Genetic control of T cell responsiveness to the Friend murine leukemia virus envelope antigen. Identification of class II loci of the H-2 as immune response genes

T cells primed specifically for the envelope glycoprotein of Friend murine leukemia helper virus (F-MuLV) were prepared by immunizing mice with a recombinant vaccinia virus that expressed the entire env gene of F-MuLV. Significant proliferative responses of F-MuLV envelope-specific, H-2a/b T cells were observed when the T cells were stimulated with antigen-pulsed peritoneal exudate cells (PEC) having the b allele at the K, A beta, A alpha, and E beta loci of the H-2. On the other hand, PEC having only the kappa allele at these loci did not induce the envelope-specific T cell proliferation, even when the PEC had the b allele at the E alpha, S, or D loci. F-MuLV envelope-specific proliferation of H-2a/b T cells under the stimulation of antigen-pulsed, H-2a/b PEC was specifically blocked with anti-I-Ab and anti-I-Ek mAbs but not with anti-Kb, anti-Kk, or anti-I-Ak mAbs. Moreover, (B10.MBR x A/WySn)F1 mice that have the b allele only at the K locus but not in I-A subregion were nonresponders to the envelope glycoprotein, and the bm12 mutation at the A beta locus completely abolished the T cell responsiveness to this antigen. These results indicate that proliferative T cells recognize a limited number of epitopes on F-MuLV envelope protein in the context of I-Ab, hybrid I-Ak/b, and/or hybrid I-Ek/b class II MHC molecules but fail to recognize the same envelope protein in the context of I-Ak or I-Ek molecules. This influence of the H-2I region on T cell recognition of the envelope glycoprotein appeared to control in vivo induction of protective immunity against Friend virus complex after immunization with the vaccinia-F-MuLV env vaccine. Thus, these results provide, for the first time, direct evidence for Ir gene-controlled responder/nonresponder phenotypes influencing the immune response to a pathogenic virus of mice.

Different H-2 subregions influence immunization against retrovirus and immunosuppression

Friend murine leukaemia virus complex (FV) causes an immunosuppressive retrovirus-induced disease. In certain mouse strains, FV shows striking similarities to human immunodeficiency virus (HIV) infection in man in that infected mice have severe T-cell immunosuppression but also develop virus-neutralizing antibodies incapable of eliminating infected cells. Previously we noted the influence of mouse major histocompatibility complex (H-2) genes on both FV-induced immunosuppression and on ability to protect mice against FV by immunizing with a vaccinia-Friend murine leukaemia helper virus (F-MuLV) envelope (env) recombinant virus. Here we show that different subregions of H-2 are involved in susceptibility to virus-induced immunosuppression (H-2D subregion) and protective immunization with a recombinant vaccinia virus (H-2K or I-A subregions). Thus, susceptibility to virus-induced immunosuppression does not preclude protection by vaccinia-Friend immunization. The mechanism of protection seems to involve priming of immune T cells, and not initial induction of neutralizing antibodies or cytotoxic T lymphocytes (CTL) (ref.2). Subsequent virus challenge generates a secondary response, resulting in appearance of IgG antibodies and CTL. In human HIV infection there could also be host genetic influences on elements of disease pathogenesis, such as immunosuppression, and on the success of T-cell priming by potential protective vaccines.

Coordination of the levator veli palatini and intrinsic laryngeal muscles: an evoked electromyographic study in the dog

Fourteen dogs anesthetized with sodium pentobarbital were used as experimental animals in an electromyographic study of the functional relationships among the levator veli palatini and the intrinsic laryngeal muscles. The following results were obtained: A single pulse stimulation to the afferent fibers of the pharyngeal branches of the glossopharyngeal nerve evoked ipsilateral reflexes from the levator veli palatini and laryngeal adductor muscles. The laryngeal abductor muscle, however, did not respond to this stimulation. A repetitive pulse stimulation (3-5 Hz) to the afferent fibers of the pharyngeal branches of the glossopharyngeal nerve decreased the level of amplitude of the respiratory discharge from the laryngeal abductor muscle. The reflex discharges in the levator veli palatini muscle were decreased when the respiratory discharges in the laryngeal abductor muscle were enhanced. The present study indicates that there are relationships between the palatal and glottal movements and that the coordinate actions in these regions are influenced by two types of relationships among the palatal and laryngeal muscles. One is the relationship between the levator veli palatini and laryngeal adductor muscles, and the other is that between the levator veli palatini and laryngeal abductor muscle.

Hemolytic anemia and erythroleukemia, two distinct pathogenic effects of Friend MuLV: mapping of the effects to different regions of the viral genome

Two different pathogenic effects of the Friend ecotropic murine leukemia virus (F-MuLV) were distinguished by serial examinations of hematocrits and reticulocyte counts of IRW mice inoculated as newborns. F-MuLV induced hemolytic anemia with increased levels of erythropoiesis, which was detectable as early as 13 days of age, whereas blocked erythroid differentiation, associated with erythroleukemia, was apparent only after 30 days of age. Using strains of Friend-MuLV with different virulences, we constructed recombinant viruses that allowed us to map the hemolytic effect and the ability to induce rapid erythroleukemia to different regions of the viral genome. Moreover, the ability of the virus to induce rapid erythroleukemia appeared to be independent of the presence of severe early hemolytic anemia.

T-lymphocyte priming and protection against Friend leukemia by vaccinia-retrovirus env gene recombinant

The current prevalence of the acquired immune deficiency syndrome in humans has provoked renewed interest in methods of protective immunization against retrovirus-induced diseases. In this study, a vaccinia-retrovirus recombinant vector was constructed to study mechanisms of immune protection against Friend virus leukemia in mice. The envelope (env) gene from Friend murine leukemia virus (F-MuLV) was inserted into the genome of a vaccinia virus expression vector. Infected cells synthesized gp85, the glycosylated primary product of the env gene. Processing to gp70 and p15E, and cell surface localization, were similar to that occurring in cells infected with F-MuLV. Mice inoculated with live recombinant vaccinia virus had an envelope-specific T-cell proliferative response and, after challenge with Friend virus complex, developed neutralizing antibody and cytotoxic T cells (CTL) and were protected against leukemia. In contrast, unimmunized and control groups developed a delayed neutralizing antibody response, but no detectable CTL, and succumbed to leukemia. Genes of the major histocompatibility complex influenced protection induced by the vaccinia recombinant but not that induced by attenuated N-tropic Friend virus.

Influence of the murine MHC (H-2) on Friend leukemia virus-induced immunosuppression

Friend murine leukemia virus complex (FV)-induced immunosuppression was studied by assaying splenic anti-SRBC PFC responses and plasma antibody titers in mice at various times after FV inoculation. Genes located within the H-2 complex were found to influence resistance to FV-induced immunosuppression. Near normal responses were observed in mice having the H-2a/b or H-2b/b genotype, whereas mice having the H-2a/a genotype were suppressed. This H-2 effect was observed not only in mice having heterozygous C57BL/10 X A background genes, including Rfv-3r/s, but also was apparent in mice having homozygous A-strain background genes, including Rfv-3s/s. Therefore, the Rfv-3 gene did not appear to convey resistance to FV-induced immunosuppression. The suppression in susceptible H-2a/a mice was characterized by a partial suppression of the IgM response and a profound suppression of both the primary and secondary IgG responses. Neither splenomegaly nor viremia alone appeared to be sufficient for the induction or maintenance of the immunosuppression. The mechanism of suppression was unclear, but both B lymphocyte and T lymphocyte functions appeared to be altered.

Analysis of two strains of Friend murine leukemia viruses differing in ability to induce early splenomegaly: lack of relationship with generation of recombinant mink cell focus-forming viruses

Friend murine leukemia helper viruses (F-MuLV) 57 and B3 were indistinguishable by genomic structural analyses with RNase T1-resistant oligonucleotide fingerprinting and by antigenic reactivity with a panel of 31 monoclonal antibodies directed against murine leukemia viruses. Nevertheless, F-MuLV 57 and B3 had strikingly different virulences. Approximately 2 months after inoculation, IRW and NFS/N mice inoculated as newborns with F-MuLV 57 had gross splenomegaly caused by erythroid proliferation. In contrast, an equivalent dose of F-MuLV B3 induced spleen or lymph node enlargement 4 to 13 months after inoculation. Although most cases of spleen enlargement in F-MuLV B3-inoculated mice were due to erythroid proliferation, lymphoid or myeloid proliferation was also frequently observed. The replication of both F-MuLV 57 and B3 was equally efficient, and both viruses generated recombinant dual-tropic mink cell focus-forming (MCF) viruses with the same kinetics and efficiency. Moreover, MCF viruses induced by F-MuLV 57 and B3 had the same antigenic patterns. Therefore, the ability of F-MuLV to induce early splenomegaly did not correlate with the generation of recombinant MCF viruses.

Identification of scrapie prion protein-specific mRNA in scrapie-infected and uninfected brain

To date no nucleic acid has been found in the purified infectious agent which causes the spongiform encephalopathy known as scrapie. In an attempt to identify a unique scrapie virus-associated messenger RNA in tissues of infected animals, we have synthesized an oligonucleotide probe complementary to the mRNA sequence corresponding to the amino-acid sequence of the prion protein, PrP27-30 (ref. 1). We report here that, with this probe, a complementary DNA clone representing PrP27-30 was obtained from scrapie-infected mouse brain; the DNA sequence of this clone could be translated into a protein that matches exactly the published sequence of PrP27-30. The cDNA clone hybridized to a single 2.4-2.5-kilobase (kb) mRNA from both normal and scrapie-infected brain. Thus, the PrP27-30 mRNA is not uniquely associated with scrapie infectivity, suggesting that PrP27-30 may be a normal component of mouse and hamster brain.

Use of a focal immunofluorescence assay on live cells for quantitation of retroviruses: distinction of host range classes in virus mixtures and biological cloning of dual-tropic murine leukemia viruses

A rapid and sensitive focal immunofluorescence assay (FIA) using monoclonal antibodies or heterologous antisera was employed for detection and biological cloning of viruses capable of inducing viral antigens on cell surfaces. The FIA was performed directly on a variety of live cells in tissue culture dishes and was used successfully with C-type murine leukemia viruses (MuLV) of different tropism including ecotropic, xenotropic, amphotropic, and dual-tropic recombinant mink cell focus-inducing (MCF) viruses. With the FIA, we were able to titrate and distinguish ecotropic Friend-MuLV and Friend-MCF viruses present in mixtures. Dual-tropic MCF viruses could be specifically detected directly in mouse cells by using MCF-specific monoclonal antibodies. These antibodies replaced the requirement for production of typical MCF cytopathic effect in mink cells for MCF virus detection, and also allowed efficient titration in mouse cells of MCF virions pseudotyped with ecotropic envelope proteins. Furthermore, by picking foci of fluorescent cells and using their cell-free viral progeny, MCF viruses were cloned from complex pseudotypic mixtures. This allowed the cloning of viruses present at low frequency in heterogeneous mixtures obtained from leukemic tissues.

Pseudotyping of dual-tropic recombinant viruses generated by infection of mice with different ecotropic murine leukemia viruses

Using a new focal immunofluorescence assay (FIA) with monoclonal antibodies, dual-tropic recombinant mink cell focus-inducing (MCF) retroviruses were specifically detected directly in mouse cells. With the FIA, MCF and ecotropic murine leukemia virus (MuLV) infectious centers were quantitated in noninoculated AKR/J mice and in mice inoculated with either ecotropic Friend- or Moloney-MuLV. Comparison of the titers obtained in mouse and mink cells suggested that pseudotyping of MCF viruses with ecotropic MuLV envelopes occurred at different levels in these three mouse models. Adult and newborn IRW mice inoculated with Friend-MuLV produced MCF viruses which were mostly pseudotyped with ecotropic MuLV envelopes. Newborn IRW mice inoculated with Moloney-MuLV produced MCF viruses in both spleen and thymus. Most Moloney-MCF viruses from spleens were pseudotyped with ecotropic MuLV envelopes, whereas thymic Moloney-MCF viruses were not. Noninoculated AKR/J mice spontaneously produced MCF virus at least 2 months before the onset of organ enlargement, and the majority of MCF viruses in both spleens and thymuses of these mice did not appear to be pseudotyped.

Leukemia induction by a new strain of Friend mink cell focus-inducing virus: synergistic effect of Friend ecotropic murine leukemia virus

A new strain of Friend recombinant mink cell focus-inducing retrovirus, FMCF -1-E, was found to induce leukemias in NFS and IRW mice. Although the isolate was obtained from a stock of FMCF -1 ( Troxler et al., J. Exp. Med. 148:639-653, 1978), FMCF -1-E was distinguishable from FMCF -1 by oligonucleotide fingerprinting and antigenic analysis, using monoclonal antibodies. These analyses suggested that FMCF -1-E is a distinct FMCF isolate rather than a simple variant of FMCF -1. After neonatal inoculation, the latency for leukemia induction was 3 to 8 months. A similar long latency was also seen when Friend murine leukemia virus 57 was inoculated into adult (6-week-old) IRW mice. However, sequential inoculation of FMCF -1-E at birth followed by Friend murine leukemia 57 at 6 weeks of age led to a shortened latency period (2.5 to 4 months). Only neonatal inoculation of Friend murine leukemia virus 57 was able to induce a more rapid appearance of leukemia. The leukemia cell type in the majority of cases, regardless of virus inoculation protocol, was erythroid, but occasional myeloid, lymphoid, and mixed leukemias were also observed. In contrast to NFS and IRW mice, BALB/c mice were resistant to leukemia induction by FMCF -1-E and also showed some transient resistance to leukemia induction by Friend murine leukemia virus 57.

Visual training for velopharyngeal closure in cleft palate patients; a fibrescopic procedure (preliminary report)

Velopharyngeal closure in various tasks was examined in 59 cleft palate patients with persistent velopharyngeal incompetence using nasopharyngeal fibrescopic (NPF) examination. The degree of velopharyngeal closure was analyzed according to the categories reported previously by Yamaoka (1973) and Matsuya et al. (1979). The NPF self-training system was developed and applied to those patients so as to investigate a longitudinal effect of the NPF in velopharyngeal closure mechanism. The training was performed every two weeks for nearly one year. The results indicated that the patient who showed complete velopharyngeal closure during blowing and/or several productions of speech samples could attain a much better improvement in all speech samples after one year of self-training. On the other hand, the patients who did not show complete velopharyngeal closure during all tasks, failed to improve the velopharyngeal closing mechanism. The ability to close the velopharynx during swallowing was seen in all patients examined. However, it appeared to have nothing to do with the prognosis of velopharyngeal closure. The data suggested that the NPF self-training system provided a strong neuro-muscular signal for velopharyngeal movement. Besides, it was considered that the NPF was a useful tool for activation of velopharyngeal activity by way of visual feed-back control.

Effect of murine host genotype on MCF virus expression, latency, and leukemia cell type of leukemias induced by Friend murine leukemia helper virus

Leukemias induced by neonatal inoculations of several mouse strains with different strains of Friend murine leukemia helper virus (F-MuLV) were followed for time of disease onset, cytochemical analysis of predominant cell types in leukemic organs, and expression of infectious mink cell focus-inducing (MCF) viruses detected by mink cell foci or MCF-specific monoclonal antibodies. Most BALB.B and IRW mice had a rapidly appearing, severe anemia and hepatosplenomegaly consisting of erythroid cells. MCF viruses were usually isolated from enlarged spleens of IRW mice. In contrast, C57BL/10 mice had a lower incidence of disease and much slower course. Splenomegaly and lymphadenopathy with mild anemia were seen, and the predominant cell types were either myeloid (chloroleukemia) or lymphoid. MCF viruses were never isolated from this mouse strain. (C57BL/10 X IRW)F1 mice were intermediate in latency, but all mice had disease by 8 months. Myeloid, lymphoid, and some mixed leukemias with an erythroid component were observed, but in no case did we see the severe anemia or pure erythroid involvement typical of IRW and BALB.B mice. MCF viruses were, however, isolated from 22% of these mice regardless of leukemia cell type. DBA/2 mice had a disease pattern similar to the (C57BL/10 X IRW)F1 mice, and MCF viruses were isolated from three of six mice tested. Inoculation of IRW mice with the low virulence B3 strain of F-MuLV produced disease with a longer latency than F-MuLV 57, but similar cell types were transformed by both viruses. In vitro cell lines were derived from 14 mice, and most were tumorigenic in vivo. Three lines released infectious MCF virus, and three others expressed MCF-specific cell surface antigens but did not release virus. Eight lines expressed no MCF infectious virus or viral antigens. Several lines released infectious xenotropic viruses and/or expressed xenotropic MuLV cell surface antigens recognized by monoclonal antibodies reactive with xenotropic viruses. The lack of MCF expression in many primary leukemic tissues as well as in in vitro derived leukemia cell lines of C57BL/10 and (B10 X IRW)F1 mice suggested that MCF virus generation and expression may not be required for leukemogenesis in some mouse strains or in some hemopoietic lineages.

Characterization of monoclonal antibodies reactive with murine leukemia viruses: use in analysis of strains of friend MCF and Friend ecotropic murine leukemia virus

Sixteen mouse and rat monoclonal antibodies reactive with gag or env proteins of Friend murine leukemia virus (F-MuLV) or recombinant MCF viruses related to F-MuLV were derived. Specificity of these was determined by immunofluorescence, immunoprecipitation, and reactivity with viral proteins blotted onto nitrocellulose paper. Seven antibodies reacted with envelope protein antigens of certain nonecotropic viruses only. Nine antibodies reacted with both ecotropic and nonecotropic viruses. Of this latter group, three were antienvelope, four were anti-p15, one was anti-p12, and one was anti-p30 in specificity. When tested as a panel against 10 strains of F-MuLV, these antibodies could distinguish seven different antigenic patterns. However, all 10 strains retained reactivity for three anti-gp70 antibodies uniquely specific for Friend and Rauscher MuLVs. Our antibody panel could also identify MCF viruses isolated from mice neonatally inoculated with F-MuLV as recombinants related to a particular F-MuLV strain based on identity of p15 gag antigenic profiles. However, recombinant viruses lacked several envelope antigens always associated with F-MuLV and instead had new envelope reactivities. These anti-MCF monoclonal antibodies detected no shared envelope antigens between MCF and xenotropic viruses isolated from mice inoculated with F-MuLV, however many of them did react with MCF viruses derived from AKR mice and NFS mice congenic for endogenous ecotropic virus loci.

Persistence of infectious Friend virus in spleens of mice after spontaneous recovery from virus-induced erythroleukemia

Persistent infectious virus was detected in the majority of spleens of (C57BL/10 X A.BY)F1 mice after spontaneous recovery from Friend virus-induced erythroleukeima. The Friend murine leukemia helper virus (F-MuLV) was detected in titers up to 3 X 10(5) PFU/g of spleen. The defective spleen focus-forming virus (SFFV) was present in much lower titers and could be detected in cell-free spleen homogenates only after amplification of virus titer by growth of virus in vitro on SC1 cells. The incidence of cells producing F-MuLV alone in spleens after recovery from leukemia was 0.003 to 0.3%, and the incidence of cells producing both F-MuLV and SFFV was less than 0.0001 to 0.01%. In most recovered mouse spleens there appeared to be a selective reduction of SFFV relative to F-MuLV.

Antibody-induced modulation of Friend virus cell surface antigens decreases virus production by persistent erythroleukemia cells: influence of the Rfv-3 gene

The Rfv-3 gene was found to influence the level of Friend leukemia virus production in spleens of leukemic mice later than 30 days after virus inoculation. Rfv-3r/s mice [(B10.A X A)F1 and (B10.A X A.BY)F1] had decreased spleen virus levels 30-90 days after virus inoculation compared to Rfv-3s/s mice [A.BY, A, BALB.B, and (BALB/c X A)F1)]. In (B10.A X A)F1 X A backcross mice the spleen virus titer segregated with the level of viremia. The Rfv-3 gene appeared to act by controlling anti-Friend virus antibody production. The interaction of antiviral antibody with infected cells led to a decrease in release of infectious virus by late leukemic spleen cells in Rfv-3r/s mice to 1/300th that in Rfv-3s/s mice. This decrease in virus release appeared to be due to interference with the virus budding process due to antibody-mediated modulation of virus-induced cell surface antigens.

The course of facial nerve innervation for the levator veli palatini muscle

The present study was designed to determine the motor nerve pathway of the facial nerve to the levator veli palatini muscle. The experiments were carried out on 10 anesthetized rhesus monkeys. Recorded and analyzed were evoked EMG responses of the levator veli palatini and the orbicularis oris muscles by electrical stimulation to both the facial nerve and its branch within the cranium. Muscle action potentials (M-waves) from the two muscles could be recognized on stimulating the facial nerve at the petrosal area of the temporal bone. On stimulating the greater petrosal nerve, M-waves from the levator muscle could be elicited. By cutting off the greater petrosal nerve at the middle cranial fossa, M-waves from the levator muscle completely disappeared on stimulating the facial nerve at the petrosal area. Results indicated that the course of the facial nerve for the levator veli palatini muscle is through the greater petrosal nerve.

Metastatic choriocarcinoma involving the gingiva

A case of metastatic choriocarcinoma involving the mandible is reported. This case is analyzed for the potentiality of immunologic defense by utilizing tuberculin test and scoring the rate of blast formation of peripheral blood lymphocytes by phytohemagglutinin, resulting in a greatly decreased ability of cellular immunity.

In vivo studies on the cellular source of migration inhibitory factor in mice with delayed hypersensitivity

Mice sensitized intravenously with 300 microgram of BCG cell walls in Drakeol-Tween 80 and challenged intravenously 3 weeks later with 50 mg of old tuberculin released migration inhibitory factor (MIF) into the circulating blood in quantities that could be detected in serum dilutions of 1:64 to 1:128. When thymus-derived lymphocytes (T-cells) were absent at the time of sensitization, as in neonatally thymectomized mice or in athymic nude mice, detectable amounts of MIF were not formed. Sensitized mice treated with either anti-theta serum or anti-bone marrow-derived lymphocyte (B-cell) serum before intravenous challenge with old tuberculin released reduced amounts of MIF into the circulation. Mice lethally irradiated, reconstituted with B-cells, sensitized with BCG cell walls, and then challenged intravenously 3 weeks later with old tuberculin did not release MIF into the circulation. When T-cells were injected at least 10 days before challenge, however, MIF appeared.

Roles of the facial, glossopharyngeal and vagus nerves in velopharyngeal movement

The present study was designed to clarify the role of the motor nerves in velopharyngeal movements. Experiments were carried out on 15 anesthetized rhesus monkeys on the assumption that their velopharyngeal structures are similar to those of human beings. The pattern and degree of velopharyngeal movements with stimulation to the facial, glossopharyngeal, and vagus nerves in the petrosal area were analyzed by means of fiberscopic observations. The results obtained were as follows: 1. Velopharyngeal movements were most active with stimulation to the vagus, then the glossopharyngeal, and, finally, the facial nerve. 2. Complete closure by unilateral stimulation was elicited only by the vagus nerve and not the facial or glossopharyngeal nerves. 3. The pattern of velopharyngeal movements observed when stimulating the facial nerve was quite different from those seen when the glossopharyngeal or the vagus nerve was stimulated. That is, movements in a plane at the upper part of the nasopharynx were observed on stimulating the facial nerve while upward movements from all of the velopharyngeal structures were seen when the glossopharyngeal or vagus nerve was stimulated. 4. Combined stimulation to the nerves sometimes resulted in additive effects on velopharyngeal movements, but these could be recognized in only a few cases. This study reveals that the motor nerves innervating the velopharyngeal muscles play different roles in velopharyngeal movements.

The motor nerve supply of the velopharyngeal muscles

The present study attempted to clarify the motor nerve supply of the velopharyngeal muscles. Experiments were carried out on 20 anesthetized rhesus monkeys. Evoked EMG responses of the levator veli palatini, uvula, and superior constrictor pharyngeus muscles, which seem to contribute to velopharyngeal closure, were analyzed by stimulating the cranial nerves within the skull. Results were as follows: 1. Muscle action potentials (M-waves) from the selected muscles could be recognized on stimulating the facial, glossopharyngeal, and vagus nerves at the petrosal area of the temporal bone but were not noted upon accessory nerve stimulation. 2. At maximal stimulation, the vagus gave a greater increase in muscle amplitude than the other nerves studied. This was followed by the glossopharyngeal with the facial nerve producing the least increase in amplitude. 3. Also at maximal stimulation, latencies in the response of the levator veli palatini and uvula muscles were reduced to the greatest degree by stimulation of the vagus, to a lesser extent for the glossopharyngeal, and least for the facial nerve. 4. On stimulating the facial nerve below the stylomastoid foramen, M-waves could not be recognized. From the present study, it was concluded that the levator veli palatini, uvula, and superior constrictor pharyngeus muscles are double innervated by the facial nerve and branches of the pharyngeal plexus derived from the glossopharyngeal and vagus nerves and that the facial nerve plays an important role as one of the motor nerves in movements responsible for velopharyngeal closure.

Tumor suppression by a lymphokine released into the circulation of mice with delayed hypersensitivity

Lymphokines such as migration inhibitory factor and type II interferon were released into the circulation of tuberculin-sensitive mice after iv injection of old tuberculin. Daily administration of such sera into the tumor sites of mice given implants of sarcoma MC-36 markedly suppressed tumor growth.

Two new inhibitory activities in blood of mice with delayed hypersensitivity, after challenge with specific antigen

In addition to the activities associated with migration inhibitory factor and type II interferon, two other inhibitory activities have been found in the sera of mice infected intravenously with BCG and 3 weeks later challenged intravenously with old tuberculin. Growth of three bacteria, Streptococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, and one yeast, Candida albicans, was inhibited in vitro by a factor or factors in the serum. Also, hematopoiesis of mouse bone marrow cells in a soft agar medium was suppressed by the serum.

Lymphoid cells in delayed hypersensitivity. 3. The influence of x-irradiation on passive transfer and on in vitro production of soluble mediators

X-irradiation up to 480 R does not inhibit either adoptive transfer of delayed hypersensitivity or production in vitro of soluble mediators, such as migration-inhibitory factor (MIF). Above that dosage and as high as 3000 R, adoptive transfer is inhibited, but production of MIF is not. An increase in skin response occurred when 24-48 hr were allowed to elapse after intravenous transfer and before skin testing. Treatment of recipients with colchicine at the time of adoptive transfer inhibited the development of a skin reaction to specific antigen.