Limb regeneration of the adult newt (Notophthalmus viridescens) in the absence of the spleen

Summary It has been suggested that the immune system might figure prominently in the regulation of forelimb regeneration. However, neither the nature of this influence nor the aspect(s) of regeneration influenced are clearly known. The determination of which components of the immune system are indispensable for regeneration would be a logical first step in attempting to address such questions. This investigation, therefore, examined the effects of removing the spleen, a major lymphoid organ in the newt, upon the progress of regeneration. Splenectomies performed concomitantly with or after forelimb amputation failed to alter the time course of regeneration. Splenectomies, but not sham-splenectomies, performed prior to amputation reduced the time required to achieve successive stages of regeneration under some, but not all conditions, i.e., when performed 10–20 days before amputation, during the late fall and winter. Up until 35 days after amputation, no gross morphological distortions were observed as a result of splenectomy. It was concluded that the spleen is not required for regeneration to occur.Portions of this work constitute part of the thesis submitted by M.E. Fini in partial fulfillment of the requirements for the M.S. degree in Biology at Boston College     

Immunocytochemical localization of conglutin γ and legumin-like globulin in developing and mature seeds ofLupinus albus L.

Summary The distribution of two seed proteins, namely conglutin and a legumin-like globulin, in developing and mature seeds ofLupinus albus L. has been examined by immunocytochemistry and the concomitant modifications of their constituent polypeptides followed by SDS-PAGE. Both proteins were found within vacuolar protein bodies in various tissues of the cotyledons, although with some differences in the distribution patterns. The legumin-like protein was found to be deposited within the large storage parenchyma cells of the cotyledons in a manner similar to that reported for other storage proteins; little or no immunolabelling was associated with the cotyledonary epidermal and vascular parenchyma cells. In contrast conglutin was present in all cell types.A precursor of the legumin-like protein accumulated transiently in the developing cotyledon, but was subsequently modified by proteolytic cleavage. The onset of such modification was concomitant with a transition in the predominant vacuolar forms within the storage parenchyma cells. No precursor molecules of conglutin have been detected in this study, thus indicating that this protein is deposited in the protein bodies in its mature form.Abbreviations LM light microscopy - EM electron microscopy - DAF days after flowering - SDS-PAGE sodium dodecyl sulphate polyacrylamide gel electrophoresis - GAR goat antirabbit antiserum     

Plasmodium berghei: a mouse model for the "sudden death" and "malarial lung" syndromes

A mouse model for the "sudden death" and "malarial lung" syndromes is described. Mice of the C3H/z strain succumb suddenly approximately 7 days after an infection with Plasmodium berghei becomes patent, at a time when parasitemia is still moderate (6 to 8%). Death could be shown to be due to anaphylactoid shock, probably induced by soluble immune complexes. Increased vascular permeability caused transudation and leakage of serum proteins into the interstitium and the alveoli. The lungs were found to be edematous, with a fine granular precipitate in the alveoli and adherent to the vascular walls. The precipitates reacted with antiglobulins G and M, and could be shown to also contain malaria antigens and C3/4. A dramatic drop in hematocrit was recorded several hours before death, indicating the sudden release of malaria antigens. The myocardium of animals that had died very suddenly showed a patchy loss of phosphorylase activity. This loss of activity was much more extensive, and sometimes almost total, when there had been an agonal period of several (1 to 3) hours before death. In these cases the irreversibility of the myocardial damage was also indicated by the loss of activity of the dehydrogenases, as well as by typical inflammatory reactions of granulocytic and histiocytic infiltrations. The hearts thus presented a typical picture of the acute and peracute shock syndromes. In acute shock cardiac insufficiency develops so suddenly that death ensues before irreversible damage has occurred, and cardiac insufficiency can only be demonstrated by the most sensitive of enzyme histochemical means. In the present case shock was induced by the anaphylactoid activity of immune complexes with the lung as target organ. The described syndrome appears analogous to human "malarial lung."     

Trichinella spiralis: selective intestinal immune deviation in the rat

In rats, infections with 100-2000 Trichinella spiralis muscle larvae lead to a prompt immunity that is expressed in parasite expulsion within 14 days. Rats infected with more than 2000 larvae display impaired immunity with rejection delayed by 50% (7 days) or more. Suppression is selective for expulsive immunity as the antifecundity response of rats is directly proportional to dose and is expressed sooner in heavily infected subjects. Suppression of intestinal expulsive immunity was suggested by the fact that, with low doses (2000 larvae or less), worm rejection was inhibited by cortisone, whereas cortisone inhibited antifecundity but had no discernable effect on worm rejection in high-dose infections. Evidence for local immune deviation as opposed to systemic immunosuppression was obtained in experiments using parabiotic rats. When one partner was infected with 6000 worms and the other with 200, the rat infected with 200 parasites showed earlier rejection than was seen in single controls infected with 200 worms. The prolonged survival of high-dose adults was not accompanied by a change in the site of worm residence in the gut. Immunological parameters such as serum antibody levels, the number of activated cells or specific anti-T. spiralis lymphocytes in thoracic duct lymph were all increased in a dose-dependent manner. These experiments therefore demonstrate a novel autoprotective mechanism by which adult T. spiralis selectively reduce the expression of expulsive immunity in the gut.     

Adaptive surface antigen variation in Mycoplasma bovis to the host immune response

Abstract The variability of predominant Mycoplasma bovis surface antigens in the presence of specific immune pressure was analyzed in an in vitro assay to determine if M. bovis could escape immune destruction. We have shown that serum antibodies from immunized or experimentally infected calves and monoclonal antibodies which specifically react with previously characterized or as yet undefined major M. bovis membrane surface proteins cause repression of expression or shortening of the target protein, or induce switching to expression of an antigenically distinct variant protein. We have further demonstrated that removal of the inducing antibody results in reversion to the original phenotype. These results suggest that the level of expression and the length of M. bovis surface antigens in the host is modulated by cognate antibodies. According to the surface antigenic variation systems, random selection of preexisting variants resistant to antibody-mediated inhibition or direct regulation of gene expression may be means by which this organism evades host immune defences.     

流行性出血热患者皮肤组织内病毒抗原及免疫复合物检测与意义

应用常规病理、免疫病理及超微病理技术,对３３例流行性出血热（ＥＨＦ）患者皮肤活检标本的病理变化及病毒抗原、免疫复合物进行观察,同时与血清病毒抗原、抗体及循环免疫复合物检出情况进行比较。在２３例ＥＨＦ患者皮肤微血管内皮细胞中检出病毒抗原,部分组织中可同时检出免疫球蛋白及Ｃ３,少数组织仅能检出病毒抗原或免疫球蛋白。配对血清小也可检出ＥＨＦ病毒抗原、抗体及循环免疫复合物。组织及血清免疫复合物形成与血清补体Ｃ３水平下降有关,组织内肥大细胞脱颗粒与血清ＩｇＥ水平升高相关,提示多种变态反应参与了流行性出血热的发病机制。     

Topography of the enteric nervous system in Peyer's patches of the porcine small intestine

The mechanisms of intercommunication between the immune and nervous systems are not fully understood. In the case of the intestine, the enteric nervous system is involved in the regulation of immune responses. It was therefore decided to employ immunohistochemical techniques to investigate the structural organization of the enteric nervous system in Peyer's patches of the porcine small intestine. Using antibodies against various nervous system-specific markers (protein gene product 9.5, neuron-specific enolase, neurofilament 200, S-100 protein and the glial fibrillary acidic protein), an intimate and specific structural association could be demonstrated between enteric nerves and the compartments of Peyer's patches: follicles, interfollicular regions and domes. Peyer's patches have a close topographical relationship to the two submucosal plexuses. Enteric nerves are located around the follicle in the interfollicular area — the so-called traffic area-and in the dome area, which plays an important role in the uptake and presentation of antigens.     

伤寒-鼠伤寒重组株Vi4072在小鼠中定居及血清学效果观察试验

将编码Vi抗原的基因克隆到减毒的鼠伤寒沙门氏菌中组建的基因重组株Vi4072,以3×10~8CFU一次口服感染Balb/C小鼠,4天后按7,14,21,28,35,42,49,56,63,70天的间隔收集分离小鼠的集合淋巴结,肝,脾.鉴别是否有本菌出现,并检测血清和小肠匀浆液中的vi抗体.结果表明,感染后49天仍可从脾中分离到该菌;70天仍可从血清和小肠匀浆液中测出vi抗体。     

Elevated serum α-fetoprotein level of nude mice bearing hepatoma cells by treatment with monoclonal antibodies to α-fetoprotein

This study was carried out to clarify the reason for elevation of serum α-fetoprotein (AFP) level of nude mice bearing hepatoma cells after treatment with monoclonal antibodies (MoAbs) to AFP. MoAbs to AFP showed no effect on the cumulative amounts of AFP secreted from human hepatoma cell line, HuH-7, in vitro. However, the treatment of nude mice bearing HuH-7N cells (HuH-7 xenograft) with MoAbs to AFP led to elevation of the serum AFP level in spite of the fact that the growth curve of HuH-7N cells was similar to that for PBS treatment. This apparent elevation of the serum AFP level is thought to be due to the slow elimination of AFP-MoAb immune complexes with little lattice structure from circulation, but not the enhancement of AFP secretion of HuH-7N cells. Thus, when using a MoAb alone or MoAb-drug conjugate, the serum AFP level should only be cautiously used as a tumor marker for evaluating the targeting immunotherapy.