Thesis (PhD (Pathology. Anatgomical Pathology))--University of Stellenbosch, 2005. / The formation of granulomas at the site of antigen presentation in both tuberculosis and sarcoidosis is an essential component of host immunity for controlling inflammation. Granuloma formation is a complex process that also requires recruitment and activation of lymphocytes and macrophages to the site of infection and arrangement into a granuloma. It is dependant on the activation of especially IFNγ secreting CD4+ T cells, resulting in a Th1 profile. However, it is suggested that a persistently high IFNγ is responsible for the damage caused by granulomatous disease and that moderating cytokines, resulting in a Th0 profile, are necessary to down-regulate the IFNγ response to more appropriate levels later in the disease process, after the antigen has been effectively contained. I propose that: “Cytokine profiles determine clinical and histopathological phenotypes of disease. This thesis tests the hypothesis that it will be reflected by cytokine expression profiles in granulomas in different forms of tuberculosis and in sarcoidosis.” To examine this, biopsy tissue was obtained from patients with pulmonary cavitary tuberculosis, pleural tuberculosis in HIV sero-negative and sero-positive patients, and sarcoidosis. The diagnosis of tuberculosis or sarcoidosis was confirmed, granulomas were characterised as necrotic or non-necrotic, sarcoidosis cases were graded histologically and in situ hybridisation was performed for IL-12-, IFNγ-, TNFα- and IL-4-mRNA. In all patients with pleural tuberculosis, a Th0 profile was noted, while necrotic granulomas were more evident in HIV positive than HIV negative patients. There was a clear association between TNFα and necrosis in tuberculous granulomas that may be ascribed to the increased apoptotic activity of TNFα. An increase in IFNγ correlated with an increase in necrosis, supporting the theory that high IFNγ levels later in disease is detrimental. This effect may be enhanced by a strong presence of TNFα positive cells. An increase in both Th1 and Th2 cytokine mRNA in HIV positive patients supports the theory that an overproduction of cytokines may be a mechanism to compensate for the failure of another immune effector mechanism. Findings in pulmonary tuberculosis were similar to those in pleural tuberculosis. In all sarcoidosis cases the presence of a very strong Th1 and TNFα, but no Th0 response was confirmed. None of the differences in either the histological grading, or the clinical outcome of patients were reflected in the cytokine profile. It is possible that this profile does not reflect the histological grade of disease or that it may reflect various stages of disease. These findings support the theory that a strong Th1 presence later in disease, in conjunction with TNFα may induce fibrosis, as most of these cases showed signs of at least focal fibrosis. Numerous aspects, including a T helper response are involved in granulomatous inflammation. The earlier dogma of good, beneficial (Th1) versus evil, detrimental (Th2), is an oversimplification of a very complex process. It is clear that the effect of a cytokine depends at least partially on the stage of disease. The balance between the various cytokines, and the levels of these cytokines contribute to their role in resolution or disease progression. An early, pure Th1 response may be beneficial if effectively clearing the granuloma-inducing antigen. At this stage, a Th2 presence will be harmful as clearing of the antigen will not be as effective. In chronic disease where failure to remove the antigen results in progression of granulomas with subsequent necrosis and/or fibrosis, a proinflammatory Th1 response may be detrimental and minimising of this effect is needed. An overly strong presence of the various cytokines may also be detrimental, while lower levels will be beneficial.

Thesis (MSc)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Pre-eclampsia is a condition unique to pregnancy and primarily affects the maternal and placental vascular endothelium. It has significant morbidity and mortality consequences for both mother and infant. Despite global research into the aetiology of the condition, the cause for this condition remains unknown. Several factors, including a strong family history of hypertension in pregnancy point to a familial or genetic component in the pathophysiology of this complication. The purpose of this research project was to investigate candidate genes implicated in endothelial damage. Common methylene-tetra-hydrofolate reductase (MTHFR) gene mutations C677T and A1298C, factor V Leiden mutation R506Q and prothrombin mutation A20210G were investigated in 50 patients with an uncomplicated pregnancy outcome (controls) and 350 patients with various clinical manifestations of preeclampsia, including severe, early onset forms and abruptio placentae. Fasting homocystein levels were determined biochemically on all participants. In addition, 126 consecutive pregnant patients were recruited at booking, fasting lipograms were performed on them as well as mutation screening of 7 common mutations in the low-density lipoprotein receptor gene. This was correlated with eventual pregnancy outcome, and those with an uncomplicated outcome were selected as an additional control group. A significant association between hyperhomocysteinaemia and early onset severe pre-eclampsia could be demonstrated. Mutant allele T of the C677T mutation could be associated with hyperhomocysteinaemia but not with pre-eclampsia whilst mutant allele C of mutation A1298C demonstrated a significant correlation with diastolic blood pressure. In addition, combined heterozygosity for these mutations may serve as a marker for abruptio placentae. / ENGLISH ABSTRACT: Pre-eklampsie is 'n hipertensiewe toestand uniek aan menslike swangerskap en dit affekteer hoofsaaklik die vaskulêre endoteel. Die toestand hou ernstige morbiditeit en mortaliteit vir beide ma en baba in en na jare se navorsing is die oorsaak van hierdie toestand steeds onbekend. Epidemiologiese studies toon 'n duidelike familiële verband aan wat die vermoede laat ontstaan dat daar 'n onderliggende genetiese aspek tot die ontwikkeling van die siektetoestand is. Die doel van hierdie navorsingsprojek was om gene te ondersoek wat geïmpliseer word in endoteel skade. Twee algemene mutasies, C677T en A1298C in die MTHFR geen asook faktor V Leiden R506Q en protrombien A20210G mutasies is ontleed in 50 pasiënte met 'n ongekompliseerde swangerskapsverloop en in 350 pasiënte met 'n swangerskap gekompliseer deur verskillende kliniese manifestasies van die siekteproses, insluitende vroeë aankoms erge pre-eklampsie en abruptio placentae. Op alle pasiënte is ook 'n vastende homosistiën vlak biochemies bepaal. 'n Verdere 126 opeenvolgende pasiënte is gewerf tydens hulle eerste besoek aan die voorgeboortekliniek en vastende lipogramme is op almal uitgevoer. Mutasie sifting vir 7 algemene mutasies in die lae-digtheids lipoproteïen reseptor geen is op hierdie groep gedoen en die resultaat is met die uiteindelike swangerskapsuitkoms gekorreleer. Pasiënte met 'n uitkoms ongekompliseer deur hipertensie is gekies om deel te wees van 'n verdere kontrolegroep. Daar was 'n betekenisvolle verband tussen hiperhomositiënemie en erge, vroeë aankoms pre-eklampsie. Die T alleel van die C677T mutasie is geassosieer met hiperhomosistiënemie maar nie met pre-eklampsie nie. Die C alleel van die A 1298C mutasie toon 'n betekenisvolle verband met diastoliese bloeddruk. Gekombineerde heterosigositeit vir beide MTHFR mutasies kan 'n moontlike merker vir abruptio placentae wees.

Thesis (PhD (Med))--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Background and Objective: The most common cause of severe proteinuria/nephrotic syndrome (NS) in children worldwide is minimal change disease (MCD). This is also the pattern observed in white and Indian children in South Africa (SA). By contrast, black and mixed race/coloured children of Southern Africa in the 1960s to 1990s were shown to have a different pattern of NS. One of the main differences was the frequency of hepatitis B virus (HBV) associated glomerulonephritis, usually membranous glomerulonephritis (MGN). The objective of this project was a clinicopathological study of this subgroup of nephrotic children to document the disease further and in particular to seek correlations between pathological and clinical features including prognosis. A central focus was to document the detailed ultrastructural examination of the renal biopsies of these children and to correlate the spectrum of pathological features with demographic, clinical, laboratory and prognostic features. The hypothesis was that the clinicopathological features of HBV MGN in children differed substantially from idiopathic MGN in general (children and adults) and also from HBV MGN in adults and that HBV MGN in children should be viewed as a distinct disease. Patients and methods: The childhood (12 years and younger) patient cohort was 309 children with severe proteinuria/nephrotic syndrome who presented at Tygerberg Hospital (TBH) over a 21 year period from 1974-1995, including 67 children from Namibia. The study group was 71 children with HBV MGN who were followed up to 2005. The comparative adult group was 45 adults with MGN of whom 12 had HBV MGN and 33 idiopathic MGN. (A comparison could not be made with idiopathic MGN in childhood as this centre only had 2 such patients during the study period.) Demographic, clinical, laboratory and renal pathology data were collected, compared and correlated. Results: HBV associated MGN was the most frequent cause of NS in the Namibian subgroup, 25/67 (37%) and the third most frequent, 71/309 (23%) in the childhood cohort as a whole. The MGN group was 86% (71/83) of the total HBV childhood nephrotic cohort, by far the dominant subgroup. The average age of the 71 children with HBV MGN was 6.0 years (range 2-12 years) at presentation and boys comprised 80% of the group. Hepatitis B envelope antigen (HBeAg) was identified in the serum of 87% of children tested. Laboratory features different from idiopathic MGN included more prominent haematuria, mildly raised serum transaminases and more frequently lowered serum C3 and C4 levels. Light microscopic examination of renal biopsies showed mesangial proliferation in all patients but with minimal glomerular sclerosis and interstitial disease. On ultrastructural examination mesangial and subendothelial deposits were common and prominent as was mesangial interposition. The MGN of HBV in children therefore frequently showed mesangiocapillary glomerulonephritis (MCGN) features in addition to the subepithelial deposits of MGN. The subgroup of 23 whose renal biopsies displayed severe mesangial interposition in addition to the subepithelial deposits of MGN were termed the mixed HBV MGN-mesangiocapillary GN group. Virus like bodies and tubuloreticular inclusion bodies were both found in more than 80% of biopsies of childhood HBV MGN. HBeAg was identified in the subepithelial deposits in the glomeruli. This was the first time this feature was demonstrated in Africa. The 46 South African children with HBV MGN showed a cumulative remission rate of 25% at 2 years and 52% at 4 years. Seven of the children (10%) of the total cohort developed chronic renal failure (CRF). Age of 6 years and above at presentation and severe mesangial deposits on biopsy correlated with fewer remissions and poorer outcome. In 3 patients the interval between the diagnosis of HBV MGN and the onset of CRF was more than 19 years with the longest being 23 years. The 358 cases of childhood HBV MGN from Southern Africa constitute 37% of the reported childhood patients. Comparative data A comparison was made between the 71 children with HBV MGN, 12 adults with HBV MGN and 33 adults with idiopathic MGN. The main differences were that both HBV MGN groups included only coloured and black patients and were more predominantly male while the idiopathic MGN group included all races. In the HBV patients, haematuria was more frequent and severe, liver enzymes were frequently raised and C3 more frequently reduced than in the idiopathic cohort. Both groups of adult MGN patients had normal C4 levels while the childhood HBV MGN group had reduced C4 levels. The immune complex pattern in both of the HBV MGN adult and childhood groups on biopsy was similar with more mesangial and subendothelial deposits as well as mesangial interposition than the idiopathic group. Despite this similarity between the two HBV groups, both adult groups showed more glomerular sclerosis and interstitial disease than the childhood group. The clinical outcome of the children’s cohort was better than the other 2 groups with remission (52%) more frequent at 4 years (p< 0.01) and better renal and patient survival. Including the 83 cases from this series, at least 1243 renal biopsy proven cases of HBV MGN have been reported in the English literature; children (80%) and adults (20%). The male gender predominance in both age groups for HBV MGN is similar (children 79%; adults 84%) and significantly greater than for idiopathic MGN. Conclusions: The findings confirm that HBV MGN in children is a distinct form of GN which broadens the classical morphologic description of MGN by often including a number of mesangiocapillary GN features. The subgroup of renal biopsies with the most severe mesangiocapillary GN features was classified as the mixed HBV MGNmesangiocapillary GN group. The MGN spectrum as a whole comprised 86% of the HBV positive childhood group. HBV MGN was the most frequent association with NS/severe proteinuria in the Namibian subgroup (37%) and the third largest group (19%) in the SA children. It showed a relatively high spontaneous remission rate but at least 10% of the children developed renal failure. Age of 6 years and above at presentation and severe mesangial deposits on biopsy correlated with fewer remissions and poorer outcome. Extended follow up (more than 15 years) was required to demonstrate renal failure in some patients in the poor outcome group. Urbanisation, associated with lower HBV carrier rates, and HBV vaccination (initiated routinely in 1995 in SA), have already lead to a sharply decreasing incidence of this disease in SA. HBV MGN has been a valuable and possibly unique model of human GN and MGN in particular in that the HBeAg has been identified in both the serum and glomeruli enabling confirmation of the aetiological role of HBeAg. / AFRIKAANSE OPSOMMING: Agtergrond en Doelwit: Die algemeenste oorsaak van erge proteïenurie/nefrotiese sindroom (NS) in kinders wêreldwyd is minimale veranderingsiekte. Hierdie patroon kom ook voor in blanke- en Indiër kinders in Suid-Afrika. In teenstelling hiermee is aangetoon dat swart en kleurling/gemengde ras kinders in Suider Afrika tussen die jare 1960s tot 1990s ’n ander patroon van nefrotiese sindroom gehad het. Een van die hoof verskille was die algemene voorkoms van hepatitis B virus (HBV) geassosieerde glomerulonefritis, gewoonlik membraneuse glomerulonefritis (MGN). Die doelwit van hierdie projek was ’n klinies-patologiese studie van hierdie subgroep van nefrotiese kinders ten einde die siekte verder te beskryf en veral om korrelasies te tref tussen patologiese en kliniese kenmerke insluitende prognose. Die gedetaileerde ultrastrukturele ondersoek van die kinders se nierbiopsies en die korrelasie van die spektrum patologiese kenmerke met demografiese, kliniese, laboratorium en prognostiese kenmerke was ‘n sentrale fokusarea. Die hipotese was dat die klinies-patologiese kenmerke van HBV MGN in kinders wesenlik van idiopatiese MGN in die algemeen verskil (in kinders en volwassenes) en ook van HBV MGN in volwassenes, en dat die beeld in kinders as ’n afsonderlike siekte beskou behoort te word. Pasiënte en metodes: Die kinder kohort (12 jaar en jonger) was 309 kinders met erge proteïenurie/nefrotiese sindroom wie in Tygerberg Hospitaal (TBH) behandel was oor ‘n 21 jarige periode vanaf 1974 tot 1995, insluitende 67 kinders van Namibië. Die studiegroep was 71 kinders met HBV MGN wie waar moontlik tot 2005 opgevolg was. Die vergelykende volwasse groep was 45 volwassenes met MGN van wie 12 HBV MGN gehad het en 33 idiopatiese MGN. (’n Vergelyking met idiopatiese MGN in kinders kon nie gedoen word nie omdat hierdie sentrum net twee sulke pasiënte tydens die studietyd behandel het.) Demografiese, kliniese, laboratorium en nierpatologie inligting is versamel, vergelyk en gekorreleer. Resultate: HBV geassosieerde MGN was die algemeenste oorsaak van NS in die Namibiese subgroep, 25/67 (37%) en die derde mees algemeen, 71/309 (23%) in die kinder kohort as geheel. Die MGN groep was 86% (71/83) van die totale HBV kinder nefrotiese kohort en verreweg die oorheersende subgroep. Die gemiddelde ouderdom van die 71 kinders met HBV MGN by presentering was 6.0 jaar (reikwydte 2-12 jaar) en seuns het 80% van die groep behels. Hepatitis B omhullingsantigeen (envelope antigen- HBeAg) is aangetoon in die serum van 87% van die kinders wie daarvoor getoets is. Laboratoriumkenmerke wat van idiopatiese MGN verskil het, het ingesluit meer prominente hematurie, gering verhoogde serum transaminases en meer dikwels verlaagde serum C3 en C4 vlakke. Ligmikroskopiese ondersoek van die nierbiopsies het mesangiale proliferasie in elke pasiënt getoon, maar met minimale glomerulêre sklerose en interstisiële siekte. Met ultrastrukturele ondersoek was mesangiale en subendoteliële neerslae asook mesangiale interposisie algemeen. Die MGN van HBV in kinders het dus dikwels kenmerke van mesangiokapillêre glomerulonefritis getoon bo en behalwe die subepiteliële neerslae van MGN. Die ondergroep van 23 van wie die nierbiopsies erge mesangiale interposisie aangetoon het asook die subepiteliale neerslae van MGN is die gemengde HBV MGN-mesangiokapillêre GN groep genoem. Virustipe liggaampies en tubuloretikulêre insluitingsliggaampies is in meer as 80% van die biopsies bevestig. HBeAg was in die subepiteliële neerslae identifiseer. Dit was die eerste keer dat hierdie kenmerk in Afrika identifiseer is. Die 46 Suid-Afrikaanse kinders het ’n kumulatiewe remissie koers van 25% teen 2 jaar en van 52% teen 4 jaar getoon. Sewe van die kinders (10%) van die hele kohort het kroniese nierversaking (KNV) ontwikkel. Ouderdom van 6 jaar en meer by presentasie en erge mesangiale neerslae in ‘n biopsie het met minder remissies en ’n swakker uitkoms gekorreleer. Drie pasiënte het meer as 19 jaar na aanvanklike voordoening ooglopende KNV ontwikkel, waarvan 23 jaar die langste interval was. Die 358 gevalle van kinderjare HBV MGN van Suidelike-Afrika maak 37% uit van die gerapporteerde kinder pasiënte. Vergelykende data ’n Vergelyking is getref tussen die 71 kinders met HBV MGN, 12 volwassenes met HBV MGN en 33 volwassenes met idiopatiese MGN. Die hoof verskille was dat beide HBV groepe net kleurling en swart pasiënte ingesluit het en meer oorwegend manlik was, terwyl die idiopatiese groep alle rasse ingesluit het. In die HBV pasiënte was hematurie meer algemeen en erg, lewer ensieme meer dikwels verhoog en C3 meer dikwels verlaag as in die idiopatiese kohort. Beide groepe van volwasse MGN pasiënte het normale C4 vlakke getoon terwyl die kindergroep met HBV MGN verlaagde C4 vlakke bewys het. Die immuunkompleks patroon in biopsies van die HBV MGN volwasse en kindergroepe was soortgelyk met meer mesangiale en subendoteliële neerslae asook meer mesangiale interposisie as in die idiopatiese groep. Ten spyte van hierdie ooreenkoms tussen die twee HBV groepe, het die twee volwasse groepe meer glomerulêre sklerose en interstisiële siekte as die kindergroep vertoon. Die kliniese uitkoms van die kinderkohort was beter as die ander twee groepe met remissie (52%) wat meer algemeen was teen 4 jaar (p< 0.01) en met beter nier- en pasïent oorlewing. Ingeslote die 83 gevalle van hierdie reeks, is ten minste 1243 nierbiopsie bewysde gevalle van HBV MGN in kinders (80%) en volwassenes (20%) in die Engelse literatuur gerapporteer. Die manlike oorheersing in beide ouderdomsgroepe van HBV MGN is soortgelyk (kinders 79%; volwassenes 84%) en betekenisvol meer as vir idiopatiese MGN. Gevolgtrekkings: Die bevindinge bevestig dat HBV MGN in kinders ’n afsonderlike vorm van GN is wat die klassieke beskrywing van MGN verbreed deur die algemene insluiting van ’n aantal mesangiokapillêre GN kenmerke. Die ondergroep van nier biopsies met erge mesangiokapillêre GN kenmerke is as die gemengde HBV MGNmesangiokapillêre GN groep geklassifiseer. Die MGN spektrum in geheel het 86% van die HBV positiewe kindergroep behels. HBV MGN was die mees algemene assosiasie met NS/erge proteïenurie in die Namibiese subgroep (37%) en die derde grootse groep (19%) onder die SA kinders. Die siekte het ’n relatiewe hoë spontane remissiekoers getoon, maar ten minste 10% van die kinders het nierversaking ontwikkel. Ouderdom van 6 jaar en meer by presentasie en erge mesangiale neerslae in ‘n nierbiopsie het met minder remissies en ’n slegter uitkoms gekorreleer. Uitgebreide opvolg (meer as 15 jaar) was nodig om nierversaking in sommige van die swak uitkomsgroep aan te toon. Verstedeliking is geassosieerd met laer HBV draersyfers en hierdie faktor saam met algemene HBV inenting in die kinderjare (wat in 1995 in SA begin was), het ’n skerp daling in die voorkoms van hierdie siekte in SA teweeg gebring. HBV MGN is ’n waardevolle en moontlik unieke model van menslike GN en MGN, veral omdat die HBeAg in beide die serum en glomeruli identifiseer kon word om die etiologiese rol van HBeAg te bevestig.

Thesis (PhD (Pathology. Anatomical Pathology))--University of Stellenbosch, 2006. / Patients with chronic gastro-oesophageal reflux disease are predisposed to Barrett’s metaplasia and oesophageal adenocarcinoma. The availability of molecular markers that can objectively identify patients with Barrett’s oesophagus at increased risk of carcinoma is highly desirable. A literature search was conducted to identify potentially useful biomarkers for genotype-phenotype correlation studies in South African patients with Barrett’s oesophagus. The COX-2, c-myb and c-myc genes selected for mRNA expression analysis were analysed in 26 patients with Barrett’s metaplasia (BM) without dysplasia; 14 with Barrett’s oesophagus and dysplasia (BD); 2 patients with Barrett’s adenocarcinoma (BAC); 19 with erosive oesophagitis (ERD); 25 with non-erosive oesophagitis (NERD) and 19 control individuals with a normal gastroscopy and no gastro-oesophageal reflux disease (GORD) symptoms. In the BD/BAC group, 69% (11/16) showed increased c-myb mRNA expression compared with 35% (9/26) in the BM group (p = 0.03). A statistically significant difference (p = 0.002) in c-myb expression was also observed between Barrett’s patients (20/42, 48%) and the control groups (9/63, 14%). In the BD patients, 21% (3/14) had increased c-myc mRNA expression compared with none in those with BM (p < 0.05) and BAC. No significant differences in mRNA expression levels were observed between ethnic groups for the genes analysed. In an attempt to determine whether the low expression level of c-myc in the study cohort may be related to possible gene-gene interaction, DNA samples of 199 individuals were subjected to genotyping of the functional GT-repeat polymorphism in the promoter region of the NRAMP1/SLC11A1 gene. Both these genes are involved in iron metabolism and c-myc is known to repress NRAMP1/SLC11A1. Genotype and allele frequencies were similar in all the groups studied with the 3/3 genotype being the most common. However, none of the three above-mentioned BD patients with increased c-myc mRNA expression had the 3/3 genotype. Therefore, although small in number, c-myc-NRAMP1/SLC11A1 interaction may be of adverse significance in patients with allele 2. TP53 mutation analysis was performed on 68 Barrett’s patients, and TP53 immuno-staining on oesophageal biopsy specimens of 55 subjects. Sporadic TP53 mutations were not identified in any of the patients with BM or dysplasia without BAC. Immuno-histochemistry staining of 2+ and 3+ intensity was similar in patients with metaplasia and dysplasia (58%). The low mutation frequency and relative non-specificity of TP53 immunostaining observed in Barrett’s patients seem to preclude its widespread use as a screening tool. TP53 mutation detection may however be useful for risk stratification once dysplasia has been diagnosed, as mutations G245R and D281Y were identified in two patients with BAC. Of the genes studied in the South African population, c-myb represents the most useful marker for early detection of an increased cancer risk in Barrett’s patients. In future, patients with Barrett’s oesophagus may benefit from genetic assessment to complement existing cancer surveillance and treatment strategies.

Thesis (MMedSc )--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The present study investigated in particularly the specific nature of the supporting stromal layer located between the implanted human cyst and host murine tissue, which has yet to be reported. During an initial phase of this study, the particular light microscopic properties of the existing hematoxylin and eosin (H&E) stained experimental cyst was investigated, with regards to the presence or absence of specific morphological features, namely spongiosis, exocytosis, epithelial keratinization, epithelial thickness and hyperplasia, and the vascularity and fibrosis present in the stroma of these experimental sections. Subsequent analysis reported significant spongiosis, in addition to increased exocytosis of immune cells and epithelial keratinization in a number of cysts. Additionally, increased epithelial thickness and hyperplasia was reported in only 2 / 10 experimental tissues, whereas increased vascularity was observed in the stroma following analysis of H&E and Special staining, such as Verhoeff-von Gieson and Masson trichrome results. During the second phase of the study, immunohistochemical analysis with a particularly wide array of antibodies raised against specific human and mouse antigens had been applied. This involved automated immunohistochemical staining with mouse anti-human primary antibodies, in addition to manual staining with rabbit anti-mouse primary antibodies. Subsequent visualization was achieved by means of linking to biotinylated secondary antibodies, and Streptavidin-HRP incubation for standard visualization, followed by counterstaining with Hematoxylin. Maintained positive expression of cytokeratins 5, 13, and 14 was demonstrated in both control human vaginal mucosa and experimental cysts, whereas similar findings were not reported for cytokeratin 1, given the vast keratinization which was observed. Human collagen type IV and laminin of the basement membrane reported positive expression in 9 / 10 and 6 / 10 control human vaginal mucosa tissues respectively. In comparison, negative mouse collagen type IV and laminin was reported in most experimental cysts compared to positive staining in positive control mouse tissues. Immunohistochemical staining for human elastin, fibronectin, von Willebrand factor, and fibroblasts revealed maintained positive staining in all control human vaginal mucosa and experimental cysts. However, maintained expression of CD34 (endothelial marker), CD1a (langerhans cells), and human VEGFR-3 in experimental cysts was not demonstrated, compared to positive expression in control human vaginal mucosa. Subsequent analysis of murine antigens illustrated uniformly negative staining for mouse fibronectin, langerhans cells (CD207), and fibroblasts, in addition to negative staining in positive control mouse tissue sections. Furthermore, negative staining for mouse VEGFR-2 was reported in all experimental cysts; however strong positive staining of this marker in mouse kidney tissue had been reported. The findings of this study suggested that the exact nature of the stromal layer is of both human and murine origin. Furthermore, the tissue region located beneath the human vaginal epithelium is suggested to be of human nature, whereas the second distinct region located at the periphery of experimental cyst tissues, is suggested to be murine origin; however the findings of immunohistochemical analysis could not illustrate definitively the exact nature of the intermediate stromal layer, but could in fact demonstrate a mixture of human and murine tissue. / AFRIKAANSE OPSOMMING: Die huidige studie het die spesifieke molekulêre en histologiese eienskappe van die stromale laag geleë tussen menslike sist- en muis velweefsel bestudeer, wat tans nog nie bekend is nie. Gedurende die eerste fase van hierdie studie is die besondere lig-mikroskopiese eienskappe van die bestaande hematoksilien en eosien (H&E) eksperimentele siste bestudeer, met betrekking tot die aan- of afwesigheid van spesifieke morfologiese eienskappe, naamlik spongiose, eksositose van immuunselle, epiteel keratinisasie, epiteel dikte en hiperplasie, en laastens die stromale vaskulariteit en fibrose. Gevolglike analise het daarop gedui dat beduidende spongiose, eksositose en epiteel keratinisasie gevind word in die eksperimentele siste in vergelyking met kontrole vaginal weefsel. Hierteenoor is die verdikking van die epiteel en hiperplasie in slegs 2 / 10 eksperimentele siste gevind, terwyl vermeerderde vaskulariteit aangedui is na gevolglike H&E en spesiale (soos byvoorbeeld Verhoeff-von Gieson en Masson trichrome) kleuringsresultate. Die tweede fase van die studie het die immunokleuring met verskeie mens- en muis spesifieke antiliggame behels, waarby die uitdrukking van verskeie mens antigene vergelyk is met dié van muis. As sulks is ge-automatiseerde immunohistochemie toegepas met muis primêre antiliggame, tesame met fisiese kleuring met konyn primêre antiliggame toegepas. Gevolglike visualisasie is aangedui deur middel van binding met sekondêre antiliggaam en Streptavidin- HRP, gevolg deur teenkleuring met Hematoksilien. Algehele behoud van positiewe uitdrukking van sitokeratien 5, 13, en 14 is bevind, terwyl sitokeratien 1 uitdrukking nie daarwerklik vergelykbaar is met dié van kontrole mens vaginale weefsel nie. Die uitdrukking van mens kollageen IV en laminien van die basaal membraan is verder bestudeer, en het egter positiewe kleuring in 9 / 10 en 6 / 10 van kontrole mens vaginale mukosa aangedui. In vergelykking hiermee kon die huidige bevindings egter net positiewe kleuring in 4 / 10 en 3 / 10 eksperimentele siste vir kollageen IV en laminien onderskeidelik, illustreer. Immunohistochemiese analise van menslike elastien, fibronektien, von Willebrand (vW) faktor en fibroblaste het op deurgaans positiewe uitdrukking van hierdie merkers aangedui in beide eksperimentele en kontrole menslike weefsel. In teenstelling hiermee is volgehoue uitdrukking van CD34 (endoteel merker), CD1a (Langerhans sel merker) en mens VEGFR-3 in ekperimentele siste egter nie illustreerbaar nie, in vergelykking met deurgaans positiewe uitdrukking van hierdie antigene in kontrole mens vaginale mukosa. In opvolging is deurgaans negatiewe uitdrukking van muis fibronektien, langerhans sel (CD207) en fibroblaste bevestig, terwyl negatiewe kleuring ook deurgaans in positiwe kontrole muis weefsel, bekom deur die disseksie van ‘n naakte muis, gevind is. Verder is ook negatiewe kleuring vir VEGFR-2 in alle eksperimentele siste gevind, terwyl egter sterk positiewe kleuring in muis nierweefsel as positiewe weefsel gevind is. Die resultate van die huidige studie het daarop gedui dat die stromale laag onderliggend tot mens vaginale epiteel van menslike oorsprong is, terwyl die periferale stroma onderliggend tot muis velweefsel, ongetwyfeld van muis oorsprong is. Laastens kon die spesifieke oorsprong van die tussenliggende stroma nie aangedui word nie, maar dat dit moontlik uit beide menslike- en muisweefsel bestaan.