination against different T cell receptors on maintenance of immune function during murine retrovirus infection.

Murine retrovirus infection causes an aberrant stimulation of several subsets of T helper 2 cells identified by their T cell receptors (TCR). C57BL/6 mice were treated with synthetic peptides based upon different human TCR V beta CDR1 sequences following experimental infection with the murine retrovirus. Previous studies established that retrovirally infected mice produced autoantibodies to certain of these peptides, and their administration after infection diminished many of the cytokine abnormalities induced by the virus. This study determined whether the complete 16-mer synthetic peptides modeling the V beta CDR1/FR3 were required, and whether admixture of autoantigenic peptides synergized immune preservation. Treatment with complete TCR pep beta 3 and pep V beta 5.2 peptide alone and combined largely prevented the retrovirus-induced reduction in B and T cell proliferation and Th1 cytokine secretion while suppressing excessive production of Th2 cytokines, which are stimulated by retrovirus infection. Treatment with overlapping short peptides corresponding to the N-terminal 11-mer and C-terminal 12-mer did not significantly prevent the immune dysfunction in retrovirus-infected mice. These data suggest that immune dysfunction and abnormal cytokine production, induced by murine retrovirus infection, were largely prevented by TCR V beta CDR1 peptides, and the complete CDR1 in association with the five residues from FR2 was required.

Amino Acid Sequence↗