Foodborne and airborne polyethersulfone nanoplastics respectively induce liver and lung injury in mice: Comparison with microplastics.

Micro/nanoplastics (MNP) are ubiquitous in the environment and multiple living organisms. The toxicity of some common types of MNP, e.g., polyethersulfone (PES) MNP, remains poorly understood. Multi-omics approaches were used in this study to determine the effects of foodborne and airborne PES MNP on liver and lung, respectively. Foodborne MNP were capable of inducing gut microbial dysbiosis, gut and serum metabolic disruption, and liver transcriptomic dysregulation, and affecting serum antioxidant activity and liver function, resulting in liver injury. As for the airborne MNP, they were found to induce nasal and lung microbial dysbiosis, serum and lung metabolic disruption, and liver transcriptome disturbance, and cause disrupted serum antioxidant activity and lung injury. Foodborne and airborne PES NP were found to respectively induce greater liver and lung toxicity than MP, which could be associated with the differences between NP and MP exposures. The relevant results suggest that foodborne PES MNP could disrupt the "gut microbiota-gut-liver" axis and induce hepatic injury, while airborne PES MNP could affect the "airborne microbiota-lung" axis and cause lung injury. The findings could benefit the diagnoses of liver and lung injury respectively induced by foodborne and airborne PES MNP, as well as the proper use of PES in human living environment.

Effects of partial reduction of polystyrene micro-nanoplastics on the immunity, gut microbiota and metabolome of mice.

Microplastic (MP) and nanoplastic (NP) could cause gut microbiota alterations. Although micro/nanoplastic (MNP) degradation is attracting increasing scientific interest, the evaluation of MNP reduction in gut needs to be further investigated. This study aimed to determine whether partial reduction of polystyrene MNP in gut could affect the immunity, gut microbiota and metabolome of mice. Serum eotaxin/CCL11 was at a lower level in the mice exposed to 200 µg and 500 µg NP (i.e., 2NP and 5NP groups, respectively) compared to those exposed to 500 µg MP (i.e., 5 MP group), while serum IL-2 and IL-4 were both greater in the 5NP group compared to the 5 MP group. The gut bacterial alpha diversity, fungal diversity and evenness were all similar among the MNP and control groups. However, the gut fungal richness was greater in both the 5NP and 5 MP groups compared to the control group. The gut bacterial and fungal compositions were both different between the MNP and control groups. Multiple gut bacteria and fungi showed different levels between the 2NP and 5NP groups, as well as between the 2NP and 5 MP groups. Increased Staphylococcus and decreased Glomus were determined in the 2NP group compared to both the 5NP and 5 MP groups. A Lactobacillus phylotype was found as the sole gatekeeper in the bacterial network of the 2NP group, while a Bifidobacterium phylotype contributed most to the stability of the bacterial networks of both the 5NP and 5 MP groups. Multiple differential gut metabolic pathways were found between the 2NP and 5NP/5 MP groups, and mTOR signaling pathway was largely upregulated in the 2NP group compared to both the 5NP and 5 MP groups. The relevant results could help with the evaluation of partial reduction of MNP in gut.

Alterations of gut and oral microbiota in the individuals consuming take-away food in disposable plastic containers.

Microplastics (MP) and nanoplastics (NP) exist in the disposable plastic take-away containers. This study aims to determine the gut and oral microbiota alterations in the individuals frequently and occasionally consuming take-away food in disposable plastic containers (TFDPC), and explore the effect of micro/nanoplastics (MNP) reduction on gut microbiota in mice. TFDPC consumption are associated with greater presences of gastrointestinal dysfunction and cough. Both occasional and frequent consumers have altered gut and oral microbiota, and their gut diversity and evenness are greater than those of non-TFDPC consuming cohort. Multiple gut and oral bacteria are associated with TFDPC consumers, among which intestinal Collinsella and oral Thiobacillus are most associated with the frequent consumers, while intestinal Faecalibacterium is most associated with the occasional consumers. Although some gut bacteria associated with the mice treated with 500 µg NP and 500 µg MP are decreased in the mice treated with 200 µg NP, the gut microbiota of the three MNP groups are all different from the control group. This study demonstrates that TFDPC induces gut and oral microbiota alterations in the consumers, and partial reduction of the size and amount of MNP cannot rectify the MNP-induced gut microbial dysbiosis.

Airborne polystyrene microplastics and nanoplastics induce nasal and lung microbial dysbiosis in mice.

Microplastics (MP) and nanoplastics (NP) have been found in multiple environments and creatures. However, their effects on the airway microbiota still remain poorly understood. In this study, a series of bioinformatic and statistical analyses were carried out to explore the influence of airborne MP and NP on the nasal and lung microbiota in mice. Both MP and NP were capable of inducing nasal microbial dysbiosis, and MP had a stronger influence on the lung microbiota than NP. Multiple nasal and lung bacteria were associated with MP and NP groups, among which nasal Staphylococcus and lung Roseburia were most associated with MP group, while nasal Prevotella and lung unclassified_Muribaculaceae were most associated with NP group. The nasal Staphylococcus, lung Roseburia, lung Eggerthella and lung Corynebacterium were associated with both MP and NP groups, which were potential biomarkers of micro/nanoplastics-induced airway dysbiosis. SAR11_Clade_Ia and SAR11_Clade_II were associated with both nasal and lung microbiota in MP group, while no such bacterium was determined in NP group. The relevant results suggest that both airborne MP and NP could induce nasal and lung microbial dysbiosis, and the relevant preventative and curable strategies deserve further investigations.

Characteristics of the intestinal bacterial microbiota profiles in Bifidobacterium pseudocatenulatum LI09 pre-treated rats with D-galactosamine-induced liver injury.

Bifidobacterium pseudocatenulatum LI09 could prevent D-galactosamine-induced liver injury. Our previous study has preliminarily determined that different intestinal microbiota profiles existed in the LI09-treated rats. Due to the sample size limitation, some subsequent analyses could not be achieved. In the current study, we conducted different experiments and bioinformatic analyses to characterise the distinct intestinal bacterial microbiota profiles in the LI09-treated rats with liver injury (i.e., LI09 group). Partition around medoids clustering analysis determined two intestinal microbiota profiles (i.e., Cluster_1_LI09 and Cluster_2_LI09) in LI09 group. Compared with Cluster_2_LI09, Cluster_1_LI09 group was determined at less dysbiotic microbial status and with lower level of liver injury. The two microbiota profiles were determined with distinct representative amplicon sequence variants (ASVs), among which, ASV1_Akkermansia and ASV3_Bacteroides were most associated with Cluster_1_LI09 and Cluster_2_LI09, respectively. Multiple representative phylotypes in Cluster_1_LI09 negatively correlating with liver function variables were assigned to Parabacteroides, suggesting Parabacteroides could benefit LI09 on modulating the liver function. In addition, ASV310_Lachnospiraceae, ASV501_Muribaculaceae and ASV484_Lachnospiraceae were determined as network gatekeepers in Cluster_1_LI09 network. The relevant results suggest that some intestinal bacteria could assist LI09 in lowering the intestinal microbial dysbiosis in the rats with liver injury, and their clinical application deserves further investigation.

Characterising the Intestinal Bacterial and Fungal Microbiome Associated With Different Cytokine Profiles in Two Bifidobacterium strains Pre-Treated Rats With D-Galactosamine-Induced Liver Injury.

Multiple probiotics have protective effects against different types of liver injury. Different intestinal microbes could be beneficial to the protective effects of the probiotics on the treated cohorts in different aspects. The current study was designed to determine the intestinal bacterial and fungal microbiome associated with different cytokine profiles in the Bifidobacterium pseudocatenulatum LI09 and Bifidobacterium catenulatum LI10 pretreated rats with D-galactosamine-induced liver injury. In this study, partition around medoids clustering analysis determined two distinct cytokine profiles (i.e., CP1 and CP2) comprising the same 11 cytokines but with different levels among the LI09, LI10, positive control (PC), and negative control (NC) cohorts. All rats in PC and NC cohorts were determined with CP1 and CP2, respectively, while the rats with CP1 in LI09 and LI10 cohorts had more severe liver injury than those with CP2, suggesting that CP2 represented better immune status and was the "better cytokine profile" in this study. PERMANOVA analyses showed that the compositions of both bacterial and fungal microbiome were different in the LI10 cohorts with different cytokine profiles, while the same compositions were similar between LI09 cohorts with different cytokine profiles. The phylotype abundances of both bacteria and fungi were different in the rats with different cytokine profiles in LI09 or LI10 cohorts according to similarity percentage (SIMPER) analyses results. At the composition level, multiple microbes were associated with different cytokine profiles in LI09 or LI10 cohorts, among which Flavonifractor and Penicillium were the bacterium and fungus most associated with LI09 cohort with CP2, while Parabacteroides and Aspergillus were the bacterium and fungus most associated with LI10 cohort with CP2. These microbes were determined to influence the cytokine profiles of the corresponding cohorts. At the structure level, Corynebacterium and Cephalotrichiella were determined as the two most powerful gatekeepers in the microbiome networks of LI09 cohort CP2, while Pseudoflavonifractor was the most powerful gatekeeper in LI10 cohort with CP2. These identified intestinal microbes were likely to be beneficial to the effect of probiotic Bifidobacterium on the immunity improvement of the treated cohorts, and they could be potential microbial biomarkers assisting with the evaluation of immune status of probiotics-treated cohorts.

Characteristics of the gut microbiota in Bifidobacterium catenulatum LI10 pretreated rats with lower levels of D-galactosamine-induced liver damage.

AIMS: Liver damage has caused great illness in human beings. Bifidobacterium catenulatum LI10 has been determined with protective effect against D-galactosamine-induced liver damage. However, due to the sample limitation, the individual difference in its protective effect was not determined. The current study was designed to characterize the gut microbiota of LI10-pretreated rats with lower levels of liver damage. METHODS AND RESULTS: A series of experiments and bioinformatic analyses were carried out. Two rat cohorts with different levels of liver damage were determined, that is, Non-Severe and Severe cohorts. Six out of the seven measured liver function variables were lower in the Non-Severe cohort, while four cytokine variables also yielded differences between the two cohorts. The Non-Severe and Severe cohorts were determined with distinct gut microbiota, among which ASV14_Parabacteroides and ASV7_Bacteroides were most associated with Non-Severe and Severe cohorts, respectively. Five phylotypes were determined as structural gatekeepers in the microbiota network of Non-Severe cohort, ASV135_Lachnospiraceae_NK4A136 of which contributed most to the stability of the network. CONCLUSIONS: The relevant findings suggest that some gut bacteria could benefit the protective effect of LI10 on lowering the severity of rat liver damage. SIGNIFICANCE AND IMPACT OF THE STUDY: The bacteria benefiting the protective effects of potential probiotics could be further investigated for future clinical application.

Multiple Intestinal Bacteria Associated with the Better Protective Effect of Bifidobacterium pseudocatenulatum LI09 against Rat Liver Injury.

Bifidobacterium pseudocatenulatum LI09 could protect rats from D-galactosamine- (D-GalN-) induced liver injury. However, individual difference in the protective effects of LI09 on the liver injury remains poorly understood. The present study is aimed at determining the multiple intestinal bacteria associated with the better protective effect of LI09 against D-GalN-induced rat liver injury. Two rat cohorts, i.e., the nonsevere and severe cohorts, were divided based on their liver injury severity. Higher level of ALB and lower levels of ALT, AST, TBA, TB, IL-5, and MIP-3α were determined in the nonsevere cohort than the severe cohort. The alpha diversity indices (i.e., observed species, Shannon, and Pielou indices) did not yield significant differences between the intestinal microbiota of the nonsevere and severe cohorts. The intestinal microbiota composition was different between the two cohorts. Ten phylotypes assigned to Bacteroides, Clostridia_UCG-014, Clostridium Lachnospiraceae, Lachnospiraceae_NK4A136, and Parabacteroides were closely associated with the nonsevere cohort, among which, ASV8_Lachnospiraceae_NK4A136 was the most associated one. At the structure level, two groups of phylotypes with most correlations were determined in the intestinal microbiota networks of the two cohorts. Among them, ASV135_Lachnospiraceae_NK4A136 was the most powerful gatekeeper in the microbiota network of the nonsevere cohort. In conclusion, some intestinal bacteria, e.g., Lachnospiraceae_NK4A136, Parabacteroides, and Clostridium, were associated with the better protective effect of LI09 against D-GalN-induced rat liver injury. They were likely to enhance the effectiveness of LI09, and their clinical application deserves further investigation.

Multiple bacteria associated with the more dysbiotic genitourinary microbiomes in patients with type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) influences the human health and can cause significant illnesses. The genitourinary microbiome profiles in the T2DM patients remain poorly understood. In the current study, a series of bioinformatic and statistical analyses were carried out to determine the multiple bacteria associated with the more dysbiotic genitourinary microbiomes (i.e., those with lower dysbiosis ratio) in T2DM patients, which were sequenced by Illumina-based 16S rRNA gene amplicon sequencing. All the genitourinary microbiomes from 70 patients with T2DM were clustered into three clusters of microbiome profiles, i.e., Cluster_1_T2DM, Cluster_2_T2DM and Cluster_3_T2DM, with Cluster_3_T2DM at the most dysbiotic genitourinary microbial status. The three clustered T2DM microbiomes were determined with different levels of alpha diversity indices, and driven by distinct urinalysis variables. OTU12_Clostridiales and OTU28_Oscillospira were likely to drive the T2DM microbiomes to more dysbiotic status, while OTU34_Finegoldia could play a vital role in maintaining the least dysbiotic T2DM microbiome (i.e., Cluster_1_T2DM). The functional metabolites K08300_ribonuclease E, K01223_6-phospho-beta-glucosidase and K00029_malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) were most associated with Cluster_1_T2DM, Cluster_2_T2DM and Cluster_3_T2DM, respectively. The characteristics and multiple bacteria associated with the more dysbiotic genitourinary microbiomes in T2DM patients may help with the better diagnosis and management of genitourinary dysbiosis in T2DM patients.

Altered T-Cell Receptor ß-Chain and Lactate Dehydrogenase Are Associated With the Immune Pathogenesis of Biliary Atresia.

Background: Biliary atresia (BA) is considered to be an autoimmune-mediating inflammatory injury. The pathogenesis of BA has been proposed with the clonal transformation of T cells expressing analogous T-cell receptor ß-chain variable regions (TRBVs). Methods: The TRBV profile of the peripheral blood mononuclear cells (PBMCs) in infants with BA and control infants (healthy donors, HDs), respectively, were characterized by using high-throughput sequencing (HTS). The diversity of T cells was analyzed based on the frequency of complementarity-determining region 3 (CDR3) or V(CDR3)J. Moreover, the correlation between absolute lymphocyte count (ALC) and lactate dehydrogenase (LDH) or diversity (clonality) indices, respectively, were analyzed for subjects with BA and HD. Results: The diversity indices of CDR3, V(CDR3)J in BA are lower than those in subjects with HD, in addition, there are significantly different levels of neutrophile, neutrophile/lymphocyte ratio (NLR), and LDH between groups of BA and HD. The correlation between ALC and diversity index is significant in subjects with HD but is not for subjects with BA. Conversely, the relationship between ALC and LDH is significant in subjects with BA but is not for subjects with HD. Moreover, 12 CDR3 motifs are deficient or lower expression in BA compared with that in the HD group. Conclusion: Our results demonstrate that the profile of TRBV repertoire is significantly different between subjects with BA and HD, and suggest that the immune imbalance and elevated LDH level are associated with the pathogenesis of BA. Moreover, the values of neutrophile, NLR, and LDH could be used for the differential diagnosis of BA.

Recovery Dynamics of Intestinal Bacterial Communities of CCl4-Treated Mice with or without Mesenchymal Stem Cell Transplantation over Different Time Points.

Liver injury has caused significant illness in humans worldwide. The dynamics of intestinal bacterial communities associated with natural recovery and therapy for CCl4-treated liver injury remain poorly understood. This study was designed to determine the recovery dynamics of intestinal bacterial communities in CCl4-treated mice with or without mesenchymal stem cell transplantation (i.e., MSC and CCl4 groups) at 48 h, 1 week (w), and 2 w. MSCs significantly improved the histopathology, survival rate, and intestinal structural integrity in the treated mice. The gut bacterial communities were determined with significant changes in both the MSC and CCl4 groups over time, with the greatest difference between the MSC and CCl4 groups at 48 h. The liver injury dysbiosis ratio experienced a decrease in the MSC groups and a rise in the CCl4 groups over time, suggesting the mice in the MSC group at 48 h and the CCl4 group at two weeks were at the least gut microbial dysbiosis status among the corresponding cohorts. Multiple OTUs and functional categories were associated with each of the bacterial communities in the MSC and CCl4 groups over time. Among these gut phylotypes, OTU1352_S24-7 was determined as the vital member in MSC-treated mice at 48 h, while OTU453_S24-7, OTU1213_Ruminococcaceae, and OTU841_Ruminococcus were determined as the vital phylotypes in CCl4-treated mice at two weeks. The relevant findings could assist the diagnosis of the microbial dysbiosis status of intestinal bacterial communities in the CCl4-treated cohorts with or without MSC transplantation.

Vital Members in the More Dysbiotic Oropharyngeal Microbiotas in H7N9-Infected Patients.

The dysbiosis of oropharyngeal (OP) microbiota is associated with multiple diseases, including H7N9 infection. Different OP microbial colonization states may reflect different severities or stages of disease and affect the effectiveness of the treatments. Current study aims to determine the vital bacteria that could possibly drive the OP microbiota in the H7N9 patients to more severe microbial dysbiosis state. The OP microbiotas of 42 H7N9 patients and 30 healthy subjects were analyzed by a series of bioinformatics and statistical analyses. Two clusters of OP microbiotas in H7N9 patients, i.e., Cluster_1_Diseased and Cluster_2_Diseased, were determined at two microbial colonization states by Partition Around Medoids (PAM) clustering analysis, each characterized by distinct operational taxonomic units (OTUs) and functional metabolites. Cluster_1_Diseased was determined at more severe dysbiosis status compared with Cluster_2_Diseased, while OTU143_Capnocytophaga and OTU269_Treponema acted as gatekeepers for both of the two clustered microbiotas. Nine OTUs assigned to seven taxa, i.e., Alloprevotella, Atopobium, Megasphaera, Oribacterium, Prevotella, Stomatobaculum, and Veillonella, were associated with both H7N9 patients with and without secondary bacterial lung infection in Cluster_1. In addition, two groups of healthy cohorts may have potential different susceptibilities to H7N9 infection. These findings suggest that two OP microbial colonization states of H7N9 patients were at different dysbiosis states, which may help determine the health status of H7N9 patients, as well as the susceptibility of healthy subjects to H7N9 infection.

Characteristics of three microbial colonization states in the duodenum of the cirrhotic patients.

Aim: Investigation of characteristics of different duodenal microbial colonization states in patients with liver cirrhosis (LC). Materials & methods: Deep-sequencing analyses of the 16S rRNA gene V1-V3 regions were performed. Results: Both bacterial compositions and richness were different between the three-clustered LC microbiotas, in other words, Cluster_1_LC, Cluster_2_LC and Cluster_3_LC. Cluster_1_LC were more likely at severe dysbiosis status due to its lowest modified cirrhosis dysbiosis ratio. OTU12_Prevotella and OTU10_Comamonas were most associated with Cluster_1_LC and Cluster_3_LC, respectively, while OTU38_Alloprevotella was vital in Cluster_2_LC. Pyruvate-ferredoxin/flavodoxin oxidoreductase, dihydroorotate dehydrogenase and branched-chain amino acid transport system substrate-binding protein were most associated with Cluster_1_LC, Cluster_2_LC and Cluster_3_LC, respectively. Conclusion: The three duodenal microbial colonization states had distinct representative characteristics, which might reflect the health status of cirrhotic patients.

Vital members in the gut microbiotas altered by two probiotic Bifidobacterium strains against liver damage in rats.

BACKGROUND: Probiotics are effective to rectify the imbalanced gut microbiota in the diseased cohorts. Two Bifidobacterium strains (LI09 and LI10) were found to alleviate D-galactosamine-induced liver damage (LD) in rats in our previous work. A series of bioinformatic and statistical analyses were performed to determine the vital bacteria in the gut microbiotas altered by the LI09 or LI10 in rats. RESULTS: Two groups of representative phylotypes could distinguish the gut microbiotas of LI09 or LI10 groups from the other groups. Among them, OTU170_Porphyromonadaceae acted as a gatekeeper in LI09 group, while OTU12_Bacteroides was determined with multiple correlations in the gut network of LI10 group. Multiple reduced OTUs associated with LC and increased OTUs associated with health were determined in LI09 or LI10 groups, among which, increased OTU51_Barnesiella and reduced OTU99_Barnesiella could be associated with the protective effects of both the two probiotics. The gut microbiotas in LI09, LI10 and positive control groups were clustered into three clusters, i.e., Cluster_1_Microbiota, Cluster_2_Microbiota and Cluster_3_Microbiota, by Partition Around Medoids clustering analysis. Cluster_2_Microbiota was determined at least dysbiotic status due to its greatest LD dysbiosis ratio, lowest levels of liver function variables and plasma cytokines compared with the two other clustered microbiotas, suggesting the treated rats in Cluster_2 were at better health status. CONCLUSION: Our findings suggest that OTU170_Porphyromonadaceae and OTU12_Bacteroides are vital in the gut microbiotas altered by LI09 and LI10. Characteristics of the LD cohorts treated by LI09 or LI10 at different gut microbial colonization states could help monitor the cohorts' health status.

Bacterial communities associated with tail fan necrosis in spiny lobster, Jasus edwardsii.

Spiny lobsters are among the most valuable seafood products, but their commercial value is greatly diminished by tail fan necrosis (TFN), an unsightly blackening and erosion of the posterior margins on the abdomen. The condition results from bacterial incursion following physical damage to the cuticle. In this current study, the bacterial communities on the cuticle of tail fans of wild spiny lobsters with and without TFN were examined using 16S rDNA Illumina sequencing to identify whether there is a group of bacteria associated with TFN. The bacterial communities in the affected cuticle had significantly less richness, diversity and evenness, but greater variability between samples than those in unaffected cuticle. There were 21 phylotypes closely associated with TFN, of which, those belonging to Aquimarina, Flavobacterium, Neptunomonas, Streptomyces, Flavobacteriaceae and Thiohalorhabdales were most important. The affected cuticle samples were clustered into two microbial colonization states, each characterized by distinct phylotypes that are closely associated with TFN, suggesting different phylotypes were associated with different microbial colonization states of TFN. These bacteria appear to develop their association through opportunistic pathways created by the provision of changes in the bacterial habitat associated with injury to the cuticle or compromised immunity subsequent to the injury.

Pathology of tail fan necrosis in the spiny lobster, Jasus edwardsii.

Tail fan necrosis (TFN) is the bacterial infection of the tail fan of spiny lobsters which leads to melanosis and erosion of the tail fan tissues. The condition is commonly found among spiny lobsters in aquaculture and commercial fisheries, and greatly reduces their commercial value. This study describes the pathology of TFN by examining the tail fans (telson, uropods) and internal organs (mid-gut, hepatopancreas, heart and gill) of 29 affected wild spiny lobsters (Jasus edwardsii) and 14 unaffected in New Zealand. Initial signs of TFN were observed around the margins of lacerations to the tail fan, with more extensive signs extending from these presumptive sites of initiation. The establishment of the condition at points of injury is consistent with the penetration of TFN through the cuticle and tissue layers of the affected tail fans, which is rarely seen in other forms of shell disease. Entry into these tissues was characterised initially by caseous necrosis and haemocyte accumulation, followed by the spread of these responses together with melanisation. Additional pathological changes to the tail fans included pseudomembrane formation, detachment of epidermis or cuticle, clotted haemolymph and fibrosis. Among internal organs, pathological changes were found in a total of two mid-gut, four heart and two gill samples from eight lobsters with TFN, while no suspected changes were found in the organs of lobsters without TFN. The causes of internal organ pathology associated with TFN in spiny lobsters warrants more detailed research.

Immune status of the spiny lobster Jasus edwardsii with tail fan necrosis.

Tail fan necrosis (TFN), a disorder commonly found in some populations of commercially fished and cultured lobsters, is thought to be initiated by injuries caused by handling and containment. The unsightly appearance of affected lobster tails significantly lowers their commercial value. Knowledge about TFN is limited. In this study we describe the morphological features of TFN and apply 6 common methods for evaluating the immune status of wild-caught Australasian red spiny lobsters Jasus edwardsii with and without TFN. The disease was more frequent in uropods than in telsons of the tail fan, and more extensive on the ventral versus the dorsal surfaces of the tail fan. Missing appendages (i.e. antenna, pereiopod or pleopod) were significantly more common and greater in number for individual lobsters affected with TFN versus those without, possibly as a result of handling in the fishery or as an indirect effect of the disease. Two immune parameters, total haemocyte count and phenoloxidase activity in the haemocyte lysate supernatant (HLS), were significantly compromised in lobsters with TFN. No differences were found in the other immune parameters, i.e. haemocyte viability, haemolymph bacterial count and the protein content of haemolymph plasma and HLS. The results are consistent with injury sustained during prior capture and handling that initiates TFN in these natural caught lobsters. These results raise some potential concerns about the fitness of lobsters in natural populations that are affected by TFN, and some potential solutions are proposed.