Extraneural prion neuroinvasion without lymphoreticular system infection

While prion infection of the lymphoreticular system (LRS) is necessary for neuroinvasion in many prion diseases, in bovine spongiform encephalopathy and atypical cases of sheep scrapie there is evidence to challenge that LRS infection is required for neuroinvasion. Here we investigated the role of prion infection of LRS tissues in neuroinvasion following extraneural inoculation with the HY and DY strains of the transmissible mink encephalopathy (TME) agent. DY TME agent infectivity was not detected in spleen or lymph nodes following intraperitoneal inoculation and clinical disease was not observed following inoculation into the peritoneum or lymph nodes, or after oral ingestion. In contrast, inoculation of the HY TME agent by each of these peripheral routes resulted in replication in the spleen and lymph nodes and induced clinical disease. To clarify the role of the LRS in neuroinvasion, the HY and DY TME agents were also inoculated into the tongue because it is densely innervated and lesions on the tongue, which are common in ruminants, increase the susceptibility of hamsters to experimental prion disease. Following intratongue inoculation, the DY TME agent caused prion disease and was detected in both the tongue and brainstem nuclei that innervate the tongue, but the prion protein PrP(Sc) was not detected in the spleen or lymph nodes. These findings indicate that the DY TME agent can spread from the tongue to the brain along cranial nerves and neuroinvasion does not require agent replication in the LRS. These studies provide support for prion neuroinvasion from highly innervated peripheral tissues in the absence of LRS infection in natural prion diseases of livestock.     

Spread of herpes simplex virus in lymph nodes after experimental infection of mice

Herpes simplex virus was frequently isolated from ipsilateral popliteal lymph nodes after percutaneous inoculation of the dorsal face of the footpad, and from ipsi- and contralateral submandibular lymph nodes after percutaneous inoculation of the cheek or the orofacial area of mice. Virus was detected only on very rare occasion in nondraining lymph nodes (inguinal or axillary) or in contralateral popliteal lymph nodes, but was frequently isolated in contralateral lumbar lymph nodes after footpad inoculation. The presence of virus in lymph nodes paralleled or followed the invasion of ipsilateral sensory ganglia and was associated with dissemination of virus in contralateral sensory ganglia after unilateral inoculation. In older mice virus was detected only occasionally in lymph nodes and dissemination of virus in contralateral sensory ganglia was generally not observed. The results suggest that lymphatic spread may contribute to dissemination of virus in contralateral sensory ganglia after unilateral inoculation of mice.     

Systemic administration of Corynebacterium parvum during sensitization to tumor alloantigen-modified response to rechallenge

Summary Intravenous administration of Corynebacterium parvum (C. parvum) to mice during a primary immune response against tumor alloantigens impairs their ability to generate memory cell-mediated cytotoxicity (CMC) in response to an intraperitoneal rechallenge with the same tumor alloantigens. Decreased CMC was observed in spleen and mesenteric lymph nodes, whereas CMC of lymphoid populations from the peritoneal cavity was merely delayed, reaching comparable levels to those found in control animals by day 5. Serum levels of cytotoxic antibody were unaffected, indicating that C. parvum administered during a primary immune response has selective effects on the cytotoxic memory response.     

Changes in the anatomic structures and cellular composition of lymph nodes after prenatal exposure to oleandomycin

Tracheobronchial and mesenteric lymph nodes have been investigated in 120 embryos, fetuses and newborn (5-, 14-, 30-day-old) rats by means of anatomical, histological and electron microscopical methods. Prenatal influence of oleandomycin phosphate on development of lymph nodes has been analysed. Effect of the drug on the mother--fetus system produces certain reactive changes in the anatomical structures responsible for the barrier-filtration and drainage functions of the lymph nodes. The immunocytopoietic function is inhibited, as demonstrates certain decrease of lymphatic line cells.     

Morphofunctional characteristics of the myocardium and regional lymph nodes of the heart in experimental myocardial ischemia under the effect of radon water on the body

A positive effect of radon baths (health resort "Belokurikha") has been stated on the course of restorative processes in the myocardium and regional lymph nodes of the heart at ischemic disease. An enhanced drainage activity of the lymph nodes revealed facilitates to a quick outflow of toxic lymph from the ischemic zone and, accordingly, to its biological treatment in the lymph nodes and contributes to a more complete restoration of the structure in the ischemia-damaged area of the myocardium.     

Route of antigen administration for tolerance production

Tolerance production is readily induced by inoculation of heterologous serum proteins in mice. The intravenous and intraperitoneal route are generally preferred because they allow rapid antigen equilibrium in the intra and extravascular spaces of the host. This report shows that the administration of particle-free antigen in the foot pad produces a greater number of tolerant animals at all concentrations used. The active participation of regional lymph nodes in tolerance production is postulated.     

Peptides of myelin basic protein are encephalitogenic in rats without the aid of emulsions.

Immunization with peptides is usually done with the aid of Freund's adjuvant. Using peptides derived from myelin basic protein, we show that aqueous solutions can be antigenic (encephalitogenic in this instance) in Lewis rats. The first procedure involved multiple doses of aqueous peptide, increased absorption into the lymphatic system from the peritoneal cavity in the postinflammatory state, and the use of pertussis vaccine. Three different peptides containing the major encephalitogenic site were active in this system, with the activity somewhat proportional to the size of the fragment. The second procedure, the direct delivery of peptide to lymph nodes by percutaneous inoculation, was equally successful and did not require the use of pertussis vaccine.     

Extrathymic rearrangement of αβT-lymphocyte antigen receptor genes during pregnancy

The existence of alphabetaT-lymphocyte differentiation processes have been demonstrated in mouse peripheral lymphoid organs during pregnancy. Study of pregnant Swiss mice has shown that the development of the second half of gestation is accompanied by expression of RAG-1 recombinase mRNA and unrearranged TCR alpha-chain (pre-TCRalpha) preferentially in T-lymphocytes of lymph nodes involved in uterine drainage (para-aortal lymph nodes), and to a lesser extent in other lymph nodes (mainly from axillary lymph nodes). The data suggest that during pregnancy the differentiation of alphabetaT lymphocytes may occur not only in central (thymus) but also in peripheral lymphoid organs.     

Leishmania braziliensis isolates differing at the genome level display distinctive features in BALB/c mice

Leishmania braziliensis is the species responsible for the majority of cases of human cutaneous leishmaniasis in Brazil. In the present study, L. braziliensis isolates from two different geographic areas in Brazil were studied by RAPD, using arbitrary primers. We also evaluated other biological features of these two isolates. We compared (a) the clinical features they initiate or not once delivered subcutaneously as stationary-phase promastigotes in the footpad of BALB/c mice; (b) the parasite load in both the footpad and the draining lymph node; (c) the cytokines present in the supernatant of cultures of the cell suspensions from the draining lymph nodes; and (d) the cell types present at the site of parasite delivery. The results show that the L. braziliensis strain from Ceará (H3227) is genotypically different from the L. braziliensis strain from Bahia (BA788). H3227-parasitized mice developed detectable lesions, whereas BA788-parasitized mice did not. Fifteen days post parasite inoculation there was an increase in the numbers of macrophages and lymphocytes in the footpads, whatever the parasite inoculum. Parasite load at the inoculation site--namely the footpad--did not differ significantly; in draining lymph nodes, however, it increased over the period under study. Early after parasite inoculation, the cells recovered from the draining lymph nodes of BA788-parasitized mice produced higher levels of IFN-gamma, a feature coupled to a higher number of NK cells. Later, after the parasite inoculation, there was an increased content of IL-12p70 and IL-10 in the supernatant of cells recovered from the lymph nodes of H3227-parasitized mice. This comparative analysis points out that L. braziliensis isolates differing in their genomic profiles do establish different parasitic processes in BALB/c mice.     

Immunosuppressive role of the liver in the graft versus host reaction]

The ability of the liver to reduce the intensity of the graft versus host (GVH) reaction has been investigated in F1 hybrid rats implanted with parental lymph nodes. Intrahepatic and intrarenal tissue implantations were compared using classical GVH criteria. The intrahepatic implantation of lymph nodes suppress the mortality observed after intrarenal implantation. The results confirm the interest of portal drainage in organ transplantation and suggest a new site of implantation for lymphoid cells.     

YAP蛋白核过表达与卵巢癌腹膜及淋巴结转移的相关性分析

目的:探讨Yes相关蛋白(YAP)与卵巢癌腹膜及淋巴结转移的相关性。方法:选择148例原发性卵巢癌和30例正常卵巢石蜡切片标本,采用Western blot、免疫组化分析YAP蛋白在正常卵巢组织、非转移性卵巢癌组织及转移性卵巢癌组织中的表达,分析YAP蛋白在卵巢癌组织中的表达与临床病理特征的关系,并应用单因素及多因素logistics分析卵巢癌腹膜和淋巴结转移的独立危险因素。结果:YAP蛋白在正常卵巢组织、非转移性卵巢癌组织及转移性卵巢癌组织中的表达量依次增高,两两比较差异均有统计学差异(P0.05)。YAP蛋白核过表达与组织学分化、残余病灶、复发、腹膜转移以及淋巴结转移均显著相关(P0.05)。YAP蛋白核过表达是独立的影响卵巢癌腹膜(OR:5.443;95%CI:2.287-12.950;P0.001)和淋巴结转移(OR:4.477;95%CI:2.059-9.735;P0.001)的独立危险因素。结论:YAP基因核过表达与卵巢癌腹膜转移及淋巴结转移密切相关,有可能作为临床上预测卵巢癌腹膜及淋巴结转移的新的分子标记物。     

Cell-mediated DNA transport between distant inflammatory sites following intradermal DNA immunization in the presence of adjuvant

After intradermal genetic immunization, naked DNA is transported from the site of injection to regional lymph nodes. Little is known on how inflammation influences this process and whether DNA is transported beyond local lymph nodes. In the experiments herein reported, we injected naked DNA in the presence of adjuvant to address questions related to 1) the fate of naked DNA in the presence of inflammation; 2) the generation of immune responses to the encoded protein during inflammation; and, more in general, 3) the fate of ingested molecules beyond regional lymph nodes during inflammation. Two sites of inflammation were induced in vivo in mice. Naked DNA was injected in the nape together with adjuvant, and adjuvant only was injected at a distant peritoneal site. Injected DNA, uptaken at the primary dermal site of inflammation, was transported beyond regional lymph nodes to distant organs such as the spleen and to the distant peritoneal site of inflammation. This transport, mediated by CD11b+ cells, was cumulative during chronic inflammation. These results indicate a novel route of transport of DNA beyond regional lymph nodes and may have specific implications for DNA-based immune modulation.     

Lymphatic drainage of calf melanoma skipping the superficial groin

BACKGROUND: Metastases of melanoma often follow predictable patterns of lymphatic drainage. However, some cases demonstrate first-echelon drainage to an unexpected basin. We describe a patient with drainage from melanoma on the calf to a sentinel lymph node in the iliac basin. METHODS AND RESULTS: Biopsy of the sentinel lymph node was guided by preoperative lymphoscintigraphy and intraoperative use of a gamma probe and blue dye. The node excised from the iliac basin showed evidence of metastasis. CONCLUSION: The failure to detect aberrant sentinel lymph nodes and bypassed basins may lead to improper assessment of disease stage and deficient patient management.     

Studies on immune responses to larval cestodes in mice: a simple mechanism of non-specific immunosuppression in Mesocestoides corti-infected mice

After intraperitoneal (i.p.) injection of sheep erythrocytes (SRBC) or dinitrophenylated Ficoll (DNP-Ficoll), mice infected with the larval cestode, Mesocestoides corti, contain at least 20x fewer antibody-secreting cells (PFC) in their spleens (or spleens plus lymph nodes) than uninfected mice. By contrast, intravenous injection of antigen leads to normal PFC responses. Results of studies on the fate of labelled syngeneic erythrocytes and foreign proteins suggest that i.p. injected materials are retained in the inflamed peritoneal cavity. Sequestration of antigen, and its subsequent local destruction, presumably accounts for the markedly suppressed systemic immune responses induced by i.p. injected antigens in M. corti-infected mice.     

Cellular Responses and Tissue Depots for Nanoformulated Antiretroviral Therapy

Long-acting nanoformulated antiretroviral therapy (nanoART) induces a range of innate immune migratory, phagocytic and secretory cell functions that perpetuate drug depots. While recycling endosomes serve as the macrophage subcellular depots, little is known of the dynamics of nanoART-cell interactions. To this end, we assessed temporal leukocyte responses, drug uptake and distribution following both intraperitoneal and intramuscular injection of nanoformulated atazanavir (nanoATV). Local inflammatory responses heralded drug distribution to peritoneal cell populations, regional lymph nodes, spleen and liver. This proceeded for three days in male Balb/c mice. NanoATV-induced changes in myeloid populations were assessed by fluorescence-activated cell sorting (FACS) with CD45, CD3, CD11b, F4/80, and GR-1 antibodies. The localization of nanoATV within leukocyte cell subsets was determined by confocal microscopy. Combined FACS and ultra-performance liquid chromatography tandem mass-spectrometry assays determined nanoATV carriages by cell-based vehicles. A robust granulocyte, but not peritoneal macrophage nanoATV response paralleled zymosan A treatment. ATV levels were highest at sites of injection in peritoneal or muscle macrophages, dependent on the injection site. The spleen and liver served as nanoATV tissue depots while drug levels in lymph nodes were higher than those recorded in plasma. Dual polymer and cell labeling demonstrated a nearly exclusive drug reservoir in macrophages within the liver and spleen. Overall, nanoART induces innate immune responses coincident with rapid tissue macrophage distribution. Taken together, these works provide avenues for therapeutic development designed towards chemical eradication of human immunodeficiency viral infection.     

Early detection of Leishmania (Leishmania) chagasi in draining lymph node after subcutaneous inoculation in hamster

To study the route of migration of Leishmania (Leishmania) chagasi to the viscera from the subcutaneous inoculation site, ultrastructural studies were carried out. These studies on popliteal draining lymph nodes of hamsters inoculated with 10⁷ promastigotes of Leishmania (Leishmania) chagasi in the hind footpad were carried out. Parasites were detected in lymph nodes just 2 h after inoculation. Parasites were either preserved or degenerated in macrophages. In 24 h signs of binary division of the parasites were found in macrophages. This fact suggests that the parasites migrate from skin to the lymph node early in the infection within phagocytes and proliferate in lymph nodes before dissemination to the viscera.     

Hapten-Specific T Cell Response to Azobenzenearsonate-N-Acetyl-L-Tyrosine (ABA-tyr) in Lewis Rats: II. Induction and Suppression of ABA-Specific Helper Cell Activity for Antibody Production

Immunization of Lewis rats with azobenzenearsonate-N-acetyl-l-tyrosine (ABA-tyr) in complete Freund's adjuvant (CFA), produces a hapten-specific helper T cell response measured by an increase in plaque forming cells (PFC) against a different hapten. The response seen is primarily direct (IgM) PFC unless B cells are primed by injection of trinitrophenylated keyhole limpet hemocyanin (TNP-KLH) prior to immunization with ABA-tyr. The response requires both ABA and TNP to be on the same carrier molecule which can be as diverse as bovine serum albumin (BSA), poly l-glutamine-lysine-tyrosine (l-GLT); however, a d-amino acid polypeptide does not work. The in vitro demonstration of such help was successful only with peritoneal exudate lymphocytes, not spleen or lymph node cells. Repeated pretreatment of rats by intraperitoneal injection of ABA-tyr in incomplete Freund's adjuvant (IFA) induced an unresponsiveness for helper activity to subsequent immunization with the same antigen in CFA. Passive transfer of lymphoid cells from spleens and lymph nodes from rats pretreated with ABA-tyr in IFA followed by boosting with ABA-tyr in CFA induced unresponsiveness to subsequent induction of hapten-specific help.     

Inflammatory and Phagocytic Response to Experimental Campylobacter jejuni Infection in Mice

After intraperitoneal inoculation with Campylobacter jejuni BALB/c, Swiss and DBA mice show a peritoneal inflammatory response of different intensity. Only BALB/c mice have a strong peritoneal response. Simultaneous intraperitoneal inoculation of C. jejuni plus FeCl₃ increase both inflammatory response and phagocytic activity in Swiss mice, without production of diarrhea. Some thermostable compounds of C. jejuni have a very strong chemotactic activity against peritoneal cells of mice, whereas a diffusible, thermolabile and glutaraldehyde-resistant factor has an inhibitory effect over murine peritoneal cell phagocytosis. Bactericidal activity of peritoneal cells increased after in vitro re-challenge with C. jejuni. Bacteremia is present in all the mice strains tested, but the clearance is quick in DBA and slow in BALB/c and Swiss mice. These experiments confirm that in mice, peritoneal non-specific mechanisms of defense, such as macrophages, play an important role in order to control C. jejuni infection.     

Measles virus infection of SLAM (CD150) knockin mice reproduces tropism and immunosuppression in human infection

The human signaling lymphocyte activation molecule (SLAM, also called CD150), a regulator of antigen-driven T-cell responses and macrophage functions, acts as a cellular receptor for measles virus (MV), and its V domain is necessary and sufficient for receptor function. We report here the generation of SLAM knockin mice in which the V domain of mouse SLAM was replaced by that of human SLAM. The chimeric SLAM had an expected distribution and normal function in the knockin mice. Splenocytes from the SLAM knockin mice permitted the in vitro growth of a virulent MV strain but not that of the Edmonston vaccine strain. Unlike in vitro infection, MV could grow only in SLAM knockin mice that also lacked the type I interferon receptor (IFNAR). After intraperitoneal or intranasal inoculation, MV was detected in the spleen and lymph nodes throughout the body but not in the thymus. Notably, the virus appeared first in the mediastinal lymph node after intranasal inoculation. Splenocytes from MV-infected IFNAR(-/-) SLAM knockin mice showed suppression of proliferative responses to concanavalin A. Thus, MV infection of SLAM knockin mice reproduces lymphotropism and immunosuppression in human infection, serving as a useful small animal model for measles.