Immunological diagnosis in viral infections of the central nervous system: course of antibody titres against homo- and heterologous viruses

In clinical cases suspected for viral encephalitis or meningoencephalitis, the estimation of virus-specific antibodies especially in liquor requires high sensitivity as well as specificity. With enzyme immunoassays the sensitivity in detecting antibodies has increased compared to e.g., complement fixation tests. This report concerns the determination of virus-specific antibodies with a commercial enzyme-linked immunosorbent assay (ELISA) in paired liquor/serum samples of four patients with encephalitis or meningoencephalitis. Up to six virus-specific antibodies of the IgG and IgM classes have been determined [herpes simplex virus (HSV), varicella-zoster virus (VZV), cytomegalo virus, mumps virus, measles virus, and rubella virus]. Additionally, serum samples from several patients suffering, or recovered from, diseases caused by HSV and VZV without CNS involvement have been included as controls. The results showed that besides the virus-specific antibody development (IgG and IgM) against the leading virus, i.e., principally concerned in the disease manifestation assumed to be primarily causing the disease, virus-specific antibodies of the IgG and IgM class against a heterologous virus (e.g., VZV) could also be measured with substantial titers. Cross-reacting antibodies to both HSV and VZV with the ELISA only appeared and were present in cases where the infection mainly affected the CNS: no such immunological cross-reactivity was observed in serum of individuals in clinically silent stages of both HSV and VZV infections. The same situation with no measurable cross-reacting antibodies was found in cases of acute HSV or VZV diseases where the CNS was not involved. These findings have been discussed with respect to the findings of common antigens, especially between HSV and VZV, and with respect to an unspecific stimulation of immunocompetent cells.Abbreviations and Definitions CSF Cerebrospinal fluid - ELISA enzyme-linked immunosorbent assay - CF-test complement fixation test - NT neutralization test - IFT immunofluorescence test - vIgG virus-specific IgG-antibody - vIgM virus-specific IgM-antibody - HSV herpes simplex virus - VZV varicella zoster virus - EEG electro-encephalogram - CCT cranial computer tomogram MEM, minim essential medium     

Comparison of the properties of five pox virus strains isolated from monkeys

Summary Five strains of monkey pox viruses were compared with respect to their cultural characteristics in primary and continuous cell cultures and the lesions developed in embryonated eggs and in rabbit skin as well as to their hemagglutinating activity.Four strains (Copenhagen 65-31 65-32 and 7-61) appeared to be similar in their properties. The cytopathogenic effect (CPE) was identical to that induced by vaccinia virus. There was no detectable virus multiplication in an pig kidney cell line (PEK). All four strains produced small, white, compact, hemorrhagic pock-like lesions on the chorioallantoic membrane.The strain 64–7275, isolated from healthy monkeys kidneys, had all properties of variola virus. It multiplied in the PEK cell line with a CPE. The lesions on the CAM were more compact without hemorrhage. In rabbit skin no detectable reaction occurred after infection with this strain.     

Investigation of the “valency” of antibodies by means of azoproteins

Summary The valency of antibodies was studied by the method of exhaustion of antisera against mono-and diazoproteins, and subsequent cross reactions both with the antibodies left over in the supernatant fluid of the serum and with the precipitating and nonprecipitating antibodies isolated from the precipitate.It was proved that the antibodies interact with the antigens as multivalent compounds.The valency determined with regard to the azoproteins is dependent upon the number of groups introduced.Thus, bivalent antibodies correspond to monoazoproteins and trivalent ones to diazoproteins.The valency of antibodies is, evidently, determined by the structural similarity of the heterologous and the immunizing antigens as well as by the less complete specific conformity between the individual structural peculiarities of the antigen and its antibody.From the Tashkent Pharmaceutical Institute (Director-Docent M. A. Azizov)Presented by Active Member AMN SSSR N. N. Zhukov-Verezhnikov     

Stimulation of human monocytes by anti-CD3 monoclonal antibody: Induction of inflammatory mediator release via immobilization of Fc receptor by adsorbed immunoglobulin and T-lymphocytes

Human monocytes released superoxide anion, prostaglandin E₂, leukotriene B₄, IL-1, and TNF when exposed to plastic surfaces coated with murine anti-CD3 monoclonal antibody, OKT 3. Stimulation of mediator release by OKT 3 was dependent on the amount of antibody immobilized onto wells of plastic tissue culture plates. Soluble antibody or antibody adsorbed to monocytes and reacted with an aggregating (cross-linking) second antibody failed to induce mediator release. Monocytes armed with OKT 3 formed rosettes with T cells in a fashion indistinguishable from that seen between monocytes and T cells sensitized with OKT 3. Monocytes with adsorbed OKT 3 antibodies released IL-1 and TNF- when exposed to unsensitized T cells, although increased superoxide release could not be detected. OKT 4a, a murine IgG_2a antibody that reacts with a different T cell epitope (CD4), failed to induce cytokine release from monocytes when cross-linked by T cells or a CD4+ T cell line, even in the presence of IL-2 or IFN-. These data indicate that certain antibodies bound to Fc receptors (FcR) of monocytes may trigger monocyte function when reacting with cells bearing the appropriate target antigens. FcR-mediated signaling resulting in mediator release may be involved in initiating or regulating the immune response. Furthermore, systemically administered monoclonal antibodies may induce inflammatory responses and their attendant symptomatologies via their interaction with FcR-bearing inflammatory cells.     

Induction of β-family chemokines mRNA in human embryonic astrocytes by inflammatory cytokines

The cellular infiltration found during CNS inflammation consists of monocytes and activated T cells, suggesting the presence of cell-specific chemotactic signals during inflammatory responses. Astrocyte chemokine expression might contribute to site-specific leukocyte infiltration within the CNS. To investigate the factors that regulate astrocyte chemokine expression, we examined the ability of human fetal astrocytes to induce -family chemokine mRNA. Astrocyte-derived monocyte chemoattractant protein-1 (MCP-1), RANTES, macrophage inflammatory protein-1 (MIP-1), and MIP-1 mRNA were easily induced by lipopolysaccharide and/or the proinflammatory cytokines (IFN and/or TNF-), respectively. Addition of both IFN and TNF- together did not lead to an additive effect but resulted in the inhibition of MCP-1 and MIP-1 mRNA expression, indicating that interaction between chemokines and cytokines may play a key role in regulating the local immune response of resident and infiltrating cells at the site of lesion. Interestingly, ultraviolet light-inactivated measles virus, but not cytomegalovirus, strongly induced expression of MCP-1, RANTES, MIP-1, and MIP-1 mRNA in human embryonic astrocytes, especially MCP-1 and MIP-1. An association occurs between the -family chemokine expression in astrocytes and inflammatory factors/virus, suggesting a possible role for -family chemokines in the pathogenesis of CNS inflammatory disease.     

Synthesis of Seoul virus RNA and structural proteins in cultured cells

Summary. Seoul virus is a hantavirus that causes hemorrhagic fever with renal syndrome (HFRS). The virion has a tripartite (S, M, and L) negative-stranded RNA genome, which is characteristic of the family Bunyaviridae. However, the molecular basis of virus replication is not well known. We established a Northern blot hybridization (NB) procedure using digoxygenin-labeled RNA probes, to quantitate the hantaviral plus- and minus-strand RNAs separately. Virus RNA replication was analyzed in infected Vero E6 cells. When the Vero E6 cells were infected with Seoul virus strain KI-83-262 (KI) at m.o.i.=0.25, the plus-strand RNA was detected within 1h post-infection (hpi), and the minus-strand RNA was detected subsequently. Using laser confocal microscopy, the nucleocapsid protein (NP) was detected within 2hpi, and accumulated as scattered granules in the cytoplasm until 24hpi. In contrast, the G2 protein first appeared at 8hpi, was immediately transported to the Golgi, and accumulated in the Golgi until 24hpi. Infectious virus particles were released into the medium at 24hhpi. These findings indicate that hantavirus RNA replication starts with the appearance of NP at 2hpi, glycoproteins then accumulate gradually in the Golgi, and virion formation is initiated once the viral RNAs and proteins have accumulated.Received October 10, 2002; accepted April 25, 2003 Published online July 17, 2003     

A comparative immunohistological study of cerebellar enolases

Summary A comparative immunohistological study of the neurone-specific enolase and enolase, demonstrates the exclusive neuronal localization of enolase and its absence from glial cells. In contrast, enolase is located in astroglial cells. The validity of enolase as a neuronal marker and enolase as an astrocytic marker, is confirmed both by a double labelling technique, using antibodies to and to revealed with fluorescence or peroxidase in the same tissue sections, and by immunoelectronmicroscopy.     

Inactivation of Newcastle Disease Virus by β-propiolactone

Summary Newcastle Disease Virus inactivated by -propiolactone (-PL) was found to lose RNA-dependent RNA polymerase activity. -PL was shown to react with both virus proteins and RNA.With 3 Figures     

Identification and quantitation of cortisol metabolites in rat liver homogenate and -slices

Summary Cortisol-1, 2-H³ was incubated with rat liver homogenate and/or rat liver slices in the presence of a NADPH-generating system. The following metabolites could be identified in adult male rats: -cortol, allo--cortol, 3-allo--cortol, 20-hydroxy-cortisol, 11, 17, 20, 21-tetrahydroxy-5-pregnan-3-one, 3-allotetrahydrocortisol, tetrahydrocortisol, trace amounts of allotetrahydrocortisol and two highly polar metabolites only partly identified. In female rats only tetrahydrocortisol, allotetrahydrocortisol and allodihydrocortisol could be detected in significant amounts.The radioactive metabolites mentioned above were localized and quantitated on paper chromatograms by a 4-radiochromatogram scanner. A nearly perfect correlation was found between these results so obtained and those given by liquid-scintillation counting of each metabolite after its elution from the paper.Part of this work was supported by grant n° 695 of the National Fonds voor Wetenschappelijk Geneeskundig Onderzoek.Stagiair of the Nationaal Fonds voor Wetenschappelijk Onderzoek.     

Immunological study of HB-Ag carriers

Summary The serum immunoglobulin levels, the presence of circulating autoantibodies, the number of peripheral atypical lymphocytes and the number of DNA and RNA synthesizing mononuclear cells were studied in a group of healthy HB-Ag (australia Antigen) carriers and in a group of healthy HB-Ag negative control subjects.In the HB-Ag carriers, in spite of the persistent antigenaemia, all these immunological findings were normal (as in the control subjects).     

Der gegenwärtige Stand der Mastzell-Forschung

Zusammenfassung Seit der Erstbeschreibung der MZ durchEhrlich (1877) ist die Kenntnis über die biologische Rolle dieser Zellen wesentlich erweitert worden; diese, mit metachromatischen Granula erfüllten Zellen haben nicht nur die Eigenschaft, Substanzen zu speichern (Mastzellen), sie haben auch die Fähigkeit, biologisch aktive Substanzen zu bilden, diese an das Erfolgsgewebe abzugeben (sekretorische Zellen, Heparinocyten, Histaminocyten) und sind sowohl in morphologischer als auch in funktioneller Hinsicht in den Bauplan der vegetativen nervösen Peripherie mit eingeschlossen (neurohormonale Zellen).     

The relationship between HPV16 and expression of CD44v6, nm23H1 in esophageal squamous cell carcinoma

Summary. The esophageal squamous cell carcinoma (ESCC) has high incidence in Shaanxi Province of China. More and more researches indicated that human papillomavirus type 16 (HPV16) might play an important role in carcinogenesis of ESCC but the relationship between HPV16 and CD44v6, nm23H1 has not been elucidated. HPV16 was detected by amplifying HPV16 E6 gene through polymerase chain reaction (PCR) method and the expression of CD44v6, nm23H1 in 40 ESCCs and fifteen normal esophageal mucosa (NEM) from Shaanxi Province was examined by Streptavidin-Peroxidase (SP) method using monoclonal antibody specific to CD44v6 and nm23H1. The positive rates of HPV16 E6 gene, CD44v6 and nm23H1 were 60% (24/40), 65% (26/40) and 45% (18/40) respectively in ESCCs and 26.67% (4/15), 33.33% (5/15) and 86.67% (13/15) respectively in NEMs. There exited statistical difference for HPV16, CD44v6 and nm23H1 between NEMs and ESCCs respectively (p<0.05). The relationship between HPV16 and the expression of CD44v6 in ESCCs was statistical significance (P=0.021), but no significant correlation was found between HPV16 and the expression of nm23H1 (P=0.436) in ESCCs. The infection rate of HPV16 had no statistical difference in all pathological features we observed, but the expression rates of CD44v6 and nm23H1 had statistical correlation with invasion (p=0.001, 0.013) and lymph nodes metastasis (p=0.014, 0.002) respectively. In different histology grade of ESSCs, the relationship between HPV16 and CD44v6 was statistical significance in grade I (p=0.044) but was not in grade II (p=0.165) and grade III (p=0.658), however as to the expression of nm23H1 there exited no statistical significance in all histology grades of ESCC (p>0.05). The expression rates of CD44v6 and nm23H1 were statistically different between grade I and II (p=0.004, 0.016) respectively and between grade I and grade III (p=0.014, 0.020), but not statistically different between grade II and III (p=0.792, 0.943) respectively. Our data firstly suggested that there existed the statistical relationship between the infection of HPV16 and the expression of CD44v6 in ESCCs and that HPV16 may be involved in invasion and metastasis of ESCC.     

Inhibition of angiogenesis in rats by IL-1 receptor antagonist and selected cytokine antibodies

Daily administration of 50 ng recombinant human interleukin 1-alpha (IL-1), 25 ng IL-8, 50 ng tumor necrosis factor-alpha (TNF-), or 100 ng basic fibroblast growth factor (bFGF) caused intense neovascularization in a rat sponge model. These cytokine-induced neovascular responses were inhibited by coadministration of IL-1 receptor antagonist (IL-1ra; 50 g), IL-8 antiserum (IL-8-AS; 11000), TNF- antibody (TNF-AB; 500 ng), or a monoclonal antibody to bFGF (DG2; 1000 ng), respectively. These data suggest that it is possible to manipulate the angiogenic response elicited by a defined cytokine by its receptor antagonist or neutralizing antibody. In the absence of exogenous cytokines, the sponge-induced angiogenesis was profoundly suppressed by dexamethasone (5g/day), but not modified by IL-1ra, IL-8-AS, TNF-AB, and DG2 alone. However, the combination of these four reagents was able to inhibit the sponge-induced neovascular response almost completely. These findings provide direct evidence that IL-1, IL-8, TNF- and/or bFGF have an intrinsic role in angiogenesis. Further work is necessary to characterize the profile of these cytokines during angiogenesis and to elucidate the nature of their interactions.     

Facilitation by 5-hydroxytryptamine of ATP-activated current in rat pheochromocytoma cells

The effects of 5-hydroxytryptamine (5-HT) on an inward current activated by extracellular ATP were investigated in rat pheochromocytoma PC12 cells. Under whole-cell voltage-clamp conditions 5-HT (10 M) reversibly enhanced the amplitude of the current activated by 30 M ATP. The enhancement may not be due to an increase in the number of functional channels because the current activated by 300 M ATP was not remarkably augmented compared with the current activated by 30 M ATP. The current enhancement by 100 M 5-HT was less obvious than that by 10 M 5-HT. When the current kinetics were compared, activation of the ATP-evoked current was accelerated to the same extent by either 10 or 100 M 5-HT, whereas deactivation was largely more accelerated by 100 M 5-HT. Propranolol (10 M), a 5-HT₁ receptor antagonist, or LY53857 (10 M), a 5-HT₂ receptor antagonist, exerted an agonistic effect: the ATP-activated current was facilitated by these compounds. Metoclopramide (10 M), a 5-HT₃ receptor antagonist, neither facilitated the ATP-activated current, nor blocked the current facilitation by 5-HT. Guanosine 5-O-(2-thiodiphosphate) (GDP[S]) (2 mM), the non-hydrolysable analog of guanosine 5-triphosphate (GTP), or K-252a (2 M), a protein kinase inhibitor, did not affect the facilitation by 5-HT of the ATP-activated current when they were included in the intracellular solution. The ATP-activated current pre-facilitated by 10 M dopamine was not enhanced by 10 M 5-HT. Similarly, the pre-facilitation by 5-HT attenuated the current enhancement by dopamine. The results suggest that 5-HT facilitates the ATP-activated channels through receptors that are not readily classified into conventional subclasses of 5-HT receptors. The reciprocal masking between the current facilitation by 5-HT and that by dopamine, combined with their sensitivities to the compounds involved in the intracellular solution, indicates that the facilitation by 5-HT may share not all, but some, common cellular mechanism with that by dopamine.     

Zur Polypeptidketten-Struktur von Immunglobulinen

Zusammenfassung Die Ergebnisse optischer Drehfähigkeitsmessungen an H- und L-Polypeptidketten normaler und Myelomproteine vom G-Typ werden mitgeteilt und mit den optischen Konstanten kompletter G-Proteine verglichen. Durch Kreuzungen zwischen unspezifischen und spezifischen Polypeptidketten werden die Bedingungen einer spezifischen Rekombination geprüft. Sie sind insbesonders dann gegeben, wenn autologe, d.h. vom gleichen Myelomprotein stammende Polypeptidketten gemischt werden. Die Befunde werden in ihrer Beziehung zum Problem der Antikörperspezifität diskutiert.

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Summary The results of measurements of the optical rotatory dispersion on H- and L-polypeptide chains of normal and myeloma proteins are reported Comparisons of the optical parameters with those of the whole G-proteins were performed. By mixing of normal or unspecific and myeloma or specific polypeptide chains the conditions of specific recombination were examined. Specific recombination occurs especially when autologous chains, that means polypeptide chains of an individual myeloma protein, are mixed. The implications of this finding are discussed with respect of the problem of antibody specifity.

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Herrn Prof. Dr.H. E. Bock zum 65. Geburtstag.     

In situ expression of β1, β3 and β4 integrin subunits in non-neoplastic endothelium and vascular tumours

Endothelial cells play an important role in adhesive interactions between circulating cells and extracellular matrix proteins. In vitro studies have shown that many of these processes are mediated by a superfamily of heterodimeric transmembrane glycoproteins called integrins. The distribution patterns of 1, 3 and 4 integrin subunits in endothelial cells (EC) in situ were examined immunohistochemically on serial forzen sections of a wide range of non-neoplastic tissues and of vascular tumours, both benign and malignant. Expression of the 1 subunit was a constitutive feature of EC. Among the 1-associated subunits, 5 and 6 were broadly distributed in EC, irrespective of vessel size and microenvironment. The 3 subunit displayed intermediate levels of expression with a slight preference for small vessel EC. Presence of 1 was confined to EC of capillaries and venules/small veins. Expression of 2 in EC was inconsistent. With rare exceptions, the 4 chain was absent in EC. The 3 and v subunits were expressed in most EC, though not always concomitantly. In contrast to the 1 chain, however, these integrin subunits were absent in EC of glomerular capillaries and were expressed variably in sinusoidal EC. The 4 chain was evenly present in the great majority of EC, except for those of large vessels. In vascular tumours, the patterns of 1 and 1 to 6 subunit expression generally corresponded to those found in their non-neoplastic counterparts. Expression of 3, v and 4 chains, however, decreased in neoplasia, especially in angiosarcomas. These data show that EC dispose of broad and at the same time differential repertoires of integrin subunits that presumably reflect vessel-type associated functional differences among these cells. In vascular tumours, the orthologous distribution patterns of 1 and 1 to 6 chains are conserved in most instances while the amounts of 3, v and 4 subunits expressed in EC tend to decrease in the course of malignant transformation.Dedicated to Prof. Dr. med. Dres. h.c. Wilhelm Doerr on the occasion of his 80th birthday     

Cationic proteins of human granulocytes Effects on human platelet aggregation and serotonin release

Immune-aggregate and thrombin-mediated [³H]serotonin release from human platelets are shown to be enhanced when platelets are preincubated with the antibacterial chymotrypsin-like cationic protein isolated from human granulocytes. The enhancement is dose dependent and inhibited by heating of the cationic protein. Release with chymotrypsin-like cationic protein alone was not observed, although the protein was shown to micro-aggregate platelets irreversibly by an ADP-dependent reaction. Platelet macro-aggregation induced by immune-aggregate was also enhanced by chymotrypsin-like cationic protein whereas platelet macro-aggregation induced by thrombin was inhibited competitively. Platelet micro-aggregation induced by chymotrypsin-like cationic protein was inhibited when preincubated for more than 5 min with a 2-fold molar excess of-1-antitrypsin. Chymotrypsin-like cationic protein interaction with several platelet reactions suggests a close relationship between neutrophils and platelets in the inflammatory process.     

Altered synthesis of interferon-γ and expression of interferon-γ receptor by peripheral blood mononuclear cells from patients with IgA nephropathy and non-IgA proliferative glomerulonephritis

Previously we reported disease-specific interaction between interferon- (IFN-) and interleukin-4 (IL-4) in patients with IgA nephropathy (IgAN), suggesting the existence of unusual T cell behavior in this disease. In the present study, we investigated characteristic synthesis of interferon- (IFN-) and expression of IFN- receptor (IFN-R) in the peripheral blood mononuclear cells (PBMC) from patients with IgAN and other chronic proliferative glomerulonephritis (PGN). Heparinized peripheral blood samples were obtained from 38 patients with chronic mesangial proliferative glomerulonephritis (CGN; including 24 with IgA nephropathy) and 20 healthy controls. PBMC were isolated by gradient centrifugation and fragments were cultured in Iscove's modified Dulbecco's medium (IMDM) supplemented with 10% fetal calf serum (FCS) for 72 hr. IFN- concentrations in supernatants were evaluated by the enzyme-linked immunosorbent assay (ELISA). Other parts of PBMC pellets were reacted with anti-human IFN-R monoclonal antibody and FITC-labeled anti-mouse second antibody for analysis of IFN-R expression on these cells by FACScan. The remaining PBMC were fractionated into CD4⁺ T cells, CD8⁺ T cells, B cells, NK, cells and macrophages using the MACS cell sorting system. The isolated cells were evaluated for IFN- or IFN-R mRNA expression by the semiquantitative RT-PCR method.In vitro IFN- synthesis was enhanced in patients with CGN, and NK cells were revealed to be responsible for such enhancement. On the other hand, the expression of IFN-R on macrophages was suppressed in CGN patients. These results suggest that impairment of regulation of the IFN- system might be involved in the development of CGN.     

Antigenic relationships between avian paramyxoviruses

Summary The suggested model of antigenic kinship between related paramyxoviruses is based on another concept of antigenic determinant, as compared to the previously suggested combinatorial mathematical model by the authors. According to it, antigenic changes of any determinant do not proceed by leaps but can be changedgradually. Such changed determinant can induce a corre-spondingly changed type of antibodies which still preserve a certain kinship to the original type of the determinant (before its changing) revealed by cross reaction serological tests. Accordingly, there can be families of the determinants differing by degree of relatedness to (or, reversely, by antigenic distance from) the original (ancestor) determinant.In addition to another interpretation of the antigenic kinship, the new mathematical model was used as an approach for revealing phylogenetic relationships between antigenically related viruses.     

Influence of adoptively transferred thioglycollate-elicited peritoneal macrophages on metastasis formation in mice with depressed or stimulated NK activity

The effect of thioglycollate-elicited macrophages (TG-M) on natural killer (NK)-cell activity and metastases formation in mice was investigated. Intravenously (i.v.) inoculated TG-M inhibited spleen NK activity of normal mice and abrogated polyinosinic: polycytidylic (poly IC) induced augmentation of NK cell function. TG-M also inhibited the clearance of i.v.-injected radiolabeled B16 melanoma cells from the lungs of normal or poly IC stimulated mice. Formation of experimental B16 melanoma metastases was dramatically increased in mice pretreated with TG-M. Administration of TG-M increased metatasis formation to a greater extent than anti-asialo GM₁ serum, while anti-asGM₁ serum was more efficient than TG-M in depressing spleen NK cell activity. When mice with low NK reactivity (beige mice or mice treated with anti-asialo GM₁ serum) were inoculated with TG-M, there was a substantial additive augmenting effect on metastasis formation in the lungs. Treatment with poly IC elevated NK-cell activity and had profound antimetastatic effects in normal but not in TG-M pretreated mice. The metastasis augmenting effect of TG-M was fully expressed in poly IC-treated mice as well as in athymic nude mice. Inoculation of proteose peptone-elicited macrophages (PM), unlike TG-M, did not depress NK activity or augment metastasis formation in normal or poly IC-treated mice. However, since the inhibition of NK activity in TG-M-treated mice was relatively weak, and a substantial additional increase in metastases was observed in NK-depressed mice after transfusion of TG-M, it seems unlikely that the TG-M-induced inhibition of NK reactivity is entirely responsible for the augmented formation of metastases. Further studies revealed that i.v. inoculation of TG-M, but not PM, induced intravascular inflammatory reactions, and damage to endothelial cells and basement membrane of the lung vasculature. These reactions may contribute to increased tumor cell extravasation and metastasis formation in mice pretreated with TG-M.