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PubMed1993

The expression of the complement regulators CD46, CD55, and CD59 by human sperm does not protect them from antisperm antibody- and complement-mediated immune injury.

OBJECTIVES: To investigate whether membrane-bound regulators of the initial (C3) and terminal (C5b-9) complement (C) pathway components are expressed on human sperm and to evaluate the protective effects of these regulators in restricting antisperm antibody and C-mediated injury. DESIGN: Sperm surface C inhibitors were quantitated by indirect immunofluorescence flow cytometry using murine monoclonal antibodies to detect C3 regulatory proteins, C3b/C4b receptor type (CR1, CD35), membrane cofactor protein (CD46), and decay-accelerating factor (CD55), and C5b-9 inhibitor, P18 (CD59) on acrosome-intact human sperm and sperm induced to undergo acrosomal loss. The susceptibility of sperm to antisperm antibody- and C-mediated immobilization was evaluated by sperm motility loss in the presence of antidecay-accelerating factor and/or anti-P18. SETTING: University of Oklahoma Health Sciences Center, a tertiary care referral center. RESULTS: Both decay-accelerating factor and P18 were detected on acrosome-intact and sperm induced to undergo acrosomal loss; neither expressed CR1. Membrane cofactor protein was detected on only acrosome-reacted sperm. The time course of sperm motility loss in antisperm antibody-negative sera in the presence of antidecay-accelerating factor, anti-P18, or both had a cumulative effect and brought about a time-dependent enhancement of sperm motility loss by serum C. However, sperm motility loss in C-fixing antisperm antibody-positive sera was unaffected by sperm membrane bound C3 and C5b-9 regulators. CONCLUSIONS: The susceptibility of human sperm to antisperm antibody- and C-induced motility loss may reflect a low potency of the sperm membrane C regulators membrane cofactor protein, decay-accelerating factor, and P18 in inhibiting serum C. Therefore, the use of serum C in the traditional assay for the diagnosis of cytotoxic antisperm antibody in infertile couples may have limitations. The inefficiency of these proteins in restricting serum C activity also suggested a secondary function in restricting localized proteolytic damage at the site of fertilization.

Antibodies, Monoclonal↗
PubMed1993

Antigenic similarities between respiratory and reproductive tract mucins: heterogeneity of mucin expression by human endocervix and endometrium.

OBJECTIVES: To determine whether common epitopes are shared by respiratory and reproductive tract mucins and to compare the expression of cross-reactive mucin subtypes in human endocervix and endometrium. DESIGN: An immunohistochemical study of mucin expression using a panel of monoclonal and polyclonal antimucin antibodies and timed endocervical and endometrial biopsies. SETTING: University of Oklahoma Health Sciences Center, a tertiary care referral center. PATIENTS: Twenty-eight women who underwent laparoscopy, laparotomy, or hysterectomy. MAIN OUTCOME MEASURES: The expression of human tracheal mucin subspecies (types I to V) in endocervix (n = 3) and endometria (n = 25). RESULTS: Of the five mucin subspecies, type I mucin was localized to the squamous epithelium of endocervix and both glands and stroma of endometrium. Both tissues failed to react with type II mucin. Type III mucin was localized to differentiated cells of the squamous epithelium of endocervix and the glandular endometrium. Type IV mucin was specific to endometrium and was localized both in endometrial glands and stroma with no reactivity with endocervix. Type V mucin was expressed in both cervical and endometrial stroma and glands. CONCLUSIONS: Human respiratory and reproductive tract mucins share common peptide and carbohydrate epitopes. Human endocervix and endometria express a unique pattern of mucin antigens. Because of their restricted specificity, these monoclonal antibodies could provide new tools to investigate normal and aberrant expression of reproductive tract mucin subtypes in tissues and secretions.

Adult↗
PubMed1996

Antigenic cross-reactivity of human tracheal mucin with human sperm and trophoblasts correlates with the expression of mucin 8 gene messenger ribonucleic acid in reproductive tract tissues.

OBJECTIVE: To test whether autoimmunity to sperm in men with cystic fibrosis (CF) is a result of cross-reactivity between sperm and carbohydrate sequences of the abnormal CF mucins, we investigated the possible epitope sharing between sperm surface antigens and CF mucin antigens using specific monoclonal antibodies (mAbs) directed to purified CF tracheobronchial mucin-1 (HTM-1) and the expression of tracheal mucin 8 gene (MUC8) mRNA in normal male and female reproductive tract tissues by Northern blot analysis. DESIGN: A panel of mAbs directed to HTM-1 subspecies (types I to V) and polyclonal antibodies (pAb) to native and deglycosylated HTM-1 were tested for their ability to agglutinate motile sperm. An indirect immunofluorescence assay was used to detect expression of cross-reactive HTM-1 epitopes on sperm, term placenta (n = 3), and purified trophoblasts (n = 9). Northern blot analysis was used to detect MUC8 messenger RNA (mRNA) in male and female reproductive tract tissues. SETTING: University of Oklahoma Health Sciences Center, a tertiary care referral center. MAIN OUTCOME MEASURES: The demonstration of cross-reactive mucin at the protein and mRNA levels in reproductive tract tissues. RESULTS: Of the five mucin subspecies, type II, IV, and V mucin-specific mAbs (21.3, 33.3, and 54.1) induced head-to-head agglutination of motile sperm; pAb to deglycosylated mucin had no effect. Sperm agglutination mediated by type IV mucin mAb 33.3 was abrogated completely by D-mannose. Within the term placental villi, type II mucin, was localized to fetal endothelium, type IV mucin was localized to syncytiotrophoblast, and type V mucin was localized to cytotrophoblasts. Immunologic studies correlated with the results of Northern blot analysis, which revealed strong MUC8 mRNA expression in the human testis, placenta, endometrium, and cervix and weak or undetectable levels in the human epididymis, seminal vesicle, ovary, fallopian tube, and uterus. CONCLUSIONS: Both male and female reproductive tract tissues synthesize tracheal MUC8 mucin. Monoclonal antibodies specific to human tracheal mucin subtypes induced "immune-type" agglutination of motile sperm. Therefore, expression of cross-reactive MUC8 mucin epitopes in reproductive tract tissues may contribute to the development of low affinity, carbohydrate-specific, agglutinating antisperm antibodies in the genital tract.

Antibodies, Monoclonal↗
PubMed2001

Differential adhesion of major surface proteins 1a and 1b of the ehrlichial cattle pathogen Anaplasma marginale to bovine erythrocytes and tick cells.

Anaplasma marginale is a tick-borne ehrlichial pathogen of cattle for which six major surface proteins (MSPs) have been described. The MSP1 complex, a heterodimer composed of MSP1a and MSP1b, was shown to induce a protective immune response in cattle and both proteins have been identified as putative adhesins for bovine erythrocytes. In this study the role of MSP1a and MSP1b as adhesins for bovine erythrocytes and tick cells was defined. msp1alpha and msp1beta1 genes from the Oklahoma isolate of A. marginale were cloned and expressed in Escherichia coli K-12 under the control of endogenous and tac promoters for both low and high level protein expression. Expression of the recombinant polypeptides was confirmed and localised on the surface of transformed E. coli. The adhesion properties of MSP1a and MSP1b were determined by allowing recombinant E. coli expressing these surface polypetides to react with bovine erythrocytes, Dermacentor variabilis gut cells and cultured tick cells derived from embryonic Ixodes scapularis. Adhesion of the recombinant E. coli to the three cell types was determined using recovery adhesion and microtiter haemagglutination assays, and by light and electron microscopy. MSP1a was shown by all methods tested to be an adhesin for bovine erythrocytes and both native and cultured tick cells. In contrast, recombinant E. coli expressing MSP1b adhered only to bovine erythrocytes and not to tick cells. When low expression vectors were used, single E. coli expressing MSP1a was seen adhered to individual tick cells while reaction of tick cells with the E. coli/MSP1a/high expression vector resulted in adhesion of multiple bacteria per cell. With electron microscopy, fusion of E. coli cell membranes expressing MSP1a or MSP1b with erythrocyte membranes was observed, as well as fusion of tick cell membranes with E. coli membranes expressing MSP1a. These studies demonstrated differential adhesion for MSP1a and MSP1b for which MSP1a is an A. marginale adhesin for both bovine erythrocytes and tick cells while MSP1b is an adhesin only for bovine erythrocytes. The role of the MSP1 complex, therefore, appears to vary among vertebrate and invertebrate hosts.

Adhesins, Bacterial↗
PubMed2001

A novel TC deletion resulting in Pro(260)-->Stop in the human LCAT gene is associated with a dominant effect on HDL-cholesterol.

Human lecithin:cholesterol acyltransferase (LCAT) plays a key role in the biogenesis of circulating high-density lipoprotein-cholesterol (HDL-C) and reverse cholesterol efflux. We investigated the molecular defect in the LCAT gene in a family with low levels of HDL-C. The proband, a 53-year-old woman from Oklahoma City, had a HDL-C level of 0.21 mmol/l. The LCAT activity in the proband was 5 nmol/ml/h and cholesterol esterification rate was 54.2 nmol/ml/h, consistent with LCAT deficiency. Analysis of polymerase chain reaction (PCR) amplified subgenomic fragments of LCAT DNA on polyacrylamide gels revealed heteroduplex bands in the proband and three other affected individuals in exon 6. DNA sequence analyses of the proband's LCAT gene identified a 2 base pair deletion (TC) (base pairs 4544-4545, corresponding to amino acid 255) in the heteroduplex allele, thereby converting Pro(260) to a premature stop codon and a predicted truncated protein of 260 amino acids. This is approximately 60% of the length of the normal translated protein. The heterozygous individuals also revealed significant reduction in apolipoprotein A-1 levels compared with the unaffected family members (n=4). The marked reduction in HDL-C in the proband and sibling suggests a dominant effect of this mutation on HDL-C levels. Furthermore, because the deletion results in a heterozygous allele that can be detected by a simple PCR reaction and polyacrylamide gel-size fractionation, it may be possible to rapidly screen susceptible individuals for the presence of this mutation.

Base Sequence↗
PubMed1990

Improvement in catheter sepsis rate in burned children.

Routine frequent central venous catheter (CVC) changes in burned patients (either change in insertion site or change over guidewires) has been advocated to decrease catheter-related sepsis. The need for this management has not been verified for children with burns. We reviewed our pediatric burn population with regard to CVC sepsis rate and individual CVC longevity to confirm this traditional policy. From 1978 to 1988, 70 children admitted to the Children's Hospital of Oklahoma Burn Unit required central venous access. Patients in whom CVCs were changed frequently (FC), (n = 10; no. of CVC, 46) were compared with those in whom CVCs were changed only for mechanical complications or sepsis (NFC), (n = 60; no. of CVC, 74). There were 10 septic CVCs in each group. The difference in mean length of individual CVC use between FC and NFC was significant (4.6 v 17.7 days; P less than .01). The difference in the number of septic CVCs per total number of catheter days in each group was highly significant (FC: 10 CVC/212 d. = 0.05; NFC: 10 CVC/1,112 d = 0.009; P less than .001). This study demonstrates a significant decrease in catheter-related sepsis when CVCs are not changed on a routine frequent basis.

Bacterial Infections↗
PubMed1996

End-tidal carbon dioxide for monitoring primary closure of gastroschisis.

Previous criteria for primary reduction of the herniated viscera in newborn infants with gastroschisis included intraoperative respiratory rate, cardiac indices, degree of viscero-abdominal disproportion, size of defect, and lower extremity turgor. From 1976 through 1993, 129 neonates with gastroschisis were treated at Children's Hospital of Oklahoma. Intraoperative end-tidal carbon dioxide (ETCO2) monitoring was standard therapy beginning in 1985. The authors evaluated the effect of abdominal closure on ETCO2 to determine if there was a particular ETCO2 level at which closure was not feasible. There was no difference in overall mortality, birth weight, or postoperative ventilation requirements between children who had closure before 1985 (ie, without ETCO2 monitoring) and those who had repair after 1985. However, more cases in the 1985-1993 group had primary closure, and none of these required conversion to a staged procedure. An ETCO2 of > or = 50 suggests that primary closure may be unsafe. These data suggest that infants with gastroschisis can have primary closure based on intraoperative ETCO2 monitoring; no additional invasive monitoring would be necessary to assess closure.

Abdominal Muscles↗
PubMed2001

Isolation and characterisation of five neurotoxic and cardiotoxic polypeptides from the sea anemone Anthopleura elegantissima.

Five toxins (APE 1 to APE 5) of the sea anemone species Anthopleura elegantissima (Brandt) have been isolated from a toxic by-product fraction of its concentrated crude watery-methanolic extract, prepared previously for the isolation of a neuropeptide (the head-activator) by Schaller and Bodenmüller (Proc. Natl. Acad. Sci. USA 78 (1981) 7000) from 200kg sea anemones. Toxin purification was performed by desalting of the starting material by dialysis (MWCO 3500) against distilled water, anion exchange chromatography on QAE-Sephadex A25 at pH 8, twice gel filtration on Sephadex G50 m, repeated chromatography on QAE-Sephadex at pH 10 and chromatography on the cation exchanger Fractogel EMD SO(3)(-)-650 M.Final purification of the toxins was achieved by HPLC on MN SP 250/10 Nucleosil 500-5 C(18) PPN and MN SP 250/21 Nucleosil 300-7 C(18). Each toxin was composed of at least two isotoxins of which APE 1-1, APE 1-2, APE 2-1, APE 2-2 and APE 5-3 were isolated in preparative scale. With exception of APE 5-3 the sequences of the isotoxins have been elucidated. They resemble the 47 residue type-I long polypeptide toxins native to Anemonia sulcata (Pennant). All isotoxins paralyse the shore crab (Carcinus maenas) by tetanic contractions after i.m. application. The toxins modify current passing through the fast Na(+) channel in neuroblastoma cells, leading to delayed and incomplete inactivation. APE 1-1, APE 2-1 and APE 5-3 produce a positive inotropic effect in mammalian heart muscle, although they differ in potency. The order of potency is APE 2-1>APE 1-1>APE 5-3 (i.e. threshold concentrations are 1, 10 and 300nM, respectively). In addition, they enhance the spontaneous beating frequency in isolated right atria (guinea pig). The most potent cardiotoxic isotoxin is APE 2-1, its sequence is identical with that of AP-C, a toxin isolated and characterised previously by Norton et al. (Drugs and Foods from the Sea, 1978, University of Oklahoma Press, p. 37-50).LD50 APE 2-1:1 micro g/kg b.w. C. maenas (i.m.). LD50 APE 1-1:10 microg/kg b.w. C. maenas (i. m.). LD50 APE 5-3:50 microg/kg b.w. C. maenas (i.m.).

Animals↗
PubMed1988

Microbial ecology of the terrestrial subsurface.

We have presented a current view of the microbial ecology of the terrestrial subsurface by considering primarily the ecology of shallow aquifer sediments. The properties of the aquifer sediments and groundwater determine their ability to support microbial life and control the abundance and activities of microorganisms. Pore size, nutrient limitations, availability of electron acceptors, and large surface area for attachment all may have major effects on microbial abundance and activities in aquifer material. Microorganisms are the predominant forms of life in the subsurface. They will be found wherever enough space, nutrients, and water are available for them to live. Environmental factors such as pH, temperature, hydrostatic pressure, and dissolved salts also may influence subsurface microbial populations, but these factors do not exhibit great extremes in shallow water table aquifers, and thus only in very deep formations might they limit diversity or preclude the existence of microorganisms. Although the presence and activity of microorganisms in most subsurface environments are predictable, only recently have subsurface microbial populations in shallow subsurface zones been characterized. Aseptic sampling methods have been employed and microbiological and biochemical methods have been adapted to determine the types, abundance, and metabolic activities of microorganisms in subsurface material. Bacteria dominate, but eukaryotic microorganisms also are present. Vertical profile studies of a shallow aquifer in Oklahoma showed that active microbial biomass declined with depth to the unsaturated zone, but was variable in saturated sediments. Such a distribution of active biomass may be common in shallow aquifers. Studies on the lateral distribution of microorganisms in shallow and deep aquifers suggest that microorganisms are transported or migrate over fairly long distances in aquifer sediments. Surficial aquifers may be colonized by vertical or lateral transport and migration of surface microorganisms from recharge areas, but microorganisms could also have colonized when sediments were originally deposited. The biological and physical mechanisms controlling the migration of microorganisms in aquifers are not well understood. The function of shallow aquifers was considered with regard to nutritional ecology. Most pristine aquifers are oligotrophic. Heterotrophic life in these unique ecosystems is supported by secondary organic compounds that filter down from the soil above. The quantity and quality of organic nutrients depend on the age of water and rate of recharge of the aquifer.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacteria↗
PubMed2003

Escherichia coli O157 in feedlot cattle feces and water in four major feeder-cattle states in the USA.

The prevalence of Escherichia coli O157 was determined in 10662 fecal samples, 2130 water and 1132 water tank-sediment samples collected during the summer months in 2001 from 711 pens in 73 feedlots located in Kansas, Nebraska, Texas, or Oklahoma, USA. Overall, 10.2% of fecal samples were positive for E. coli O157, with 52% of the pens and 95.9% of the feedlots having at least one positive fecal sample. There were no differences among states or months in the fecal prevalences. Water or water tank-sediment was positive in 13.1% of the water tanks, and 60.3% of feedlots had at least one positive tank. Cattle were more likely to be shedding E. coli O157 in pens with positive water tanks, and water was more likely to be positive when E. coli O157 was detected in the sediment.

Animals↗
PubMed1987

Congenital pigmented and vascular lesions in newborn infants.

The incidence of congenital cutaneous lesions was ascertained by a single dermatologist in each of 830 sequential newborn infants over a 3-month period at the Oklahoma Teaching Hospitals. Lesions were observed in 57% of infants (77% of blacks and 49% of nonblacks). Vascular lesions were the most frequent, occurring in 44% of neonates. Pigmented lesions other than mongolian spots were observed in 15.8% of blacks and in 1.6% of whites. Clinical criteria do not readily distinguish nevus cell nevi from other pigmented lesions. Wood's light examination did not enhance the identification of congenital lesions. Inadequate examination of infants and marked underreporting of congenital lesions in newborn infants are widespread.

Black People↗
PubMed1999

Emergency physicians and biological terrorism.

Recent developments, such as the bombings of the World Trade Center in 1993 and the Alfred P. Murrah Federal Building in Oklahoma City in 1995, the sarin attacks in Tokyo and Matsumoto, Japan, and US Embassy bombings in Kenya and Tanzania in 1998, have heightened fears of terrorist attacks. Future terrorist activities will continue to involve bombs and firearms, but may also include weapons of mass destruction, including biological agents. Recent US government initiatives have recognized the threats to our country from these weapons and have funded planning and response programs. These preparedness programs are being built on existing infrastructure of EMS and fire services' plans for hazardous materials response. Appropriate emergency department and hospital response, guided by public health principles, could significantly limit the morbidity and mortality of biological warfare agents. Inappropriate response by the medical community may worsen a chaotic and potentially devastating situation. This article discusses planning and response issues central to a potential bioterrorism event.

Biological Warfare↗
PubMed2000

Hepatitis B school-based vaccination programmes in the USA: a model for hepatitis A and B.

Following the recommendation for routine vaccination against hepatitis B virus for newborns, many states have started school-based catch-up vaccination of 11- to 12-year-olds. Implementation of these programmes requires educational and promotional initiatives to increase awareness among parents, children, teachers, school nurses, school boards and administration. Experience in Framingham, Massachusetts, suggests that over 90% of targeted hepatitis B vaccine coverage can be achieved. Because hepatitis B vaccination targeted at high-risk groups in the USA was largely unsuccessful, this suggests that the initial similar targeted approach with hepatitis A vaccination will also fail. Only about 50% of hepatitis A cases have a known risk factor, and multiple high-risk areas exist throughout the USA. However, the geographical clustering of these high-risk areas and the occurrence of periodic outbreaks, suggest that school-based hepatitis A vaccination programmes may be effective in reducing the risk of infection. A voluntary programme in San Antonio achieved 43% of the targeted coverage in its first year, and a compulsory programme is due to start in Oklahoma. The effectiveness of this programme is not yet known, but future recommendations are likely to include hepatitis A vaccination as a school entry requirement in areas with high incidence of hepatitis A.

Child↗
PubMed2001

Efficacy of histopathology in detecting petrochemical-induced toxicity in wild cotton rats (Sigmodon hispidus).

A variety of chemical mixtures exist in the soil of petrochemical waste sites, and many of these compounds are known immunotoxicants that have been observed to induce immune alterations in wild rodents inhabiting many of these petrochemical waste sites. Conventional histopathological assessments have been widely used with considerable success to investigate immunotoxicity of various agents under laboratory conditions. We hypothesized that histopathologic assessments would be equally sensitive for detecting exposure to complex mixtures of toxicants in cotton rats (Sigmodon hispidus) residing in contaminated habitats. Histopathological parameters were examined from a total of 624 cotton rats that were seasonally collected from 13 petrochemical-contaminated waste sites and 13 ecologically matched reference sites in Oklahoma over a 3-year period. Histopathological examination did not reveal any lesion associated with exposure to petrochemical wastes except renal inclusion bodies. Prevalence and severity of histologic lesions in liver and kidneys of cotton rats were significantly influenced by season, where prevalence and severity were lower in winter than summer on all study sites. These results suggest that the evaluation of toxicity from exposure to contaminants in the soil of industrial waste sites using histopathological assessments is not sensitive enough to detect exposure to the low levels of environmental contaminants present on most waste sites.

Animals↗
PubMed2002

Modeling above-canopy CO2 flux and evapotranspiration in wheat.

Simulations of above-canopy water vapor and CO2 fluxes were calculated by the USGF linked model of canopy gas exchange and subsurface processes for the 1996-1997 winter wheat season at the AmeriFlux Wheat Site, Oklahoma. Soil surface CO2 flux plus canopy gas exchange and transpiration plus soil evaporation modeled the CO2 and water vapor fluxes, respectively. Parameter values for net photosynthesis, respiration and transpiration were obtained from published sources, generated from Wheat Site data, or estimated by minimizing standard deviation between model and data. The mean measured downward flux of CO2 during rapid growth and maturity of the crop was -0.45 mg m(-2) s(-1) compared to simulated flux of -0.47. Simulated downward CO2 flux exceeded measured values during rapid growth of the crop but underestimated the flux during maturity. For the entire 285-day period, the mean measured upward CO2 flux at night was 0.06 and simulated flux was 0.05.

Carbon Dioxide↗
PubMed2002

Escherichia coli and total coliforms in water and sediments at lake marinas.

Escherichia coli, a fecal coliform, and total coliforms were monitored between September 1999 and October 2001 in five marinas at Lake Texoma, located on the Oklahoma and Texas border. The general trend was that densities of E. coli were lower in the summer season due to the lower loading of fecal material into Lake Texoma and the ecological conditions of the lake, such as more vigorous grazing by protozoa and less viability of E. coli at an elevated temperature. The densities of total coliforms greatly increased in the summer. E. coli levels increased with depth, and the bottom water samples had higher densities of E. coli mainly due to their association with particles. There was a direct relationship between amount of gasoline sold, which was related to recreational boating activity, and the resuspension of E. coli. This indicated that recreational boating activity in lake marinas may have resuspended bottom sediments with bound E. coli, and the presence of E. coli in marinas was not an indication of recent fecal contamination. E. coli were detected in the largest densities at the boat dock points, followed by the gasoline filling station, and marina entrance. In addition, enumeration of bacteria in bottom sediment showed that the densities of E. coli and total coliforms in sediment were much higher compared to those in lake water.

Enterobacteriaceae↗
PubMed2000

Ecotoxicity revealed in parasite communities of Sigmodon hispidus in terrestrial environments contaminated with petrochemicals.

Several studies have documented contaminant-induced alterations in host-parasite relationships of vertebrate hosts in aquatic environments, suggesting this functional relationship may be useful for monitoring community-level effects of stressors in terrestrial systems. We hypothesized that gastrointestinal helminth communities of hispid cotton rat (Sigmodon hispidus) hosts would be sensitive to exposure to complex mixtures of petrochemicals in soils of tallgrass prairie habitats contaminated with oil refinery wastes. Parasite communities were surveyed (1993-95) on three contaminated and two reference sites on an oil refinery complex in Oklahoma. Abundance of Schizotaenia sigmodontis infections was two-fold higher in hosts from reference than contaminated sites. Strongyloides sigmodontis exhibited pronounced seasonal differences in prevalence and abundance in host populations from reference sites, with much higher seasonal variation compared to hosts from contaminated sites. Other helminth species, including Schizotaenia sigmodontis, Protospirura muris, Longistriata adunca, also exhibited seasonal fluctuations in abundance. Differences in species richness and composition were also observed, with hosts from the reference sites consistently supporting a higher mean number of species compared to those from contaminated sites. Differences in community structure indicate that host-parasite relationships can provide another useful method for monitoring community-level impacts of contamination in a terrestrial system.

Journal Article↗
PubMed2003

Antibodies to Anaplasma marginale major surface proteins 1a and 1b inhibit infectivity for cultured tick cells.

Major surface protein 1 (MSP1) of the cattle pathogen Anaplasma marginale (Rickettsiales: Anaplasmataceae) is a complex of two proteins, MSP1a and MSP1b. Previous studies demonstrated that MSP1a and MSP1b are adhesins for bovine erythrocytes, while only MSP1a proved to be an adhesin for tick cells. In this study, a tick cell culture system for propagation of A. marginale was used to develop an infection inhibition assay for testing the ability of antisera to block infection of A. marginale for cultured tick cells. A. marginale derived from cell culture was incubated with various antisera prior to inoculation onto cell monolayers. The monolayers were harvested 7 days post-inoculation and A. marginale in the cultures was quantified using an antigen detection ELISA. Antisera tested in the infection inhibition assay were derived from persistently infected cattle, from cattle immunized with A. marginale purified from bovine erythrocytes, and from rabbits and cattle that were immunized with the recombinant MSP1a, MSP1b and MSP1 complex. Antibodies from cattle persistently infected with A. marginale, cattle immunized with A. marginale from bovine erythrocytes or cattle immunized with the recombinant MSP1 complex did not inhibit the infectivity of A. marginale for tick cells. Antiserum from rabbits immunized with MSP1a and MSP1b (individually or combined) reduced infection of both the Virginia and Oklahoma isolates of A. marginale for tick cells by 25-70%. Likewise, antisera from cattle immunized with recombinant MSP1a or MSP1b inhibited infection of tick cells by 26-37%. These results further confirm the role of MSP1 complex proteins in infection of tick cells. Lack of inhibition of infection by antisera from naturally infected cattle or cattle immunized with whole organisms suggests that the bovine immune response is not directed toward blocking infection of A. marginale for tick cells and may contribute to the continued infectivity of the pathogen for ticks.

Anaplasma↗