Characterization of certain hepatocyte-proliferating and/or protective factors induced by the sensitization of freezing-thawing hepatic tissue

Although tumor cryosurgery would be expected to produce beneficial immunological effects from the enhancement of anti-tumor activity, under certain conditions the tumor may become enlarged and metastases promoted due to increased immunosuppressive activity and a high zone tolerance. In the present study, we examined whether hepatocyteproliferating factors were produced by the inoculation of freezing-thawing hepatic tissue (FTHT). Serum obtained from rats inoculated with FTHT increased DNA synthesis, according to measurement by [³H]thymidine incorporation in primary cultured rat hepatocytes. This increase was dependent on the serum concentration, with serum obtained on day 14 after the inoculation being the most potent for hepatocyte proliferation. The sensitized serum promoted DNA synthesis nearly as much as serum obtained from a 70% hepatectomized rat, but slightly less than 10ng/ml hepatocyte growth factor. The sensitized serum also protected hepatocytes from carbon tetrachloride (CCI₄)-induced hepatotoxicity. Optical density measured by the 3-(4,5-dimethyl-thiazole-2-yl)-2,5-diphenyl tetrozolium bromide (MTT) cytotoxicity assay was increased, and the release of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase in medium was decreased by treating hepatocytes damaged by CCI₄ with the sensitized serum. These results suggest that certain hepatocyte-proliferating and protective factors are induced in serum by the inoculation of freezing-thawing hepatic tissue, and that the sensitized serum may be useful in the treatment of liver failure.     

低温洗涤红细胞肺保护液对体外循环术后肺保护作用的研究

目的:探讨体外循环(cardiopulmonarybypass,CPB)术中采用低温洗涤红细胞肺保护液实施肺动脉灌注对肺的保护效果。方法:随机选取20例风湿性单纯二尖瓣病变合并中度肺动脉高压的患者,分为肺动脉灌注组和对照组(每组各10例)。灌注组在主动脉阻断后,经肺动脉根部间断灌注低温洗涤红细胞肺保护液,测定两组患者围术期的机械通气时间、肺血管阻力、白细胞比值(静脉血/动脉血)、肺循环血浆MDA含量。结果:体外循环术后灌注组机械通气时间显著低于对照组(P<0.05);各时点肺血管阻力、白细胞比值(静脉血/动脉血)、肺循环血浆MDA含量均显著低于对照组(P<0.01)。结论:低温洗涤红细胞肺保护液肺动脉灌注对体外循环术后肺损伤有明显的保护作用.     

Protective immunity to malaria: studies with cloned lines of rodent malaria in CBA/Ca mice. IV. The specificity of mechanisms resulting in crisis and resolution of the primary acute phase parasitaemia of. Plasmodium chabaudi chabaudi and P. yoelii yoelii

Low numbers of parasites from cloned lines of the rodent malaria parasites, Plasmodium chabaudi chabaudi AS and P. yoelii yoelii A, injected into CBA/Ca mice produce acute but usually self-limiting infections. During crisis, i.e. 1-2 days after peak parasitaemia, 'pre-immune' mice experiencing such 'background' infections were reinfected intravenously with homologous parasites or parasites of heterologous strains or species. P. c. chabaudi AS pre-immune mice controlled an AS challenge with essentially the same kinetics as the background infection. Reinfection of AS pre-immune mice with the heterologous (CB and IP-PCI) P. c. chabaudi strains or P. chabaudi adami DS had little effect on the initial growth of these parasites, although eventually the parasitaemia was controlled. In contrast, a partial inhibitory effect on the growth of P. vinckei lentum DS was evident. Challenge with the non-lethal (A) or lethal (YM) variants of P. y. yoelii resulted in an increase in both the growth and virulence of these parasites. P. y. yoelii A pre-immune mice controlled a homologous challenge, but were less effective at controlling the YM variant. In addition, they were unable to clear rapidly a P. c. chabaudi AS or P. v. lentum DS challenge. Both the multiplication and virulence of P. berghei ANKA were enhanced. These findings demonstrate that resolution of the primary acute parasitaemia in P. c. chabaudi AS- and P. y. yoelii A-infected mice is predominantly mediated by species- and strain-specific mechanisms.     

IL-5 production by allergen-stimulated T cells following grass pollen immunotherapy for seasonal allergic rhinitis

We have previously identified the hevein preprotein as a common allergen for latex allergic healthcare workers. The B cell epitopes in the hevein protein that are recognized by IgE of latex-allergic individuals have not been identified. In this study, we examined the hevein preprotein using epitope mapping. Overlapping synthetic peptides of 10 amino acids (two aa overlap) were synthesized on a derivatized cellulose membrane using Fmoc chemistry. The peptide spots were probed with pooled sera from 10 latex-allergic patients, and the IgE-reactive peptides identified with anti-IgE MoAbs. We identified six B cell epitopes within the full length hevein preprotein which bound IgE from latex-allergic patients. Two were located in the N-terminal 5-kD hevein domain and four were observed in the 14-kD C-domain. A broad epitope was located between the N-terminal amino acids 13–24. This epitope had nearly complete homology to wheat germ agglutinin (WGA). Immunological cross-reactivity to WGA was confirmed by Western blot analysis with purified WGA, and this reactivity could be inhibited by latex proteins or WGA. Of the five remaining epitopes, four had homologies to other proteins in the pathogenesis-related family of plant proteins (PR-4). The data demonstrate that hevein has multiple IgE epitopes. The significant homology of these epitopes to a broad family of plant defence proteins further explains the increased prevalence of food allergies in latex-allergic individuals.     

Induction of antibody responses to breast carcinoma associated mucins using synthetic peptide constructs as immunogens

A strategy for directing and enhancing B cell immune responses against synthetic peptide determinants has been developed in order to produce antibodies specifically against protein epitopes of clinical relevance. A peptide sequence based upon the MUC-1 mucin protein core was selected for this purpose since anti-MUC-1 antibodies have proven diagnostic application and therapeutic potential in human breast and ovarian cancer. Peptide constructs were synthesised co-linearly linking the immunodominant B cell determinant region, PDTRPAP, in the protein core of the MUC-1 mucin, to sequence 111 – 120 of influenza haemagglutinin A/X-31, a determinant recognised by T helper cells through association with MHC class II molecules. Induction of anti-MUC-1 antibodies to the B cell determinant region by immunisation with peptide was shown to be dependent upon both the presence and the position of the T cell determinant. In addition, haplotype mismatching with respect to the T cell determinant resulted in a significant lowering of the anti-MUC-1 antibody response in peptide construct immunised mice. These findings are relevant to the design of immunogens to produce antibodies against peptide epitopes of tumour associated proteins and glycoproteins.     

抗人甲状腺球蛋白单克隆抗体的制备及其对抗原决定簇特异性的研究

用杂交瘤技术建立三株分泌抗甲状腺球蛋白(TG)单克隆抗体的杂交瘤细胞株。所获三种单克隆抗体经兔抗小鼠IgG亚类、IgM及IgA血清鉴定表明,两种为IgG_1,一种为IgA;三种含单克隆抗体小鼠腹水的滴度(ELISA法)均为51200以上;以竞争性固相抗体结合试验测定它们对抗原决定簇的特异性差异,结果发现三种单克隆抗体的抗原结合部位是不同的,但对抗原的结合有一定的相互竞争抑制现象。     

The use of restricted spectral range red lenses for the diagnosis and relief of dazzlement of a rod monochromat

An infant rod monochromat was diagnosed and was then treated with the Younger PLS 550 lens. The comparison in use of PLS 550 and a neutral density lens confirmed the presence of cone dysfunction. The use of this lens takes advantage of the spectral shift in luminosity between rods and cones. Younger PLS 550 and PLS 530 tints are used for the relief of photophobia according to prevailing brightness. This paper discusses patient management with the use of these lenses and some characteristics of the vision of a rod monochromat.     

Protective genes expressed in endothelial cells of second hamster heart transplants to rats carrying an accommodated first graft

Abstract: Accommodation refers to survival of a xenograft despite the presence of anti-donor organ antibodies and complement. We have recently shown that accommodation of a hamster heart transplanted to a rat receiving short-term cobra venom factor (CVF) and continuing cyclosporine A (CyA) therapy is associated with i) the expression in the endothelial cells (EC) and smooth muscle cells of the graft of a number of "protective" genes, ii) a prominent intragraft Th2 cytokine profile, and iii) the relatively heavy deposition of IgG2c antibodies on the EC of the graft. In contrast, rejecting grafts do not express the protective genes, have a Th1 cytokine profile, and apparently have lesser amounts of IgG2c. These findings are consistent with host factors (Th2 cytokines and IgG2c) contributing to xenograft accommodation. To test whether these host factors may predispose to the development of accommodation, we placed a second hamster heart into each of 12 rats carrying a surviving first heart; recipients were, at the time, receiving only CyA. Whereas first grafts transplanted to rats receiving only CyA survive for 3 to 4 days, 11 out of 12 second transplants survived more than 20 days, and the other survived for 7 days. Nine of the twelve were not rejected: of these, four were removed between day 35 and 132 for study, and the remainder are still beating at 35 to 52 days. The surviving second hearts we studied had accommodated in that the picture on immunopathology was the same as for surviving first hearts. We suggest that the Th2 cytokines and perhaps the IgG2c response are factors in allowing prolonged survival of the second grafts and, further, that these factors contribute to the expression in the EC and smooth muscle cells of the surviving second hearts of the protective genes.     

HLA-A9 antibodies and epitopes

Fifty pregnancy alloantisera directed towards HLA-A23 and/or A24 antigens were investigated serologically in titration studies against the three sequenced HLA-A9 specificities, A23 (A*2301), A24 (A*2402) and A2403 (A*2403). The reaction patterns of the antisera fell into five categories which allowed the three HLA-A9 specificities to be easily differentiated. Based on the various titre cytotoxicity scores of the antisera five possible antibody specificities were defined: anti-A23; -A24; -A23/24; -A24/2403 and anti-A23/24/2403. One antiserum crossreacted with HLA-A1 and A24. Inspection of the amino acid sequences of 136 HLA-A, B and C molecules allowed the prediction of five unique epitopes corresponding to these antibody specificities, a possible epitope unique to A2403 and confirmation of a likely epitope shared by A1 and A24. These, together with the previously suggested epitopes HLA-A9/ A2/A28 and A1/A23/A24 together with the presence of Bw4 on the three HLA-A9 antigens suggests that the HLA-A9 family of antigens is characterized by a minimum of nine serologically definable epitopes.     

Induction and expression of protective T cells during Mycobacterium avium infections in mice.

Mycobacterium avium is an opportunistic pathogen that infects individuals suffering from chronic lung disease or immunocompromised patients such as AIDS patients. Here we show that a highly virulent isolate of M. avium proliferated as extensively in T cell deficient as in immunocompetent mice. T cell deficient mice allowed a progressive growth of a less virulent AIDS-derived isolate of M. avium while immunocompetent mice arrested the growth of this isolate. Adoptive transfer of T cell enriched spleen cells between congenic strains of mice differing at the Bcg/Ity/Lsh locus showed that only naturally resistant BALB/c.Bcgr (C.D2) mice infected with the highly virulent strain of M. avium or the naturally susceptible BALB/c mice infected with the lower virulence isolate developed protective T cells and that these cells only mediated protection when transferred to naturally susceptible, but not to naturally resistant, mice. Both strains of M. avium proliferated in bone marrow-derived macrophages cultured in vitro and they were both susceptible to the bacteriostatic effects induced in the macrophages by crude lymphokines produced by concanavalin A-stimulated spleen cells.