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1.
Effect of carrier priming on antibody avidity in the in vivo and in vitro immune response.
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The effect of carrier priming on antibody avidity was investigated under several experimental conditions. Basically, mice were carrier primed with HRBC (horse red blood cells) prior to immunization with TNP (2,4,6-trinitrophenyl) conjugated to HRBC. Immunization was performed either in vivo or in spleen cell culture, and avidity of anti-TNP antibodies was estimated from inhibition of direct PFC (plaque-forming cells) by free TNP-BSA (-bovine serum albumin).The data indicate the appropriate conditions under which carrier priming can enhance antibody avidity. The carrier effect is maximized by priming the animals with 104-105 HRBC 3-7 days before immunization with a low dose of TNP-HRBC. Hyper-immunization by repeated injections of a high dose of the conjugate does not modify the carrier effect on avidity but it delays the fall of avidity in both carrier primed and unprimed animals. These results are interpreted in terms of T- and B-cell co-operation within the framework of the maturation theory of antibody affinity.Carrier priming was also found to increase the number of direct PFC of the IgM and, mostly, of the non-IgM classes, a finding in agreement with the notion that T cells can help IgM production and the shift to IgG. 相似文献
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Drug-induced lupus erythematosus 总被引:1,自引:0,他引:1
Drug-induced lupus is a syndrome which share symptoms and laboratory characteristics with idiopathic systemic lupus erythematosus (SLE). The terms drug-induced lupus (DIL) and drug-induced lupus erythematosus (DILE) are preferred, but other ones are also used-drug-related lupus, lupus-like syndrome and lupus erythematosus medicamentosus. The first case of DILE was reported in 1945 and associated with sulfadiazine. In 1953, it was reported that DILE was related to the use of hydralazine. More than 80 drugs have been associated with DILE. The average age of patients with DILE is nearly twice that of patients with idiopathic SLE. Approximately half the patients with drug-induced SLE are women, compared with 90% of patients with idiopathic SLE. Similarly to idiopathic lupus, DILE can be divided into systemic, sub-acute cutaneous and chronic cutaneous lupus. The syndrome is characterised by arthralgia, myalgia, pleurisy, rash and fever in association with antinuclear antibodies in the serum. The clinical and laboratory manifestations of drug-induced SLE are similar to those of idiopathic SLE, but central nervous system and renal involvement are rare in DILE. Recognition of DILE is important because it usually reverts within a few weeks after stopping the drug. This review discusses the general issues in DILE, such as pathogenic mechanisms, clinical forms and diagnostic criteria, and provides more detailed information for some of the most recent implicated drugs: minocycline, statins, anti-TNF-alpha agents. 相似文献
3.
Frasca D Barattini P Tocchi G Guidi F Scarpaci S Guidi L Bartoloni C Errani A Costanzo M Doria G 《Mechanisms of ageing and development》2000,121(1-3):5-19
We have investigated the effects of an interleukin (IL)-6-type cytokine on the DNA-binding activity of ku and on unscheduled DNA repair in X-ray-treated peripheral blood mononuclear cells (PBMC) from human subjects of different ages. The cytokine used, called K-7/D-6, is an IL-6 variant with increased in vivo and in vitro biological activity compared to the wild type molecule. Ku is the DNA-binding component of the DNA-dependent protein kinase (DNA-PK). It binds the ends of various types of DNA discontinuity and is involved in the repair of DNA breaks caused by V(D)J recombination, isotype switching, physiological oxidation reactions, ionizing radiation and some chemotherapeutic drugs. The ku-dependent repair process, called non-homologous end joining, is the main DNA double strand break repair mechanism in irradiated mammalian cells. Results show that K-7/D-6 significantly increases DNA-binding activity of ku in irradiated PBMC from young but not from elderly subjects. However, K-7/D-6 is able to induce unscheduled DNA repair in irradiated PBMC from both young and elderly subjects. These effects of K-7/D-6 are relevant to the mechanisms of the cellular response to DNA damage. 相似文献
4.
W Barcellini M O Borghi C Sguotti R Palmieri D Frasca P L Meroni G Doria C Zanussi 《Clinical immunology and immunopathology》1988,47(2):142-151
We studied a group of healthy elderly subjects (satisfying the SENIEUR Protocol admission criteria), chosen as a model of age-associated immune deficiency on the basis of their reduced skin reactivity to recall antigens. Results show that aged subjects, taken as a whole, display impaired T-cell functions: reduced blastogenetic responses to mitogens, IL-2 production, responsiveness to exogenous IL-2, and percentage of Tac positive blasts. However, the age-associated immune defect shows a wide range of impairment, even in a relatively homogeneous group of anergic/hypoergic subjects. In fact, a considerable proportion of our elderly subjects displays responses comparable with those of adult controls. These observations suggest that (a) immune deficiency is not a characteristic of aging per se; (b) cutaneous delayed hypersensitivity is not a criterion sensitive enough to identify people with age-associated immune deficit; and (c) more than one test is required to evaluate T-cell impairment in aging. 相似文献
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The negative role exerted by cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) in the regulation of T-cell activity, as induced by T-cell receptor (TCR)/CD3 and CD28 costimulation, has been widely described. In the present work we investigated the role of CTLA-4 in the control of cell activation, as induced by costimulation of the adhesion molecule lymphocyte function-associated antigen-1 (LFA-1) in murine CD4+ T cells. Results show that CTLA-4 engagement inhibits interleukin-2 (IL-2) production, not only when induced by CD3/CD28 costimulation, but also when CD4+ T cells are costimulated by anti-CD3 and anti-LFA-1 monoclonal antibodies (mAbs). LFA-1 has been described to induce Ca2+ mobilization also in the absence of TCR engagement. Moreover, we found that CTLA-4 engagement negatively affects Ca2+ mobilization and NF-AT activation, as induced by LFA-1 engagement alone. PLCgamma1 phosphorylation was also dampened within minutes after CTLA-4 engagement. Altogether these data indicate that through the control of signals induced by different receptors, CTLA-4 could be a global attenuator of T-cell activation. 相似文献
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Efficacy of intracytoplasmic sperm injection using intentionally cryopreserved epididymal spermatozoa 总被引:1,自引:6,他引:1
Oates Robert D.; Lobel Susan M.; Harris Doria H.; Pang Samuel; Burgess Colleen M.; Carson Ronald S. 《Human reproduction (Oxford, England)》1996,11(1):133-138
Microsurgical epididymal sperm aspiration was a great advancein the therapy of patients with non-recon-structable, obstructiveazoospermia, most notably congenital bilateral absence of thevas deferens. Using conventional in-vitro fertilization, pregnancieswere rarely achieved because the rate of oocyte fertilizationwas extremely poor. However, the use of retrieved spermatozoain conjunction with intracytoplasmic sperm injection (ICSI)has dramatically increased the likelihood of embryo formation.Typically, sperm and oocyte harvesting are performed simultaneously.We have investigated whether frozen-thawed spermatozoa workas well as fresh spermatozoa. When we had concluded from ourown population of patients (groups I and II) that they did,we adopted a policy of aspirating spermatozoa, primarily cryopreservingthem and using them for ICSI at a later date. We found the fertilizationrates of this latter cohort of patients (group III) to be excellent(37% per oocyte), and the ongoing pregnancy rate is quite satisfactory(40 % per couple, 29% per cycle). We offer this approach asan alternative to the traditional scheme because it markedlyeases the burden of partner scheduling on both the couple andthe clinicians involved. In addition, assurance of the availabilityof male partner spermatozoa can be attained prior to beginningovulation induction. 相似文献