Mismatched human leukocyte antigen alleles protect against heterosexual HIV transmission

Genetic variation at the human leukocyte antigen (HLA) loci has been shown to be an important risk factor for progression to HIV disease, but its significance in infection is less well understood. We have investigated its role in HIV transmission in a cohort of individuals at risk for heterosexual infection. Analysis of over 80 individuals revealed that that the degree of concordance at HLA A, B, and DR loci differs significantly between transmitting and nontransmitting couples at risk for heterosexual HIV transmission (p <.02), suggesting that allogeneic immune responses may confer a degree of protection against HIV infection. Analysis of the frequencies of specific alleles at the A, B, and DR loci revealed a significantly higher frequency of HLA DR5 among exposed uninfected individuals, relative to population controls.

Analysis of the distribution of HLA-B alleles in populations from five continents

A two stage PCR-SSOP typing procedure, that permitted HLA-B allele assignment, was applied to DNA samples obtained from six diverse populations -Brazilian, Mexican (Series and Mestizos), Cuban (Caucasoid and Mulatto), South African Zulu, Omani, and Singapore Chinese. HLA-B allele frequencies and HLA-A/B two locus haplotype frequencies were compiled for each population.

The influence of transforming growth factor-beta1 gene polymorphisms on the severity of gingival overgrowth associated with concomitant use of cyclosporin A and a calcium channel blocker

BACKGROUND

The purpose of this study was to determine whether the prevalence and severity of gingival overgrowth in renal transplant recipients concomitantly treated with cyclosporin and a calcium channel blocker was associated with functional polymorphisms within the signal sequence of the transforming growth factor-(TGF)beta1 gene.

METHODS

The extent and severity of gingival overgrowth for 164 renal transplant recipients immunosuppressed with cyclosporin A and concomitantly taking a calcium channel blocker since transplant were entered into the study (86 in Manchester, 78 in Belfast). Two biallelic polymorphisms of the TGF-beta1 gene were studied at position +869, codon 10 (leucine to proline substitution), and position +915, codon 25 (arginine to proline substitution).

RESULTS

Subjects who were homozygous for proline at codon 10 had significantly higher overgrowth scores than those who were heterozygous (P= 0.03) or homozygous for leucine (P= 0.01). Subjects who were heterozygous (arginine/proline) at codon 25 had a significantly higher (P= 0.04) gingival overgrowth score than those who were homozygous for arginine. Logistic regression analysis indicated that for codon 25 independent predictors of severe gingival overgrowth were the heterozygous arginine/proline genotype (P= 0.009) and whether the individual was young (P= 0.05).

CONCLUSIONS

Polymorphisms in the TGF-beta1 gene influence the expression of gingival overgrowth in renal transplant recipients concomitantly treated with cyclosporin and a calcium channel blocker. The polymorphism in the TGF-beta1 gene at codon 25 represented an independent genetic determinant of severe gingival overgrowth in the susceptible subjects studied.

History of DNA typing for the human MHC

The last twenty years have seen an exponential growth in the application of DNA technology to the field of Histocompatibility and Immunogenetics (H&I). Initially, this was confined to a few research laboratories. However, the development and application of several different DNA methods by many laboratories has led to the situation whereby nearly every H&I laboratory performs some DNA typing for the detection of HLA alleles. It would not be unfair to say that H&I has shown diagnostic laboratories in other disciplines how useful the DNA techniques can be. This review attempts to summarise the history and application of DNA methods in the field of Histocompatibility (Table 1).

Comparison of serological and DNA HLA-DR typing results for transplantation in Western Europe, Eastern Europe, North America and South America

In a previous study, DNA typing revealed that 25% of serological HLA-DR typings of kidney transplants were incorrect. In the current study, we analyzed whether this error rate had improved in recent years, and whether there were differences according to geographical region. From 1988 to 1991 the error rate of serological typing improved slightly in Western Europe from 19% to 16%, and in North America, from 21% to 16%. In Eastern Europe, the error rate decreased from 49% to 33% in 1991, whereas the rate remained high in South America at 60% in 1988 and 72% in 1991. The high error rates in South America and Eastern Europe reflected a lack of good quality serological typing reagents. The 16% typing errors in Western Europe and North America demonstrated the current limit of serological techniques for cadaver donor typing and underlined the need for prospective DNA typing.

Comparative pathology of the diseases caused by Hendra and Nipah viruses

Information on the pathogenesis and transmissibility of Hendra and Nipah viruses was obtained by comparing their histopathology. Both viruses induced syncytial cells in vascular tissues and they were primarily vasotropic and/or neurotropic, generating interstitial pneumonia or encephalitis. Nipah virus in pigs was also epitheliotropic in respiratory epithelium and thus contagious.

Association between polymorphism in regulatory region of gene encoding tumour necrosis factor alpha and risk of Alzheimer's disease and vascular dementia: a case-control study

BACKGROUND

Deposition of beta-amyloid in the brains of patients with Alzheimer's disease is thought to precede a chain of events that leads to an inflammatory response by the brain. We postulated that genetic variation in the regulatory region of the gene for the proinflammatory cytokine tumour necrosis factor alpha (TNF-alpha) leads to increased risk of Alzheimer's disease and vascular dementia.

METHODS

A polymorphism in the regulatory region of the TNF-alpha gene was analysed in a case-control study. The polymorphism (C-850T) was typed in 242 patients with sporadic Alzheimer's disease, 81 patients with vascular dementia, 61 stroke patients without dementia, and 235 normal controls. These groups of individuals were also genotyped for the apolipoprotein E polymorphism, and the vascular dementia and stroke groups were typed at the HLA-DR locus.

FINDINGS

The distribution of TNF-alpha genotypes in the vascular dementia group differed significantly from that in the stroke and normal control groups, giving an odds ratio of 2.51 (95% CI 1.49-4.21) for the development of vascular dementia for individuals with a CT or TT genotype. Logistic regression analysis indicated that the possession of the T allele significantly increased the risk of Alzheimer's disease associated with carriage of the apolipoprotein E epsilon4 allele (odds ratio 2.73 [1.68-4.44] for those with apolipoprotein E epsilon4 but no TNF-alpha T, vs 4.62 [2.38-8.96] for those with apolipoprotein E epsilon4 and TNF-alpha T; p=0.03).

INTERPRETATION

Possession of the TNF-alpha T allele significantly increases the risk of vascular dementia, and increases the risk of Alzheimer's disease associated with apolipoprotein E. Although further research is needed, these findings suggest a potential role for anti-inflammatory therapy in vascular dementia and Alzheimer's disease, and perhaps especially in patients who have had a stroke.

Characterisation of a new HLA-B allele, HLA-B*0720, identified in the Cuban population

The HLA class I genes display significant levels of polymorphism, which is principally due to hypervariable regions located in the second and third exons. To date, 286 HLA-B alleles have been identified and characterised. We describe a new HLA-B*07 allele present in a Cuban Caucasoid individual, which has been officially named HLA-B*0720.

HLA class II typing of whole genome amplified mouth swab DNA

Postal collection of mouth swabs provides a cheap and convenient means of DNA sampling but hitherto has not provided sufficient genetic material for HLA typing by polymerase chain reaction using sequence-specific primers (PCR-SSP). This study examined the feasibility of collecting mouth swabs from a test population by post, amplifying the DNA by whole genome amplification and genotyping for selected HLA class II alleles. We optimised a strategy for whole genome amplification or primer extension preamplification using a random 15 base pair primer which resulted in a 1,000-fold increase in DNA template. The amplified DNA was of sufficient quality for analysis of selected HLA Class II alleles by PCR-SSP and PCR using sequence-specific oligonucleotide probes. To test the reliability of our data, blood DNA from 30 individuals in 10 families, previously tested for all DRB1 alleles in a routine diagnostic laboratory, was then tested in our laboratory for DRB1 *03 and *04 following whole genome amplification. Further whole genome amplified product from another 10 families was tested for DRB1 *03, *04 in our laboratory and then tested for all DRB1 alleles in a routine diagnostic laboratory. One repeat typing was required to achieve 100% concordance between laboratories. Amplification of whole genome amplified DNA by PCR-SSP was then extended successfully to low-resolution HLA DRB1, DQA1, DQB1 and DPB1 typing. Mouth swab collection by post, followed by whole genome amplification of DNA provides an effective strategy for genetic analysis of large cohorts. We have optimised conditions for HLA class II typing on whole genome amplified DNA collected by mouth swab, but this method could potentially be applied to low concentrations of DNA from other sources.

Frequency of HLA-B alleles in a Caucasoid population determined by a two-stage PCR-SSOP typing strategy

High resolution PCR-SSOP typing methods for HLA-B identification have been established and applied to a Northern Ireland population, using large enough numbers to give dependable allele frequencies. The six systems, which operate independently of each other, are intended for use as secondary typing systems following HLA-B identification with a medium resolution PCR-SSOP technique.

Analysis of the distribution of HLA-A alleles in populations from five continents

The variation and frequency of HLA-A genotypes were established by PCR-SSOP typing in diverse geographically distributed populations: Brazilian, Colombian Kogui, Cuban, Mexican, Omani, Singapore Chinese, and South African Zulu. HLA-A allelic families with only one allele were identified for HLA-A*01, -A*23, -A*25, -A*31, -A*32, -A*36, -A*43, -A*69, -A*80; and with two alleles for HLA-A*03, -A*11, -A*26, -A*29, -A*33, -A*34, and -A*66. Greater variation was detected for HLA-A*02, -A*24, and -A*68 allele families. Colombian Kogui and Mexican Seris showed the least diversity with respect to HLA-A alleles, albeit with small numbers tested, with only four and five HLA-A alleles identified, respectively. It would appear by their presence in all populations studied, either rural or indigenous, that certain alleles are very important in pathogen peptide presentation.

Characterization of HLA-B*3921 and confirmation of HLA-B*4415, two variant HLA-B alleles identified in the Omani population

We describe a variant HLA-B*39 allele present in two individuals from Oman, which has been officially named HLA-B*3921. In addition we confirm the existence of HLA-B*4415, an allele closely related to HLA-B*4501 differing only at the Bw4/Bw6 epitope.

Development of a PCR-SSOP approach capable of defining the natural killer cell inhibitory receptor (KIR) gene sequence repertoires

A molecular typing method based on polymerase chain reaction (PCR) amplification of three different target domains (immunoglobulin domains 1 and 3, and the transmembrane-cytoplasmic domain), followed by hybridisation with 26 digoxigenin-labelled sequence-specific oligonucleotide probes (SSOP) has been established for the polymorphic killer inhibitory receptor (KIR) genes. In addition to identifying the 12 KIR subfamilies, our PCR-SSOP typing approach could also distinguish the putative alleles, NKB1 and NKAT3, that comprise the KIR3DL1 subfamily. Ninety unrelated blood donors and 13 families (52 individuals), including both parents, were subjected to our KIR PCR-SSOP typing approach. All 12 KIR subfamilies, including a 2DS5 variant sequence, were present in the 90 individuals and displayed varied phenotype frequencies: 2DL1 (0.96), 2DL2 (0.31), 2DL3 (0.95), 2DS1 (0.56) 2DS2 (0.51), 2DS3 (0.27), 2DS4 (0.96), 2DS5v (0.35), 3DS1 (0.47), 3DL1 (0.96), 3DL2 (1.0) and 2DL4 (1.0). A total of 23 different KIR phenotypes were defined in this study, and 10 of these were only found on one occasion in one individual, indicating considerable diversity in the KIR phenotype profiles within the Irish population. Most individuals (93%) possessed the complement of inhibitory KIR specificities for the three well-defined HLA-B and -C ligands. An unusual probe pattern for 3DS1 was observed in 3 individuals indicating a variant 3DS1 gene sequence with changes at nucleotide positions 1185-1186, within the cytoplasmic domain. Sequencing analysis revealed a new single nucleotide polymorphism in exon 3 of 3DL1 NKB1(195, G-A) and a 22-bp deletion polymorphism in exon 5 of 2DS4 (nucleotides 777-798 deleted). A number of strong KIR associations were observed, namely 2DL1 with 2DL3, 2DS4 with 3DL1, 2DL2 with 2DS1/2DS2/2DS3, 2DS1 with 2DS3/2DS5v/3DS1, 2DS2 with 2DS3 and 2DS5v with 3DS1. Analysis of the KIR segregation observed in the 13 families confirmed these strong associations and permitted the definition of a number of partial KIR haplotypes, e.g. 2DL2-2DS1-2DS2-2DS3-3DL1. The segregation analysis concluded that at least 3 distinct gene loci encode 2DL1-4 and at least 4 gene loci encode the non-inhibitory KIR2DS1-2DS5. In the case of 3DL1-2 and 3DS1, our data suggests 3 gene loci, one for each subfamily.

Parvovirus B19 in kidney transplant patients

Renal transplant patients were screened for the presence of parvovirus B19, before transplantation and monthly for 4 months after transplantation, by means of a sensitive nested PCR assay. Upon screening plasma from 110 patients, we found that two asymptomatic patients were B19 DNA positive. One of these patients was PCR positive in the plasma sample taken 2 months after transplantation; the plasma contained anti-B19 IgG antibodies before transplant and throughout the follow-up period, with an increase in the IgG level in the second posttransplant sample coinciding with the detection of B19 DNA. IgM antibodies to B19 were not detected in this patient. Because, for this patient, the donor's spleen DNA was also B19 DNA positive, we suspect B19 transmission from the donor and limited B19 replication, inasmuch as this patient already had a primed immune response to B19. The other patient was PCR positive in the pretransplant and in the plasma sample taken 1 month after transplant and contained a strong anti-B19 IgG response in the pretransplant sample and throughout the follow-up period-and anti-B19 IgM antibodies were not detected before or after transplantation. By testing samples taken from this patient at 2 weeks, 2 months, and 3 months before transplantation, we were able to determine that the infection occurred shortly before transplantation. Unexpectedly, this graft failed and was removed 2 days after transplantation despite a negative cross-match. A pathological examination of the kidney indicated acute vascular rejection, suggesting a possible role for B19 in this complication.

Genetic polymorphism of IL-12 p40 gene in immune-mediated disease

Understanding of the genetic basis of autoimmune diseases is currently incomplete. Cytokine gene polymorphisms warrant consideration as factors explaining variation in the human immune and inflammatory responses and as candidate susceptibility genes for related pathological states. Interleukin 12 (IL-12) is a key regulator of the polarisation of immune responses to T helper 1 or 2 categories and plays a role in autoimmune and infectious diseases. Using a bioinformatic strategy, we aligned cDNA and expressed sequence tag sequences to identify putative polymorphic regions of the IL-12 p40 gene. Position 1188 in the 3' untranslated region (UTR) was polymorphic with the frequency of the common allele around 80% in healthy UK Caucasoids. PCR genotyping of multiple Caucasoid groups and an African group showed significant population variation. In a case-control design, the polymorphism was not associated with rheumatoid arthritis, Felty's syndrome or large granular lymphocyte syndrome with arthritis or multiple sclerosis. A nonsignificant increase in the B allele frequency was observed in the rare large granular lymphocyte syndrome without arthritis (odds ratio 2.02 95% CI 0.95-4.3). This new genetic marker could be useful in anthropological studies and should be investigated in other autoimmune, allergic, inflammatory and infectious diseases.

Effect of a dCTP:dTTP pool imbalance on DNA replication fidelity in Friend murine erythroleukemia cells

Nucleotide pool imbalances have been reported to affect the fidelity of DNA replication and repair in prokaryotic and eukaryotic cells. We have reported previously that the mutagen-hypersensitive thymidine kinase (TK)-deficient Friend erythroleukemia (FEL) cells (subclones 707BUF and 707BUE), have a more than sixfold increase in the dCTP:dTTP pool ratio when compared to that of wild-type, TK-positive (TK(+)) clone 707 cells. In this study we present the results of an investigation of the effect of the dCTP:dTTP pool imbalance on the accuracy of DNA replication within 707BUF cells. We examined the spontaneous mutation spectra occurring at the adenine phosphoribosyltransferase (aprt) locus within clone 707 (TK(+)) and 707BUF (TK(-)) FEL cells. Mutations recovered at the aprt locus in FEL cells comprised: base substitutions (43:73), frameshifts (14:13.5), and deletions (43:13.5) [clone 707 (TK(+)):707BUF (TK(-)), respectively, expressed as percentages]. A comparison of the mutation spectra obtained for the two cell lines did not reveal any significant increase in misincorporation of dCTP, the nucleotide in excess, in 707BUF (TK(-)) cells, during DNA replication synthesis. These data suggest that the dCTP:dTTP pool imbalance does not alter the fidelity of DNA replication synthesis in 707BUF (TK(-)) FEL cells. Rather, the predominance of GC --> AT transitions (53%) in the 707BUF (TK(-)) spectrum may reflect a reduced efficiency of repair by uracil DNA glycosylase of uracil residues within these cells.

Risk for Alzheimer's disease in older late-onset cases is associated with HLA-DRB1*03

The allele frequency of the HLA-DRB1 gene was compared between groups of 48 clinically diagnosed elderly Alzheimer's disease (AD) cases and 44 pathologically confirmed elderly control cases. Specific primers were used to PCR amplify the highly polymorphic second exon of HLA-DRB1 using DNA extracted from blood samples or frozen brain tissue. The allele type was identified using sequence specific oligonucleotide probes. The results showed an increased frequency of DRB1*03 (P < 0.006) and decreased frequency of DRB1*09 (P < 0.049) in the AD cases compared with the controls. The results suggest that DRB1*03 is associated with an increased risk and DRB1*09 a possible decreased risk for the development of late-onset AD with first detectable clinical symptoms occurring at age 75 years or greater.

Genetic, morphometric and immunohistochemical markers of latent coeliac disease

BACKGROUND

It is recognized that coeliac disease may exist in a latent form characterized by HLA-DR3 and increased counts of intra-epithelial lymphocytes (IELs) and gamma/delta T cells in jejunal biopsies. To determine whether subjects with persistent serological markers 4 and 13 years after a population screening survey have the HLA constitution of coeliac disease and/or minor morphometric abnormalities of the small intestine, including raised gamma/delta T-cell counts, as possible indicators of latent coeliac disease.

SUBJECTS

Participants with positive serology detected by the Belfast MONICA Project surveys (1983 and 1991) were subdivided into those with persistently positive serology (persistent serology), negative serology at follow-up (transient serology) and those with enteropathy (coeliac disease). Morphometric features were compared with MONICA controls who had negative serology and HLA antigen frequencies were compared with blood donor controls.

METHODS

Subjects were followed up in 1994-1996 and were re-tested for IgA antibodies to gliadin, endomysium and reticulin. HLA typing was carried out and IELs and gamma/delta T-cell counts were assessed in jejunal biopsies in subjects who gave consent.

RESULTS

Persistent serology mainly concerned antigliadin (AGA) and antireticulin (ARA) antibodies but one patient had positive antiendomysial antibody (EMA) and ARA in 1983, which became negative at follow-up, at which time they were positive for AGA. No significant differences were observed between IELs or gamma/delta T-cell counts when the persistent and transient groups were compared in turn with the MONICA controls. HLA-DR2 was expressed in 11 of 16 in the persistent group compared to 47 of 150 blood donor controls (P = 0.013). HLA-DR3 occurred in 15 of 17 coeliac patients compared to 37 of 150 blood donors (P = 0.00001).

CONCLUSIONS

Persistent serological markers following population screening do not appear to indicate latent coeliac disease.

Genetic association studies of tumour necrosis factor alpha and beta and tumour necrosis factor receptor 1 and 2 polymorphisms across the clinical spectrum of multiple sclerosis

Allelic association studies with microsatellite markers around the tumour-necrosis factor (TNF) genes have demonstrated significantly different allele distributions of TNF markers (a and b) between relapsing-remitting/secondary progressive multiple sclerosis (MS) (RR/SPMS) patients and normal controls. Considering the suspected genetic and immunological heterogeneity in MS, we tested this association in primary progressive MS (PPMS) patients. Elevated levels of serum soluble TNF receptors (sTNF-R) are reported in patients with gadolinium enhancing lesions, and animal models suggest a possible therapeutic role of sTNF-RI in MS. Thus we performed similar association studies using markers for the TNF-R genes. Gene association studies were carried out on 199-216 normal controls, 174 RR/SPMS patients and 102 PPMS patients using polymorphic dinucleotide repeat TNF markers (a, b and d), and separate markers for TNF-RI and TNF-RII. Forward primers were fluorescently labelled, polymerase chain reaction (PCR) products were analysed on a fluorescent fragment analyser, and Genescan 672 software was used for allele sizing. Samples were typed for HLA-DR antigens using PCR technology and sequence-specific oligonucleotide probes. TNFa marker allele distributions differed significantly between PPMS patients and controls (P = 0.028), largely attributable to an increase in the 118-bp TNFa allele in PPMS patients (P = 0.00024). Allele distributions were similar in PPMS and RR/SPMS patients (P = 0.91). Logistic regression analysis, however, indicated that these associations were not independent of that with HLA-DRB1*15. For the TNFb marker, the 127-bp allele showed association with both patient categories (PPMS vs. controls, P = 0.010; RR/SPMS vs. controls, P = 0.027), whilst the 128-bp allele occurred more frequently in controls (PPMS vs. controls, P = 0.036: RR/SPMS vs. controls, P = 0.0009). As with the TNFa 118 bp allele, the association with TNFb was not independent of the HLA association. No association occurred with the TNFd marker, and there were also no significant differences in allele frequencies between MS groups and controls regarding the marker for TNF-RI or TNF-RII. In Northern Irish patients the TNF contribution to MS genetic susceptibility is therefore similar across the clinical spectrum of the disease but is not independent of the association with HLA-DRB1*15.

Characterization of kinetoplast DNA minicircles of an Indian isolate of Leishmania donovani

Characterization of the kinetoplast DNA minicircles in a human pathogenic Indian isolate of Leishmania donovani has not been reported previously. Using inverse PCR, we constructed a library of PCR-amplified minicircle variable region from the kinetoplast DNA of this isolate. A combination of restriction enzyme digestion and nucleotide sequence analysis revealed five minicircle DNA sequence classes within the library, one of which was predominant, representing 75% of the kDNA network. Another distinct sequence class represented 15% of the minicircle network. Other minor sequence classes collectively constituted the remaining 10% of the network. Apart from generating basic information on the organisation and distribution of the different sequence classes within the minicircles, the DNA sequence analysis also revealed unique attributes to our minicircles. One was the surprising homology of our isolate (an Old World sp.) with distantly related New World Leishmania species. Secondly, open reading frames were also identified, indicating the possibility that these minicircles may have more than a structural role to play within the kinetoplast network.

Characterisation of a novel HLA-A pseudogene, HLA-BEL, with significant sequence identity with a gorilla MHC class I gene

During the development of an HLA-A polymerase chain reaction using sequence-specific oligonucleotide probes (PCR-SSOP) method for the identification of HLA-A*24 and -A*30 alleles, group amplification resulted in the formation of an unusual PCR product in certain individuals. This fragment was approximately 900 bp smaller than the expected product and was also detected in some non-HLA-A*24- and -A*30-positive individuals acting as negative controls for the group specific amplification. Nucleotide sequence analysis of this product identified it as a unique class I gene sequence displaying homology to both primate and human class I A-locus genes. The entire gene was amplified using PCR and the complete DNA sequence information from exon 1 to exon 8, including introns, was determined. A recombination event was identified which results in the fusion of intron 2 with intron 3, causing a deletion of the intervening exon 3 sequence. In addition, there are two cytosine insertions in the poly-cytosine stretch at the start of exon 4 which cause a frameshift and premature termination. The exon 1 and 2 sequences most closely align with the gorilla allele A*0501, displaying only five mismatches. PCR analysis has established that the gene is associated with the following HLA-A types: HLA-A*3001, -A*3301, -A*3303, -A*6802, -A*2901, -A*0203, -A*0205 and -A*31012. Reverse transcription (RT)-PCR analysis of individuals containing this gene failed to detect any mRNA transcription, suggesting that this is a previously undescribed non-expressed class I pseudogene which we have provisionally named HLA-BEL. Its unique gene structure gives a possible insight into the evolutionary pathway that created HLA class I genes.

Distribution of life cycle stages of Sarcoptes scabiei var wombati and effects of severe mange on common wombats in Victoria

Seven female and three male common wombats (Vombatus ursinus) collected from forested areas of Victoria (Australia) over a 10 mo period, 10 April 1997 to 22 February 1998 had at least 30% of their skin affected by severe hyperkeratotic sarcoptic mange. Mangy wombats were grazing during the day, could be readily approached, were in poor body condition, and lacked subcutaneous fat. The anterolateral surface of the body was most heavily parasitised with Sarcoptes scabiei var wombati followed by the posterolateral surface, the dorsal region between the ears, the ears, ventral abdomen, medial aspect of the legs, axillary and inguinal areas, and the dorsal midline. Larvae were the most prevalent life-cycle stage followed by eggs, nymphs, females, and males. Mite numbers and the severity of clinical signs, namely thickness of scale crust and the degree of alopecia, were correlated and were symmetrical on each side of the body. Fissuring of crust and skin only occurred when scale crust was present. Bacterial infections occurred in three of 10 wombats within lymph nodes or the pleural cavity. Lymphoid depletion did not occur in lymph nodes or spleens and prescapular lymph nodes contained a greater amount of nuclear debris in germinal centres than non-mangy wombats. Seven wombats had fatty change in their livers. Gonads of mature wombats were not active or had minimal activity. Significant histopathological changes were not seen in the gastrointestinal tract, kidney, brain, myocardium, spleen, thyroid, reproductive tract, and gonads. Hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, and concentrations of hemoglobin, lymphocytes, calcium, glucose, creatinine, total solids, total protein, albumin determined both colormetrically and electrophoretically, and globulins were significantly lower and concentrations of neutrophils, monocytes, phosphorus, urea, glutamate dehydrogenase, aspartate aminotransferase and creatine kinase were significantly higher in mangy versus captive wombats. Concentrations of erythrocytes, mean corpuscular hemoglobin, leucocytes, band neutrophils, eosinophils, nucleated erythrocytes, sodium, potassium, chloride, total bilirubin, alkaline phosphatase, and gamma glutamyltransferase for mangy wombats were not significantly different from that reported for captive wombats. Hematological and pathological changes in mangy wombats were consistent with anemia, inflammation, and changes seen with starvation.