Homozygosity at the major histocompatibility complex is required for optimal immunogenicity of bone marrow cell allografts in irradiated rats

Hemopoietic histocompatibility (Hh) Genes associated with the H-2 region control the antigenicity of hemopoietic cell grafts in the mouse. We have tested for similar genes in rats. Wistar Furth (WF, RTlu) or Lewis (LEW RTl1) bone marrow cell grafts did not proliferate in spleens of lethally irradiated (WFxLEW) F1 hybrid rats as assessed by measuring the incorporation of 5-iodo-2' deoxyuridine - 125I (IUdR) into recipient spleens 5 days after transplantation. In contrast, (WFxLEW) F1 hybrid marrow cells grew well in both WF and LEW parental strain hosts. (WFxLEW) F1 or (WFxLEW) F1 hybrid rats were backcrossed to WF parental strain rats to produce progeny, either homozygous, or heterozygous for the MHC. The RTl type of 46 individual backcross progeny was determined using a 5 day mixed-lymphocyte reaction (MLR). Correlation between RTl type and growth of marrow grafts of individual backcross rats were determined by using each rat as a bone marrow donor for irradiated LEW hosts. Marrow grafts from rats heterozygous for RTl were accepted in all 25 cases, whereas, grafts from 19 to 21 homozygous donors were rejected by the LEW hosts. Thus, homozygosity, for Hh determinants in or near the RTl region appears to be necessary for optimal immunogenicity of bone marrow allografts.

EAE in rat bone marrow chimeras: analysis of the cellular mechanism of BN resistance

Unlike Lewis strain, BN rats do not develop EAE when given 10 microgram GPBP + CFA. Their resistance is mediated via the MHC-linked gene Ir-EAE-. The cellular mechanism of BN resistance can be probed using bone marrow chimeras between susceptible LBNF1 strain and BN. F1 leads to BN chimeras can develop EAE when actively sensitized with GPBP + CFA, but are markedly more resistant than F1 leads to F1. By contrast, F1 leads to BN chimeras are highly susceptible to passively transferred EAE from an F1 donor. F1 rats reconstituted with BN bone marrow, i.e., BN leads to F1 chimeras, are completely resistant to EAE induced by active sensitization, but they too are susceptible to passively transferred EAE. We argue that Ir-EAE- blocks the development of T cells reactive to self myelin, and that this occurs at the level of macrophage presentation of antigen to the T cell. Suppressor mechanisms do not appear to play a major role.

EAE in rat bone marrow chimeras: analysis of the cellular mechanism of BN resistance

Unlike Lewis strain, BN rats do not develop EAE when given 10 microgram GPBP + CFA. Their resistance is mediated via the MHC-linked gene Ir-EAE-. The cellular mechanism of BN resistance can be probed using bone marrow chimeras between susceptible LBNF1 strain and BN. F1 leads to BN chimeras can develop EAE when actively sensitized with GPBP + CFA, but are markedly more resistant than F1 leads to F1. By contrast, F1 leads to BN chimeras are highly susceptible to passively transferred EAE from an F1 donor. F1 rats reconstituted with BN bone marrow, i.e., BN leads to F1 chimeras, are completely resistant to EAE induced by active sensitization, but they too are susceptible to passively transferred EAE. We argue that Ir-EAE- blocks the development of T cells reactive to self myelin, and that this occurs at the level of macrophage presentation of antigen to the T cell. Suppressor mechanisms do not appear to play a major role.

An ultrastructural study of a jejunal inflammatory fibroid polyp

Ultrastructural appearances of a small intestinal inflammatory fibroid polyp are reported. There is a vascular scaffolding, with interstices which contain regular and fibrous long-spacing type collagen, condensed lamellar basement membrane fibroblasts, basophils, some eosinophils and histiocytes. In addition other cells less easily characterized but believed to be of an endothelial and primitive mesenchymal cell nature are recognized. Possible origins of the polyp are considered.

Congenital convex pes valgus: results of an early comprehensive release and a review of congenital vertical talus at Richmond Crippled Children's Hospital and the University of Alabama in Birmingham

Nineteen patients with 28 feet with congenital vertical talus were reviewed. The male to female ratio was equal, and associated congenital abnormalities were found in 15 of the 19 patients. No genetic pattern was established. Fifteen of the 16 surgically corrected feet were reevaluated, with an average follow-up of 60 months. Ten of the 15 feet were found to be in the good to excellent category, and five were rated poor. Twelve of 12 feet treated by cast correction were poor. Poor prognostic signs include late age of surgical correction, associated arthrogryposis and cerebral palsy, and an increased space between the calcaneus and cuboid. Best results occurred in those patients who had early surgical correction, after 4 to 6 months of serial casting, using magnification. Surgical technique which yielded the best results involved total release of the talus from the posterior, medial, and lateral approach, with reduction of the talocalcaneal as well as the talonavicular joints with multiple pin fixation. Lengthening of the Achilles tendon, extensor tendons, and peroneal tendons and transfer of the anterior tibialis to the navicular are recommended. Navicular excision was not found to be necessary. Surgical results in those patients over 3 1/2 years of age were found to be poor, and these individuals were considered for salvage procedures using a subtalar extra articular arthrodesis, excision of the navicular, or triple arthrodesis, depending on age.

Linkage of severity of experimental allergic encephalomyelitis to the rat major histocompatibility locus

The incidence of EAE is determined by Ir-EAE, a gene linked to the rat MHC. EAE severity can be assessed by quantitative clinical and pathologic measures. Using these measures, one can say that disease severity in LBNF1 is approximately one-tenth that in Lewis. Analysis of LBNF2, LBC, BNBC, and parental Lewis strain reveals that severity is primarily a function of dose of Lewis MHC alleles. Non-MHC genes have a small but discernable effect.

Linkage of severity of experimental allergic encephalomyelitis to the rat major histocompatibility locus

The incidence of EAE is determined by Ir-EAE, a gene linked to the rat MHC. EAE severity can be assessed by quantitative clinical and pathologic measures. Using these measures, one can say that disease severity in LBNF1 is approximately one-tenth that in Lewis. Analysis of LBNF2, LBC, BNBC, and parental Lewis strain reveals that severity is primarily a function of dose of Lewis MHC alleles. Non-MHC genes have a small but discernable effect.

A study of the benefits and acceptability of ambulation in spontaneous labour

A prospective study of 300 consecutive deliveries has been made to assess the benefits and acceptability of ambulation during spontaneous labour. Ambulation during the first stage occurred in 48 patients with 55 non-ambulant patients acting as controls. No difference in the length of first or second stage, incidence of fetal distress or mode of delivery was observed. In spite of the lack of apparent advantage to the fetal condition, ambulation was acceptable to both patients and nursing staff and should not be discouraged.

In vivo demyelination by antimyelin antibodies

Central nervous system (CNS) myelin-specific antiserum was capable of initiating primary demyelination within 24 h following injection into the dorsal column of guinea pig spinal cord. Control serum injected in the same manner did not produce demyelination. The demyelinating lesions occurred as focal linear plaques of completely denuded intact axons surrounded by partially demyelinated and myelinated normal axons. Antiserum-mediated demyelination was followed by mononuclear cell infiltration 7-10 days later. Ultrastructural examination revealed vesiculation of myelin followed by cleavage of myelin lamellae at the intraperiod line. Remyelination began between 7 and 10 days following injection and correlated well with clinical evidence of recovery. The results of this study point to the importance of circulating antimyelin antibodies in the pathogenesis of demyelinating encephalitis. The model represents an in vivo approach to the study of the pathogenesis of immune-mediated myelinolysis in demyelinating disorders like multiple sclerosis (MS), subacute sclerosing panencephalitis (SSPE), and canine distemper encephalitis (CDE).

Spontaneous diabetes mellitus: reversal and prevention in the BB/W rat with antiserum to rat lymphocytes

Injections of rabbit antiserum to rat lymphocytes reversed hyperglycemia in 36 percent of spontaneously diabetic rats (Bio Breeding/Worcester) and prevented diabetes in susceptible nondiabetic controls. These findings strengthen the hypothesis that cell-mediated autoimmunity plays a role in the pathogenesis of diabetes in this animal model that mimics many morpholigic and physiologic characteristics of human insulin-dependent diabetes mellitus.

Spontaneous diabetes in the gnotobiotic BB/W rat

To determine the influence of infectious agents on the initiation of diabetes in the spontaneously diabetic Bio-Breeding/Worcester (BB/W) rat, susceptible rats were raised in a germ-free environment. Between 2 and 3 mo of age, 3 of 12 pups became diabetic. Histologic examination of the pancreas revealed insulitis or end-stage islets. Culture and smears from various tissues were negative for bacteria or parasites. Serum vital antibody titers for all known rat viruses were undetectable. These data suggest that the diabetic syndrome of the BB/W rat is not dependent on recognized infectious agents.

Prevention and treatment of endometrial disease in climacteric women receiving oestrogen therapy

The treatment regimens are described in 74 patients with endometrial disease among 850 climacteric women receiving oestrogen therapy. Cystic hyperplasia was associated with unopposed oestrogen therapy without progestagen. Two courses of 21 days of 5 mg norethisterone daily caused reversion to normal in all 57 cases of cystic hyperplasia and 6 of the 8 cases of atypical hyperplasia. 4 cases of endometrial carcinoma referred from elsewhere demonstrated the problems of inappropriate and unsupervised unopposed oestrogen therapy and the difficulty in distinguishing severe hyperplasia from malignancy. Cyclical low-dose oestrogen therapy with 7--13 days of progestagen does not seem to increase the risk of endometrial hyperplasia or carcinoma.

An ultrastructural study of a nasal haemangioendothelioma

A malignant haemangioendothelioma of the nose has been examined with the electron microscope. The tumour is predominantly poorly differentiated with only little evidence of its vascular ancestry identified. The cells are polygonal with a wide spectrum of organelles, including microfilaments. A conspicuous feature was the presence of cytoplasmic fenestrae developing into intracytoplasmic vacuolated spaces. The satisfactory progress of this patient is noted, and the value of electron microscopy in enabling an early and accurate diagnosis of this tumour to be made is emphasised.

Influence of genetic factors on natural resistance of mice to Pseudomonas aeruginosa

In order to determine whether genetic background influences natural resistance to Pseudomonas aeruginosa, a series of 16 different strains of inbred mice were challenged intraperitoneally with P. aeruginosa. Significantly greater natural resistance to infection was found in mice of C3H background genome than in mice of A background genome. This phenomenon was documented for two different strains of P. aeruginosa but could not be demonstrated in control studies in which mice were intraperitoneally challenged with Staphylococcus aureus or Escherichia coli. The enhanced resistance of C3H mice was independent of currently defined haplotypes at the H-2 locus. The killing activity of serum against Pseudomonas was not greater in C3H mice than in A mice. The extension of these findings to disease in humans suggests that the particular susceptibility of certain populations of patients to Pseudomonas may be partially related to genetic factors.

A light and electron microscopic study of an ovarian and rectal carcinoid

An ovarian and rectal carcinoid within the same person is described. The ovarian carcinoid is non-argentaffinic with typical regular granules. The rectal tumour consists of two types of APUD cells, some argentaffinic and diazo-positive, whilst others are non-argyrophilic. These features are mirrored ultrastructurally, some cells containing the large pleomorphic argentaffinic granules while others have smaller regular granules. In addition, focal aggregates of microfilaments were found in both tumour types. These findings are discussed in terms of the APUD concept. The similarities of the APUD tumour cells to D1 APUD cells of the duodenum is highlighted, and an alternative explanation for their derivation is proposed.

Procedure for processing of central nervous system tissue for immunofluorescence, light, and electron microscopic evaluation

A rapid and simple procedure has been developed for the simultaneous localization of viral antigen in central nervous system tissues by immunofluorescnece and concomitant correlation with viral induced lesions in the contralateral brain hemisphere. In this study, one-half of the brain was excised from the dog under deep general anesthesia and samples were collected for immunofluorescence by snap freezing in liquid nitrogen. The other half of the brain was perfused under pressure with a buffered glutaraldehyde-paraformaldehyde mixture for subsequent light microscopic and ultrastructural evaluation. The technique was useful in studying central nervous system diseases in large outbred experimental subjects in which economic and other considerations developed for tissue processing in rodents was not feasible.

Increased frequency of HLA-DRW4 in chronic active hepatitis

HLA-A, B, C and DRw typing was performed on peripheral blood lymphocytes of 17 adults with the diagnosis of chronic active hepatitis made by liver biopsy as the only criterion for study. An increase in the frequency of HLA-DRw4 (71 vs. 24%, p less than 0.005) was observed, but there was no increased frequency of HLA-A1, B8 or any other HLA locus specificity.

Sex differences in the multiple-dose streptozotocin model of diabetes

The hyperglycemic response to multiple low-dose SZ injections was measured in castrated and non-castrated male and female mice with or without testosterone treatment. On the 10th day of the experiment, control males had plasma glucose concentrations that were significantly higher than those of control females. Castration of males decreased the hyperglycemic response, while testosterone treatment restored it. The glucose concentrations in castrated females were significantly greater than control females, but not different from castrated males. Testosterone administration to castrated or non-castrated females increased the hyperglycemic response to that seen in control males and in testosterone-treated castrated males. Thus, castration negates the sex difference in the hyperglycemic response to the multiple low-dose SZ injections. Testosterone enhances the hyperglycemic response in castrated or non-castrated females, and in castrated males.

Viral studies in streptozotocin-induced pancreatic insulitis

Multiple injections of streptozotocin to Charles River (CD-1) Laboratory mice resulted in a syndrome characterised by diabetes mellitus, insulitis and the induction of endogenous type C viruses in pancreatic beta cells. Within one week after the completion of five intraperitoneal injections of streptozotocin, the CD-1 mice exhibited irreversible hyperglycaemia and insulinopaenia. Light microscopic studies of pancreata from mice sacrificed at this time demonstrated insulitis and beta cell necrosis. Electron microscopic studies revealed spherical and atypical cylindrical type C viruses and occasional clusters of intracisternal type A viruses exclusively within beta cells. To clarify the identification of the type C viruses and their role in the genesis of the insulitis, type C virus specific antigens were identified within islet cells by immune fluorescence at various intervals after streptozotocin administration. Immune fluorescence studies demonstrated the presence of type C virus antigens within islets from streptozotocin treated mice but not in buffer-injected controls. Time course studies suggested that type C virus induction may precede the appearance of insulitis by two days and that insulitis is consistently accompanied by the presence of virus positive islet cells.

Streptozotocin-induced pancreatic insulitis in mice. Morphologic and physiologic studies

Pancreatic insulitis and diabetes mellitus were induced in Charles River CD-1 mice with five subdiabetogenic injections of streptozotocin. Plasma glucose and immunoreactive insulin levels were measured and animals were sacrificed at intervals for morphologic studies of pancreatic islets and measurements of extractable pancreatic immunoreactive insulin. Light microscopy revealed striking insulitis, 5 to 6 days after streptozotocin injections, with cell necrosis and eventual islet atrophy due to beta-cell necrosis, and numerous type C viruses within many of the surviving beta-cells. Light microscopic immunoperoxidase stains of islet cell hormones and electron microscopy identified relatively increased numbers of alpha- and delta-cells within the atrophic islets 6 and 12 months after streptozotocin injections. Plasma glucose, plasma immunoreactive insulin, and extractable pancreatic immunoreactive insulin measurements documented the persistence of profound hyperglycemia, as well as the reduction of plasma and pancreatic immunoreactive insulin levels. Immunofluorescence studies demonstrated the absence of circulating islet cell antibodies during both the acute and chronic stages of the syndrome. The pathogenesis of this model of insulin-deficient diabetes is believed to be a cell-mediated autoimmune reaction directed against pancreatic beta-cells altered by subdiabetogenic injections of streptozotocin. The importance of the increased number of type C viruses within surviving beta-cells remains obscure.

Angiography in the diagnosis of renal allograft dysfunction

We reviewed retrospectively 75 renal transplant arteriograms done during a 7-year period. Acute rejection and vasomotor nephropathy were not differentiated. Generalized cortical ischemia was diagnosed correctly in 23 of 30 cases but there were 7 falsely negative results. Renal artery stenosis was found in 7 of 17 cases in which the main indication for arteriography was hypertension. We conclude that the major role of transplant arteriography is in the diagnosis of larger vessel disease.

The evolution of sexual reproduction as a repair mechanism. Part II. Mathematical treatment of the wheel model and its significance for real systems

The dynamics of populations of self-replicating, hierarchically structured individuals, exposed to accidents which destroy their sub-units, is analyzed mathematically, specifically with regard to the roles of redundancy and sexual repair. The following points emerge from this analysis: 1. A population of individuals with redundant sub-structure has no intrinsic steady-state point; it tends to either zero or infinity depending on a critical accident rate alpha c. 2. Increased redundancy renders populations less accident prone initially, but population decline is steeper if alpha is greater than a fixed value alpha d. 3. Periodic, sexual repair at system-specific intervals prevents continuous decline and stabilizes the population insofar as it will now oscillate between two fixed population levels. 4. The stabilizing sexual interval increases with increased complexity provided this is accompanied by appropriate levels of redundancy. 5. The model closely simulates the dynamics of heterosis effects. 6. Repair fitness is a population fitness: the chance of an individual being repaired is a function of the statistical make-up of the population as a whole at the particular period. Populations living at alpha greater than alpha c either engage in sexual repair at the appropriate time or they die out. 7. The mathematical properties of the model illustrate mechanisms which possibly played a role in the evolution of a mortal soma in relation to sexual reproduction.

Genetic influence of the streptozotocin-induced insulitis and hyperglycemia

Multiple injections of subdiabetogenic doses of streptozotocin (SZ) to CD-1 male mice produce a diabetic syndrome that includes a cell-mediated immune reaction against the pancreatic islet. The importance of the host genetic background in the pathogenesis of this model of diabetes was studied by comparing various inbred strains of mice. Of eight strains of mice studied, only C57BL/KsJ developed insulitis and hyperglycemia comparable to that observed in CD-1 mice. In two mouse strains (DBA/J and BALB/cJ) having an H-2d haplotype similar to the C57BL/KsJ, only mild insulitis and glucose intolerance were observed. These data suggest that major histocompatibility complex genes, as presently defined, cannot be the only determinant of the severity of hyperglycemia and insulitis in this model.

Passive enhancement of rat renal allografts by antibodies to a non-SD (Ag-B) locus analogous to Ia and demonstration of linkage to the MHC

The rat MHC contains a distinct locus for Ia-like antigens. The alleles of this locus are not always associated with like alleles of the MLR and Ag-B (SD) loci in inbred strains. This is demonstrated by the Fischer strain, which is MLR and tag-B (SD) 1 (H-11) but shares an Ia specificity with BN (Ag-B3, H-1n). The biologic significance of anti-Ia is distinctive, having in vivo graft-enhancing capability, even when it is cross-reacting (i.e., Lew anti-Fi enhances BN). In contrast, anti-AG-B (SD) does not enhance in the rat model.

Specific and nonspecific antitumor immunity. III. Specific T lymphocyte-mediated cytolysis of P815 mastocytoma and SL2 lymphoma by draining lymph node cells from syngeneic tumor-bearing DBA/2J mice

Tumor-specific cytolytic activity, as measured by the 51Cr release assay, has been demonstrated in the draining lymph node cells from DBA/2 mice bearing the syngeneic P815 mastocytoma or SL2 lymphoma. This lytic activity is mediated by cytolytic T lymphocytes (CTL), since cytotoxicity is eliminated by treatment of the effector cells with anti-Thy 1.2 (theta) serum plus complement but is enhanced or unaffected by anti-Thy 1.2 serum alone, antimouse immunoglobulin plus complement, normal or aggregated mouse immunoglobulin, or removal of adherent cells. The time course of the CTL response has been analyzed and is similar for both P815 and SL2, with a peak around Days 10 to 12 after tumor grafting. Detectable CTL activity then wanes despite continued antigenic stimulation from the growing tumor. The ability of the immunotherapeutic agent Corynebacterium parvum to augment such specific CTL responses is documented as one antitumor pathway by which this agent may act.

The evolution of the cooperative group

A simple model, illustrating the transition from a population of free swimming, solitary cells (Chlamydomonas-type) to one consisting of small colonies (Gonium-type) serves as a basis to discuss the evolution of the cooperative group. The transition is the result of a mutation of the dynamics of cell division, delayed cell separation leads to colonies of four cells. With this mutation cooperative features appear, such as synchronised cell divisions within colonies and coordinated flagellar function which enables the colony to swim in definite directions. The selective advantages under given, environmental conditions are defined and the periods necessary for complete allelic replacement in small populations are calculated for asexual and sexual reproduction. The assumption of a steady-state population during allelic substitution is critically considered, particularly under conditions of competition. It is shown that density-dependent population control must operate in the process of selection, Sexual reproduction slows down the rate of selection even though all cells are haploid. This phenomenon can be explained in general terms of "organizational dominance', where individual units coordinate the function of their neighbours which may be of a different allelotype. Cooperativity is pointed out as an a priori systemic feature which resides in the sub-units of systems, group formation and coordination appears thus as an almost inevitable event. A particular type of system described as 'closed cycle of positive fitness interaction' is discussed in more detail. It has the remarkable feature that its members cannot compete with each other; selection takes place between whole cycles (in analogy to Eigen's 1971 model). Gonium has a wide spectrum of 'somatic plasticity' which enables it to assume various colonial configurations depending on physiological and environmental conditions. This feature can be explained as the result of dynamic flexibilities on the macro-molecular level. The particular relationship between the vast, molecular complexity and the relative simple dynamics of the cell cycle must lead eventually to the genetic fixation of an environmentally induced phenotype.

Language behaviour in acute and chronic schizophrenia

A predicition made by Broen (1968) regarding the performance of acute and chronic non-paranoid schizophrenics on measures of dominant verbal response bias was tested in a group of 40 hospitalized schizophrenic patients. A subgroup of 10 chronic patients were found to show an abnormal dominant response bias on two different language tasks and on one task showed a bias significantly greater than that shown by a group of 10 acute patients matched on verbal IQ and rated symptomatology. A correlational analysis of the bias scores of the total sample in relation to three indices of chronicity also showed a trend in the predicted direction of a greater dominant response bias with increasing chronicity. The data are consistent with Broen's (1968) theory of dominant response bias as a learned defence against aversive response interference in acute schizophrenia.