Increased occurrence of the rare golden color morph of Pacific chub Kyphosus sandwicensis in a no-take marine reserve

Pacific chub, Kyphosus sandwicensis, are typically gray but some individuals display a golden color morph. We estimated that the frequency of occurrence of the golden morphs increased significantly from 2007 (1.9%) and 2012 (2.6%) to 2017 (5.0%) inside a no-take marine reserve around Nihoa Island in the Northwestern Hawaiian Islands. While sporadic observations of a golden color morph have been noted for several other marine fish species, we provide a quantitative estimate of changes in the frequency of occurrence of the morph within a wild marine population.

No butts about it: using urogenital disparity in a deep-water snapper, Etelis carbunculus (Lutjanidae), for field-based sexual identification

In this study, the authors describe a process that consistently identified sex based on differences in the length and characteristics of the urogenital papilla septum of Etelis carbunculus, a deep-water snapper (Lutjanidae, Etelinae). These characteristics, regardless of fish size, were found to be accurate for 96% of 157 specimens evaluated. The application of this external sex determination technique expedites the collection of sex-specific data and may perform well for other morphologically similar lutjanid snappers. The non-invasive method also minimizes damage to the fish, thereby allowing either its return to the ocean or landing as a valuable whole fish.

Over half of known human pathogenic diseases can be aggravated by climate change

It is relatively well accepted that climate change can affect human pathogenic diseases; however, the full extent of this risk remains poorly quantified. Here we carried out a systematic search for empirical examples about the impacts of ten climatic hazards sensitive to greenhouse gas (GHG) emissions on each known human pathogenic disease. We found that 58% (that is, 218 out of 375) of infectious diseases confronted by humanity worldwide have been at some point aggravated by climatic hazards; 16% were at times diminished. Empirical cases revealed 1,006 unique pathways in which climatic hazards, via different transmission types, led to pathogenic diseases. The human pathogenic diseases and transmission pathways aggravated by climatic hazards are too numerous for comprehensive societal adaptations, highlighting the urgent need to work at the source of the problem: reducing GHG emissions.

The implementation of rare events logistic regression to predict the distribution of mesophotic hard corals across the main Hawaiian Islands

Predictive habitat suitability models are powerful tools for cost-effective, statistically robust assessment of the environmental drivers of species distributions. The aim of this study was to develop predictive habitat suitability models for two genera of scleractinian corals (Leptoserisand Montipora) found within the mesophotic zone across the main Hawaiian Islands. The mesophotic zone (30–180 m) is challenging to reach, and therefore historically understudied, because it falls between the maximum limit of SCUBA divers and the minimum typical working depth of submersible vehicles. Here, we implement a logistic regression with rare events corrections to account for the scarcity of presence observations within the dataset. These corrections reduced the coefficient error and improved overall prediction success (73.6% and 74.3%) for both original regression models. The final models included depth, rugosity, slope, mean current velocity, and wave height as the best environmental covariates for predicting the occurrence of the two genera in the mesophotic zone. Using an objectively selected theta (“presence”) threshold, the predicted presence probability values (average of 0.051 for Leptoseris and 0.040 for Montipora) were translated to spatially-explicit habitat suitability maps of the main Hawaiian Islands at 25 m grid cell resolution. Our maps are the first of their kind to use extant presence and absence data to examine the habitat preferences of these two dominant mesophotic coral genera across Hawai‘i.

Temporal and spatial trends in prey composition of wahoo Acanthocybium solandri: a diet analysis from the central North Pacific Ocean using visual and DNA bar-coding techniques

A diet analysis was conducted on 444 wahoo Acanthocybium solandri caught in the central North Pacific Ocean longline fishery and a nearshore troll fishery surrounding the Hawaiian Islands from June to December 2014. In addition to traditional observational methods of stomach contents, a DNA bar-coding approach was integrated into the analysis by sequencing the cytochrome c oxidase subunit 1 (COI) region of the mtDNA genome to taxonomically identify individual prey items that could not be classified visually to species. For nearshore-caught A. solandri, juvenile pre-settlement reef fish species from various families dominated the prey composition during the summer months, followed primarily by Carangidae in autumn months. Gempylidae, Echeneidae and Scombridae were dominant prey taxa from the offshore fishery. Molidae was a common prey family found in stomachs collected north-east of the Hawaiian Archipelago while tetraodontiform reef fishes, known to have extended pelagic stages, were prominent prey items south-west of the Hawaiian Islands. The diet composition of A. solandri was indicative of an adaptive feeder and thus revealed dominant geographic and seasonal abundances of certain taxa from various ecosystems in the marine environment. The addition of molecular bar-coding to the traditional visual method of prey identifications allowed for a more comprehensive range of the prey field of A. solandri to be identified and should be used as a standard component in future diet studies.

The Coral Trait Database, a curated database of trait information for coral species from the global oceans

Trait-based approaches advance ecological and evolutionary research because traits provide a strong link to an organism's function and fitness. Trait-based research might lead to a deeper understanding of the functions of, and services provided by, ecosystems, thereby improving management, which is vital in the current era of rapid environmental change. Coral reef scientists have long collected trait data for corals; however, these are difficult to access and often under-utilized in addressing large-scale questions. We present the Coral Trait Database initiative that aims to bring together physiological, morphological, ecological, phylogenetic and biogeographic trait information into a single repository. The database houses species- and individual-level data from published field and experimental studies alongside contextual data that provide important framing for analyses. In this data descriptor, we release data for 56 traits for 1547 species, and present a collaborative platform on which other trait data are being actively federated. Our overall goal is for the Coral Trait Database to become an open-source, community-led data clearinghouse that accelerates coral reef research.

Persistence and change in community composition of reef corals through present, past, and future climates

The reduction in coral cover on many contemporary tropical reefs suggests a different set of coral community assemblages will dominate future reefs. To evaluate the capacity of reef corals to persist over various time scales, we examined coral community dynamics in contemporary, fossil, and simulated future coral reef ecosystems. Based on studies between 1987 and 2012 at two locations in the Caribbean, and between 1981 and 2013 at five locations in the Indo-Pacific, we show that many coral genera declined in abundance, some showed no change in abundance, and a few coral genera increased in abundance. Whether the abundance of a genus declined, increased, or was conserved, was independent of coral family. An analysis of fossil-reef communities in the Caribbean revealed changes in numerical dominance and relative abundances of coral genera, and demonstrated that neither dominance nor taxon was associated with persistence. As coral family was a poor predictor of performance on contemporary reefs, a trait-based, dynamic, multi-patch model was developed to explore the phenotypic basis of ecological performance in a warmer future. Sensitivity analyses revealed that upon exposure to thermal stress, thermal tolerance, growth rate, and longevity were the most important predictors of coral persistence. Together, our results underscore the high variation in the rates and direction of change in coral abundances on contemporary and fossil reefs. Given this variation, it remains possible that coral reefs will be populated by a subset of the present coral fauna in a future that is warmer than the recent past.

Symbiotic specificity, association patterns, and function determine community responses to global changes: defining critical research areas for coral-Symbiodinium symbioses

Climate change-driven stressors threaten the persistence of coral reefs worldwide. Symbiotic relationships between scleractinian corals and photosynthetic endosymbionts (genus Symbiodinium) are the foundation of reef ecosystems, and these associations are differentially impacted by stress. Here, we couple empirical data from the coral reefs of Moorea, French Polynesia, and a network theoretic modeling approach to evaluate how patterns in coral-Symbiodinium associations influence community stability under climate change. To introduce the effect of climate perturbations, we simulate local 'extinctions' that represent either the loss of coral species or the ability to engage in symbiotic interactions. Community stability is measured by determining the duration and number of species that persist through the simulated extinctions. Our results suggest that four factors greatly increase coral-Symbiodinium community stability in response to global changes: (i) the survival of generalist hosts and symbionts maximizes potential symbiotic unions; (ii) elevated symbiont diversity provides redundant or complementary symbiotic functions; (iii) compatible symbiotic assemblages create the potential for local recolonization; and (iv) the persistence of certain traits associate with symbiotic diversity and redundancy. Symbiodinium may facilitate coral persistence through novel environmental regimes, but this capacity is mediated by symbiotic specificity, association patterns, and the functional performance of the symbionts. Our model-based approach identifies general trends and testable hypotheses in coral-Symbiodinium community responses. Future studies should consider similar methods when community size and/or environmental complexity preclude experimental approaches.

Between tide and wave marks: a unifying model of physical zonation on littoral shores

The effects of tides on littoral marine habitats are so ubiquitous that shorelines are commonly described as ‘intertidal’, whereas waves are considered a secondary factor that simply modifies the intertidal habitat. However mean significant wave height exceeds tidal range at many locations worldwide. Here we construct a simple sinusoidal model of coastal water level based on both tidal range and wave height. From the patterns of emergence and submergence predicted by the model, we derive four vertical shoreline benchmarks which bracket up to three novel, spatially distinct, and physically defined zones. The (1) emergent tidal zone is characterized by tidally driven emergence in air; the (2) wave zone is characterized by constant (not periodic) wave wash; and the (3) submergent tidal zone is characterized by tidally driven submergence. The decoupling of tidally driven emergence and submergence made possible by wave action is a critical prediction of the model. On wave-dominated shores (wave height ≫ tidal range), all three zones are predicted to exist separately, but on tide-dominated shores (tidal range ≫ wave height) the wave zone is absent and the emergent and submergent tidal zones overlap substantially, forming the traditional “intertidal zone”. We conclude by incorporating time and space in the model to illustrate variability in the physical conditions and zonation on littoral shores. The wave:tide physical zonation model is a unifying framework that can facilitate our understanding of physical conditions on littoral shores whether tropical or temperate, marine or lentic.

Methods for assessment of short-term coral reef fish movements within an acoustic array

BACKGROUND

Arrays of passive receivers are a widely used tool for tracking the movements of acoustically-tagged fish in marine ecosystems; however, the spatial and temporal heterogeneity of coral reef environments pose challenges for the interpretation of tag detection data. To improve this situation for reef fishes, we introduced a novel response variable method that treats signal detections as proportions (i.e., percent transmissions detected or "detection rates") and compared this against prior approaches to examine the influence of array and transmitter performance, signal distance and environmental factors on detection rates. We applied this method to tagged snappers and groupers in the Florida reef ecosystem and controlled range-tests on static targets in Bayboro Harbor, Florida, to provide methodological guidance for the planning and evaluation of passive array studies for coral reef fishes.

RESULTS

Logistic regression analysis indicated detection rates were primarily a non-linear function of tag distance from receiver. A 'model-weighted' function was developed to incorporate the non-linear relationship between detection rate and distance to provide robust positioning estimates and allow for easy extension to tags with different ping rates.

CONCLUSIONS

Optimal acoustic array design requires balancing the interplay between receiver spacing, detection rates, and positioning error. Spacing receivers at twice the distance of the modeled 50% detection rate may be appropriate when quantification of overall space use is a priority, and would provide a minimum of 75% detection rate. However, for research where missing detections within the array is unacceptable or time-at-arrival based fine-scale positioning is needed, tighter receiver spacing may be required to maintain signal detection probability near 100%.

The distribution of the thermally tolerant symbiont lineage (Symbiodinium clade D) in corals from Hawaii: correlations with host and the history of ocean thermal stress

Spatially intimate symbioses, such as those between scleractinian corals and unicellular algae belonging to the genus Symbiodinium, can potentially adapt to changes in the environment by altering the taxonomic composition of their endosymbiont communities. We quantified the spatial relationship between the cumulative frequency of thermal stress anomalies (TSAs) and the taxonomic composition of Symbiodinium in the corals Montipora capitata, Porites lobata, and Porites compressa across the Hawaiian archipelago. Specifically, we investigated whether thermally tolerant clade D Symbiodinium was in greater abundance in corals from sites with high frequencies of TSAs. We recovered 2305 Symbiodinium ITS2 sequences from 242 coral colonies in lagoonal reef habitats at Pearl and Hermes Atoll, French Frigate Shoals, and Kaneohe Bay, Oahu in 2007. Sequences were grouped into 26 operational taxonomic units (OTUs) with 12 OTUs associated with Montipora and 21 with Porites. Both coral genera associated with Symbiodinium in clade C, and these co-occurred with clade D in M. capitata and clade G in P. lobata. The latter represents the first report of clade G Symbiodinium in P. lobata. In M. capitata (but not Porites spp.), there was a significant correlation between the presence of Symbiodinium in clade D and a thermal history characterized by high cumulative frequency of TSAs. The endogenous community composition of Symbiodinium and an association with clade D symbionts after long-term thermal disturbance appear strongly dependent on the taxa of the coral host.

Transmission mode predicts specificity and interaction patterns in coral-Symbiodinium networks

Most reef-building corals in the order Scleractinia depend on endosymbiotic algae in the genus Symbiodinium for energy and survival. Significant levels of taxonomic diversity in both partners result in numerous possible combinations of coral-Symbiodinium associations with unique functional characteristics. We created and analyzed the first coral-Symbiodinium networks utilizing a global dataset of interaction records from coral reefs in the tropical Indo-Pacific and Atlantic Oceans for 1991 to 2010. Our meta-analysis reveals that the majority of coral species and Symbiodinium types are specialists, but failed to detect any one-to-one obligate relationships. Symbiont specificity is correlated with a host’s transmission mode, with horizontally transmitting corals being more likely to interact with generalist symbionts. Globally, Symbiodinium types tend to interact with only vertically or horizontally transmitting corals, and only a few generalist types are found with both. Our results demonstrate a strong correlation between symbiont specificity, symbiont transmission mode, and community partitioning. The structure and dynamics of these network interactions underlie the fundamental biological partnership that determines the condition and resilience of coral reef ecosystems.

Hosts of the Plio-Pleistocene past reflect modern-day coral vulnerability

The risk of global extinction of reef-building coral species is increasing. We evaluated extinction risk using a biological trait-based resiliency index that was compared with Caribbean extinction during the Plio-Pleistocene, and with extinction risk determined by the International Union for Conservation of Nature (IUCN). Through the Plio-Pleistocene, the Caribbean supported more diverse coral assemblages than today and shared considerable overlap with contemporary Indo-Pacific reefs. A clear association was found between extant Plio-Pleistocene coral genera and our positive resilience scores. Regional extinction in the past and vulnerability in the present suggests that Pocillopora, Stylophora and foliose Pavona are among the most susceptible taxa to local and regional isolation. These same taxa were among the most abundant corals in the Caribbean Pliocene. Therefore, a widespread distribution did not equate with immunity to regional extinction. The strong relationship between past and present vulnerability suggests that regional extinction events are trait-based and not merely random episodes. We found several inconsistencies between our data and the IUCN scores, which suggest a need to critically re-examine what constitutes coral vulnerability.

Patterns of coral disease across the Hawaiian archipelago: relating disease to environment

In Hawaii, coral reefs occur across a gradient of biological (host abundance), climatic (sea surface temperature anomalies) and anthropogenic conditions from the human-impacted reefs of the main Hawaiian Islands (MHI) to the pristine reefs of the northwestern Hawaiian Islands (NWHI). Coral disease surveys were conducted at 142 sites from across the Archipelago and disease patterns examined. Twelve diseases were recorded from three coral genera (Porites, Montipora, Acropora) with Porites having the highest prevalence. Porites growth anomalies (PorGAs) were significantly more prevalent within and indicative of reefs in the MHI and Porites trematodiasis (PorTrm) was significantly more prevalent within and indicative of reefs in the NWHI. Porites tissue loss syndrome (PorTLS) was also important in driving regional differences but that relationship was less clear. These results highlight the importance of understanding disease ecology when interpreting patterns of disease occurrence. PorTrm is caused by a parasitic flatworm that utilizes multiple hosts during its life cycle (fish, mollusk and coral). All three hosts must be present for the disease to occur and higher host abundance leads to higher disease prevalence. Thus, a high prevalence of PorTrm on Hawaiian reefs would be an indicator of a healthy coral reef ecosystem. In contrast, the high occurrence of PorGAs within the MHI suggests that PorGAs are related, directly or indirectly, to some environmental co-factor associated with increased human population sizes. Focusing on the three indicator diseases (PorGAs, PorTrm, PorTLS) we used statistical modeling to examine the underlying associations between disease prevalence and 14 different predictor variables (biotic and abiotic). All three diseases showed positive associations with host abundance and negative associations with thermal stress. The association with human population density differed among disease states with PorGAs showing a positive and PorTrm showing a negative association, but no significant explanatory power was offered for PorTLS.

Growth anomalies on the coral genera Acropora and Porites are strongly associated with host density and human population size across the Indo-Pacific

Growth anomalies (GAs) are common, tumor-like diseases that can cause significant morbidity and decreased fecundity in the major Indo-Pacific reef-building coral genera, Acropora and Porites. GAs are unusually tractable for testing hypotheses about drivers of coral disease because of their pan-Pacific distributions, relatively high occurrence, and unambiguous ease of identification. We modeled multiple disease-environment associations that may underlie the prevalence of Acropora growth anomalies (AGA) (n = 304 surveys) and Porites growth anomalies (PGA) (n = 602 surveys) from across the Indo-Pacific. Nine predictor variables were modeled, including coral host abundance, human population size, and sea surface temperature and ultra-violet radiation anomalies. Prevalence of both AGAs and PGAs were strongly host density-dependent. PGAs additionally showed strong positive associations with human population size. Although this association has been widely posited, this is one of the first broad-scale studies unambiguously linking a coral disease with human population size. These results emphasize that individual coral diseases can show relatively distinct patterns of association with environmental predictors, even in similar diseases (growth anomalies) found on different host genera (Acropora vs. Porites). As human densities and environmental degradation increase globally, the prevalence of coral diseases like PGAs could increase accordingly, halted only perhaps by declines in host density below thresholds required for disease establishment.

ANTIGENIC RELATIONSHIPS BETWEEN IMMUNE GLOBULINS AND CERTAIN RELATED PARAPROTEINS IN MAN

The antigenic properties of normal 19S gamma-globulin, pathologic macroglobulins, beta(2A)-myeloma proteins, and Bence Jones proteins have been compared with 7S gamma-globulin and the small 3.5S units derived from it by gel diffusion precipitin techniques. These studies demonstrate that the determinant groups on the 7S gamma-globulin molecule responsible for the cross-reaction with each of the other proteins are associated with the two fragments of 7S gamma-globulin which have the antibody-combining sites. The antigenic specificity of the 7S gamma-globulin which distinguishes it from each of these proteins is associated primarily with the fragment that is richest in hexose and can not combine with antigen. However when compared with certain of the paraproteins additional antigenic specificity was also found to reside in the fragments with antibody-combining activity. The finding of similar antigenic relationships in rabbit gamma-globulins suggests that some of the biological properties associated only with the 7S gamma-globulins and not with the other immune globulins may reside in the fragment which also carries the antigenic specificity of the protein.

Preferential association of kappa IIIb light chains with monoclonal human IgM kappa autoantibodies

The predominance of the relatively uncommon V region subgroup isotype kappa III among the light chains of human monoclonal (IgM kappa) anti-IgG antibodies, (i.e., rheumatoid factors), was further documented through sequence analyses of ten such autoantibodies isolated from IgM-anti-IgG cold-insoluble immune complexes (mixed cryoglobulins). The amino-terminal sequence of all ten kappa-chains was characteristic for kappa III proteins and virtually identical to that of a prototype kappa III light chain. Similar sequence identity was found for kappa-chains isolated from three IgM kappa autoantibodies that formed cold-insoluble immune complexes with low-density lipoprotein (LDL). The thirteen light chains were found to be virtually identical in sequence for the first framework region (FR); ten of these proteins sequenced through the first complementarity-determining region (CDR) and into the second FR were markedly similar. The second CDR of five proteins was almost identical in sequence to that of the prototype kappa III-chain. Concordance was also demonstrated between the structural classification of the light chains as kappa III and their immunochemical classification as members of this V region subgroup. Serologic analyses of light chains isolated from seven IgM kappa autoantibodies (six anti-IgG, one anti-LDL) and of one intact IgM kappa anti-LDL antibody showed that each had antigenic determinants common to kappa II proteins. These light chains also expressed the antigenic determinant(s) of a V-region sub-subgroup of kappa III proteins designated kappa IIIb. Our studies confirm the preferential association of kappa III (and kappa IIIb) light chains with IgM kappa anti-IgG antibodies and demonstrate a similar association for IgM kappa anti-LDL antibodies. The finding that these and other types of IgM kappa autoantibodies, e.g., cold agglutinins, have remarkably similar light chains suggests an inherent restriction in the immune response to self-antigens.

Preferential association of kappa IIIb light chains with monoclonal human IgM kappa autoantibodies

The predominance of the relatively uncommon V region subgroup isotype kappa III among the light chains of human monoclonal (IgM kappa) anti-IgG antibodies, (i.e., rheumatoid factors), was further documented through sequence analyses of ten such autoantibodies isolated from IgM-anti-IgG cold-insoluble immune complexes (mixed cryoglobulins). The amino-terminal sequence of all ten kappa-chains was characteristic for kappa III proteins and virtually identical to that of a prototype kappa III light chain. Similar sequence identity was found for kappa-chains isolated from three IgM kappa autoantibodies that formed cold-insoluble immune complexes with low-density lipoprotein (LDL). The thirteen light chains were found to be virtually identical in sequence for the first framework region (FR); ten of these proteins sequenced through the first complementarity-determining region (CDR) and into the second FR were markedly similar. The second CDR of five proteins was almost identical in sequence to that of the prototype kappa III-chain. Concordance was also demonstrated between the structural classification of the light chains as kappa III and their immunochemical classification as members of this V region subgroup. Serologic analyses of light chains isolated from seven IgM kappa autoantibodies (six anti-IgG, one anti-LDL) and of one intact IgM kappa anti-LDL antibody showed that each had antigenic determinants common to kappa II proteins. These light chains also expressed the antigenic determinant(s) of a V-region sub-subgroup of kappa III proteins designated kappa IIIb. Our studies confirm the preferential association of kappa III (and kappa IIIb) light chains with IgM kappa anti-IgG antibodies and demonstrate a similar association for IgM kappa anti-LDL antibodies. The finding that these and other types of IgM kappa autoantibodies, e.g., cold agglutinins, have remarkably similar light chains suggests an inherent restriction in the immune response to self-antigens.

Identification of elastases associated with purified plasma membranes isolated from human monocytes and lymphocytes

Studies were carried out to understand the pathogenesis of amyloid formation and to localize the elastase-like enzymes postulated to be associated with the surface of human peripheral blood monocytes and lymphocytes. These enzymes are known to degrade serum amyloid A and amyloid A proteins. Pure plasma membrane preparations were obtained by allowing cells to attach to polyacrylamide beads, followed by their disruption. The purity of the membranes was monitored by electron microscopy and enzyme determinations. The extracted membrane enzymes which have molecular weights of 56000 and 30000, respectively, were inhibited by DFP, MeO-Suc-Ala-Ala-Pro-Val-CH2Cl, Ac-Pro-Phe-Arg-CH2Cl . HCl, and elastinal but were not inhibited by EDTA or epsilon-amino caproic acid, thus exhibiting the properties of elastases. These enzymes cleave serum amyloid A to amyloid protein A. In some individuals, cleavage stops at this point, while in others a second step occurs, resulting in complete protein degradation. This activity was comparable whether monocyte or lymphocyte plasma membranes were employed. Since lymphocyte dependent cytotoxicity has also been attributed to surface proteases, it is likely that a spectrum of membrane associated enzymes mediate important physiologic function of these mononuclear leukocytes.

Characterization of amyloid deposits and P component from a patient with factor X deficiency reveals proteins derived from a lambda VI light chain

Amyloid fibrils were isolated from a spleen obtained at surgery from a 58-year-old white man with primary amyloidosis presenting with factor X deficiency and responding dramatically to splenectomy. Gel filtration on Ultragel ACA 54 in 5 M guanidine 1 M acetic acid yielded components with molecular weights between 17,000 and 13,000. Two of them (17K and 15K) were studied in detail. Antigenic and amino acid sequence analysis showed that these proteins were related to lambda VI immunoglobulin light chain. The predominant protein subunits of the amyloid fibril of the deposits (17K) was processed at the carboxy terminus in the same section of the constant region as the only other lambda VI amyloid protein previously reported. Amino terminal sequence of the 15K protein revealed not only degradation at the C terminal, but also minor degradation at the amino terminal (three residues difference from the 17K species). P component was also isolated from the spleen and characterized. This represents the first antigenic and sequence analysis of tissue amyloid proteins and P component from a patient presenting with factor X deficiency and another example of amyloid proteins derived from the newly discovered amyloidogenic lambda VI light chain subgroup.

Primary structure of an amyloid prealbumin variant in familial polyneuropathy of Jewish origin

The complete amino acid sequence of three related amyloid proteins (Mr 14,000, 10,000, and 5,000) derived from tissues of a Jewish patient who suffered from a variant of familial polyneuropathic amyloidosis was determined. The protein, which contains 127 residues, is identical to a human serum prealbumin subunit. Only one amino acid substitution, glycine for threonine, was detected at position 49, where enzymatic cleavage occurred, yielding Mr 5,000 and 10,000 fragments which represent the amino terminus (residues 1-48) and carboxyl terminus (residues 49-127) of the molecule, respectively. Thus, a prealbumin variant and its fragments constitute the amyloid fibrils in a heredofamilial amyloidosis syndrome of dominant inheritance.

Familial renal amyloidosis: case reports and genetic studies

Rapidly progressive biopsy-proved renal amyloidosis developed in three brothers, aged 49, 52, and 55, or Irish-American origin. None had evidence of a plasma cell dyscrasia, a monoclonal serum or urine protein, or any underlying chronic disease. Immunoperoxidase staining of one pulmonary and one renal biopsy specimen was negative for Amyloid A (AA), Amyloid L (AL), and prealbumin. To investigate factors that might play a role in the disease, the subjects and 21 relatives were typed for antigens of the A, B, C, and DR loci and the linked marker genes for factor B and glyoxalase. The ability of macrophages to degrade serum amyloid A (SAA) [1] was examined. One brother yielded an intermediate AA-like produce similar to what is seen in most patients with AA or AL amyloidosis and 40 percent of normal subjects. The other two degraded SAA completely to small peptides. Analysis of the families revealed first that the disease was not linked to the major histocompatibility complex. We were unable to demonstrate a genetic relationship between processing of SAA by peripheral mononuclear cells and the human leukocyte antigen locus. Finally, the pattern of SAA degradation was not associated with the development of the disease.

Amyloidosis associated with renal cell carcinoma of the AA type

Amyloid fibrils were found at postmortem examination in a 70 year old woman with generalized amyloidosis associated with renal carcinoma (hypernephroma). Clinically, her amyloid disease presented as nephrotic syndrome. It was demonstrated by electrophoretic and amino acid sequence analysis studies that the amyloid fibrils contained AA protein identical to that found in amyloidosis associated with chronic inflammatory and infectious diseases as well as in the genetic form of familial Mediterranean fever.

Idiopathic AL-kiv amyloidosis presenting as giant hepatomegaly

The 11/2-yr course of idiopathic systemic amyloidosis in a 63-yr-old woman was characterized by inanition, subcutaneous ecchymoses and giant hepatomegaly, the liver weighing 8.5 kg at autopsy. Skeletal survey and bone marrow aspirate were normal. The major components of isolated amyloid fibrils were 16,000- and 23,000-dalton proteins. The 16,000-dalton component was shown by amino acid sequencing to be a fragment of the kappa (k)iv light chain, the first such case. These clinicochemical correlations suggest that isolated massive hepatomegaly may prove to be a hallmark of idiopathic amyloid light chain-related protein k amyloidosis.

Bence Jones proteins and light chains of immunoglobulins. Preferential association of the V lambda VI subgroup of human light chains with amyloidosis AL (lambda)

An antiserum prepared against a lambda-Bence Jones protein from a patient (SUT) who had multiple myeloma and amyloidosis had specificity for lambda-light chains of the chemically defined variable (V) region lambda-chain subgroup lambda VI. Sequence analyses of protein SUT and of five other lambda-light chains recognized immunologically as of the V lambda VI subgroup revealed that all six proteins had the N-terminal sequence characteristic for prototype lambda VI proteins. The isotypic nature of the V lambda VI subgroup was demonstrated immunochemically: lambda VI molecules were detected among light chains isolated from the IgG proteins of each of 12 normal individuals and lambda VI antigenic determinants were also detectable on the intact IgG proteins. The frequency of lambda VI molecules among lambda-type light chains is estimated to be approximately 5% based on the finding that 5 of 91 lambda Bence Jones proteins were of the V lambda VI subgroup. Proteins of the V lambda VI subgroup, in contrast to those of the other five chemically-classified lambda chain subgroup, appear to be preferentially associated with the amyloid process as evidenced by the fact that all six lambda VI proteins were obtained from patients with amyloidosis AL and, in addition, 5 of 42 lambda-type monoclonal immunoglobulins from patients with primary or myeloma-associated amyloidosis were classified by immunodiffusion analyses as having lambda VI-type light chains.

The modification of human immunoglobulin binding to staphylococcal protein A using diethylpyrocarbonate

Human IgG subclasses 1, 2, and 4, as well as proteins of the IgG3 subclass that are allotype G3m (s+t+), bind avidly to staphylococcal protein A by means of their Fc portion. Proteins of the IgG3 subclass that are allotype G3m (s-t-) do not bind. The importance of a histidine residue at position 435 has been implicated from comparison of amino acid sequences of immunoglobulins that bind with those that do not bind to staphylococcal protein A, as well as from crystallographic data. Modification of histidines at a low concentration of diethylpyrocarbonate successfully and reversibly alters the binding of immunoglobulins to staphylococcal protein A with only minimal change in the antigenic properties. This method provides strong evidence for the critical importance of histidine in the binding of immunoglobulins to staphylococcal protein A.

The modification of human immunoglobulin binding to staphylococcal protein A using diethylpyrocarbonate

Human IgG subclasses 1, 2, and 4, as well as proteins of the IgG3 subclass that are allotype G3m (s+t+), bind avidly to staphylococcal protein A by means of their Fc portion. Proteins of the IgG3 subclass that are allotype G3m (s-t-) do not bind. The importance of a histidine residue at position 435 has been implicated from comparison of amino acid sequences of immunoglobulins that bind with those that do not bind to staphylococcal protein A, as well as from crystallographic data. Modification of histidines at a low concentration of diethylpyrocarbonate successfully and reversibly alters the binding of immunoglobulins to staphylococcal protein A with only minimal change in the antigenic properties. This method provides strong evidence for the critical importance of histidine in the binding of immunoglobulins to staphylococcal protein A.

Structural studies on an IgM-lambda pyroglobulin

An IgM-lambda pyroglobulin from a patient with Waldenström's syndrome was studied. Heavy and light chains were separated and their N-terminal amino acid sequence determined. The heavy chain was unblocked and belonged to the VHIII subclass, and the light chain belonged to the lambda I subclass. Factors influencing pyroprecipitability were examined through experiments designed to study some of the physical and chemical properties of an IgM-lambda pyroglobulin. Pyroprecipitability was affected by pH, ionic strength, urea, and reducing agents, suggesting an involvement of noncovalent electrostatic interactions. It was also demonstrated through recombinant experiments that it is necessary to have covalently joined homologous heavy and light chains in pentameric form for pyroprecipitation to occur. Since neither heavy nor light chains had any unique structural features, the reasons for this property remain obscure but may reflect the result of conformational factors.

gamma Heavy chain disease in man: cDNA sequence supports partial gene deletion model

Human gamma heavy chain disease (HCD) is characterized by the presence in serum of a short monoclonal Ig gamma chain unattached to light chains. Although most HCD proteins have internal deletions, in some the defect is NH2-terminal. The OMM gamma 3 HCD serum protein is of the latter type, having undergone an extensive NH2-terminal deletion with a sequence starting within the hinge. A cell line synthesizing the OMM protein has enabled us to study the biogenesis of the abnormal molecule. In vitro translation of isolated mRNA yields a protein containing a hydrophobic NH2-terminal leader sequence. In the intact cell, the precursor molecule is processed normally to yield a protein with an NH2-terminal sequence homologous to the beginning of the variable (V) region. The nucleotide sequence of cDNA prepared from the OMM mRNA encodes a 19-amino acid leader followed by the first 15 residues of the V region. An extensive internal deletion encompasses the remainder of the V and the entire CH1 domain. Immediately following the short V region, there is information in the cDNA for the entire normal hinge. The primary synthetic product is thus an internally deleted molecule that undergoes postsynthetic degradation to yield the NH2-terminally deleted serum protein. The structure of the OMM mRNA suggests that the protein abnormality results from a partial gene deletion rather than defective splicing.

Staphylococcal protein A and human IgG subclasses and allotypes

Staphylococcal protein A binds molecules belonging to the IgG1, IgG2, and IgG4 subclasses. IgG3 proteins generally do not bind, except for those coded by the two gamma 3 alleles, which are G3m(u-): G3m(b0,b3,b5,s,v). G3m(u) is located in the CH2 domain. The difference between G3m(u-) and G3m(u+) IgG3 proteins correlates with the sequence at position 339 in the CH2 domain--Ala and Thr respectively. There is another structural difference in the CH3 domain which correlates with protein A binding and non-binding: all IgG proteins that bind protein A have His at position 435, whereas those that do not, have Arg at that position.

Factors affecting the release of proteases from peripheral blood monocytes

Serum amyloid A (SAA) protein is degraded by serine proteases associated with the external plasma membrane of peripheral blood monocytes. The plasma membrane-associated enzymes are serine proteases of high molecular weight. In addition, cells grown in suspension release enzymatic activity into the surrounding medium. The origin and nature of the released SAA degrading enzymes remains obscure, but they appear to belong to the general class of serine proteases. Conditions of culture were determined which minimized release of the secreted enzymes and will ultimately permit the characterization of the properties of the membrane associated enzymes uncontaminated with the cytoplasmic proteases. It seems likely that there are two compartments of proteases-one surface-associated and one cytoplasmic.

A variant of prealbumin from amyloid fibrils in familial polyneuropathy of Jewish origin

Amyloid fibrils were isolated from spleen and thyroid obtained at autopsy from one patient (S.K.O.) of Jewish origin with familial amyloidotic polyneuropathy. Gel filtration on Sephadex G100 after solubilization in 5 M guanidine HCl yielded three major components with 14,000, 9,000, and 5,000 mol wt, respectively. The two larger components shared antigenic determinants with human prealbumin. Amino acid analysis and amino terminal sequence studies revealed the 14,000-mol wt protein to be an intact prealbumin subunit. The 9,000-mol wt fragment obtained in highest yield encompassed the region from position 49-127 and the 5,000 mol wt fraction encompassed the amino terminal of prealbumin (position 1-48). An amino acid substitution (Gly/Thr) was detected at position 49, where enzymatic cleavage occurred. Thus, several prealbumin-derived fragments, predominantly the carboxyl end, constitute the amyloid fibrils in a heredofamilial amyloidosis syndrome of dominant inheritance.

The effect of combination therapy (steroids, immunosuppressives, and plasmapheresis) on 5 mixed cryoglobulinemia patients with renal, neurologic, and vascular involvement

A prospective clinical study evaluated the effects of combined chemotherapy, steroids and plasmapheresis on 5 patients with mixed cryoglobulinemia with renal or neurologic and vasculitic manifestations. Treatment included prednisone (1mg/kg/day), chlorambucil (white blood cell count at greater than 3,000/mm3), and plasmapheresis (1 to 3 liters/week). There was healing of cutaneous ulcers (3/3), improvement in renal function (4/4), and diminution of purpura (2/2), but little improvement in peripheral neuropathy. Complications included leukopenia, perineal ulcers, and osteomyelitis.

Demonstration of membrane-bound proteolytic activity on the surface of mononuclear leukocytes

The existence of proteolytic enzymes bound to the surface of migrating cells has often been surmised. That such enzymes are present on mononuclear leukocytes was suggested by studies showing that serum amyloid A (SAA), the presumed precursor of amyloid protein A, is degraded in the presence of monocytes without endocytosis and with only negligible activity in the cells' supernates. Experiments using immunofluorescence were designed to support this view. It was shown that SAA binds to the cells' surface at low temperatures, whereas binding at 37 degrees C could only be demonstrated when the cells were pretreated with the serine protease inhibitor, diisopropyl-fluorophosphate (DFP) or the elastase inhibitor Ac-Ala-Ala-Pro-Val-CH2Cl. Exposure of the cells to these inhibitors before incubation with SAA at 0 degrees C permitted detection of the protein for an indefinite period of time. At 37 degrees C the DFP-treated cells polarized and eventually lost the surface-bound protein. No interiorized SAA could be demonstrated. Radioautography of cells that had been treated with 3H-DFP revealed grains on the plasma membrane and in the cytoplasm of sectioned monocytes, whereas only 8-15% of lymphocytes were labeled. In lymphocytes radioactivity was restricted to the surface membrane. Additional experiments showed that alpha-naphthyl acetate esterase activity is also located on the surface of monocytes and a subpopulation of lymphocytes. These observations have led to the conclusion that some functions of mononuclear leukocytes may be mediated by enzymes associated with the external surface of these cells.

Antiidiotypic activity in the IgM fractions of mixed cryoglobulins

To search for human antiidiotypic antibodies, cryoglobulins from 11 patients with mixed cryoglobulinemia, 7 of whom had evidence of prior hepatitis B virus infection were separated on Sephadex G-200. Each of the IgM, 8 of which were IgM kappa, was tested with the F(ab')2 fragments prepared from each of the IgG fractions in a solid phase assay by using binding of 125I Staph A protein after the addition of rabbit anti-IgM. Unlike rabbit anti-Fab, which reacted approximately to the same extent with all F(ab')2 fragments, the IgM varied in their binding to F(ab')2 fragments, reacting with 2 to 10 antigens. Nine reacted with their autologous antigen and in 5 instances autologous reactivity exceeded that with heterologous F(ab')2 fragments. Reactivity was not related to prior exposure to HBV. Though absorption with Cohn fraction II F(ab')2 fragments generally abolished reactivity, 1 IgM protein continued to react with nine F(ab')2 fragments and 4 others with the F(ab')2 fragment from a single patient. Even when they contained only a single type of kappa-chain, the IgM appeared to contain multiple antibodies since absorption with solid phase Fc fragments or IgG removed anti-Fc rheumatoid factor activity but failed to affect binding to F(ab')2 fragments. Five of 7 IgM were able to bind the Fv region of a monoclonal IgM kappa-protein. Some of the anti-Fab antibodies were directed against idiotypes since addition of HbsAg to F(ab')2 fragments from HBsAb-positive IgG resulted in a marked decrease in binding of the IgM fraction in 6 out of 7 studies, whereas no decrease was noted in 6 experiments with F(ab')2 fragments that were HBsAb negative. The possible existence of antibodies against other idiotypes or other determinants in the Fab region cannot be excluded.

Antiidiotypic activity in the IgM fractions of mixed cryoglobulins

To search for human antiidiotypic antibodies, cryoglobulins from 11 patients with mixed cryoglobulinemia, 7 of whom had evidence of prior hepatitis B virus infection were separated on Sephadex G-200. Each of the IgM, 8 of which were IgM kappa, was tested with the F(ab')2 fragments prepared from each of the IgG fractions in a solid phase assay by using binding of 125I Staph A protein after the addition of rabbit anti-IgM. Unlike rabbit anti-Fab, which reacted approximately to the same extent with all F(ab')2 fragments, the IgM varied in their binding to F(ab')2 fragments, reacting with 2 to 10 antigens. Nine reacted with their autologous antigen and in 5 instances autologous reactivity exceeded that with heterologous F(ab')2 fragments. Reactivity was not related to prior exposure to HBV. Though absorption with Cohn fraction II F(ab')2 fragments generally abolished reactivity, 1 IgM protein continued to react with nine F(ab')2 fragments and 4 others with the F(ab')2 fragment from a single patient. Even when they contained only a single type of kappa-chain, the IgM appeared to contain multiple antibodies since absorption with solid phase Fc fragments or IgG removed anti-Fc rheumatoid factor activity but failed to affect binding to F(ab')2 fragments. Five of 7 IgM were able to bind the Fv region of a monoclonal IgM kappa-protein. Some of the anti-Fab antibodies were directed against idiotypes since addition of HbsAg to F(ab')2 fragments from HBsAb-positive IgG resulted in a marked decrease in binding of the IgM fraction in 6 out of 7 studies, whereas no decrease was noted in 6 experiments with F(ab')2 fragments that were HBsAb negative. The possible existence of antibodies against other idiotypes or other determinants in the Fab region cannot be excluded.

The role of cryoglobulins and immune complexes in vasculitis

Immune complexes play a major role in a variety of diseases such as lupus and rheumatoid arthritis. Cryoglobulins, especially those of the mixed type, represent a type of immune complex that is particularly easy to isolate, and hence lend themselves readily to the identification of the responsible precipitating agents. This report presents the clinical, laboratory, and pathologic features of 40 patients with mixed cryoglobulinemia and offers some speculation based on currently available evidence on the role of cryoglobulins in pathogenesis.

Human monoclonal macroglobulins with specificity for Klebsiella K polysaccharides that contain 3,4-pyruvylated-D-galactose and 4,6-pyruvylated-D-galactose

Two human IgM myeloma proteins, IgMWEA and IgMMAY, were found to react with agar and Klebsiella polysaccharides that contain pyruvylated D-galactose (DGal). Quantitative precipitin data and precipitin inhibition studies with methyl alpha- and beta-glycosides of 4,6-pyruvylated-D-galactose showed their combining sites to be different, although each was directed against the pyruvylated-D-Gal, one reacting most specifically with Klebsiella polysaccharides with terminal nonreducing beta-linked 2,4 pyruvylated-D-Gal, whereas the other reacted equally well with Klebsiella polysaccharides that contain 3,4 beta-linked and 4,6 alpha-linked terminal nonreducing pyruvylated-DGal. Inhibition studies showed that both sites are directed toward one of the two space isomers of 3,4- or 4,6-pyruvylated DGal, the form in which the methyl group of the pyruvate is equatorial, or endo, and its carboxyl group axial, or exo, to the plane of the acetal ring. Coprecipitation studies showed the combining site of IgMWEA to be located on an (Fab')2 fragment and not on the (Fc)5mu fragment. The monoclonal peak in the serum of IgMMAY was specifically precipitated by Klebsiella polysaccharide. Myeloma proteins with specificities of this type may occur with reasonable frequency in humans and may be a consequence of clonal expansion from inapparent infection, carrier states, or disease produced by various Klebsiella organisms.